Crude Drugs and Coumarins Quiz

Pharmacognosy Definition and Introduction

• Pharmacognosy is the study of drugs derived from natural sources.
• Natural sources include plants, animals, microorganisms, and minerals.
• The word "pharmacognosy" comes from Greek words: pharmakon (drug) and gnosis (knowledge) or gignosco (to acquire knowledge).
• It's a highly interdisciplinary field of science, undergoing a significant change in recent years.
• It's a major area of pharmaceutical education.
• The American Society of Pharmacognosy (ASP) defines it as the study of physical, chemical, biochemical, and biological properties of drugs or substances derived from natural sources.
• It plays a key role in the discovery and development of new drugs and therapies, acting as a basis for Pharmacy development.

History of Pharmacognosy

• The history of pharmacognosy is as old as medicine.
• The Ebers Papyrus (1500 BC) described medicinal plants, animal, and human anatomy used by ancient Egyptians.
• Hippocrates (460-370 BC), the "father of medicine", described human anatomy and physiology, using medicinal plants for treatment.
• Aristotle (384-287 BC) studied animals, and Theophrastus (370-287 BC), his student, studied plants.
• Dioscorides (AD 78) compiled a medical encyclopedia, "De Materia Medica", describing 600 therapeutic medicinal plants.
• Pliny the Elder (AD 23-79) wrote "Natural History," a comprehensive compendium of Roman knowledge, including medicine.
• Galen (AD 131-200) described methods for preparing preparations containing active constituents from plant and animal sources ("Galenical pharmacy").
• Johann Adam Schmidt (1811) and later, Sydler in 1815 in his work "Analecta pharmacognostica," are credited with first introducing the term "pharmacognosy".
• Crude drugs are the dried, unprepared material of plant, animal, or mineral origin.

Relationship with Other Subjects

• Pharmacognosy is interdisciplinary, encompassing botany, ethnobotany, medical anthropology, marine biology, microbiology, herbal medicine, chemistry, biotechnology, phytochemistry, pharmacology, pharmaceutics, clinical pharmacy, and pharmacy practice.
• Key subdivisions include: Medical ethnobotany, ethnopharmacology, phytotherapy, phytochemistry, zoopharmacognosy, Pharmacognosy- Biotechnology, herbal interactions, and marine pharmacognosy.

Marine Pharmacognosy

• Marine pharmacognosy investigates the medicinal properties of marine organisms (bacteria, viruses, algae, fungi, and sponges).
• Many antimicrobial, antiviral, antiparasitic, and anticancer drugs originate from marine organisms.
• Marine flora and fauna are a significant source for new molecular entities.
• Marine natural products consist of diverse chemical classes (e.g., terpenes, shikimates, polyketides, acetogenins, peptides, alkaloids).

Development of Marine Drugs in Modern Times

• Scientists have systematically investigated oceans for medicinal resources since the mid-20th century.
• Examples include the isolation of Holothurin toxin from a Bahamian Sea Cucumber (Actynopyga agassizi) in the early 1950s.
• Researchers have isolated numerous novel compounds with biological activities from marine organisms, mainly focused on their secondary metabolites as chemical defenses against predators.
• Methods for collecting marine drugs include: beach combing, wading, snorkeling, dredging, coring, scuba diving, and submersibles.
• Drying methods, such as lyophilization (freeze drying), are used before extraction.

Selected Example of Marine Natural Products

• Various examples are provided of marine sources (marine sponge, marine fungi, Marine Cone Snail, Marine Nemertine worm, Bryozoan, sea squirt, sea slug, and sea sponge) producing drug products in various stages of development/applications.

Scope of Pharmacognosy

• Pharmacognosy encompasses the study of plants, and more recently, various microbes (bacteria, fungi, etc.) and marine organisms.
• Its scope includes phytochemistry, microbial chemistry, biosynthesis, biotransformation, chemotaxonomy, biotechnology, and other biological and chemical sciences.
• The definition includes aspects like identifying and evaluating drugs. The field involves a broad understanding of drugs, their use, and their effects on humans and other animals.

Function of a Pharmacognosist

• Identifying the drug sources.
• Determining morphological characteristics.
• Investigating potency, purity, and admixture.
• Planning and designing the cultivation of medicinal plants.
• Outlining processes for collection, drying, and preservation.
• Understanding the active constituents, their chemistry, and applications.

Some Basic Terminologies in Pharmacognosy

• Drugs can be natural, semi-synthetic, or synthetic.
• Crude drugs are naturally derived materials (plants, animals, or minerals). They can be organized (cellular) or unorganized (acellular). Divided into organized or unorganized drugs. Organized drugs have characteristically contained cellular structures (e.g., Digitalis, Cinchona, and clove). Unorganized drugs do not contain cellular structures (e.g., Aloe, Agar, colophony, beeswax, castor oil, and opium).
• Vegetable drugs refer to those derived from plants.
• Non-vegetable drugs are derived from animals or minerals.

Taxonomic (Biological) Classification

• Based on botanical and zoological systems. Used for identifying and describing the source of drugs.
• Classification involves division, class, order, family, genus, and species.

Morphological Classification

• Organised and unorganised drugs are classified by the part of the plant used (e.g., seeds, leaves, bark, roots, rhizomes, flowers, fruits).

Chemical Classification

• Classified based on the chemical nature of the primary constituent.
• Groups drugs with similar chemical compositions that may have similar pharmacological actions together.
• Examples include glycosides, alkaloids, volatile oils, lipids, carbohydrates, proteins, enzymes, vitamins, and hormones.

Pharmacological (Therapeutic) Classification

• Groups drugs according to their primary pharmacological actions or therapeutic uses (e.g., laxatives, bitters, cardiac tonics, etc.).

Chemotaxonomic Identification

• Characterized based on distinctive chemical compounds (e.g., secondary metabolites).
• This method aids in understanding the biological relationships and evolution among plants.
• Molecular techniques, like DNA analysis and amino acid sequencing, are becoming increasingly important for this work.

Adulteration and Evaluation of Drugs

• Adulteration involves adding impurities to a drug, accidentally or intentionally. Evaluation determines purity, identity, and quality.
• Methods include organoleptic, microscopic, physical, chemical, and biological evaluation to identify adulterants and evaluate quality.

Secondary Metabolites

• Secondary metabolites are chemical compounds produced by plants as by-products of their normal metabolic activities.
• They play various roles in plant medicine like defense mechanisms against predators, microbial attacks, or herbivory.
• Include compounds such as flavonoids, alkaloids, terpenoids, steroids, tannins, saponins, glycosides, and anthraquinones.
• Naturally occurring, can be modified to create potent drugs.

Anthracene (Anthraquinone) Glycosides

• Found in dicots and monocots.
• Characterized by their laxative action in humans and animals.
• Consist of a core anthracene structure with attached carbohydrate molecules (glycones).
• Examples include emodin, rhein, and chrysophanol.
• Their basic structure is based on anthracene.

Coumarin Glycosides

• Coumarins are phenolic compounds found in various plants.
• Usually present as glycosides (combined with sugar molecules, often glucose).
• Some are used in medicine as precursors for anticoagulants notably Warfarin, and in the fragrance/flavouring industry.
• Examples include Umbelliferone, Umbellic acid, and Herniarin.

Asafoetida

• Oleo-gum resin exudation from various Ferula species.
• The volatile oil gives it a "garlic-like" odour.
• Consists of volatile oils, resins, and gums.
• Used in flavourings and traditional medicine.
• Contains chemical constituents like umbellic acid, umbelliferone, and ferulic acid.

Other Plants Containing Glucosinolates

• Include cabbage, white mustard, black mustard.
• Glucosinolates are sulfur-containing compounds.
• They have defensive functions(irritant effect and defence against pests/diseases).
• Responsible for the pungent odour of many cruciferous plants.

Black and White Mustard

• Both are from the Cruciferae family.
• Active constituents: glucosinolate glycosides (sinigrin and sinalbin), along with the enzyme myrosin.
• Mustard oils play a defense mechanism role and are also irritant, stimulant, diuretic, and emetic.
• Used in various food applications, and as spices.

Furanocoumarins

• Toxic compounds found in various plants.
• Important photoactive agents (react with UV light).
• Examples include psoralen, bergaptol and bergamottin.

PUVA (Photochemotherapy)

• Combination therapy using psoralens and UVA radiation to treat skin conditions.
• Psoralens sensitise the skin to UVA to treat the skin condition.

Cyanogenic Glycosides

• Produce Hydrogen Cyanide upon hydrolysis.
• Found in plants like cassava and some species of Prunus(e.g. almonds).
• Often defensive or provide characteristics to plants.
• Example include Amygdalin, a primary cyanogenic glycoside from apricot kernels.

Bavchi

• Fruits and seeds of Psoralea corylifolia plant (belonging to the Legume family).
• Use as an aphrodisiac, antibacterial, and tonic agent.
• Contains chemical constituents including coumarin compounds.

Ammi

• Fruits of Ammi majus plant (belonging to the Umbelliferae family).
• Contains chemical constituents like furanocoumarins.
• Uses in the treatment of vitiligo (piebald skin) and psoriasis.

Visnaga

• Fruits of Ammi visnaga plant.
• Contains chemical constituents like khellin and visnagin.
• Medicinal use to treat kidney stones pain for its muscle relaxant properties, antispasmodic effects on the bronchial muscles, and related use as treatment of asthma.

Bergamot

• Essential oil from various Monarda species (of Lamiaceae family).
• Contains chemical constituents like furanocoumarins and terpenes.

Hierochloe odorata

• Commonly known as sweet grass.
• Found in North America.
• Contains coumarins, primarily coumarin and its derivatives.
• Used as an incense to scent churches and for flavouring food.

Test your knowledge on crude drugs, their sources, and classifications in this informative quiz. Explore questions about acellular and cellular drugs, the botanical classification of crude plant drugs, and the industrial uses of coumarins. Perfect for students studying pharmacognosy and natural products.