Medicinal Plants Chapter 1 Fall 2024 PDF

Medicinal Plants Introduction (Chapter 1) By: Haidy Ashraf Mohamed Lecturer of Pharmacognosy  Weight of Assessments Assessment Marks method Midterm exam (10 Nov.) 15 Marks Practical exam 25 Marks (Week 11&1...

Medicinal Plants Introduction (Chapter 1) By: Haidy Ashraf Mohamed Lecturer of Pharmacognosy  Weight of Assessments Assessment Marks method Midterm exam (10 Nov.) 15 Marks Practical exam 25 Marks (Week 11&12) (Spots +Powder) Final written exam (13 Jan.) 50 Marks Oral exam (13 Jan.) 10 Marks Total 100 Marks  Aims of the Course The course provides the students with sufficient knowledge to prepare and identify drugs from the farm to the pharmaceutical forms. The course includes information concerning dusting powders, plant cytology, histology and medicinal leafy plants and their taxonomy. In this course, the student will study a general introduction about the history of medicinal plants, importance of natural products, preparation of natural products-derived drugs including collection, drying, packaging, storage and adulteration. The course will address the binomial system and discuss the plant taxonomy of certain families. The students will be able to recognize different classes of secondary metabolites. The course will also sort the pharmacologically active compounds in certain official medicinal leafy plants according to their WHO monographs.  Learning outcome (LOs) 1- History of Pharmacognosy and folk medicine, principles of general Pharmacognosy, definitions. 2- Cultivation of medicinal plants, Collection of drugs from wild plants, Propagation of medicinal plants. 3- Factors affecting plant growth, extrinsic factors, organic manures, essential elements supplied by the soil. 4- Factors affecting plant growth, intrinsic factors (plant growth hormones). 5- Preparation of crude drugs from plants, factors affecting drug collection, natural and artificial drying.  Learning outcome (LOs) 6- Changes occurring during drying, packing of drugs. 7- Factors responsible for deterioration of drugs during storage (physiochemical and biological). 8- Adulteration of drugs and types of adulteration with selective examples. 9- Dusting powders, starchy and non- starchy. 10- Primary and secondary plant metabolites & classification of vegetable drugs, Binomial system and origins of drugs. 11- Plant Taxonomy with example of selected families. 12- Active constituents and pharmacological activity of certain leafy plants according to WHO monograph.  Medicinal Plants ▪ A medicinal plants is a plant that have a similar properties as conventional pharmaceutical drugs which used by human to either care or lessen symptoms from an illness with no or minimal side effects.. A pharmaceutical drug is a drug that is produced in a laboratory to cure or help an illness. ▪ The term “medicinal plant” include various types of plants used in herbalism ("herbology" or "herbal medicine"). It is the use of plants for medicinal purposes, and the study of such uses.  Folk Medicine Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the era of modern medicine. Folklore treatment of certain diseases derived from trial-and-error methods.  Pharmacognosy Pharmacognosy is the study of medicinal plants and other natural substances as sources of drugs. The word "pharmacognosy" is derived from two Greek words: pharmakon (drug), and gnosis (knowledge). The term "pharmacognosy" was used for the first time by the Austrian physician Schmidt in 1811 and by Anotheus Seydler in 1815 in a thesis titled Analecta Pharmacognostica to describe medicinal plants.  Pharmacognosy Pharmacognosy is an applied science that deals with the biologic, biochemical, and economic features of natural drugs and their constituents. Hence, Pharmacognosy is the study of crude drugs (unprocessed drugs) from natural sources including plants (Neem, Saffron, Clove), animal (Honeybee, bee wax), mineral (chalk, bentonite, talc), marine (sponges, red algae, agar) sources and their constituents. Function of a Pharmacognosist: 1. Identification of sources of drugs. 2. Determination of morphological characters. 3. Investigation of potency, purity and admixture. 4. Planning and devising of cultivation of medicinal plants. 5. Prescription of the detail processes of collection, drying and preservation of drugs. 6. Knowledges of active constituents, their chemical nature; determination and reactions. Where does the medicine come from? They are of two main categories natural origin (crude drugs) or synthetic origin. Crude drugs (Raw drugs): - Drug that are obtained from natural sources like plants, animals, marine and minerals. They are used as such as they occur in nature without any processing (except drying) or chemical modification.  Sources of crude drugs They may be obtained from: 1- Plants (vegetative) sources, e.g., senna, digitalis, datura, cascara, cinchona, clove, etc. 2- Animal sources, e.g., honey, cod liver oil, Honeybee, bee wax, etc. 3- Marine sources, e.g., sponges, red algae, agar, etc. 4- Mineral sources, e.g., talc, kieselguhr, etc  Types of crude drugs The drugs can be classified according to which part of the plant is used as a drug, e.g., leaves, roots, stems, etc. The drugs obtained from the direct parts of the plants and containing cellular tissues are called as organized drugs, e.g., rhizomes, barks, leaves, fruits, entire plants, hairs, and fibers. Medicinal properties derived from plants can come from many different parts of the plant.  Types of crude drugs The drugs which are prepared from plants by some intermediate physical processes such as incision or extraction with a solvent and not containing any cellular plant tissues are called unorganized drugs. Aloe juice, opium latex, agar, gambir, gelatin, tragacanth, benzoin, honey, beeswax, lemon grass oil, etc., are examples of unorganized drugs.  Types of crude drug Organized drug Unorganized drug a) Juices b) Minerals Overground organs Underground organs c) Dried extract a) Herbs a) Roots d) Fixed oils b) Fruits b) Rhizomes c) Bark c) Bulbs d) Flower  Monograph A monograph is a paper on a single topic. An herbal monograph gives a basic description of the herb used for therapeutic purpose according to the pharmacopoeia. The following details are typically included in a crude drug's monograph: 1. Nomenclature include English, Arabic, Latin, French names. 2. Description and part used 3. Special condition for collection or preparation 4. Active constituents 5. Range of application and pharmaceutical products in market. 6. Dosage, use, and action of the herb. 7. Contraindications, side effects, incompatibilities with other medications. 8. Test of identity, adulteration, and allied drugs.  Pharmacopoeia Pharmacopoeia (G: pharmako-drug, poi-make, = drug-making) is a book containing directions for the identification of samples and the preparation of compound medicines and published by the authority of a government or a medical or pharmaceutical society (e.g., British pharmacopoeia, Indian pharmacopoeia, Japanese pharmacopoeia). Herbal pharmacopoeia intends to promote the responsible use of herbal medicines with the highest possible degree of efficacy and safety through the development of standards of identity, purity, and analysis for botanicals including the review of traditional and scientific data regarding their efficacy and safety.  Official Books It provide guidelines for the manufacture, quality control, packaging, storage, dose-regimen, indication, interaction etc. of different pharmaceutical product/medicine for treatment of the disease. Official books include: ▪ USP United States Pharmacopeia ▪ BP British Pharmacopoeia ▪ NF National Formulary ▪ BNF British National Formulary ▪ BDNF Bangladesh National Formulary ▪ BPC British Pharmaceutical Codex Official vs unofficial vs nonofficial drugs Official drugs: Any drug (crude or prepared) which is included in pharmacopeia or national formulary or recognized books and is officially used for therapeutic purpose. Unofficial drugs: A drug which has been recognized earlier included in pharmacopeia or national formulary or recognized books but not found in the current issue. Those substances were excluded from the recognized books due to their severe toxic effects on humans. Nonofficial drugs: A substance which possesses some medicinal properties and is unofficially used for therapeutic purposes but has never been included as a therapeutic item in pharmacopeia or any official drug literature of any country.  Classification of crude drugs 1) Alphabetical classification. 2) Taxonomical classification. 3) Morphological classification. 4) Chemical classification. 5) Pharmacological or therapeutic classification. 6) Chemo-taxonomical classification. Classification of crude drugs ❖ Alphabetical classification Crude drugs are arranged to the alphabetical order of their Latin or English names. ❖ Taxonomical classification In this system the drug are arranged according to taxonomical study of the plant which they obtained in phyla, orders, families, genera and species, etc. ❖ Morphological classification In this system, the crude drugs are grouped or arranged according to the plant or animal represented into organized (cellular) drugs and unorganized (acellular) drugs. Classification of crude drugs ❖ Chemical classification In this system, the crude drugs are divided into different groups according to the chemical nature of their most important constituents. ❖ Pharmacological classification In this system, drugs are grouped together according to therapeutic activity of their main chemical constituents. ❖ Chemo-taxonomical classification The availability of chemical constituents among different plant species/ families, form the basis of this classification.  Biological origin The natural or biological origin of the drug indicates the name of plant and family from which the drug is obtained. It is divided into two types: - Botanical origin (source) is used for the plants. - Zoological origin is used for animals. It includes the scientific name of the plant producing the drug, and it is very important to avoid any variation of the drug.  Biological origin Binomial system (Nomenclature): The binomial system was founded by the Swedish biologist Linnaeus. This system used for naming the plants till today. Bi = two, nomial = name, Each plant name have two Latin Parts. The first word denotes the Genus name and is written with the 1st letter in capital. The second word denotes the species name and written with the 1st letter in small.  Biological origin Binomial system (Nomenclature): The plant name is followed by names of persons (botanists) who, first described the species or varieties and usually represented by initial. Atropa belladonna L. (L. is,, the initial of the botanists Linnaus). Sometimes, the species name is derived from the author’s name, e.g., the species of Cinchona named after Charles Ledger who brought its seeds from Brazil in 1865 is known as Cinchona Ledergiana.  Nomenclature The species name is usually chosen to indicate certain characteristics of the plant or special meaning e.g.: 1- Character of the Plant: ❑ Hyoscyamus muticus (muticus=short), the plant is short. ❑ Barosma serratifolia, margin of the leaf is serrate. ❑ Atropa belladonna, (= beautiful lady, bella=beautiful, donna=lady). The juice of the berry placed in the eyes cause dilatation of the eye pupil. ❑ Glycrrrhiza glabra (glabra means smooth), refer to the fruit of this species which is a smooth pods. ❑ Conium maculatum (maculate = spotted), stem with reddish spotted patches.  Nomenclature 2- Character of the color: ▪ Piper nigrurn (= black; color of fruit is black). ▪ Nymphea alba (= white; color of flower). ▪ Digitalis purpurea (=purple; the color of flower). ▪ Digitalis lutea (=yellow; the color of flower). ▪ Brassica nigra (=black; the color of seed, Black mustard). ▪ Brassica alba (=white; the color of seed, white mustard).  Nomenclature 3- Character of aromatic plant: ❑ Myristica fragrans (fragrant= nice odour). ❑ Caryophyllus aromaticus (refers to aroma). 4- Geographical Source: ❑ Hydrastis canadensis (growing in Canada). ❑ Tamarindus indica (growing in India). ❑ Uriginia maritima (grows in coastal regions along the Mediterranean Sea). ❑ Cannabis indica (from India). ❑ Iris germanica (from Germany).  Nomenclature 5- Pharmaceutical (pharmacological) Activity or Active Constituents: ▪ Papaver somniferum (induce sleep, refers to the narcotic properties of the plant opium). ▪ Quillaia saponaria (contain saponins). ▪ Strychonus nux vomica (vomica means causing vomiting). ▪ Ipomoea purga (refers to purgative or laxative effect of plant). ▪ Brayera anthelmentica (refer expelling worms). 6- General meaning: ▪ Allium sativum (cultivated). ▪ Triticum vulgare (growing wild). ▪ Linum usitatissimum (most useful).  Nomenclature The genus name is usually chosen to indicate certain characteristics of the plant or special meaning e.g.: ❖ Glycrrrhiza glabra, Liquorice (Glycrrrhiza means gluco = sweet, riza = root, due to sweet taste of plant). ❖ Linum usitatissimum, Linseed (Linum means Linea =threads). ❖ Atropa belladonna (Atropa name of the Greek fate who cuts the threads of life, referring to the poisonous character of the plant).  Geographical origin The Habitat or geographical origin of the drug indicates the region in which the plant or animal yielding the drug grows. Plants growing in their native countries are said to be indigenous to these regions, e.g., Hyoscyamus muticus of Egypt, and Cannabis sativa of India (Indigenous Plants). Plants are said to be naturalized (acclimatized) when they grow in a foreign land or in a locality other than their native home (Naturalized OR Acclimatized Plants).  Geographical origin ✓ Example: - The active constituents are greatly affected by the region in which the plant grows e.g., Cannabis sativa, contains resin, cannabinol, when grown in India and other subtropical countries. However, when in grows in cold countries (Italy), it is freeing from the active constituents but grown for the production of fibers and seeds.  Commercial origin ✓ The commercial origin of a drug refers to plant production and the channels of trades or country or port of exportation or shipment of drugs. ✓ Example: - Canton rhubarb grow in China and shipped by way of Canton. - Alexandrian senna grow in Sudan but was shipped from Alexandria. - Spanish liquorice was produced and shipped from Spain.