FARMACOGNOSIA

This document provides a comprehensive overview of Pharmacognosy, covering definitions, analysis techniques, factors influencing active principles, and medicinal plants affecting various physiological systems.

• Introduction and Definitions: Pharmacognosy studies natural substances (vegetal, mineral) used as medicine, with historical roots. "Droga" refers to parts with high active substance concentration. Analysis involves morphological, microscopic, chemical-physical, and biological methods. Morphological analysis covers leaves, roots, and flowers. Microscopic analysis examines cellular structures and stomata, including the stomatic index. Chemical-physical analysis identifies cellular contents and determines properties like moisture, ash, and viscosity.
• Factors Influencing Active Principles: These include natural (balsamic time, species selection via hybridization or genetic manipulation, environmental conditions like climate and soil) and artificial factors (harvesting and drying processes).
• Drug Preparation: Involves careful harvesting and mondatura (cleaning). Drying (essiccazione) removes water to prevent degradation and enzyme activity, using methods like rack drying, screened greenhouses, dynamic dryers, or sublimation (lyophilization). Enzymatic inhibition can also be irreversible through stabilization or sterilization.
• Quality Control: Essential for ensuring drug quality, performed through autoptic, macroscopic, chemical-physical, and biological analyses, often following a structured analytical sheet.
• Medicinal Plants by System:
  • Autonomic Nervous System:
    • Sympathomimetic: Erythroxylon coca (cocaine, blocks catecholamine reuptake, local anesthetic), Ephedra spp (ephedrine/pseudoephedrine, mixed action, decongestant, bronchodilator).
    • Sympatholytic: Rauwolfia serpentina (reserpine, inhibits dopamine transport, hypotensive, sedative), Claviceps purpurea (ergot alkaloids like ergotamine, ergonovine, acting on various receptors, used for migraine and uterine contractions).
    • Parasympathomimetic: Pilocarpus jaborandi (pilocarpine, glaucoma), Areca catechu (arecoline, vermifuge), Physostigma venenosum (physostigmine, acetylcholinesterase inhibitor, glaucoma).
    • Parasympatholytic: Solanaceae family plants like Atropa belladonna, Hyosciamus niger, and Datura stramonium (atropine, scopolamine, block muscarinic receptors, reducing secretions and inducing mydriasis).
  • Cardiovascular System: Used for congestive heart failure. Digitalis purpurea and Digitalis lanata contain cardenolidic glycosides that inhibit Na+/K+ ATPase, increasing myocardial contractility. Urginea maritima (squill) contains bufadienolidic glycosides with expectorant and diuretic properties, but is toxic.
  • Laxative-Purgative: Includes bulk-forming agents like Althea officinalis and Malva sylvestris (mucilages) and stimulant laxatives with anthraquinonic glycosides from Rhamnus purshiana (cascarosides), Rhamnus frangula (glucofrangulin), Rheum officinale (sennosides), Cassia alessandrina (sennosides), and Aloe spp (barbaloin). Ricinus communis acts via ricinoleic acid, a non-anthraquinonic mechanism.
  • Antimalarial / Bitter Tonic: Cinchona succirubra (quinine, quinidine) is known for its antimalarial and eupeptic (bitter-tonic) actions.
  • Anti-hyperplastic: Serenoa repens (lipidosterolic extract) is used for benign prostatic hyperplasia, exhibiting anti-androgenic, anti-inflammatory, and alpha1-blocking effects.
  • Dyslipidemia: Red fermented rice (produced by Monascus purpureus) contains monacolin K, an HMGCoA reductase inhibitor, used for cholesterol reduction.
  • Anti-inflammatory: Salix spp (willow bark) provides salicylic glycosides that act as anti-inflammatory agents via COX inhibition. Harpagophytum procumbens (devil's claw) contains iridoid glycosides with analgesic and anti-inflammatory effects through lipoxygenase inhibition.
  • Respiratory System:
    • Expectorants: Cephaelis ipecacuanha (emetine, cephaeline), Polygala senega (saponins), and Glycyrrhiza glabra (glycyrrhizin, saponins) help clear mucus.
    • Balsamic/Sedative: Hedera helix (saponins), Eucalyptus globulus (eucalyptol), Mentha x piperita (menthol), Matricaria recruita (bisabolol, chamazulene), and Valeriana officinalis (borneol, valtrate, with GABAergic action) reduce bronchial secretions or provide sedative effects.

  The document details the active principles, mechanisms of action, traditional and modern uses, and potential side effects or contraindications for each plant.