Phytochemistry I PGC 504

Study Notes

Pharmacognosy focuses on natural drugs and their scientific description.
Drugs can be derived from natural sources (plants, animals, minerals) or synthesized in labs.
Phytochemistry studies phytochemicals, particularly secondary metabolites in plants.
Secondary metabolites serve protective functions for plants and have healing properties for humans.

Primary metabolites are essential for life and include carbohydrates, proteins, fats, nucleic acids, and vitamins.
Secondary metabolites are unique to specific organisms and have pharmacological activity.

Fresh plant materials are utilized in traditional medicine and flavor industries.
Dried plant materials are used in flavoring, spices, and medicinal drugs.
Acellular products include gums, resins, balsams, and essential oils.
Galenical preparations comprise plant extracts or tinctures for direct use.
Standardized extracts have known concentrations of active ingredients.
Pure compounds are preferred for pharmaceutical formulations due to established quality, safety, and efficacy.

Natural products provide drugs that are challenging to produce synthetically, like opium and antibiotics.
Semisynthetic compounds enhance drug effectiveness or reduce toxicity through modification, such as morphine analogues.
Natural products serve as templates for developing synthetic analogues, e.g., procaine as a local anesthetic.
Starting materials can lead to more potent drugs via chemical modification or biotransformation, exemplified by Baccatin III and Stigmasterol.

Classification is based on biosynthetic origin, solubility, presence of key functional groups, physicochemical properties, and pharmacological activities.

Phenolic Compounds: Include flavonoids and tannins; have hydrophilic properties and at least one aromatic ring.
Terpenoids: Include volatile oils and carotenoids; are lipophilic and classified by isoprene units (monoterpenes, sesquiterpenes, etc.).
Nitrogen-Containing Compounds: Include amino acids and alkaloids; basic compounds that respond positively to ninhydrin or Dragendorff's reagents.
Organic Acids and Lipids: Include simple organic acids and fatty acids; derived from acetate with varying solubility.
Water-Soluble Carbohydrates: Comprise mono- and oligosaccharides and glycosides.
Macromolecules: High molecular weight compounds such as nucleic acids, proteins, and polysaccharides.