OIA2007 INTRODUCTION TO PHARMACOGNOSY

Pharmacognosy

The study of medicinal plants and natural substances used in medicine.

Crude Drug

Naturally occurring substances (e.g., plants, animals, minerals) used in medicine without modification.

Active Constituent

The bioactive chemical component in a medicinal plant (e.g., alkaloids, flavonoids).

Phytochemistry

The branch of chemistry dealing with plant-derived chemical compounds.

Ethnobotany

The study of how different cultures use plants for medicine.

Pharmakon (Greek Origin)

"Pharmakon" means drug, and "Gignoso" means knowledge.

First Herbal Pharmacopoeia

London Pharmacopoeia (1618) was one of the earliest references for herbal drugs.

Papyrus Ebers (Egypt, 1550 BC)

One of the earliest medical texts listing medicinal plants.

Ayurveda (India, 2500–600 BC)

Traditional Indian system of medicine using plant-based treatments.

Unani Medicine (Islamic Origin, 980–1037 AD)

Ancient system of medicine integrating Greek and Islamic knowledge.

Plant Sources

Leaves, roots, bark, flowers, fruits (e.g., Cinchona bark for quinine).

Animal Sources

Glands, hormones (e.g., Insulin from the pancreas).

Mineral Sources

Metals, salts (e.g., Iron for anemia, Zinc oxide for wound healing).

Marine Sources

Algae, mollusks (e.g., Taxol from Pacific yew for cancer treatment).

Alkaloids

Nitrogen-containing compounds (e.g., Morphine, Quinine).

Flavonoids

Plant pigments with antioxidant properties (e.g., Catechin, Rutin).

Glycosides

Sugar-bound bioactive molecules (e.g., Digoxin from Digitalis).

Terpenoids

Largest class of natural compounds (e.g., Menthol from mint).

Tannins

Polyphenols with astringent properties (e.g., Tea, Oak bark).

Digitalis Purpurea (Foxglove)

Constituent: Digoxin

Use: Treats heart failure.

Papaver Somniferum (Opium Poppy)

Constituent: Morphine, Codeine

Use: Pain relief, cough suppressant.

Cinchona Bark

Constituent: Quinine

Use: Treats malaria.

Atropa Belladonna (Deadly Nightshade)

Constituent: Atropine

Use: Antimuscarinic, dilates pupils.

Rauwolfia Serpentina

Constituent: Reserpine

Use: Antihypertensive.

Macroscopic Examination

Observing the size, shape, color, texture, and odor of crude drugs.

Microscopic Examination

Identifying plant tissues and cell structures.

Chemical Testing

Using qualitative tests to detect active constituents.

Chromatographic Analysis

TLC, HPLC, GC-MS used for identifying chemical profiles.

Pharmacological Testing

Evaluating the biological effects of plant extracts.

British Herbal Pharmacopoeia

A reference for herbal drug standards.

WHO Guidelines

Provides quality control, safety, and efficacy standards for herbal medicines.

Adulteration

Presence of inferior, substituted, or contaminated plant material.

Standardization

Ensuring consistent active ingredient concentration in herbal drugs.

Good Agricultural and Collection Practices (GACP)

Ensures proper cultivation, harvesting, and storage of medicinal plants.

Extraction Methods

Maceration, percolation, Soxhlet extraction used for isolating plant chemicals.

Lead Compound Discovery

Screening plant extracts for new drug candidates.

Examples of Drugs Derived from Plants

Paclitaxel (Taxol) from Taxus brevifolia (cancer drug).

Vincristine, Vinblastine from Vinca rosea (anticancer drugs).

Herb-Drug Interactions

Example: Grapefruit juice can inhibit drug metabolism, increasing toxicity.

Phytopharmaceuticals & Nutraceuticals

Functional foods with health benefits (e.g., Green tea extract for antioxidants).

Future of Pharmacognosy

Increased biotechnological approaches, plant-derived drug synthesis, and global standardization.