B.Pharmacy 5th Semester Pharmacognosy and Phytochemistry II Important Question Answer 

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Pharmacognosy and Phytochemistry II Very Short Question Answer {2 Marks}  

 

1. Define glycosides. 
Glycosides are organic compounds where a sugar moiety is bound to a non-sugar part (aglycone) via a glycosidic bond. Example: Digoxin. 

2. Define pharmacognosy and phytochemistry. 
Pharmacognosy is the study of drugs obtained from natural sources. Phytochemistry deals with the chemistry of plant constituents. 

3. What is the chemical test used for identification of volatile oils? 
Sudan III staining test and turbidity with alcoholic solution are used. Volatile oils show red coloration with Sudan III. 

4. What is the importance of secondary metabolites? 
They possess therapeutic properties like antimicrobial, anticancer, and antioxidant effects and are important in drug development. 

5. Write the biological source and medicinal uses of Vinca drug. 
Source: Catharanthus roseus (Apocynaceae). Uses: Anticancer (vincristine and vinblastine used in leukemia and lymphoma). 

 

6. Write the chemical test used for identification of alkaloids. 
Mayer’s test: Cream-colored precipitate; Dragendorff’s test: Orange-red precipitate indicates presence of alkaloids. 

7. Write the biological source and active constituents of drug used as antihypertensive. 
Source: Rauwolfia serpentina. Active constituent: Reserpine, used as antihypertensive and sedative. 

8. Define cardiac glycoside with example. 
Cardiac glycosides are compounds affecting heart muscles. Example: Digoxin from Digitalis purpurea. 

9. What is the difference between extraction and extract? 
Extraction is the process of isolating active constituents. Extract is the concentrated preparation obtained after extraction. 

10. What is the medicinal use of Artemisinin? 
Artemisinin is used for the treatment of malaria, especially caused by Plasmodium falciparum. 

 

11. Define alkaloid with example. 
Alkaloids are nitrogen-containing basic compounds found in plants. Example: Morphine from Papaver somniferum. 

12. Write source and chemical constituents of cinnamon. 
Source: Cinnamomum zeylanicum. Constituents: Cinnamaldehyde, eugenol. 

13. Enlist methods of extraction of volatile oil. 
Methods: Steam distillation, hydro-distillation, expression, and solvent extraction. 

14. Define extraction. 
Extraction is a process to separate active plant constituents from crude drugs using suitable solvents. 

15. Write source and utilization of podophyllotoxin. 
Source: Podophyllum hexandrum. Use: Anticancer agent, used in treatment of warts and testicular cancer. 

 

16. Define anthraquinone glycoside with example. 
These are glycosides containing anthraquinone aglycone. Example: Sennosides from Cassia angustifolia. 

17. What are applications of amino acid pathway? 
Used in biosynthesis of alkaloids, glucosinolates, and some antibiotics. 

18. Write source and uses of belladonna. 
Source: Atropa belladonna. Use: Anticholinergic, antispasmodic, mydriatic (due to atropine). 

19. Write down identification test for alkaloid. 
Dragendorff’s reagent gives orange-red precipitate with alkaloids. 

20. Define primary and secondary metabolite. 
Primary metabolites are essential for growth (e.g., amino acids). Secondary metabolites are not essential but have pharmacological effects (e.g., alkaloids). 

 

21. Write the biological source and chemical constituents of cinnamon bark. 
Source: Cinnamomum zeylanicum. Constituents: Cinnamaldehyde, eugenol, tannins. 

22. Define chromatography. 
Chromatography is a technique used to separate components of a mixture using stationary and mobile phases. 

23. Define secondary metabolites with examples. 
Compounds not directly involved in growth but show biological activity. Examples: Alkaloids, glycosides. 

24. Define cardiac glycosides with examples. 
Cardiac glycosides are plant-derived compounds enhancing heart contractility. Example: Digoxin from Digitalis purpurea. 

25. Write the function of radioactive isotopes. 
Used in tracer studies, metabolic pathways, and diagnosis of diseases in radiopharmaceuticals. 

 

26. Write biological source and active constituents of drug act as antihypertensive. 
Source: Rauwolfia serpentina. Constituents: Reserpine, ajmaline. 

27. How the analysis of crude drugs possible? 
Through organoleptic, microscopic, chemical, physical, and biological evaluation methods. 

28. Write the general chemical test for alkaloids. 
Mayer’s, Dragendorff’s, Wagner’s, and Hager’s tests are used for alkaloid detection. 

29. How pale catechu differentiated from black catechu on the basis of biological source? 
Pale catechu: Uncaria gambir; Black catechu: Acacia catechu. 

30. What is the end product of acetate pathways? 
Terpenoids and fatty acids are end products of the acetate (polyketide) pathway. 

 

31. What are iridoids? Give their therapeutic uses. 
Iridoids are monoterpenoid compounds with anti-inflammatory and hepatoprotective activities. 

32. Give the methods for identification of alkaloids. 
Use of reagents like Dragendorff’s, Mayer’s, Hager’s, and Wagner’s. 

33. Give commercial applications of tannins. 
Used in tanning leather, dyeing, astringent preparations, and as antioxidants. 

34. Give chemical constituents and uses of dioscorea. 
Constituent: Diosgenin. Uses: Precursor for steroidal drugs and contraceptives. 

35. Write the method of estimation of caffeine. 
Caffeine is estimated by UV spectrophotometry or HPLC. 

 

36. Classify glycosides giving suitable examples. 
Types: Anthraquinone (Senna), Cardiac (Digitalis), Saponin (Liquorice), Cyanogenic (Bitter almond), Isothiocyanate (Mustard). 

37. Give chemical structure of any two plant metabolites produced via shikimic acid pathways. 
Examples: Quercetin, Gallic acid. (Structures drawn in exams) 

38. Name the methods used for purification of crude drugs. 
Methods: Recrystallization, distillation, chromatography. 

39. Give official source and uses of forskolin. 
Source: Coleus forskohlii. Uses: Treatment of glaucoma, hypertension, asthma. 

40. Write methods for isolation of volatile oils from crude drugs. 
Steam distillation, hydro-distillation, solvent extraction, and expression. 

 

41. Where are proto alkaloids? 
Protoalkaloids are derived from amino acids but with nitrogen not in a heterocyclic ring. Example: Ephedrine. 

42. Give uses of Forskolin. 
Used as bronchodilator, anti-glaucoma, cardiotonic, and vasodilator. 

43. Explain NPHPLC and RPHPLC. 
NPHPLC: Normal Phase HPLC uses polar stationary phase. RPHPLC: Reverse Phase HPLC uses non-polar stationary phase. 

44. What is biological source and uses of podophyllotoxin? 
Source: Podophyllum hexandrum. Uses: Anticancer and antiviral agent. 

45. Explain VITALI – MORIN test. 
Test for tropane alkaloids. Drug gives violet color with fuming HNO₃ and alcoholic KOH. 

 

46. Draw the structure of Morphine and write its uses. 
Morphine structure (refer textbook); Uses: Analgesic for severe pain, sedative. 

47. What is spectroscopy? 
Spectroscopy is the study of interaction between matter and electromagnetic radiation. 

48. Write chemical tests for glycosides. 
Legal’s test (for cardiac), Borntrager’s test (for anthraquinone), Keller-Killiani test. 

49. What is the biological source and uses of periwinkle? 
Source: Catharanthus roseus. Uses: Anticancer agent (vincristine, vinblastine). 

50. Write chemical constituents of Aloe. 
Constituents: Barbaloin, aloin, aloe-emodin, anthraquinone glycosides. 

 

51. Give the biological source of Clove and Tea. 
Clove: Syzygium aromaticum. Tea: Camellia sinensis. 

52. Draw the structure of Digitoxin and Digoxin. 
Refer textbook for structures; both are cardiac glycosides. 

53. Classify cardiac Glycosides. 
Types: Cardenolides (Digitalis), Bufadienolides (Squill). Classified by aglycone part. 

54. Give the commercial application of Fennel and Gentian. 
Fennel: Carminative, flavoring agent. Gentian: Bitter tonic, digestive stimulant. 

55. Give the chemical class and use of Ginger and Bitter Almond. 
Ginger: Terpenoids; antiemetic. Bitter Almond: Cyanogenic glycosides; expectorant (toxic in large doses). 

 

56. Give the utilization of following phytoconstituents: i) Sennoside ii) Diosgenin 
i) Sennoside: Laxative 
ii) Diosgenin: Precursor for steroidal drugs 

57. Name any two phytoconstituents present in Curcumin and their uses. 
Curcumin and demethoxycurcumin; used as antioxidant, anti-inflammatory agents. 

58. Define Biogenetic studies. 
Study of biosynthetic pathways involved in formation of secondary metabolites in plants. 

59. Write down the biological source of Guggul and Cinnamon. 
Guggul: Commiphora mukul. Cinnamon: Cinnamomum zeylanicum. 

60. Give the commercial application of Catechu and Taxus. 
Catechu: Astringent, used in mouthwash. Taxus: Source of paclitaxel, an anticancer agent. 

 

61. Define term alkaloids. 
Alkaloids are basic, nitrogen-containing organic compounds derived from plants with pharmacological effects. 

62. Enlist various chemical tests for digitalis. 
Keller-Killiani test, Legal’s test, Baljet’s test for cardiac glycosides. 

63. Give biological source and uses of senna. 
Source: Cassia angustifolia. Uses: Stimulant laxative due to sennosides. 

64. Define extraction. 
Extraction is the separation of soluble active constituents from a drug using a solvent. 

65. Write chemical constituents and uses of Rauwolfia. 
Constituents: Reserpine, ajmaline. Uses: Antihypertensive, tranquilizer. 

 

66. Write biological source and chemical constituents of clove. 
Source: Syzygium aromaticum. Constituents: Eugenol, caryophyllene. 

67. Classify resins. 
Types: Oleoresins, gum resins, oleo-gum resins, balsams, and pure resins. 

68. Write adulterants of senna. 
Adulterants: Cassia tora, Cassia obtusifolia, and stems of senna. 

69. Write chemical test for purine alkaloids. 
Murexide test: Purple color indicates caffeine/theobromine. 

70. Enlist methods for extraction of volatile oils. 
Steam distillation, hydro-distillation, expression, and solvent extraction. 

 

 

 

 

 

Pharmacognosy and Phytochemistry II Short Question Answer {5 Marks} 

 

1. Write about the methods used in isolation and identification of Curcumin or Atropine. 

Isolation of Curcumin: 
Curcumin is a yellow pigment obtained from the rhizomes of Curcuma longa (turmeric). 
Method: 

• Solvent Extraction: Dried and powdered turmeric is subjected to Soxhlet extraction using ethanol or acetone. 

• Filtration and Concentration: The extract is filtered and concentrated under reduced pressure to obtain a crude extract. 

• Purification: Curcumin is purified using column chromatography over silica gel, using a solvent system like chloroform:methanol (95:5). 

Identification of Curcumin: 

• UV-Vis Spectroscopy: Curcumin shows absorption maxima around 420–430 nm. 

• TLC: Mobile phase such as chloroform:ethyl acetate:methanol (5:4:1) is used. Curcumin gives a yellow band. 

• HPLC: Retention time and peak area are used for quantification. 

Isolation of Atropine: 
Atropine is isolated from Atropa belladonna or Datura species. 
Method: 

• Extraction: Dried leaf or root is macerated with acidic water (e.g., dilute HCl). 

• Filtration and Basification: Filtrate is made alkaline with ammonia, and atropine is extracted with chloroform. 

• Purification: Chloroform layer is dried and evaporated to obtain crude atropine, followed by recrystallization. 

Identification of Atropine: 

• Color Reactions: Vitali-Morin test gives violet color. 

• TLC/HPLC: Rf value and retention time confirm identity. 

• UV Spectroscopy: Absorbance at 258 nm. 

Both compounds are pharmacologically active and are analyzed further through spectroscopic techniques for quality control and standardization. 

2. Write about the methods used in insertion of radio labelled isotopes in plants. 

Radioactive isotopes are widely used in plant studies to trace the biosynthetic pathways of phytoconstituents. The insertion or incorporation of radio-labelled isotopes into plants is a sophisticated method involving the administration of isotopes like ¹⁴C, ³H, ³²P, or ¹⁵N into plant systems. The commonly used techniques include: 

1. Feeding Technique: 

• A radio-labelled precursor (like ¹⁴C-glucose or ¹⁴C-acetate) is dissolved in water and administered to the plant via roots or leaves. 

• The solution is absorbed and metabolized by the plant, and the labelled atoms become part of secondary metabolites. 

2. Leaf Absorption: 

• Involves spraying the radioactive solution directly onto the leaf surface. 

• The labelled compound is absorbed through the stomata or cuticle and incorporated into the plant’s metabolic network. 

3. Injection Method: 

• The radio-labelled compound is directly injected into the stem, petiole, or fruit. 

• This ensures targeted delivery and localized metabolic tracking. 

4. Root Dipping or Hydroponic Method: 

• Seedlings or plant roots are immersed in nutrient solution containing radioactive tracers. 

• This allows uniform and systemic distribution of isotopes. 

5. Photosynthetic Labelling: 

• Plants are exposed to ¹⁴CO₂ in a closed chamber. 

• During photosynthesis, carbon dioxide is assimilated, and labelled carbon is incorporated into sugars and other metabolites. 

Detection and Analysis: 
After insertion, radioactivity is traced in plant tissues using: 

• Autoradiography 

• Liquid scintillation counting 

• Radiochemical isolation and chromatography 

Applications: 
Used for tracing metabolic pathways, locating metabolite accumulation, and identifying biosynthetic intermediates in medicinal plants. 

3. Describe shikimic acid pathway. 

The shikimic acid pathway is a crucial biosynthetic route in plants and microorganisms that leads to the formation of aromatic compounds, especially secondary metabolites like alkaloids, flavonoids, tannins, and lignins. 

Steps in the Shikimic Acid Pathway: 

1. Condensation Reaction: 

1. The pathway begins with the condensation of phosphoenolpyruvate (PEP) from glycolysis and erythrose-4-phosphate (E4P) from the pentose phosphate pathway. 

2. This reaction forms 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP). 

2. Cyclization and Conversion: 

1. DAHP undergoes a series of reactions forming shikimic acid via intermediates such as 3-dehydroquinic acid and 3-dehydroshikimic acid. 

3. Formation of Chorismic Acid: 

1. Shikimic acid is converted to chorismic acid, a crucial branching point compound. 

4. Branching Pathways: 

1. From chorismic acid, the pathway leads to synthesis of: 

1. Phenylalanine and Tyrosine (via prephenic acid) 

2. Tryptophan (via anthranilic acid) 

3. Secondary metabolites such as flavonoids, tannins, lignin, coumarins, and alkaloids. 

Importance in Pharmacognosy: 

• Biosynthesis of Aromatic Compounds: 
  Many plant drugs owe their activity to phenolic structures derived from this pathway. 

• Examples of Metabolites: 

• Quinine, morphine, curcumin, gallic acid, caffeic acid, and vanillin are synthesized via intermediates of the shikimic acid pathway. 

• Industrial Applications: 

• Shikimic acid itself is a precursor in the synthesis of the antiviral drug oseltamivir (Tamiflu). 

This pathway does not exist in animals, making it an excellent target for herbicides and antibiotics. 

4. Write isolation and identification of caffeine. 

Caffeine is a purine alkaloid found in various plants such as Camellia sinensis (tea), Coffea arabica (coffee), and Theobroma cacao (cocoa). It is a central nervous system stimulant and diuretic. 

 

Isolation of Caffeine: 

1. Sample Preparation: 

• Dried tea leaves or coffee beans are powdered and boiled with water. 

2. Extraction: 

• The aqueous extract is filtered and made alkaline using sodium carbonate or ammonia. 

• Then, it is extracted using chloroform or dichloromethane in a separating funnel. 

3. Concentration: 

• The organic layer is separated and evaporated under reduced pressure to obtain crude caffeine. 

4. Purification: 

• Recrystallization is done using hot water or ethanol to obtain pure caffeine crystals. 

 

Identification of Caffeine: 

1. Chemical Tests: 

• Murexide Test: The residue is treated with nitric acid and then evaporated. A few drops of ammonia give a purple color, confirming caffeine. 

• Tannic Acid Test: Aqueous caffeine solution gives a precipitate with tannic acid. 

2. Thin Layer Chromatography (TLC): 

• Solvent system: Chloroform: acetone (9:1). 

• Rf value of caffeine is compared with standard. 

3. UV Spectroscopy: 

• Caffeine shows absorption maxima at 273 nm in UV spectrum. 

4. HPLC Analysis: 

• Retention time and peak area are used for quantitative analysis. 

• Mobile phase: Methanol:Water or Acetonitrile:Buffer system. 

 

Conclusion: 

Isolation and identification of caffeine is significant for quality control in herbal formulations, beverages, and pharmaceutical preparations. Spectroscopic and chromatographic techniques ensure purity and standardization. 

5. Write the biological source and active constituents of drug produce hypolipidemic, antiseptic, dental analgesic, parasympatholytic and astringent activity. 

This question requires examples of plant-derived drugs exhibiting specific pharmacological activities. Below is a compilation based on each mentioned activity: 

 

1. Hypolipidemic Activity: 

• Drug: Commiphora mukul (Guggul) 

• Biological Source: Oleo-gum-resin from the bark of Commiphora mukul (Burseraceae). 

• Active Constituents: Guggulsterones Z and E. 

• Use: Reduces LDL cholesterol and triglycerides. 

 

2. Antiseptic Activity: 

• Drug: Syzygium aromaticum (Clove) 

• Biological Source: Dried flower buds of Syzygium aromaticum (Myrtaceae). 

• Active Constituents: Eugenol. 

• Use: Acts as antiseptic, antifungal, and antimicrobial. 

 

3. Dental Analgesic: 

• Drug: Clove (Syzygium aromaticum) 

• Biological Source: Same as above. 

• Active Constituents: Eugenol. 

• Use: Provides local analgesic effect in toothache and dental infections. 

 

4. Parasympatholytic Activity: 

• Drug: Atropa belladonna 

• Biological Source: Leaves and roots of Atropa belladonna (Solanaceae). 

• Active Constituents: Atropine, hyoscyamine, scopolamine. 

• Use: Used as anticholinergic agent to reduce smooth muscle spasms and as mydriatic. 

 

5. Astringent Activity: 

• Drug: Acacia catechu (Black Catechu) 

• Biological Source: Heartwood extract of Acacia catechu (Fabaceae). 

• Active Constituents: Catechin, tannic acid. 

• Use: Used for treating diarrhea, sore throat, and skin conditions. 

 

These natural drugs provide valuable pharmacological activities and are widely used in traditional and modern medicine. Their identification and standardization are essential in ensuring therapeutic efficacy. 

6. Define HPLC and write its application in the analysis of two phytoconstituents. 

High Performance Liquid Chromatography (HPLC) is a powerful analytical technique used to separate, identify, and quantify components in a mixture. It uses a liquid mobile phase and a solid stationary phase under high pressure, allowing high resolution and sensitivity. 

 

Principle of HPLC: 

Separation is based on the differential affinity of compounds toward the stationary phase and their solubility in the mobile phase. Components with stronger interaction with the stationary phase elute slower, leading to separation. 

 

Components of HPLC System: 

1. Pump: Delivers mobile phase at high pressure. 

2. Injector: Introduces the sample. 

3. Column: Contains stationary phase (usually C18 silica). 

4. Detector: UV, PDA, or fluorescence detectors. 

5. Recorder/Software: Provides chromatograms and quantitative data. 

 

Applications in Phytoconstituent Analysis: 

1. Analysis of Curcumin: 

• Plant: Curcuma longa 

• Mobile Phase: Acetonitrile:Water (60:40) 

• Detection: UV at 420 nm 

• Use: Quantification of curcuminoids for standardization of turmeric extracts. 

2. Analysis of Reserpine: 

• Plant: Rauwolfia serpentina 

• Mobile Phase: Methanol:Water with phosphate buffer 

• Detection: UV at 268 nm 

• Use: Quality control and dosage standardization in antihypertensive formulations. 

 

Advantages of HPLC: 

• High sensitivity and specificity. 

• Suitable for non-volatile and thermolabile compounds. 

• Rapid and reproducible results. 

HPLC is essential in herbal drug research for ensuring identity, purity, and concentration of active principles. 

7. Write about the method used for estimation of diosgenin active constituent. 

Diosgenin is a steroidal sapogenin primarily obtained from the tubers of Dioscorea species and is widely used in the semi-synthesis of corticosteroids and contraceptive hormones. 

 

Estimation Methods for Diosgenin: 

1. UV Spectrophotometric Method: 

• Extraction: 

• Dried Dioscorea tubers are powdered and hydrolyzed with dilute hydrochloric acid to break down saponins into diosgenin. 

• The mixture is then extracted with an organic solvent such as chloroform or ether. 

• Detection: 

• The extract is concentrated and analyzed using a UV spectrophotometer at absorption maxima ~296 nm. 

• The absorbance is compared with that of standard diosgenin to determine content. 

 

2. High Performance Liquid Chromatography (HPLC): 

• Extraction: 

• Similar to above, followed by filtration and concentration. 

• Chromatographic Conditions: 

• Stationary Phase: C18 column 

• Mobile Phase: Methanol:Water (90:10) 

• Detection Wavelength: 203–210 nm 

• Quantification: 

• Based on the retention time and area under curve compared with standard diosgenin. 

 

3. Gas Chromatography (GC): 

• After derivatization (e.g., silylation), diosgenin can be estimated via GC with a flame ionization detector (FID). 

 

Applications: 

• Used to determine diosgenin content in crude drug samples for standardization. 

• Assures quality control in steroidal drug manufacturing. 

 

These estimation techniques are essential to monitor diosgenin levels in raw materials, aiding pharmaceutical industries in hormone precursor production. 

8. Write applications of radioactive isotopes in biosynthetic pathways. 

Radioactive isotopes play a vital role in the study of biosynthetic pathways in medicinal plants. These isotopes help in tracing the origin, sequence, and intermediates in the synthesis of primary and secondary metabolites. 

 

Commonly Used Radioactive Isotopes: 

• Carbon-14 (¹⁴C) 

• Tritium (³H) 

• Phosphorus-32 (³²P) 

• Sulphur-35 (³⁵S) 

• Nitrogen-15 (¹⁵N) (stable isotope, also used in tracer studies) 

 

Applications in Biosynthetic Pathway Studies: 

1. Tracer Studies: 

• Radio-labelled precursors (e.g., ¹⁴C-acetate, ¹⁴C-glucose) are administered to plants. 

• Their incorporation into specific phytoconstituents like alkaloids, flavonoids, terpenoids, and glycosides is tracked. 

2. Determining Pathway Sequences: 

• Helps identify the order of steps and intermediates in complex biosynthetic pathways such as the Shikimic acid, Mevalonic acid, and Amino acid pathways. 

3. Precursor-Product Relationship: 

• Confirms which metabolite serves as a precursor in the synthesis of another compound. 

• Example: ¹⁴C-glucose incorporated into lignin confirms phenylpropanoid pathway involvement. 

4. Elucidation of Active Sites: 

• Localizes sites within plants where specific biosynthetic reactions occur. 

5. Studying Enzymatic Reactions: 

• Radioactive isotopes help determine enzyme activity and reaction rates by tracking labelled substrates/products. 

 

Detection Techniques: 

• Autoradiography 

• Liquid Scintillation Counting 

• Radiometric Chromatography 

 

Conclusion: 

Radioisotopes are essential for modern pharmacognostic research, enabling scientists to understand plant metabolism at molecular levels and aiding in drug discovery. 

9. Write biological source, chemical constituents and medicinal uses of drug comes under oleo-gum-resin. 

Oleo-gum-resins are natural exudates from certain plants that contain a combination of volatile oils (oleo), water-soluble gums, and alcohol-soluble resins. These are widely used in traditional and modern medicine. 

 

Example: Asafoetida 

• Biological Source: 
  Oleo-gum-resin obtained by incision from the root of Ferula foetida, Ferula asafoetida (Family: Umbelliferae). 

• Chemical Constituents: 

• Volatile oil (4–20%) – contains sulfur compounds like ferulic acid, disulfides (responsible for pungent smell). 

• Resin (40–64%) – includes asaresinotannol and other phenolic compounds. 

• Gum (20–25%) – composed of glucose, galactose, arabinose. 

• Small quantities of ferulic acid and other free acids. 

 

Medicinal Uses: 

1. Carminative and Antispasmodic: 
   Relieves flatulence, bloating, and intestinal cramps. 

2. Digestive Aid: 
   Stimulates secretion of digestive juices and helps treat indigestion. 

3. Expectorant and Respiratory Uses: 
   Used in cough, bronchitis, and asthma due to its expectorant and anti-inflammatory action. 

4. Antimicrobial and Antiviral: 
   Exhibits antibacterial and antiviral properties; used in traditional medicine for infections. 

5. Emmenagogue: 
   Stimulates menstrual flow and used in treatment of amenorrhea. 

 

Other Examples of Oleo-gum-resins: 

• Myrrh: (Commiphora molmol) – Used as antiseptic and in oral care. 

• Guggul: (Commiphora mukul) – Used in hypolipidemic and anti-inflammatory formulations. 

 

These resins are important in Ayurvedic, Unani, and modern pharmacopeias due to their multi-functional therapeutic properties. 

10. Discuss industrial production, estimation and utilization of diosgenin. 

Diosgenin is a naturally occurring steroidal sapogenin, primarily obtained from tubers of Dioscorea species. It serves as a key intermediate for the synthesis of various steroidal drugs including corticosteroids, sex hormones, and oral contraceptives. 

 

1. Industrial Production of Diosgenin: 

a. Raw Material Collection: 

• Tubers of Dioscorea deltoidea, Dioscorea floribunda, and other related species are harvested and dried. 

b. Hydrolysis Process: 

• Tubers are powdered and subjected to acid hydrolysis using dilute HCl or H₂SO₄. 

• This breaks down the saponins to release free diosgenin. 

c. Extraction: 

• Hydrolyzed material is neutralized and extracted with organic solvents like petroleum ether or chloroform. 

d. Purification: 

• Extract is filtered, concentrated, and recrystallized using alcohol to yield pure diosgenin. 

 

2. Estimation of Diosgenin: 

• UV Spectroscopy: 
  Absorption maxima around 296 nm. 

• HPLC: 
  Mobile phase of methanol:water with UV detection at 203–210 nm. 

• TLC/Densitometry: 
  Spotting of sample alongside standard diosgenin helps quantify the content. 

 

3. Utilization of Diosgenin: 

• Synthesis of Steroidal Drugs: 
  Diosgenin serves as a precursor for industrial synthesis of: 

• Corticosteroids (e.g., hydrocortisone) 

• Progesterone (used in contraceptives) 

• Androgens and estrogens 

• Research and Biotechnological Applications: 
  Used as a reference standard in plant studies and biotechnology research involving steroidal pathways. 

• Pharmaceutical Use: 
  Though not pharmacologically active itself, it’s vital for hormone-based drug synthesis. 

 

Diosgenin remains a critical phytoconstituent in both pharmaceutical manufacturing and phytochemical research. 

11. Write pharmacognostical profile of Digitalis. 

Digitalis refers to the dried leaves of Digitalis purpurea and Digitalis lanata, known for their potent cardiac glycosides used in the treatment of heart diseases. 

 

1. Biological Source: 

• Digitalis purpurea (Purple foxglove) and Digitalis lanata (Woolly foxglove), Family: Scrophulariaceae. 

 

2. Morphological Features: 

• Leaves: Simple, sessile, ovate-lanceolate with finely toothed margins and acute apex. 

• Size: 10–35 cm long and 4–10 cm wide. 

• Surface: Pubescent, especially in D. lanata. 

• Color: Dried leaves appear greenish-brown. 

• Odor: Slight. 

• Taste: Bitter. 

 

3. Microscopic Characteristics: 

• Epidermis: Uniseriate with anisocytic stomata, more on the lower surface. 

• Trichomes: Multicellular covering and glandular types. 

• Mesophyll: Dorsiventral leaf with palisade and spongy parenchyma. 

• Vascular Bundles: Prominent midrib with bicollateral bundles. 

 

4. Chemical Constituents: 

• Cardiac glycosides: 

• From D. purpurea: Purpurea glycoside A and B → converted to digitoxin. 

• From D. lanata: Lanatosides A, B, C, D, E → digoxin (from lanatoside C). 

• Flavonoids, saponins, and polysaccharides. 

 

5. Medicinal Uses: 

• Cardiotonic – strengthens heart contractions. 

• Treats congestive heart failure, atrial fibrillation. 

• Narrow therapeutic index; requires precise dosing. 

 

6. Adulterants: 

• Inula, Verbascum, and Symphytum leaves are sometimes mixed but can be identified microscopically. 

 

Conclusion: 

Digitalis is a classic example of a potent, life-saving phytomedicine that demands accurate pharmacognostic evaluation for quality control and safe use. 

12. Write application of chromatography in crude drug isolation, purification and identification. 

Chromatography is a powerful analytical and preparative technique used in Pharmacognosy and Phytochemistry to separate, purify, and identify plant constituents from crude drug extracts. 

 

Applications of Chromatography: 

1. Isolation of Crude Drugs: 

• Column Chromatography: 

• Used to isolate alkaloids, flavonoids, terpenoids, and glycosides from plant extracts. 

• Based on differential affinity of compounds towards stationary and mobile phases. 

• Preparative TLC (Thin Layer Chromatography): 

• Enables separation and isolation of phytoconstituents in small quantities for further analysis. 

• HPLC (High Performance Liquid Chromatography): 

• Used for precise isolation of active principles like curcumin, reserpine, digoxin, etc. 

 

2. Purification of Phytoconstituents: 

• Chromatography removes unwanted impurities from crude drug extracts. 

• Flash Chromatography is used for rapid purification in industrial settings. 

• Recrystallization after chromatographic separation increases compound purity. 

 

3. Identification of Constituents: 

• TLC and HPTLC: 

• Used to create a chemical fingerprint. 

• Rf values are compared with standards to identify compounds. 

• HPLC and GC (Gas Chromatography): 

• Retention time and peak area are matched with reference compounds. 

• Spectral Integration: 

• Combined with UV, MS, or NMR to identify structure and purity. 

 

Examples: 

• Identification of alkaloids in Rauwolfia. 

• Separation of glycosides in Digitalis. 

• Analysis of essential oils via GC. 

 

Conclusion: 

Chromatography plays a central role in herbal drug standardization by ensuring compound identity, purity, and concentration, supporting quality control and regulatory compliance. 

13. Write isolation, identification and analysis of menthol and citral. 

Menthol and Citral are important constituents of essential oils obtained from Mentha and Cymbopogon species respectively. Both are used in the pharmaceutical, cosmetic, and food industries. 

 

Isolation: 

A. Menthol 

• Source: Mentha arvensis or Mentha piperita (Family: Lamiaceae) 

• Method: 

• Steam Distillation of mint leaves to obtain mint oil. 

• Oil is cooled to crystallize menthol. 

• Crystals are separated by filtration and recrystallized for purity. 

B. Citral 

• Source: Cymbopogon citratus (Lemongrass) (Family: Poaceae) 

• Method: 

• Steam Distillation of lemongrass yields essential oil containing citral. 

• Citral is separated by fractional distillation due to its lower boiling point. 

 

Identification: 

Menthol: 

• Melting Point: 41–44°C. 

• Color Reaction: Menthol gives violet color with nitric acid and nitrous acid. 

• TLC: Rf value compared with standard. 

• IR Spectroscopy: Characteristic OH and aliphatic peaks. 

Citral: 

• Chemical Test: Positive with 2,4-Dinitrophenylhydrazine (forms yellow precipitate indicating aldehyde group). 

• TLC/HPLC: Confirms presence via retention factor/time. 

• IR Spectroscopy: Peaks for aldehyde and C=C bonds. 

 

Analysis: 

• GC (Gas Chromatography): 

• Used for quantitative estimation and purity analysis. 

• Menthol and citral are detected by retention time. 

• UV Spectroscopy: 

• Citral shows absorption due to conjugated system (around 235–240 nm). 

• Menthol does not absorb significantly in UV-visible range. 

 

Conclusion: 

Menthol and citral are economically and therapeutically valuable phytoconstituents, and their identification and purity are essential for formulation quality. 

14. Write a note on utilization of radioisotope in biogenetic study. 

Radioisotopes are unstable isotopes of elements that emit radiation and are extensively used in biogenetic studies to trace the synthesis and transformation of biochemical compounds in plants. 

 

Principle: 

Radio-labelled precursors (e.g., ¹⁴C-glucose, ³H-phenylalanine) are introduced into plant systems. As the plant metabolizes the compound, the radioactive atoms become part of newly synthesized metabolites. These are later isolated and analyzed to map the biosynthetic pathway. 

 

Methods of Incorporation: 

• Feeding technique: Administering labelled compounds to roots or leaves. 

• Injection method: Injecting directly into stems or fruits. 

• Photosynthetic labelling: Using ¹⁴CO₂ to trace carbon flow. 

• Hydroponic method: Growing plants in nutrient solutions containing isotopes. 

 

Detection Techniques: 

• Autoradiography: Imaging to locate radioactive compounds in tissues. 

• Liquid scintillation counting: Quantifies radioactivity in isolated compounds. 

• Radiometric chromatography: Combines TLC or HPLC with radioactive detection. 

 

Applications in Biogenetic Studies: 

1. Mapping Pathways: 

1. Helps establish steps in shikimic acid, mevalonate, or amino acid pathways. 

2. Precursor Identification: 

1. Confirms if a compound is a true precursor by tracking its incorporation into a target metabolite. 

3. Metabolite Localization: 

1. Determines in which plant part or tissue synthesis or accumulation occurs. 

4. Rate of Biosynthesis: 

1. By measuring incorporation over time, one can estimate biosynthesis rate. 

 

Conclusion: 

Radioisotopes are invaluable tools in phytochemistry and pharmacognosy. They reveal detailed insights into how medicinally active compounds are synthesized, aiding drug discovery and biosynthetic engineering. 

15. Write source, isolation method, analysis and utilization of atropine. 

Atropine is a tropane alkaloid with anticholinergic (parasympatholytic) properties, used in ophthalmology, anesthesia, and poisoning treatment. 

 

1. Biological Source: 

• Derived from Atropa belladonna, Datura stramonium, and Hyoscyamus niger. 

• Family: Solanaceae. 

• Part used: Leaves and roots. 

 

2. Isolation Method: 

a. Extraction: 

• Dried and powdered plant material is macerated with dilute hydrochloric acid. 

• The mixture is filtered, and the acidic filtrate is basified with ammonia. 

b. Liquid-Liquid Extraction: 

• The alkaloid (in free base form) is extracted using chloroform or ether in a separating funnel. 

c. Purification: 

• The chloroform layer is evaporated to obtain crude atropine. 

• Recrystallization is done using alcohol or ether to get purified atropine. 

 

3. Analysis of Atropine: 

• TLC (Thin Layer Chromatography): 
  Rf value compared with standard in solvent system like chloroform:methanol (9:1). 

• Color Reaction (Vitali-Morin Test): 
  Atropine treated with fuming nitric acid and then with alcoholic KOH gives violet color. 

• HPLC: 
  Used for quantification with UV detection at 258 nm. 

• IR/NMR Spectroscopy: 
  Confirms chemical structure. 

 

4. Utilization: 

• Mydriatic agent: 
  Dilates pupils during eye examinations. 

• Pre-anesthetic: 
  Reduces salivary and bronchial secretions. 

• Antidote: 
  Used in organophosphate and nerve agent poisoning. 

• Antispasmodic: 
  Relieves smooth muscle spasms in GI and urinary tract. 

 

Conclusion: 

Atropine remains a significant tropane alkaloid with diverse medical applications, requiring careful extraction and standardization due to its potent pharmacological effects. 

16. Briefly explain silicic acid pathway. 

The Silicic Acid Pathway is a lesser-known but important biosynthetic route found primarily in certain lower plants (like algae) and higher plants such as grasses and cereals. It involves the uptake and polymerization of monosilicic acid (Si(OH)₄) to form biogenic silica (SiO₂·nH₂O). 

 

1. Source of Silicic Acid: 

• Plants absorb silicon from the soil as monosilicic acid, which is water-soluble and biologically available. 

 

2. Steps of Silicic Acid Pathway: 

a. Absorption: 

• Silicic acid is absorbed by plant roots from soil or nutrient solution. 

b. Translocation: 

• Transported via xylem sap to different plant parts. 

c. Polymerization: 

• In plant tissues, silicic acid undergoes condensation forming amorphous silica (SiO₂) or silica gel. 

d. Deposition: 

• Biogenic silica is deposited in cell walls, epidermis, and trichomes, forming phytoliths (silica bodies). 

 

3. Biological Significance: 

• Mechanical Strength: 
  Silica strengthens cell walls, especially in grasses like rice and bamboo. 

• Defense Mechanism: 
  Acts as a barrier against fungal infections, pests, and herbivores. 

• Structural Role: 
  Provides rigidity to stems and leaves. 

• Water Retention & Stress Tolerance: 
  Improves drought and salinity tolerance by reducing water loss. 

 

4. Pharmacognostical Importance: 

• Phytoliths can be used as taxonomic markers for identifying plant species in powdered crude drugs. 

• Useful in paleobotany for fossil identification. 

 

Conclusion: 

Though not directly involved in secondary metabolite synthesis like the shikimic or mevalonate pathways, the silicic acid pathway is crucial for plant structure, defense, and ecological adaptation, and has applications in pharmacognostic studies. 

17. What is cardiac glycoside? Write the difference between cardenolide and bufadienolide. 

 

Cardiac Glycosides: 

Cardiac glycosides are naturally occurring plant-derived or animal-derived compounds known for their potent effects on cardiac muscles. They increase the force of contraction (positive inotropic effect) and are used in the treatment of congestive heart failure (CHF) and arrhythmias. 

• Structure: Composed of two parts: 

• Aglycone (genin) – steroid nucleus with lactone ring 

• Sugar moiety – improves solubility and bioavailability 

 

Examples of Cardiac Glycoside Drugs: 

• Digitalis (Digitalis purpurea, Digitalis lanata) 

• Strophanthus 

• Nerium oleander 

 

Differences between Cardenolide and Bufadienolide: 

Feature	Cardenolides	Bufadienolides
Lactone Ring	5-membered α,β-unsaturated lactone ring	6-membered doubly unsaturated lactone ring
Occurrence	Mostly in plants (Digitalis, Strophanthus)	Found in toads (Bufo) and some plants (Scilla)
Examples	Digitoxin, Digoxin	Bufalin, Scillaren A
Number of Double Bonds	One double bond in lactone ring	Two conjugated double bonds in lactone ring
UV Absorption	Max around 220–230 nm	Max around 300 nm

 

Conclusion: 

Cardiac glycosides are vital in cardiovascular therapy. Differentiating cardenolides from bufadienolides is important for pharmacological profiling, as their potency and source vary. 

18. Write a note on production, estimation and utilization of taxol. 

Taxol (Paclitaxel) is a highly potent anticancer agent belonging to the diterpenoid class, originally isolated from the bark of the Pacific yew tree (Taxus brevifolia). 

 

1. Production of Taxol: 

A. Natural Source: 

• Derived from the bark and leaves of Taxus brevifolia, Taxus baccata (Family: Taxaceae). 

B. Extraction Method: 

1. Bark or leaves are dried and powdered. 

2. Extracted with organic solvents like methanol or dichloromethane. 

3. The crude extract is partitioned and purified using column chromatography. 

4. Final purification is done by recrystallization or HPLC. 

C. Semi-Synthetic Production: 

• Due to ecological concerns, 10-deacetylbaccatin III from Taxus baccata needles is used as a precursor for semi-synthesis of taxol. 

D. Biotechnological Production: 

• Plant tissue culture and endophytic fungi (e.g., Taxomyces andreanae) have been explored for sustainable production. 

 

2. Estimation of Taxol: 

A. HPLC Method: 

• Column: C18 reverse-phase 

• Mobile phase: Acetonitrile:Water (50:50) 

• Detection: UV at 227 nm 

• Standard curve is prepared using known concentrations of pure taxol. 

B. Spectroscopic Techniques: 

• NMR and IR are used for structural confirmation. 

• Mass Spectrometry is employed for molecular weight determination. 

 

3. Utilization of Taxol: 

• Anticancer Drug: 

• Effective against ovarian, breast, lung, and pancreatic cancers. 

• Works by stabilizing microtubules, inhibiting cell division. 

• Chemotherapeutic Formulations: 

• Marketed as Taxol®, Abraxane®. 

• Used in combination therapies. 

• Research Tool: 

• Used in cell biology studies related to microtubule dynamics. 

 

Conclusion: 

Taxol is a cornerstone in cancer chemotherapy. Due to its complex structure and low natural abundance, its production through semi-synthesis and biotechnology has become essential for pharmaceutical industries. 

19. Write the isolation, identification and analysis of podophyllotoxin or atropine. 

(Answering for Podophyllotoxin) 

 

1. Biological Source: 

• Podophyllotoxin is obtained from the rhizomes and roots of Podophyllum hexandrum (Indian podophyllum) and Podophyllum peltatum (American podophyllum). 

• Family: Berberidaceae 

 

2. Isolation of Podophyllotoxin: 

a. Extraction: 

• Dried and powdered rhizomes are defatted with petroleum ether. 

• Extracted with alcohol (ethanol or methanol) by maceration or Soxhlet extraction. 

b. Concentration and Precipitation: 

• Concentrated alcoholic extract is poured into cold water. 

• Resinous precipitate forms – called podophyllin (contains ~20% podophyllotoxin). 

c. Purification: 

• Podophyllin is treated with solvents like chloroform or acetone. 

• Further purification by recrystallization or column chromatography yields pure podophyllotoxin. 

 

3. Identification of Podophyllotoxin: 

• Chemical Test: 
  Podophyllotoxin gives a brown color with sulfuric acid. 

• TLC (Thin Layer Chromatography): 

• Solvent system: Chloroform:methanol (9:1) 

• Rf value compared with standard. 

• UV Spectroscopy: 
  Shows characteristic absorption at 290–300 nm. 

• Melting Point: 183–185°C (used for preliminary identification). 

 

4. Analysis of Podophyllotoxin: 

• HPLC: 

• Column: C18 

• Mobile phase: Acetonitrile:Water (60:40) 

• Detection at 290 nm for quantification. 

• NMR and IR Spectroscopy: 
  Confirm the presence of characteristic methylene-dioxy and lactone functional groups. 

 

5. Utilization: 

• Antimitotic agent: 
  Inhibits microtubule formation. Basis for semi-synthetic drugs like etoposide and teniposide. 

• Antiviral: 
  Used topically to treat genital warts. 

 

Conclusion: 

Podophyllotoxin is a potent phytochemical with anticancer and antiviral properties, and its extraction and analysis require precise techniques for therapeutic standardization. 

20. Define resins and write biological source, uses and commercial application of Digitalis or Bitter Almond. 

(Answering for Bitter Almond) 

 

Definition of Resins: 

Resins are amorphous, non-crystalline, solid or semi-solid organic substances, typically formed as plant exudates. They are insoluble in water but soluble in alcohol, ether, and other organic solvents. Resins are secreted in specialized plant ducts and serve defensive, healing, or protective roles in plants. 

 

Types of Resins (Classification): 

• Oleoresins – Resin + volatile oil (e.g., Ginger) 

• Gum resins – Resin + gum (e.g., Myrrh) 

• Oleo-gum-resins – Resin + gum + volatile oil (e.g., Asafoetida) 

• Balsams – Resin with cinnamic/benzoic acid (e.g., Benzoin) 

 

Bitter Almond (Prunus amygdalus var. amara): 

1. Biological Source: 

• Dried ripe seeds of Prunus amygdalus var. amara (Family: Rosaceae) 

2. Chemical Constituents: 

• Contains fixed oil (40–50%) 

• Amygdalin – A cyanogenic glycoside 

• Emulsin – Enzyme that hydrolyzes amygdalin to produce benzaldehyde and hydrogen cyanide (HCN) 

 

3. Medicinal Uses: 

• Expectorant and antitussive (due to benzaldehyde). 

• Used in flavoring agents (trace amounts only). 

• Skin care – Bitter almond oil is used externally for softening and soothing skin. 

 

4. Commercial Applications: 

• Essential Oil: 
  Used in cosmetics, perfumery, and soaps (after detoxifying HCN). 

• Pharmaceutical Industry: 
  Source of benzaldehyde and almond flavor. 

• Caution: 
  Due to cyanogenic content, ingestion in large amounts is toxic. 

 

Conclusion: 

Bitter almond is pharmaceutically and commercially valuable. Resins, including derivatives from bitter almond, play crucial roles in flavoring, medicines, and industrial applications. 

21. Describe amino acid pathway. 

The Amino Acid Pathway is a major biogenetic route in plants that leads to the formation of a variety of secondary metabolites, especially alkaloids, phenolics, and glucosinolates. 

 

Key Features of the Amino Acid Pathway: 

• Precursors: Primary metabolites like amino acids such as phenylalanine, tyrosine, tryptophan, lysine, ornithine, and histidine serve as starting materials. 

• Enzymes involved in this pathway catalyze the conversion of amino acids into complex bioactive compounds. 

 

Important Products and Their Biosynthetic Origin: 

1. Phenylalanine Pathway: 

• Leads to biosynthesis of: 

• Flavonoids (e.g., quercetin) 

• Tannins 

• Lignin 

• Involves phenylpropanoid pathway which converts phenylalanine to cinnamic acid (via phenylalanine ammonia lyase, PAL). 

2. Tryptophan Pathway: 

• Produces indole alkaloids such as: 

• Vincristine, Reserpine, Ajmalicine 

• Tryptophan → Tryptamine → Indole alkaloids 

3. Tyrosine Pathway: 

• Leads to: 

• Isoquinoline alkaloids (e.g., morphine, papaverine) 

• Catecholamines (dopamine, epinephrine) 

• Tyrosine → Dopamine → Benzylisoquinoline alkaloids 

4. Lysine & Ornithine Pathway: 

• Responsible for the synthesis of tropane alkaloids like: 

• Atropine, Hyoscyamine, Scopolamine 

• Via intermediates like putrescine and N-methylpyrrolinium. 

 

Pharmacological Importance: 

• Many drugs are derived from these pathways such as: 

• Morphine (analgesic) 

• Atropine (anticholinergic) 

• Vinblastine (anticancer) 

 

Conclusion: 

The amino acid pathway is central to plant secondary metabolism, especially for pharmacognostic and phytopharmaceutical studies. It gives rise to structurally diverse and medicinally important compounds widely used in modern therapy. 

22. Write in short about isolation of terpenoids. 

Terpenoids (also known as isoprenoids) are a large and diverse class of naturally occurring organic compounds derived from isoprene (C₅H₈) units. They include essential oils, resins, carotenoids, and steroids. 

 

Sources of Terpenoids: 

• Essential oils from Mentha, Cymbopogon, Eucalyptus 

• Resins from Boswellia, Commiphora 

• Plant parts used: Leaves, bark, flowers, and oleoresins 

 

Steps for Isolation of Terpenoids: 

1. Collection and Preparation: 

• Plant material is dried and powdered to increase surface area for extraction. 

2. Extraction Methods: 

a. Steam Distillation: 

• Commonly used for volatile terpenoids (e.g., menthol, limonene). 

• Plant material is steam-distilled and essential oil collected. 

b. Solvent Extraction: 

• Organic solvents like hexane, ether, or chloroform are used to extract non-volatile terpenoids (e.g., boswellic acid). 

• The extract is concentrated using a rotary evaporator. 

c. Supercritical Fluid Extraction (SFE): 

• Uses supercritical CO₂ as the solvent. 

• Offers higher selectivity, efficiency, and thermal stability. 

 

3. Purification: 

a. Column Chromatography: 

• Separates terpenoids using silica gel columns and solvents of increasing polarity. 

b. Thin Layer Chromatography (TLC): 

• Used for rapid screening and semi-quantitative analysis. 

c. Recrystallization: 

• Applied for solid terpenoids to increase purity. 

 

4. Identification & Analysis: 

• GC-MS (Gas Chromatography-Mass Spectrometry): For volatile terpenoids. 

• HPLC: For non-volatile terpenoids. 

• UV, IR, NMR Spectroscopy: For structural confirmation. 

 

Conclusion: 

Isolation of terpenoids requires careful selection of extraction and purification methods based on their volatility and solubility. These compounds have important roles in pharmaceuticals, cosmetics, and the food industry. 

23. Write the estimation and utilization of artemisinin. 

Artemisinin is a sesquiterpene lactone with a peroxide bridge, derived from Artemisia annua (Family: Asteraceae). It is a potent antimalarial agent, especially effective against Plasmodium falciparum. 

 

1. Estimation of Artemisinin: 

a. High-Performance Liquid Chromatography (HPLC): 

• Column: C18 reverse-phase 

• Mobile Phase: Methanol:Water or Acetonitrile:Water 

• Detection: UV at 210–254 nm 

• Provides accurate quantification of artemisinin content in plant extract or formulations. 

b. Gas Chromatography (GC): 

• Suitable for volatile derivatives of artemisinin (e.g., artemether, artesunate). 

• Coupled with mass spectrometry (GC-MS) for purity and structure confirmation. 

c. Colorimetric Method: 

• Involves reaction with sodium hydroxide followed by color change (less preferred due to lower specificity). 

d. Bioassay: 

• In vitro or in vivo assays using Plasmodium species to assess biological activity. 

 

2. Utilization of Artemisinin: 

a. Antimalarial Use: 

• Most effective against chloroquine-resistant malaria. 

• Forms basis of ACT (Artemisinin-based Combination Therapy), e.g., Artemether-Lumefantrine, Artesunate-Mefloquine. 

b. Derivatives: 

• Artemether, Artesunate, Dihydroartemisinin – improved solubility and bioavailability. 

• Used for severe and cerebral malaria. 

c. Anti-inflammatory & Antitumor Studies: 

• Shows promise in experimental models for anti-cancer and anti-inflammatory actions. 

d. Veterinary Use: 

• Used to treat protozoal infections in animals. 

 

Conclusion: 

Artemisinin is a life-saving compound in global malaria treatment. Its accurate estimation is vital for quality control of herbal formulations and therapeutic standardization, while its derivatives continue to play a central role in modern antimalarial therapy. 

24. Write the biological source, chemical constituents and uses of Benzoin or Belladonna. 

(Answering for Belladonna) 

 

1. Biological Source: 

• Belladonna consists of the dried leaves and flowering tops of Atropa belladonna Linn. 

• Family: Solanaceae 

• Common name: Deadly nightshade 

 

2. Chemical Constituents: 

a. Alkaloids (Primary Active Constituents): 

• Hyoscyamine (major component) 

• Atropine (racemic mixture) 

• Scopolamine (minor component) 

b. Other Constituents: 

• Flavonoids 

• Tannins 

• Coumarins 

• Small amount of volatile oil 

 

3. Uses: 

a. Anticholinergic Effects: 

• Atropine and hyoscyamine act as parasympatholytics, blocking muscarinic receptors. 

• Used to reduce salivation and bronchial secretions before surgery. 

b. Ophthalmic Use: 

• Atropine eye drops dilate the pupil (mydriasis) and paralyze the accommodation reflex (cycloplegia). 

c. Antispasmodic: 

• Used to relieve intestinal, ureteric, and biliary colic by relaxing smooth muscle. 

d. Antidote for Poisoning: 

• Antagonizes the effects of organophosphates and cholinergic drugs (e.g., pilocarpine, physostigmine). 

e. Parkinson’s Disease: 

• Helps manage tremors and rigidity due to anticholinergic activity. 

 

4. Precautions: 

• Toxic at higher doses – causes dry mouth, blurred vision, urinary retention, hallucinations. 

• Must be used under medical supervision. 

 

Conclusion: 

Belladonna is a classic medicinal plant valued for its potent tropane alkaloids. It plays a crucial role in ophthalmology, anesthesia, and emergency medicine due to its anticholinergic properties. 

25. Define tannins and write biological source and chemical constituents of drug used as expectorant. 

 

1. Definition of Tannins: 

Tannins are high molecular weight, polyphenolic compounds found in many plant species. They have the ability to precipitate proteins and alkaloids. Tannins are water-soluble and produce an astringent taste. 

 

Types of Tannins: 

• Hydrolysable Tannins – Yield gallic acid or ellagic acid upon hydrolysis (e.g., from Terminalia chebula) 

• Condensed Tannins – Also called proanthocyanidins; do not hydrolyze easily (e.g., from Cinchona). 

• Complex Tannins – A mix of hydrolysable and condensed types. 

 

2. Drug Used as Expectorant: 

Biological Source: 

• Glycyrrhiza glabra (Common name: Liquorice) 

• Family: Leguminosae 

 

3. Chemical Constituents of Liquorice: 

• Glycyrrhizin – A saponin glycoside (chief active constituent; up to 6–10%) 

• Liquiritin – A flavonoid glycoside 

• Glabridin – Isoflavonoid 

• Starch, sugars, and resin 

 

4. Medicinal Uses (as Expectorant): 

• Expectorant Action: 
  Glycyrrhizin stimulates secretion of mucus in the respiratory tract, facilitating removal of sputum. 

• Demulcent: 
  Soothes irritated mucous membranes in cough and sore throat. 

• Anti-inflammatory: 
  Useful in bronchitis and respiratory tract infections. 

• Corticosteroid-like effect: 
  Glycyrrhizin structurally mimics corticosteroids, reducing inflammation in the lungs and airways. 

 

Conclusion: 

Tannins have astringent and antioxidant properties, while Glycyrrhiza—rich in glycyrrhizin—is widely used as an expectorant. These natural compounds play an important role in managing respiratory ailments and supporting mucosal health. 

26. Write the application of spectroscopic methods used in identification of crude drugs. 

Spectroscopic methods are essential analytical tools in pharmacognosy and phytochemistry for the identification, characterization, and standardization of crude drugs and their phytoconstituents. 

 

1. UV-Visible Spectroscopy: 

• Principle: Measures absorption of ultraviolet or visible light by compounds with conjugated systems. 

• Application: 

• Identification of phenolic compounds, flavonoids, and alkaloids. 

• Used in quantitative analysis (e.g., artemisinin, curcumin). 

• Useful in detecting purity and presence of chromophores in plant extracts. 

 

2. Infrared (IR) Spectroscopy: 

• Principle: Based on absorption of IR radiation causing molecular vibrations. 

• Application: 

• Identification of functional groups (OH, C=O, NH₂) in phytoconstituents. 

• Confirm structure of compounds like menthol, alkaloids, terpenoids. 

 

3. Nuclear Magnetic Resonance (NMR) Spectroscopy: 

• Principle: Detects magnetic properties of certain atomic nuclei (¹H, ¹³C). 

• Application: 

• Structural elucidation of unknown phytoconstituents. 

• Differentiates between isomers and conformers. 

 

4. Mass Spectrometry (MS): 

• Principle: Ionizes chemical compounds and measures mass-to-charge ratio (m/z) of fragments. 

• Application: 

• Determination of molecular weight and molecular formula. 

• Used in fingerprinting complex plant mixtures. 

 

5. Combined Techniques: 

• GC-MS and LC-MS: 

• Identify volatile and non-volatile compounds respectively. 

• HPLC-UV: 

• Used in quality control and standardization of herbal formulations. 

 

Conclusion: 

Spectroscopic techniques provide accurate, reliable, and reproducible data for identifying crude drugs. These methods are indispensable for ensuring quality, efficacy, and safety in herbal medicine. 

27. Write biological source, active constituents and uses of Guggul or Aloes. 

(Answering for Guggul) 

 

1. Biological Source: 

• Guggul is the oleo-gum-resin obtained by making incisions in the bark of Commiphora wightii (syn. Commiphora mukul). 

• Family: Burseraceae 

 

2. Active Constituents: 

• Guggulsterones (E and Z isomers): 
  Main bioactive compounds with hypolipidemic properties. 

• Resins: 
  Contains myrrhanol, commiphoric acids. 

• Essential Oils: 
  Includes sesquiterpenes, e.g., α- and β-commiphorene. 

• Gum: 
  Contains arabinose, galactose, and glucuronic acid. 

 

3. Medicinal Uses: 

• Hypolipidemic Activity: 
  Guggulsterones reduce total cholesterol, triglycerides, and LDL levels. 

• Anti-inflammatory: 
  Used in treatment of arthritis, joint pain, and swelling. 

• Weight Management: 
  Helps in obesity management by enhancing thyroid function. 

• Cardioprotective: 
  Promotes healthy lipid profile and prevents atherosclerosis. 

• Antioxidant and Antimicrobial: 
  Beneficial in wound healing and skin disorders. 

 

4. Commercial Applications: 

• Used in Ayurvedic formulations like Triphala Guggulu and Yograj Guggulu. 

• Incorporated in nutraceuticals for heart and metabolic health. 

• Extracts standardized for guggulsterone content are sold as dietary supplements. 

 

Conclusion: 

Guggul is a pharmacologically significant oleo-gum-resin used for cardiovascular and metabolic health. Its active constituents, particularly guggulsterones, are widely studied and standardized in both herbal and modern medicine systems. 

28. Write a note on electrophoresis and its types. 

Electrophoresis is a separation technique based on the movement of charged particles under the influence of an electric field. It is widely used for the analysis and purification of biomolecules such as proteins, nucleic acids, and alkaloids. 

 

Principle: 

When an electric field is applied, charged molecules migrate towards the opposite electrode. The rate of migration depends on: 

• Charge 

• Molecular size 

• Shape 

• Medium used (e.g., gel, paper) 

 

Types of Electrophoresis: 

1. Paper Electrophoresis: 

• Medium: Whatman filter paper 

• Used for separation of small charged molecules like amino acids and alkaloids. 

• Visualization through ninhydrin spray or UV light. 

2. Gel Electrophoresis: 

• Uses agarose or polyacrylamide gels as supporting medium. 

• Suitable for DNA, RNA, and proteins. 

• Allows high resolution and precise separation. 

a. Agarose Gel Electrophoresis: 

• Mostly used for nucleic acids (DNA/RNA). 

• Separation based on size. 

b. SDS-PAGE (Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis): 

• Used for proteins. 

• SDS imparts uniform negative charge → proteins separated by molecular weight. 

3. Capillary Electrophoresis (CE): 

• Performed in narrow capillary tubes. 

• Offers high speed and resolution. 

• Used in pharmaceutical analysis and for small-volume samples. 

 

Applications: 

• Identification and purity analysis of plant alkaloids and enzymes 

• DNA fingerprinting 

• Protein separation and molecular weight determination 

• Quality control in herbal drug analysis 

 

Conclusion: 

Electrophoresis is a powerful analytical technique used in pharmacognosy and phytochemistry. Its various forms offer flexibility and precision in the separation and identification of complex plant-derived compounds. 

29. Give isolation and method of identification of terpenoids. 

Terpenoids, also called isoprenoids, are the largest class of plant secondary metabolites, formed from isoprene (C₅H₈) units. They include monoterpenes, sesquiterpenes, diterpenes, etc., and possess diverse biological activities such as antimicrobial, anti-inflammatory, and anticancer properties. 

 

1. Isolation of Terpenoids: 

a. Selection of Plant Source: 

• Common sources include Mentha, Cymbopogon, Zingiber, Boswellia, and Ginkgo. 

b. Extraction Methods: 

i. Steam Distillation: 

• Best suited for volatile terpenoids (e.g., menthol, limonene). 

• Plant material is distilled, and oil is collected by condensation. 

ii. Solvent Extraction: 

• Non-volatile terpenoids (e.g., taxol, boswellic acid) are extracted using solvents like hexane, ethanol, or chloroform. 

• Extract is concentrated using rotary evaporator. 

iii. Supercritical Fluid Extraction (SFE): 

• Uses CO₂ under pressure. 

• Environmentally friendly and highly selective method. 

 

2. Identification of Terpenoids: 

a. Thin Layer Chromatography (TLC): 

• Performed using silica gel plates. 

• Sprayed with vanillin-sulfuric acid reagent → produces colored spots indicating presence of terpenoids. 

b. High Performance Liquid Chromatography (HPLC): 

• Suitable for quantitative analysis of terpenoids like artemisinin and taxol. 

• C18 reverse-phase column with UV detection is commonly used. 

c. Gas Chromatography-Mass Spectrometry (GC-MS): 

• Ideal for volatile terpenoids. 

• Provides structural and molecular mass information. 

d. UV-Vis, IR, NMR Spectroscopy: 

• Used for structural elucidation: 

• IR identifies functional groups. 

• NMR provides detailed structural information. 

• UV confirms conjugated systems. 

 

Conclusion: 

Terpenoids are pharmaceutically significant compounds requiring precise isolation and identification techniques. Methods like steam distillation, TLC, HPLC, and GC-MS play critical roles in quality control and standardization of herbal products. 

30. Write a note on commercial applications of phenylpropanoids. 

Phenylpropanoids are a group of plant secondary metabolites derived from phenylalanine via the shikimic acid pathway. These compounds play key roles in plant defense and have important pharmaceutical, cosmetic, and food industry applications. 

 

1. Classification of Phenylpropanoids: 

• Simple phenylpropanoids: Cinnamic acid, coumaric acid 

• Coumarins: Umbelliferone, scopoletin 

• Flavonoids: Quercetin, kaempferol 

• Lignans and lignins: Podophyllotoxin 

• Stilbenes: Resveratrol 

 

2. Commercial Applications: 

a. Pharmaceutical Industry: 

• Antioxidant and anti-inflammatory agents: 
  Flavonoids like quercetin protect cells from oxidative damage. 

• Anticancer agents: 
  Podophyllotoxin, a lignan phenylpropanoid, is a precursor for etoposide and teniposide (used in cancer treatment). 

• Antimicrobial and antiviral effects: 
  Phenylpropanoids such as cinnamic acid derivatives exhibit antibacterial properties. 

b. Cosmetic Industry: 

• UV-protective agents: 
  Coumarins and flavonoids absorb UV radiation, making them useful in sunscreens. 

• Skin-lightening agents: 
  Phenylpropanoids like arbutin inhibit tyrosinase, reducing melanin synthesis. 

c. Food Industry: 

• Flavoring agents: 
  Cinnamic acid and its esters are used to flavor foods and beverages. 

• Preservatives: 
  Antioxidant phenylpropanoids extend the shelf life of food products. 

d. Agricultural Applications: 

• Used in biopesticides and plant growth regulators. 

• Help in allelopathy – suppressing the growth of neighboring weeds. 

 

3. Industrial Products: 

• Coumarins used in perfumes and as anticoagulants (e.g., warfarin synthesis). 

• Lignin derivatives used in adhesives and biodegradable plastics. 

 

Conclusion: 

Phenylpropanoids are multifunctional compounds with vast applications in health care, agriculture, and industry. Their natural origin and biological activities make them valuable ingredients in both traditional and modern formulations. 

31. Give estimation and utilization of sennosides. 

Sennosides are anthraquinone glycosides found in Senna leaves and pods, mainly from Cassia angustifolia and Cassia acutifolia (Family: Fabaceae). They are widely used as stimulant laxatives. 

 

1. Estimation of Sennosides: 

a. UV-Visible Spectrophotometry: 

• Principle: Measurement of absorbance after hydrolysis of sennosides to rhein anthrone. 

• Procedure: 

• Plant material is hydrolyzed with ferric chloride and HCl. 

• Extract is treated with sodium hydroxide to form a colored complex. 

• Absorbance is measured at 500–520 nm. 

• Advantages: Simple, reliable, and cost-effective for routine analysis. 

b. High Performance Liquid Chromatography (HPLC): 

• Column: C18 reverse-phase 

• Mobile phase: Methanol:Water or Acetonitrile:Phosphate buffer 

• Detection: UV at 265–270 nm 

• Accurately quantifies Sennoside A and B individually. 

c. Thin Layer Chromatography (TLC): 

• Used for qualitative identification. 

• Mobile phase: Ethyl acetate:methanol:water 

• Detected with UV or spraying reagents like KOH-methanol. 

 

2. Utilization of Sennosides: 

a. Laxative Use: 

• Sennosides stimulate peristalsis and increase bowel movement. 

• Used in chronic constipation and before diagnostic procedures like colonoscopy. 

b. Pharmaceutical Formulations: 

• Available in tablets, powders, syrups, and teas. 

• Often combined with bulk-forming laxatives (e.g., psyllium) or antispasmodics to reduce cramping. 

c. Pediatric and Geriatric Use: 

• Safe when used in recommended doses for children and the elderly under supervision. 

d. Herbal Products: 

• Commonly included in Ayurvedic, Unani, and homeopathic formulations for bowel regulation. 

 

Conclusion: 

Sennosides are clinically important phytoconstituents with well-established laxative action. Accurate estimation ensures quality control, while their utilization in various dosage forms makes them an essential component of modern and traditional medicine. 

32. Give application of spectroscopic techniques in phytochemical analysis. 

Spectroscopic techniques are vital in phytochemical analysis for the identification, characterization, and quantification of active constituents in crude drugs. They are non-destructive, sensitive, and provide detailed structural and functional group information. 

 

1. UV-Visible Spectroscopy: 

• Principle: Measures absorbance of ultraviolet or visible light by molecules with conjugated double bonds. 

• Applications: 

• Detection and quantification of flavonoids, phenolic compounds, and anthraquinones. 

• Used for estimating compounds like curcumin, sennosides, and artemisinin. 

• Monitoring chemical changes in extracts during storage or processing. 

 

2. Infrared (IR) Spectroscopy: 

• Principle: Identifies molecular vibrations (stretching, bending) corresponding to functional groups. 

• Applications: 

• Identifies OH, NH, CO, and C=C groups in phytoconstituents. 

• Confirms presence of terpenoids, glycosides, and alkaloids. 

• Differentiates between closely related herbal compounds. 

 

3. Nuclear Magnetic Resonance (NMR) Spectroscopy: 

• Principle: Explores magnetic properties of nuclei like ¹H and ¹³C. 

• Applications: 

• Detailed structure elucidation of complex phytoconstituents. 

• Identifies isomers and stereochemistry. 

• Used in characterization of compounds like glycyrrhizin, taxol, and reserpine. 

 

4. Mass Spectrometry (MS): 

• Principle: Detects ionized fragments of molecules and records mass-to-charge (m/z) ratios. 

• Applications: 

• Determines molecular weight and formula. 

• Structural characterization of unknown compounds. 

• Used in metabolomics and compound fingerprinting. 

 

5. Combined Techniques: 

• HPLC-UV / HPLC-MS: For precise quantification and identification of multiple phytochemicals in a mixture. 

• GC-MS: Best suited for volatile phytoconstituents like menthol, citral, and limonene. 

 

Conclusion: 

Spectroscopic techniques provide critical support in standardizing herbal medicines and identifying phytoconstituents with pharmacological relevance. Their application ensures consistency, efficacy, and safety of herbal drug formulations. 

33. Discuss modern techniques of extraction of crude drugs. 

Modern extraction techniques offer higher efficiency, selectivity, and eco-friendliness compared to traditional methods. They are designed to improve yield, purity, and speed in extracting active phytoconstituents from plant materials. 

 

1. Supercritical Fluid Extraction (SFE): 

• Principle: Uses supercritical CO₂ as the solvent under high pressure and temperature. 

• Advantages: 

• Selective for non-polar to moderately polar compounds (e.g., terpenoids). 

• No solvent residue, environment-friendly. 

• Applications: Extraction of essential oils, flavonoids, and lipophilic constituents like guggulsterones. 

 

2. Microwave-Assisted Extraction (MAE): 

• Principle: Uses microwaves to rapidly heat the solvent and plant matrix, enhancing extraction. 

• Advantages: 

• Short extraction time, high yield. 

• Reduced solvent consumption. 

• Applications: Extraction of alkaloids, glycosides, polyphenols, and saponins. 

 

3. Ultrasound-Assisted Extraction (UAE): 

• Principle: Ultrasonic waves create cavitation, disrupting cell walls and enhancing solvent penetration. 

• Advantages: 

• Energy efficient, effective for thermolabile compounds. 

• Applications: Used for extracting flavonoids, tannins, and phenolics. 

 

4. Accelerated Solvent Extraction (ASE): 

• Also known as Pressurized Liquid Extraction (PLE). 

• Uses high temperature and pressure to improve solvent efficiency. 

• Suitable for rapid extraction of heat-stable compounds. 

 

5. Enzyme-Assisted Extraction (EAE): 

• Uses enzymes like cellulase, pectinase to break down plant cell walls. 

• Enhances release of bioactive compounds. 

• Often combined with MAE or UAE. 

 

6. Soxhlet Extraction (Improved Automated Versions): 

• Though traditional, automated Soxhlet systems have been modernized for solvent recycling and controlled heating. 

 

Conclusion: 

Modern extraction techniques maximize yield, maintain bioactivity, and ensure cleaner extracts. These advancements support large-scale production and quality assurance in herbal pharmaceutical industries. 

34. Write a note on utilization of radioactive isotopes in investigating biogenetic pathways. 

Radioactive isotopes are valuable tools in studying biogenetic pathways—the sequences of chemical reactions through which plants synthesize secondary metabolites such as alkaloids, glycosides, flavonoids, and terpenoids. 

 

1. Principle: 

A radioactive isotope (e.g., ¹⁴C, ³H, ³²P) is introduced into a precursor molecule. As the plant metabolizes it, the radioactive label gets incorporated into newly formed compounds. By tracing the movement and location of the radioactivity, scientists determine: 

• The sequence of biochemical steps 

• The intermediates involved 

• The origin of carbon atoms in final products 

 

2. Commonly Used Radioactive Isotopes: 

• Carbon-14 (¹⁴C): Widely used in labeling carbon atoms of glucose, shikimic acid, or phenylalanine. 

• Tritium (³H): For labeling hydrogen atoms. 

• Phosphorus-32 (³²P): For studying phosphate metabolism in nucleotide biosynthesis. 

 

3. Applications in Biogenetic Studies: 

a. Pathway Elucidation: 

• Tracing ¹⁴C-labeled acetate into terpenoids confirms their biosynthesis via the mevalonate pathway. 

• Labeling phenylalanine with ¹⁴C reveals its conversion into flavonoids and coumarins via the shikimic acid pathway. 

b. Identification of Precursors and Intermediates: 

• Used to identify unknown steps or intermediates in alkaloid biosynthesis, e.g., in morphine and reserpine. 

c. Kinetic Studies: 

• To measure rate of biosynthesis, turnover, and accumulation of metabolites. 

d. Gene Function Studies: 

• Helps in confirming the enzymes responsible for each step when paired with gene knockout studies. 

 

4. Advantages: 

• Highly sensitive and specific 

• Requires small amounts of isotope 

• Helps in understanding complex biochemical routes not possible by conventional methods 

 

Conclusion: 

Radioactive isotopes have revolutionized the understanding of plant biosynthetic processes. They provide precise and dynamic information on how phytoconstituents are synthesized, making them indispensable in pharmacognosy and phytochemistry research. 

35. Give bioresources, therapeutic and commercial applications of any two resin-containing drugs. 

*(Answering for: Colophony and Benzoin) 

 

1. Colophony (Rosin): 

a. Bioresource: 

• Obtained from the oleoresin of Pinus species, especially Pinus palustris and Pinus longifolia (Family: Pinaceae). 

• It is a solid residue after distilling turpentine oil. 

b. Therapeutic Applications: 

• Topical protectant and emollient in ointments and plasters. 

• Has mild antimicrobial and analgesic properties when used in medicated dressings. 

c. Commercial Applications: 

• Used in manufacturing adhesives, varnishes, printing inks, and soap. 

• Used as a base for dental cements and sealing wax. 

• Acts as a stiffening agent in pharmaceutical plasters and bandages. 

 

2. Benzoin: 

a. Bioresource: 

• Balsamic resin obtained from Styrax benzoin and Styrax tonkinensis (Family: Styracaceae). 

• Collected by incising the trunk. 

b. Therapeutic Applications: 

• Used in inhalants for treating respiratory infections due to its expectorant and antiseptic properties. 

• Component of compound tincture of benzoin, used topically for skin protection and wound healing. 

• Acts as a fixative in perfumes. 

c. Commercial Applications: 

• Extensively used in cosmetics, incense, and fragrance industries. 

• Used in pharmaceutical formulations as a preservative and flavoring agent. 

• Forms a component in adhesive sprays used in medical and athletic settings. 

 

Conclusion: 

Colophony and benzoin are important resin-containing drugs with wide-ranging pharmaceutical and industrial uses. Their applications span across medicine, cosmetics, and chemical industries, highlighting the commercial importance of natural resins. 

36. Give method of isolation, identification and analysis of rutin. 

Rutin is a flavonoid glycoside consisting of quercetin and the disaccharide rutinose. It is known for its antioxidant, capillary-strengthening, and anti-inflammatory properties. 

 

1. Source of Rutin: 

• Found in Ruta graveolens (Rue), Fagopyrum esculentum (Buckwheat), Eucalyptus, and Tobacco leaves. 

 

2. Method of Isolation: 

a. Plant Extraction: 

• Dried plant material is powdered and subjected to cold or hot solvent extraction using methanol, ethanol, or aqueous ethanol. 

b. Filtration & Concentration: 

• The extract is filtered and concentrated under reduced pressure. 

c. Purification: 

• Crude extract may be further purified using column chromatography on silica gel. 

• Elution is done using methanol or ethyl acetate to separate rutin. 

 

3. Identification of Rutin: 

a. Thin Layer Chromatography (TLC): 

• Mobile Phase: Ethyl acetate:formic acid:acetic acid:water (100:11:11:27) 

• Spray Reagent: Aluminum chloride (AlCl₃) under UV light shows yellow fluorescence. 

b. Chemical Tests: 

• Rutin gives positive Shinoda test for flavonoids. 

• Mix with magnesium turnings + HCl → pink/red coloration due to flavonoid core. 

c. UV-Vis Spectroscopy: 

• Exhibits absorbance maxima around 256 nm and 355 nm characteristic of flavonol glycosides. 

 

4. Quantitative Analysis: 

a. High Performance Liquid Chromatography (HPLC): 

• Column: C18 reverse-phase 

• Mobile Phase: Methanol:Water or Acetonitrile:Phosphate buffer 

• Detection: UV at 254–360 nm 

• Accurately quantifies rutin in plant extracts and formulations. 

b. Spectrophotometry: 

• Based on the formation of flavonoid-aluminum complex and measurement at 415 nm. 

 

Conclusion: 

Rutin is a bioactive flavonoid with therapeutic benefits. Its isolation and identification involve solvent extraction and chromatographic techniques, while HPLC and UV spectrophotometry are preferred methods for quantitative analysis in herbal quality control. 

37. Write isolation method of reserpine and its chemical tests for identification. 

Reserpine is an indole alkaloid mainly used as an antihypertensive and tranquilizer, obtained from Rauwolfia serpentina (Family: Apocynaceae). 

 

1. Isolation Method of Reserpine: 

a. Plant Material: 

• Dried and powdered roots of Rauwolfia serpentina are used. 

b. Defatting: 

• Powdered root is treated with petroleum ether to remove fats and chlorophyll. 

c. Extraction: 

• Defatted powder is extracted with acidified alcohol (ethanol containing dilute HCl) using percolation or Soxhlet method. 

d. Filtration and Concentration: 

• The alcoholic extract is filtered and concentrated under reduced pressure to get a crude alkaloidal extract. 

e. Basification: 

• The extract is made alkaline using ammonia solution to liberate free alkaloids. 

f. Solvent Extraction: 

• Alkaloids are extracted with chloroform or benzene. 

g. Purification: 

• The chloroform extract is evaporated and reserpine is purified using column chromatography with silica gel, using chloroform:methanol as eluent. 

 

2. Chemical Tests for Identification of Reserpine: 

a. Van Urk’s Test (Specific for Indole Alkaloids): 

• Reserpine + p-dimethylaminobenzaldehyde + HCl → purple or violet color. 

b. Liebermann-Burchard Test: 

• Reserpine + acetic anhydride + sulfuric acid → green to blue color indicates the presence of ester group in reserpine. 

c. TLC Identification: 

• Mobile Phase: Chloroform:methanol (9:1) 

• Detection: UV light at 254 nm; reserpine appears as a dark spot. 

d. UV Spectroscopy: 

• Exhibits characteristic absorbance maxima near 268 nm and 320 nm. 

 

Conclusion: 

Reserpine is isolated from Rauwolfia roots by solvent extraction and column purification. It is identified by specific color reactions, TLC, and UV spectroscopy, and is widely used for its antihypertensive and sedative effects in medicine. 

38. Discuss in detail about Glycyrrhetinic acid. 

Glycyrrhetinic acid is a bioactive triterpenoid compound derived from glycyrrhizin, the major sweet-tasting saponin glycoside found in the roots of Glycyrrhiza glabra (liquorice). It is known for its anti-inflammatory, anti-ulcer, and antiviral properties. 

 

1. Source: 

• Botanical name: Glycyrrhiza glabra 

• Family: Leguminosae 

• Glycyrrhetinic acid is obtained by hydrolysis of glycyrrhizin. 

 

2. Chemical Nature: 

• A pentacyclic triterpenoid aglycone. 

• Glycyrrhizin = Glycyrrhetinic acid (aglycone) + glucuronic acid (sugar moiety). 

 

3. Methods of Isolation: 

a. Hydrolysis of Glycyrrhizin: 

• Acidic or enzymatic hydrolysis of glycyrrhizin releases glycyrrhetinic acid. 

• Solvent extraction (e.g., with ether or ethyl acetate) is then used to isolate the aglycone. 

b. Purification: 

• Crude product is purified using column chromatography or recrystallization. 

 

4. Pharmacological Activities: 

a. Anti-inflammatory: 

• Inhibits prostaglandin metabolism and hydrocortisone degradation. 

• Used in treating eczema, dermatitis, and ulcers. 

b. Antiviral: 

• Inhibits viral replication (e.g., herpes simplex, hepatitis B and C). 

c. Anti-ulcer: 

• Promotes mucus secretion in the stomach, aiding in peptic ulcer treatment. 

d. Corticosteroid-like effect: 

• Mimics the activity of corticosteroids by inhibiting 11β-hydroxysteroid dehydrogenase, increasing cortisol levels locally. 

 

5. Applications: 

• Used in topical creams for skin conditions. 

• Found in oral preparations for cough, sore throat, and gastric ulcers. 

• Incorporated into cosmetics and health supplements. 

 

6. Adverse Effects (if overused): 

• Pseudohyperaldosteronism: Sodium retention, potassium loss, hypertension, and edema. 

 

Conclusion: 

Glycyrrhetinic acid is a therapeutically important compound derived from liquorice, with a broad range of pharmacological and commercial applications. It exemplifies how plant-based compounds can mimic and enhance physiological effects relevant to modern medicine. 

39. Write a short note on UV. 

Ultraviolet (UV) spectroscopy is a widely used analytical technique in phytochemistry and pharmacognosy for the qualitative and quantitative analysis of compounds that absorb UV or visible light. 

 

1. Principle: 

• UV spectroscopy is based on the absorption of ultraviolet radiation (200–400 nm) by molecules with conjugated π-electrons or *non-bonding electrons (n→π)**. 

• When a molecule absorbs UV radiation, electrons are excited from ground to higher energy levels. 

 

2. Types of Transitions: 

• π → π*: Found in compounds with double bonds (e.g., flavonoids, phenols). 

• n → π*: Seen in compounds with lone pair electrons like carbonyls, aldehydes, etc. 

 

3. Applications in Phytochemistry: 

a. Identification of Phytoconstituents: 

• UV spectra help in identifying flavonoids, phenolics, alkaloids, and coumarins. 

• Distinct absorption maxima (λmax) serve as fingerprints for specific compounds. 

b. Estimation (Quantitative Analysis): 

• UV spectrophotometry is used to estimate compounds such as: 

• Curcumin (λmax ~ 425 nm) 

• Sennosides (λmax ~ 500–520 nm after derivatization) 

• Rutin and quercetin (λmax ~ 256–370 nm) 

c. Detection of Impurities: 

• Useful in quality control to detect degradation products or contaminants in herbal extracts. 

 

4. Instrumentation Components: 

• Light source: Deuterium or tungsten lamp. 

• Monochromator: Separates light into different wavelengths. 

• Sample holder: Quartz cuvette (transparent to UV). 

• Detector: Converts absorbed light into an electrical signal for display. 

 

5. Advantages: 

• Non-destructive, rapid, and sensitive. 

• Requires small sample quantity. 

• Useful for both routine analysis and research. 

40. Production of Taxol. 

Taxol, also known as Paclitaxel, is a complex diterpenoid alkaloid with potent anticancer properties. It is primarily used in the treatment of ovarian, breast, and lung cancers. Originally isolated from the bark of the Pacific yew tree (Taxus brevifolia, Family: Taxaceae), its production now includes several biotechnological and semi-synthetic methods due to low natural yield. 

 

1. Natural Source: 

• Botanical name: Taxus brevifolia (Pacific yew tree) 

• Part used: Bark 

• Contains very low content of taxol (~0.01% of dry weight), making extraction unsustainable. 

 

2. Production Methods: 

a. Extraction from Natural Source: 

• Bark is powdered and extracted with organic solvents like methanol or dichloromethane. 

• Extract is concentrated and purified using chromatography (column or HPLC). 

Limitations: 

• Ecological damage due to bark harvesting. 

• Low yield and high cost. 

 

b. Semi-Synthetic Production: 

• Uses 10-Deacetylbaccatin III from Taxus baccata leaves as a precursor. 

• Chemically modified into taxol using side chain attachment in lab conditions. 

• More sustainable and widely used commercially. 

 

c. Plant Cell Culture Technique: 

• In vitro cultivation of Taxus species cells in bioreactors. 

• Cells produce taxol under optimized conditions (light, elicitors, hormones). 

• Enhances yield without harming the plant. 

Advantages: 

• Eco-friendly 

• Controlled environment 

• Scalable 

 

d. Genetic Engineering and Microbial Production (Future Scope): 

• Introduction of taxol biosynthetic genes into endophytic fungi or microbes like E. coli or Saccharomyces. 

• Still under research, but promising for large-scale production. 

 

3. Commercial Importance: 

• Marketed under the brand name Taxol® by Bristol-Myers Squibb. 

• Included in the WHO Model List of Essential Medicines. 

• Used in chemotherapy protocols worldwide. 

 

Conclusion: 

Taxol is a life-saving anticancer drug with complex production processes. Due to sustainability concerns, semi-synthetic and biotechnological approaches have replaced traditional extraction. Its successful commercialization demonstrates the value of natural products in modern medicine. 

41. Discuss isolation and identification of Curcumin. 

Curcumin is a yellow-colored polyphenolic compound obtained from Curcuma longa (Turmeric). It exhibits anti-inflammatory, antioxidant, anticancer, and hepatoprotective properties and is widely used in both traditional and modern medicine. 

 

1. Source: 

• Botanical name: Curcuma longa 

• Family: Zingiberaceae 

• Part used: Rhizome 

 

2. Isolation of Curcumin: 

a. Extraction: 

• Solvent used: Ethanol, acetone, or methanol. 

• Procedure: 

• Dried turmeric rhizomes are powdered. 

• Powder is extracted using hot ethanol by maceration or Soxhlet extraction. 

• The extract is filtered and concentrated under reduced pressure. 

b. Purification: 

• Concentrated extract is treated with hexane to remove oil and then recrystallized using ethanol or acetone to isolate crude curcumin. 

c. Column Chromatography: 

• Further purification is done using silica gel column chromatography. 

• Eluted with chloroform:methanol (9:1) to obtain pure curcumin. 

 

3. Identification of Curcumin: 

a. Thin Layer Chromatography (TLC): 

• Stationary phase: Silica gel 

• Mobile phase: Chloroform:methanol 

• Detection: Yellow-orange spot at Rf ~ 0.6 under UV light or iodine vapors. 

b. UV-Visible Spectroscopy: 

• λmax: 420–430 nm 

• Absorption indicates presence of conjugated dienes and keto groups. 

c. Infrared Spectroscopy (IR): 

• Characteristic peaks for OH, C=O, and aromatic C=C. 

• Confirms functional groups in curcumin. 

d. HPLC (High Performance Liquid Chromatography): 

• Column: C18 

• Mobile phase: Methanol:water or acetonitrile:buffer 

• Used for quantification and purity analysis. 

e. Color Test: 

• With alkaline solution, curcumin gives a reddish-brown color due to phenolic groups. 

 

Conclusion: 

Curcumin is isolated from turmeric using solvent extraction and chromatography, and identified by spectral techniques and TLC. It is a prominent natural product used in nutraceuticals and pharmaceuticals for its broad therapeutic activities. 

42. Give identification tests for quinine and caffeine. 

Quinine and Caffeine are alkaloids with distinct chemical structures and physiological effects. Both can be identified through specific chemical and instrumental tests. 

 

1. Identification Tests for Quinine: 

a. Thalleioquin Test (Specific Test): 

• Procedure: Add bromine water and ammonia to a solution of quinine. 

• Observation: A green color appears, indicating presence of quinine. 

b. Fluorescence Test: 

• Procedure: Dissolve quinine sulfate in dilute sulfuric acid. 

• Observation: Shows blue fluorescence under UV light (due to methoxyquinoline structure). 

c. UV Spectroscopy: 

• Quinine shows characteristic absorption around 330–350 nm. 

d. TLC: 

• Rf value: Specific for quinine in a suitable solvent system (e.g., chloroform:methanol). 

• Detected using UV light (254 nm) or iodine vapors. 

 

2. Identification Tests for Caffeine: 

a. Murexide Test (Specific Test): 

• Procedure: 

• Evaporate caffeine with a drop of nitric acid to dryness. 

• Expose residue to ammonia vapors. 

• Observation: A purple or violet color appears, indicating caffeine. 

b. Tannic Acid Test: 

• Procedure: Add tannic acid to an aqueous solution of caffeine. 

• Observation: Formation of a precipitate indicates xanthine alkaloids. 

c. UV Spectroscopy: 

• Caffeine absorbs UV light strongly at 271 nm, confirming its presence. 

d. TLC: 

• Caffeine can be identified on TLC plate using chloroform:methanol (9:1) as mobile phase. 

• Spots are visible under UV light. 

 

Conclusion: 

Both quinine and caffeine can be reliably identified using simple color reactions, UV fluorescence, and chromatographic as well as spectrophotometric techniques. These tests are crucial for quality control and authentication of crude drug samples. 

43. Rauwolfia 

Rauwolfia is one of the most important medicinal plants used in both modern and traditional medicine, primarily for its antihypertensive and sedative properties. The main active constituents are indole alkaloids, especially reserpine. 

 

1. Biological Source: 

• Botanical name: Rauwolfia serpentina 

• Family: Apocynaceae 

• Part used: Dried roots 

 

2. Geographical Distribution: 

• Native to India, Sri Lanka, Bangladesh, and parts of Southeast Asia. 

• Widely cultivated in tropical regions for medicinal use. 

 

3. Chemical Constituents: 

• The plant contains over 50 alkaloids, the most significant being: 

• Reserpine – hypotensive and tranquilizing activity 

• Ajmaline – antiarrhythmic effect 

• Serpentine, Rescinnamine, Yohimbine 

• Most alkaloids belong to the indole and ajmaline types. 

 

4. Pharmacological Actions: 

• Antihypertensive: Reserpine depletes catecholamines (e.g., norepinephrine), lowering blood pressure. 

• Tranquilizing/Sedative: Used in mild psychotic disorders. 

• Antiarrhythmic: Ajmaline is used for treating cardiac arrhythmias. 

• Antipsychotic: Previously used in schizophrenia (limited due to side effects). 

 

5. Medicinal Uses: 

• Treatment of hypertension, insomnia, anxiety, and mental agitation. 

• Used in Ayurveda for snake bites, fevers, and bowel disorders. 

 

6. Side Effects: 

• Depression, nasal congestion, bradycardia, and gastrointestinal issues with prolonged reserpine use. 

• Must be administered under medical supervision. 

 

7. Commercial Preparations: 

• Tablets, capsules, and herbal formulations (e.g., Serpina by Himalaya). 

• Also used as a source of semi-synthetic alkaloids. 

 

Conclusion: 

Rauwolfia serpentina remains a cornerstone of herbal cardiovascular medicine, especially for its reserpine content. Due to its potent pharmacological actions, it has contributed significantly to both modern drug development and traditional medicine systems. 

44. Give identification tests for alkaloids. 

Alkaloids are basic nitrogen-containing natural compounds, commonly found in medicinal plants, and often exhibit pharmacological activity. They are typically identified using color reactions and precipitating reagents due to their basic and heterocyclic nature. 

 

1. General Identification Tests (Precipitation Tests): 

These tests are based on the reaction of alkaloids with alkaloidal reagents, forming insoluble precipitates. 

a. Dragendorff’s Test: 

• Reagent: Bismuth nitrate + potassium iodide 

• Result: Formation of orange or reddish-brown precipitate 

• Interpretation: Indicates presence of alkaloids 

b. Mayer’s Test: 

• Reagent: Potassium mercuric iodide 

• Result: Cream-colored precipitate 

• Use: Widely used as a screening test for alkaloids 

c. Wagner’s Test: 

• Reagent: Iodine in potassium iodide 

• Result: Reddish-brown precipitate 

d. Hager’s Test: 

• Reagent: Saturated picric acid solution 

• Result: Yellow precipitate 

 

2. Specific Color Reactions: 

These tests help in identifying specific types of alkaloids. 

a. Vitali-Morin Test (for Tropane Alkaloids like Atropine): 

• Procedure: Alkaloid is treated with fuming nitric acid and evaporated to dryness, then treated with alcoholic potassium hydroxide. 

• Observation: Violet color appears. 

b. Murexide Test (for Purine Alkaloids like Caffeine and Theobromine): 

• Procedure: Add nitric acid and evaporate; expose to ammonia vapors. 

• Observation: Purple color indicates xanthine alkaloids. 

c. Marquis Test (for Morphine): 

• Reagent: Formaldehyde + sulfuric acid 

• Result: Formation of purple color indicates morphine. 

 

3. Thin Layer Chromatography (TLC): 

• Alkaloids can also be separated and detected using TLC on silica gel plates. 

• Spray reagents: Dragendorff’s or iodine vapors. 

• Alkaloids appear as distinct colored spots under UV light or after spraying. 

 

Conclusion: 

Alkaloids are identified through a range of general precipitation tests, specific color reactions, and TLC methods. These tests help confirm the presence and type of alkaloids in plant extracts and are essential in quality control and phytochemical screening. 

45. Shikimic acid pathway. 

The Shikimic acid pathway is a crucial biosynthetic route in plants and microorganisms responsible for the production of aromatic compounds, including many important secondary metabolites such as alkaloids, flavonoids, tannins, and lignin precursors. 

 

1. Location: 

• Occurs in the plastids (chloroplasts) of plant cells. 

• Absent in animals, which is why the pathway is a target for herbicides and antibiotics. 

 

2. Starting Materials: 

• Phosphoenolpyruvate (PEP) from glycolysis 

• Erythrose-4-phosphate from the pentose phosphate pathway 

 

3. Key Steps in the Pathway: 

1. Condensation of PEP and Erythrose-4-phosphate to form 3-deoxy-D-arabino-heptulosonic acid-7-phosphate (DAHP). 

2. DAHP undergoes multiple enzymatic reactions to form shikimic acid. 

3. Shikimic acid is phosphorylated to shikimate-3-phosphate, which reacts with PEP again to form 5-enolpyruvyl shikimate-3-phosphate (EPSP). 

4. EPSP is converted to chorismic acid, a central branching point. 

 

4. End Products of Shikimic Pathway: 

• Aromatic amino acids: 

• Phenylalanine 

• Tyrosine 

• Tryptophan 

• These amino acids serve as precursors for: 

• Flavonoids (via phenylalanine) 

• Coumarins 

• Lignins 

• Alkaloids (especially indole-type via tryptophan) 

• Tannins 

• Phenolic acids 

 

5. Pharmaceutical Relevance: 

• Shikimic acid is used industrially to synthesize oseltamivir (Tamiflu), an antiviral drug. 

• Targeted by herbicides like glyphosate, which inhibits EPSP synthase. 

 

6. Importance in Phytochemistry: 

• Explains the biosynthetic origin of many phenolic and alkaloidal compounds found in medicinal plants. 

• Assists in designing biotechnological approaches for enhanced production of valuable metabolites. 

 

Conclusion: 

The Shikimic acid pathway is fundamental for the synthesis of aromatic secondary metabolites in plants. Understanding this pathway aids in metabolic engineering, drug discovery, and the standardization of herbal medicines. 

46. Give the biological source, chemical constituents, uses and commercial application of Rauwolfia. 

 

1. Biological Source: 

• Botanical name: Rauwolfia serpentina 

• Family: Apocynaceae 

• Part used: Dried roots 

• Commonly known as Sarpagandha. 

 

2. Chemical Constituents: 

Rauwolfia contains over 50 indole alkaloids, with the following being most important: 

• Reserpine – major hypotensive and tranquilizing alkaloid 

• Ajmaline – antiarrhythmic agent 

• Serpentine, Rescinnamine, Yohimbine – with additional CNS and cardiovascular effects 

• Minor amounts of ajmalicine and alstonine 

These alkaloids are primarily responsible for the drug’s pharmacological activity. 

 

3. Medicinal Uses: 

a. Antihypertensive: 

• Reserpine lowers blood pressure by depleting norepinephrine from sympathetic nerve endings. 

b. CNS Depressant: 

• Used as a tranquilizer in mild psychotic disorders and insomnia. 

c. Antiarrhythmic: 

• Ajmaline regulates irregular heartbeat in cardiovascular conditions. 

d. Traditional Uses: 

• Used in Ayurveda and Unani medicine for snake bites, mental agitation, fever, and bowel disorders. 

 

4. Commercial Applications: 

a. Pharmaceutical Industry: 

• Reserpine is used in combination with other drugs for hypertension therapy. 

• Rauwolfia root extract is formulated into tablets, capsules, and tinctures. 

b. Herbal Formulations: 

• Present in marketed Ayurvedic products like Sarpagandha Vati and Serpina (by Himalaya). 

c. Research and Drug Development: 

• Used as a prototype for the development of new antihypertensive and neuroactive drugs. 

 

5. Caution: 

• Prolonged use may lead to depression, nasal congestion, and bradycardia. 

• Contraindicated in patients with gastric ulcers and mental depression. 

 

Conclusion: 

Rauwolfia serpentina is a pharmacologically potent plant with well-defined applications in modern and traditional medicine. Its rich content of indole alkaloids, especially reserpine, makes it a valuable herb in the treatment of cardiovascular and mental disorders. 

47. Write down the method of isolation, identification and analysis of Menthol. 

Menthol is a cyclic monoterpenoid alcohol obtained from the volatile oil of Mentha species. It has distinct cooling, analgesic, antipruritic, and flavoring properties and is widely used in pharmaceuticals and personal care products. 

 

1. Source: 

• Botanical name: Mentha arvensis, Mentha piperita 

• Family: Lamiaceae 

• Part used: Aerial parts (leaves and stems) 

• Menthol is the major constituent of peppermint oil. 

 

2. Isolation Method: 

a. Steam Distillation: 

• Fresh or dried Mentha leaves are subjected to steam distillation. 

• The volatile oil collected is cooled, and crude menthol crystallizes out due to its low solubility at room temperature. 

b. Separation and Purification: 

• Crystals are separated by filtration and recrystallized from alcohol or acetone to obtain pure menthol. 

• The remaining oil (menthol-free) is used for flavoring. 

 

3. Identification Tests: 

a. Physical Characteristics: 

• Appearance: Colorless, crystalline solid with a strong peppermint odor. 

• Melting point: 41–44°C 

b. Solubility Test: 

• Soluble in alcohol and chloroform, slightly soluble in water. 

c. Color Reaction: 

• Menthol + sulfuric acid → red coloration (due to dehydration and polymerization). 

d. IR Spectroscopy: 

• Shows characteristic peaks at: 

• ~3300 cm⁻¹ (–OH group) 

• ~2950 cm⁻¹ (C–H stretching of alkane) 

• ~1050 cm⁻¹ (C–O stretching) 

 

4. Analysis: 

a. Gas Chromatography (GC): 

• Menthol is quantified using GC with flame ionization detector. 

• Retention time confirms identity; peak area gives concentration. 

b. Thin Layer Chromatography (TLC): 

• Mobile phase: Hexane:ethyl acetate (8:2) 

• Menthol appears as a distinct spot under UV light or iodine staining. 

c. UV Spectroscopy: 

• Menthol does not strongly absorb in UV; minimal use here. 

 

Conclusion: 

Menthol is isolated through steam distillation and crystallization, and identified by its physical properties, IR spectra, and chromatographic behavior. It is extensively used in cosmetics, oral care, topical analgesics, and flavor industries. 

48. Write a note on Amino acid pathway. 

The Amino Acid Pathway is a major biosynthetic route in plants that leads to the formation of various secondary metabolites such as alkaloids, flavonoids, glucosinolates, and phenolic compounds. This pathway utilizes essential amino acids as precursors. 

 

1. Importance of the Amino Acid Pathway: 

• Provides building blocks for bioactive phytochemicals. 

• Supports the biosynthesis of nitrogen-containing compounds. 

• Crucial for the production of plant defense molecules and medicinal alkaloids. 

 

2. Key Amino Acids and Their Derived Products: 

a. Phenylalanine: 

• Precursor for phenylpropanoids, flavonoids, coumarins, and tannins. 

• First step is conversion to cinnamic acid via phenylalanine ammonia-lyase (PAL). 

b. Tyrosine: 

• Leads to isoquinoline alkaloids, dopamine, and lignins. 

• Also participates in the synthesis of pigments and hormones. 

c. Tryptophan: 

• Produces indole alkaloids like reserpine, strychnine, serotonin, and indole-3-acetic acid (IAA). 

d. Ornithine and Lysine: 

• Give rise to tropane alkaloids such as atropine, hyoscyamine, and cocaine. 

e. Histidine: 

• Serves as a precursor for histamine and some imidazole alkaloids. 

 

3. Examples of Secondary Metabolites Derived: 

Amino Acid	Derived Metabolites	Example Plants
Phenylalanine	Flavonoids, tannins	Tea, Citrus
Tyrosine	Morphine, dopamine	Papaver, Mucuna
Tryptophan	Reserpine, vincristine	Rauwolfia, Catharanthus
Lysine	Piperidine alkaloids	Lobelia
Ornithine	Atropine, scopolamine	Atropa, Datura

 

4. Pharmaceutical Importance: 

• These metabolites show various biological activities: 

• CNS depressant (reserpine) 

• Anti-cancer (vincristine) 

• Cardiovascular agents (ajmaline) 

• Analgesics (morphine) 

 

Conclusion: 

The amino acid pathway is central to the biosynthesis of alkaloids and other nitrogenous secondary metabolites. It illustrates the metabolic versatility of plants in producing pharmacologically active compounds, many of which are utilized in modern medicine. 

49. Write a note on: 

  i) Liquorice 
  ii) Vincristine** 

 

i) Liquorice: 

1. Biological Source: 

• Glycyrrhiza glabra 

• Family: Leguminosae 

• Part used: Dried peeled/unpeeled roots and stolons 

2. Chemical Constituents: 

• Glycyrrhizin (triterpenoid saponin glycoside) 

• Glycyrrhetinic acid (aglycone form) 

• Flavonoids like liquiritin, isoliquiritin 

• Polysaccharides, starch, and resins 

3. Uses: 

• Expectorant: Used in cough syrups 

• Anti-ulcer: Protects gastric mucosa 

• Anti-inflammatory: Topical and internal uses 

• Sweetening agent: 50 times sweeter than sugar 

• Used in formulations for bronchitis, sore throat, and peptic ulcers 

4. Commercial Application: 

• Widely used in pharmaceuticals, cosmetics, and confectionery. 

• Included in formulations like “Glycyrrhiza compound” and herbal lozenges. 

 

ii) Vincristine: 

1. Biological Source: 

• Isolated from Catharanthus roseus (also known as Vinca rosea) 

• Family: Apocynaceae 

• Part used: Whole plant 

2. Chemical Constituents: 

• Vincristine and Vinblastine: Indole alkaloids 

• Other alkaloids: Ajmalicine, serpentine, lochnerine 

3. Mechanism of Action: 

• Binds to tubulin, inhibiting microtubule formation 

• Arrests cell division in metaphase 

• Effective in rapidly dividing cancer cells 

4. Uses: 

• Anticancer drug used in the treatment of: 

• Acute lymphocytic leukemia (ALL) 

• Hodgkin’s lymphoma 

• Neuroblastoma and Wilms' tumor 

5. Commercial Application: 

• Marketed as Oncovin® (Vincristine sulfate) 

• Used alone or in combination chemotherapy regimens 

• Requires careful dosing due to neurotoxicity 

 

Conclusion: 

Both liquorice and vincristine are important plant-derived drugs. Liquorice is valued for its soothing and anti-inflammatory effects, while vincristine is a potent anticancer agent, highlighting the therapeutic potential of natural products in modern medicine. 

50. Give the therapeutic uses and commercial application of Caffeine and Asafoetida. 

 

i) Caffeine 

1. Source: 

• Obtained from seeds and leaves of Coffea arabica, Camellia sinensis, and Theobroma cacao 

• Belongs to the class of purine alkaloids (xanthines) 

2. Chemical Nature: 

• Trimethylxanthine alkaloid 

• CNS stimulant and adenosine receptor antagonist 

3. Therapeutic Uses: 

• Central Nervous System Stimulant: Increases alertness and decreases fatigue 

• Respiratory Stimulant: Used in neonatal apnea 

• Analgesic Adjuvant: Enhances the action of pain relievers like aspirin and acetaminophen 

• Diuretic: Promotes urine formation 

• Migraine Treatment: Used in combination with ergotamine or paracetamol 

4. Commercial Application: 

• Found in coffee, tea, cola drinks, and energy beverages 

• Incorporated in pharmaceutical preparations like Anacin, Excedrin 

• Used in cosmetic products to reduce puffiness and stimulate circulation 

 

ii) Asafoetida 

1. Source: 

• Oleo-gum-resin obtained from the rhizome and root of Ferula asafoetida 

• Family: Umbelliferae (Apiaceae) 

2. Chemical Nature: 

• Contains resins (ferulic acid derivatives), volatile oils (sulphur compounds), and gum 

• Characterized by its strong, pungent odor 

3. Therapeutic Uses: 

• Carminative: Relieves flatulence and abdominal discomfort 

• Antispasmodic: Used in colic and gastrointestinal spasms 

• Expectorant: Helps in cough and bronchitis 

• Anthelmintic: Expels intestinal worms 

• Traditional uses in hysteria, asthma, and nervous disorders 

4. Commercial Application: 

• Used as a spice and flavoring agent in Indian cuisine 

• Ingredient in digestive formulations like Hingwashtak churna 

• Included in herbal products for gastric and respiratory disorders 

 

Conclusion: 

Caffeine and asafoetida are valuable natural products with broad therapeutic and commercial utility. Caffeine acts primarily on the central nervous system, while asafoetida supports gastrointestinal and respiratory health, reflecting the diversity of phytochemicals in traditional and modern healthcare. 

51. Write down the method of isolation, identification and analysis of Atropine. 

 

1. Source: 

• Botanical name: Atropa belladonna, Datura stramonium, Hyoscyamus niger 

• Family: Solanaceae 

• Part used: Leaves and roots 

• Active compound: Atropine (a tropane alkaloid) 

 

2. Method of Isolation: 

a. Extraction: 

• Plant material is dried and powdered. 

• Extracted using acidified water or ethanol (pH adjusted to around 2 with dilute HCl). 

• The aqueous acidic extract is filtered and made alkaline using ammonia or NaOH. 

b. Liquid-Liquid Extraction: 

• Alkaloids (in free base form) are extracted with chloroform or ether. 

• The organic layer is separated and evaporated to obtain crude atropine. 

c. Purification: 

• Crude product is purified by crystallization using alcohol or by column chromatography using silica gel. 

 

3. Identification of Atropine: 

a. Vitali–Morin Test (Specific): 

• Add fuming nitric acid to atropine, evaporate to dryness. 

• Add alcoholic potassium hydroxide. 

• Result: Violet color develops → confirms presence of tropane alkaloids. 

b. TLC (Thin Layer Chromatography): 

• Solvent: Chloroform:Methanol (9:1) 

• Spray with Dragendorff’s reagent → orange spot 

c. IR Spectroscopy: 

• Shows peaks for ester group (C=O) and hydroxyl group (–OH). 

d. UV Spectroscopy: 

• Shows characteristic absorption at λmax ~ 258 nm. 

 

4. Analysis: 

a. HPLC (High-Performance Liquid Chromatography): 

• Column: C18 reversed phase 

• Mobile phase: Methanol:water or acetonitrile:buffer mixture 

• Detection: UV at 254–260 nm