1. INTRODUCTION TO PHARMACOGNOSY
Course: Pharmacognosy-I
Course Instructor: Nishat Jahan

2. Pharmacy
Pharmacy refers to the profession which is concerned with the handling of all aspects of chemical substances referred to as medicine or drugs.
This includes knowledge of source (whether natural & synthetic), physical & chemical properties, good and bad effects on living organisms (including man), dose & dosage forms, formulation, compounding & manufacturing, quality control & assurance, storage, sale and finally law & ethics governing the manufacture, import, export & usage of drugs or poisons.

3. Pharmacist
Pharmacists, also known as druggists are healthcare professionals who practice in pharmacy, the field of health sciences focusing on safe and effective medication use.
The role of the pharmacist has shifted from the classical "lick, stick, and pour" dispensary role (that is, "lick & stick the labels, count the pills & pour liquids"), to being an integrated member of the health care team directly involved in patient care.

4. Pharmacists undergo university-level education to understand biochemical mechanisms of action of drugs, drug uses and therapeutic roles, side effects, potential drug interactions and monitoring parameters. This is mated to education in anatomy, physiology, and pathophysiology.
Professional interpretation and communication of this specialized knowledge to patients, physicians and other health care providers are functions which pharmacists provide, and are central to the provision of safe and effective drug therapy.

5. What is Pharmacognosy?
The term 'pharmacognosy' was first coined and used by C.A. Seydler in 1815 in a small book he wrote on crude drugs, entitled "Analecta Pharmacognostica". It was derived from two Greek words: pharmakon, which means 'a drug', and gnosis, which means knowledge of, or gignosco, which means 'to acquire knowledge of’. Thus the literal meaning of pharmacognosy is: knowledge of drugs, or to acquire knowledge of drugs. Thus Pharmacognosy may be defined as the objective study of crude drugs and related substances of natural origin to acquire knowledge about their nature and properties. It may also be defined as an applied science which is concerned with acquiring knowledge of all aspects of crude drugs and other natural substances of pharmaceutical importance by the application of various scientific disciplines.

6. According to the American Society of Pharmacognosy-
Pharmacognosy is the study of physical, chemical, biochemical & biological properties of drugs, drug substances or potential drugs or drug substances of natural origin as well as the search for new drugs from natural sources.

7. In other words, it may be said that Pharmacognosy is an important branch pharmacy, which deals with the scientific study of the structural, physical, chemical, biochemical and sensory characteristics of crude drugs and related substances of plant, animal and mineral origin. It also includes a study of their history, distribution, cultivation, collection, identification, preparation, evaluation, preservation, use and commerce.

8. WHAT DO PHARMACOGNOSISTS “DO”?
Isolation & characterization of “active constituents”
Characterization of the pharmacology of crude extracts & active constituents
Evaluation of quality of natural medicines
Interdisciplinary relationship with ethnobotany & ethnopharmacology

9. Ethnobotany
Ethnobotany is the study of the relationship between people and plants. This interdisciplinary field includes studying plants:
as wild foods and as agricultural crops;
as constructs for houses and modes of transportation;
as baskets, pottery, and art;
as clothing and types of weaving;
as medicines and alternative methods for healing;
and in the context of cultural myths and religious ceremonies.
Research topics address more complex issues, including the cultural consequences of the extinction of a particular plant species on the diet of a culture,
impacts of acculturation on a culture's uses of plants, and the transmission of ethnobotanical knowledge from one generation to the next.

10. Acculturation
*Acculturation= The process of adopting the cultural traits of another group

11. Ethnopharmacology is the scientific study correlating ethnic groups, their health, and how it relates to their physical habits and methodology in creating and using medicines.

12. Scope of Pharmacognosy
Pharmacognosy occupies an important place in pharmacy as it deals with the collection, identification, preparation and extraction of a large group of drugs obtained from natural sources, which are used both in orthodox and traditional medicine.
The knowledge of the action of a drug (pharmacology) can be utilized successfully only when the identity, physical nature and chemical constituents of the drug are well known, and pharmacognosy supplies this information.

13. Solubility, reactivity, stability, toxicity, dosage, availability, purity, yield, methods of isolation, purification and identification of the chemicals of natural origin are studied in pharmacognosy, which supplies the general information about them needed by all practicing pharmacists.
Thus pharmacognosy, the science of drugs of natural origin, has become a discipline of increased significance in the curriculum of pharmaceutical education. In fact, pharmacognosy formed the basis on which other branches of pharmacy developed. Pharmacology, Pharmaceutical Chemistry and Pharmaceutics are all manifestations and ramifications of this basic science of drugs.

14. Chemical nature and properties of a chemical substance can be studied and understood, or it can be synthesized or its activity can be modified or improved by a pharmaceutical chemist if he possesses a good knowledge of its source, occurrence and method of isolation and state of purity.
Formulation and actual preparation of a pharmaceutical product (pharmaceutics) are dependent on a number of properties, such as solubility, stability, reactivity, etc. of the ingredients. This type of information on substances of natural origin is available to the pharmacist if he possesses a good knowledge of pharmacognosy.

15. Price of a pharmaceutical product containing natural substances is influenced by the methods of collection, curing, drying and assaying of the ingredients, which are dealt with in pharmacognosy.
In addition to the various branches of pharmacy, pharmacognosy is closely related to botany and plant chemistry by the fact that both of them developed as a result of man's interest in plants as sources of food and medicine.
Pharmacognosy also shares some grounds with biochemistry. physiology. enzymology, food technology and a number of other fields of science. This wider scope of pharmacognosy entitles pharmacognosists to specialize in taxonomy, anatomy, morphology, phytochemistry, cultivation and conservation of medicinal and poisonous plants.

16. Definitions
Drug: The term 'drug' refers to any article, whether natural or synthetic having therapeutic and medicinal properties and used in the diagnosis, cure, mitigation, treatment or prevention of diseases in man and other animals.

17. Crude drug
Crude drugs are natural substances of plant, animal or mineral origin, which possess therapeutic properties and pharmacological actions and which have undergone no treatment other than collection and drying.

18. Traditional medicine
Traditional medicines, when referred to the medicinal products, represent a group of medicinal preparations, which are prepared by ancient technology and according to the age-old wisdom of the medicinal virtues of natural substances and concept of disease, handed down from generation to generation.

19. Herbal Medicine: The term 'Herbal medicine' refers to some medicinal preparations or compounds which are made of one or more plant drug(s) or medicinal plant(s) or its (their) parts and organs and are used in the treatment, cure, mitigation and management of various physical and mental diseases or ailments and external or internal injuries of man and other animals.

20. Natural products/substances: They can be
Entire organism (plant, animal, organism)
Part of an organism (a leaf or flower of a plant, an isolated gland or other organ of an animal)
An extract or an exudate of an organism
Isolated pure compounds

21. Materia Medica: The term Materia Medica literally means materials of medicine and refers to medicinal substances and products derived from natural sources.
Dioscorides, a Greek physician, wrote a book “De Materia Medica”- he described 600 plants that were known to have medicinal properties.

22. Formulary
Formulary is a publication, which contains a list of patent medicines with their
Ingredients and brief notes on their pharmacological properties,
and therapeutic uses,
published by the relevant authority of a country as a guide for practitioners of medicine and pharmacy.
BDNF (Bangladesh National Formulary), BNF (British National Formulary), NF (American National Formulary) are some of the examples of such Formularies.

23. What is patent?
A government license that gives the holder exclusive rights to a process, design or new invention for a designated period of time. Applications for patents are usually handled by a government agency.

24. Pharmacopoeia
Pharmacopoeia is an official publication, which lists various drugs and therapeutic agents of current use with their monographs and specifies tests and standards for them.
It includes description, formulation, analytic composition, physical constants, main chemical properties used in identification, standards for strength, purity, and dosage, chemical tests for determining identity and purity, etc. for a particular drug/ preparations.
They are usually published under governmental jurisdiction.
Many countries publish their own pharmacopoeias listing all the drugs and therapeutic agents used in that country and specifying required standards for them. British Pharmacopoeia (BP). United States Pharmacopeia (USP)

25. Pharmacopoeia
They differ from formularies in that they are far more complete;
formularies simply list drugs or collections of formulas for the compounding of medicinal preparations.
However, sometimes the terms "pharmacopoeia" and "formulary" are used interchangeably.
In addition to serving as current reference sources, pharmacopoeias and formularies provide an historical record of pharmacy practice, drug use, and drug availability.

26. Monograph:
The descriptive material pertaining to any drug or therapeutic agent or preparation included in the pharmacopoeia is known as the monograph.
The monograph of a crude drug generally includes the following information on the drugs: official title, synonym, definition, rubric, description, special conditions of collection or preparation for the market, identity tests, tests for adulterants, method of assay, storage requirements, amount of foreign organic matters, uses and doses.

27. Official drug: Any substance or drug (crude or prepared), which is included in the current issue of the pharmacopoeia of a country and is officially used for therapeutic purposes, is called an 'official drug'.
Unofficial drug: A drug, which has once been recognized as a drug in the pharmacopoeia, but not included in the current issue of the pharmacopoeia or any official Drug literature, is designated as an 'unofficial drug'.
Non-official drug: A non-official drug is a substance, which possesses some medicinal properties and is unofficially used for therapeutic purposes, but has never been included as a therapeutic item in the pharmacopoeia or any official Drug literature of any country.

28. Constituents: These are chemical substances that are present in the cells of some plant or animal organs. Constituents that exert some physiological or pharmacological actions on living organisms are referred to as 'active constituents' or 'active principles'.
Extractive: The crude mixtures of chemical constituents that are removed from plant or animals by various extraction processes are called ‘extractives’.
Secondary metabolites: These are substances synthesized or produced as by-products by plants during their normal metabolic activities. Apparently they are of no primary use to the plant. They are therefore also regarded as 'waste products' of metabolism, which are usually accumulated in some parts of the plant and most often exert physiological activity on living organisms.
They protect plants against being eaten by herbivores and against being infected by microbial pathogens.
They serve as attractants (odor, color, taste) for pollinators and seed-dispersing animals.
They function as agents of plant-plant competition and plant-microbe symbioses.

29. Flora: The term flora refers to the plant population of a particular geographical area or country.
Indigenous: Plants and animals growing or living in their native countries are said to be indigenous to those regions.
Naturalised: Plants or animals are said to be naturalised when they grow or live comfortably in a foreign land or in a locality other than their native homes.