BP105T Unit 3 – Quality Control & Evaluation of Crude Drugs
Unit 3 details Good Agricultural and Collection Practices (GACP) for medicinal plants. It covers environmental cultivation parameters (altitude, temperature, soil, fertilizers, Plant Growth Regulators), seasonal harvesting rules, post-harvest drying techniques (sun, shade, oven, vacuum/freeze-drying), garbling, packaging, and warehouse preservation.
📋 Prescribed Syllabus Topics
📖 Detailed Lecture Notes & Solved Examples
11. Cultivation Factors & Plant Growth Regulators (PGRs)
Dedicated Webpage➔While wild collection (unorganized harvesting from forests) leads to species depletion and batch-to-batch chemical inconsistency, controlled Cultivation ensures uniform botanical purity, higher yields of active secondary metabolites, year-round supply, and adherence to Good Agricultural Practices (GAP). Environmental factors influencing phytoconstituent synthesis include Altitude (e.g. Cinchona thrives at 1000-2000 m; Tea at 1500 m), Temperature (e.g. Cardamom requires humid tropical shade; Pyrethrum requires cool climates), Rainfall, Soil type (loamy, sandy, clay) and Soil pH. Plant Growth Regulators (PGRs) are organic phytohormones that modify plant physiological processes at minute concentrations.Jungle se lene ke bajaye kheti (Cultivation) karne se pure aur high-potency dawaiyan milti hain. Cinchona pahado par (1000-2000m) achha ugta hai. Auxins jadh (roots) nikalne me madad karte hain, Gibberellins paudhe ki lambai aur pattiyon ka size badhate hain, aur Cytokinins tissue culture me cell division karate hain.
▶Classes and Pharmacognostic Applications of Phytohormones
Using plant growth regulators to enhance secondary metabolite yield.
- •Altitude: Cinchona (1000-2000 m for high Quinine content), Clove (sea level up to 900 m), Opium (temperate plains).
- •NPK Fertilizers: Nitrogen enhances leaf biomass in foliage drugs (Digitalis, Senna); Phosphorus promotes root growth in underground drugs (Rauwolfia, Ginger); Potassium enhances starch and alkaloid synthesis.
- •Bio-fertilizers: Nitrogen-fixing Rhizobium, Azotobacter, and Mycorrhizal fungi.
22. Harvesting Rules, Drying Methods, Garbling & Packaging
Dedicated Webpage➔The therapeutic potency of crude drugs depends critically on harvesting at the precise developmental stage when active secondary metabolites reach their seasonal and diurnal peak. Post-harvest processing involves: (1) Garbling / Dressing (manual removal of extraneous matter, dirt, discolored leaves, and unwanted plant parts), (2) Washing (for underground roots/rhizomes), (3) Drying (reducing moisture content below 8-10% to inactivate destructive endogenous plant enzymes like glycosidases and esterases and prevent bacterial/mold proliferation), and (4) Packaging in air-tight, moisture-proof containers.Pattiyan phool khilne se pehle todi jaati hain jab unme chemical sabse jyada hota hai. Chhaal (Bark) spring ya barsaat me nikaalte hain jab ped se aasani se chhilka utar jata hai. Digitalis leaves ko hamesha 60°C se kam par sukhate hain taaki uske glycoside enzymes se toot na jayein. Sookhne ke baad moisture 8-10% se kam hona chahiye.
▶Pharmacopoeial Harvesting Schedule for Anatomical Plant Parts
Optimal collection stages according to Good Agricultural Practices.
| Plant Part | Optimal Collection Timing | Recommended Drying Method | Critical Precaution |
|---|---|---|---|
| Leaves (Senna, Digitalis) | Before flowering season | Shade drying / Oven (< 60°C) | Prevent glycoside-hydrolyzing enzymatic degradation |
| Barks (Cinchona, Cinnamon) | Spring / Early rainy season | Sun drying / Shed drying | Quill formation; avoid mold in damp storage |
| Roots (Rauwolfia, Ginger) | Autumn / Winter after aerial decay | Sun drying after thorough washing | Remove foreign soil and dirt thoroughly |
| Flower Buds (Clove) | Before buds open into flowers | Sun drying on clean mats | Handle gently to retain central crown/clove head |
| Latex (Opium) | Late afternoon incision of unripe capsule | Spontaneous air evaporation on capsule | Collect scrapings early next morning before dew |
- •Sun Drying: Suitable for hardy, non-volatile, stable drugs (e.g., Ginger, Turmeric, Fennel).
- •Shade Drying: Mandatory for volatile oil-bearing aromatic drugs (Peppermint, Clove) and thermolabile glycosides (Digitalis) to prevent volatilization and photo-degradation.
- •Oven / Dehydration Drying: Rapid moisture removal at controlled temperatures (Digitalis leaves dried strictly below 60°C to preserve cardiac digitoxin glycosides).
- •Freeze-Drying (Lyophilization): Sublimation of ice under high vacuum for thermolabile biologicals (Enzymes, antibiotics, Papain).
- In a 10-mark question, describe the complete post-harvest processing of crude drugs: Garbling, Washing, Drying (Sun, Shade, Oven, Lyophilization), Packaging, and Storage.
- List the harvesting rules for leaves, barks, roots, and flower buds with pharmacopoeial drug examples.