Category: Medicinal Plant Science

Secondary metabolites Unlike primary metabolism (growth), secondary compounds often defend against herbivores and pathogens but become pharmacologically active in humans at controlled doses. Major classes Alkaloids — nitrogen-containing (morphine, caffeine, quinine) Terpenoids — built from isoprene units (menthol, artemisinin) Phenolics — flavonoids, tannins, coumarins Glycosides — sugar-bound active aglycones released by metabolism Biosynthesis context Production…

Documenting traditional knowledge Ethnobotany links plant use to culture. Ethical frameworks require informed consent, community benefit-sharing, and respect for indigenous intellectual property. Methods Structured interviews with traditional healers Participatory mapping of gathering areas Voucher specimens deposited in herbaria with use notes Quantitative use-value indices ranking plant importance Validation pathway Ethnobotanical leads → phytochemical screening →…

From field to pharmacy Variable growing conditions cause batch differences. GMP (Good Manufacturing Practice) ensures traceability and safety. Testing requirements Identity — morphology, microscopy, DNA barcoding Purity — heavy metals, pesticide residues, microbial limits Potency — marker compound quantification (HPLC, GC) Stability — shelf-life under defined storage Adulteration Economically motivated substitution (cheaper plants sold as…

Solvent selection Polar solvents (water, ethanol) extract flavonoids and glycosides. Non-polar solvents (hexane) extract oils and waxes. Sequential extraction uses increasing polarity. Techniques Maceration — soak plant material at room temperature. Soxhlet — continuous solvent circulation. Supercritical CO₂ — tunable pressure for clean oil extracts. Ultrasound-assisted — disrupts cells to improve yield. Safety Work in…

Plants are not automatically safe Many medicinal plants contain toxic compounds at high doses (e.g., pyrrolizidine alkaloids, cardiac glycosides). Interaction with pharmaceuticals adds risk. Risk assessment Acute toxicity (LD50 in models) Chronic exposure studies Hepatotoxic and nephrotoxic monitoring Reproductive and developmental effects Labeling Contraindications, maximum daily dose, and pregnancy warnings required for commercial products in…

Why standardization Raw herb quality varies. Standardized extracts guarantee minimum marker compound content per dose. Marker selection Choose chemically stable compounds correlated with biological activity. Example: hypericin/hyperforin in St. John’s wort (with ongoing debate on active principles). Analytical methods HPLC with UV or mass spectrometry detection is standard. Calibration curves from pure reference standards ensure…