Medicinal Plants Lecture 4 PDF (PG101 C, 2024)

Medicinal plants (PG101 C) Pharm D Clinical Program-Level I Heba El-Nashar, Ph.D. Lecture (4) Lecturer of Pharmacognosy...

Medicinal plants (PG101 C) Pharm D Clinical Program-Level I Heba El-Nashar, Ph.D. Lecture (4) Lecturer of Pharmacognosy Faculty of pharmacy Ain Shams University 2024 Course Syllabus No. Lecture Professor Introduction to medicinal plants and pharmacognosy Brief historical overview. 1 Natural products: definition, origin, classification. Taxonomical classification & nomenclature. 2 Natural products and their biological activity. Dr. Heba El-Nashar Propagation of Medicinal plants 3 Plant cell and tissue culture. Factors affecting plant growth & cultivation. Production of crude drugs. 4 Adulteration of medicinal plants. Assoc. Prof. Nehal Sabry 5 Leaves: introduction, medicinal leaves. 6 Midterm Exams 7 Examples of medicinal leaves. Assoc. Prof. Nehal Sabry 8 Flowers: introduction, Examples of medicinal flowers. 9 Examples of medicinal flowers. 10 Bark introduction, Examples of medicinal barks. Prof. Dr. Rola Milad 11 Examples of medicinal barks. 12 Herb: introduction, Examples of medicinal herbs. Assoc. Prof. Iriny Ayoub Lecture 4 ❑ Production of Crude drugs ❑ Adulteration of Medicinal Plants ❑ Detection of Adulterant Identity PRODUCTION OF CRUDE DRUGS  Production Process Cleaning & Garbling Curing Collection Preparation Drying Packing Storage I-Collection To ensure maximum quality, crude drugs should be collected at: ▪ The appropriate season (Ex: Rhubarb....no Anthraquinones in winter) ▪ Particular stage of development or age (Ex: Some fruits must be collected unripe) Factors Affecting Drug Collection 1.Time of the year (Seasons) 2.Time of the Day 3.Stage of maturity and age Factors Affecting Drug Collection (Cont’) 1. Time of the year (Seasons) Plant constituents vary in amount and nature throughout the year Medicinal Plant Season Constituent Rhubarb Winter Anthranols Summer Anthraquinones Colchicum Autumn Starch, no colchicine Spring Colchicine (Bitter taste) Hyosyamus Winter ↓alkaloids Summer ↑alkaloids Factors Affecting Drug Collection (Cont’) 2. Time of the day Plant constituents vary in amounts according the collection time of the day Medicinal Plant Collection Time Constituent % Digitalis Leaves Afternoon ↑cardiac glycosides Morning ↓cardiac glycosides Solanaceous Leaves Afternoon ↓Alkaloids Morning ↑Alkaloids Factors Affecting Drug Collection (Cont’) 3. Stage of Maturity and Age Plant constituents vary in amounts according the stage of maturity and age Medicinal Plant Stage of Maturity Constituent % Santonica Flower Unexpanded Flower ↑ Santonin Expanded Flower ↓Santonin Solanaceous Leaves Flowering Stage ↑Alkaloids II-Preparation of Crude Drugs 1. Cleaning 2. Garbling 3. Drying 4. Curing 5. Packing 6. Storage and Protection II-Preparation of Crude Drugs 1- Cleaning and 2-Garbling ▪ Underground organs should be freed from dirt and soil by brushing or washing under water. ▪ Sometimes, rootlets are cutoff, and stalks are removed from leaves and fruit. ▪ Garbling is a process of removing extraneous matter such as sand and unofficial parts of plant. II-Preparation of Crude Drugs 3-Drying ▪ Fresh organs usually contain a high % of moisture. ▪ By drying, the plant loses most of this moisture and hence a great % of its weight. ▪ The Aims of Drying: A. Prevents the action of mould and bacteria B. Fixation of constituents which may be altered by the action of enzymes C. Facilitates grinding D. Renders the drug more convenient for commercial handling e.g. packing, storage and transport II-Preparation of Crude Drugs 3-Drying Methods of Drying** Natural Drying Artificial Drying Air drying may be done in the It immediately stops sun for items which are not enzymatic action More affected by direct sunlight rapid than natural drying May be done in shade Suitable for countries where weather conditions is not suitable for natural drying II-Preparation of Crude Drugs 3-Drying Drying Chambers ▪ This is a controlled process. It consists of a closed space with several movable screen trays which are arranged to allow free circulation of heated air. The source of heat usually enters through the bottom. ▪ Leaves, herbs and flowers are dried at temperatures (20-40°C) lower than that required by barks and roots (30-65°C) II-Preparation of Crude Drugs 4-Curing** This is a process of fermentation or hydrolysis applied to drugs before drying to accomplish certain changes in active constituents. Example: Freshly collected vanilla pods contain glucovanillin which are converted to vanillin through curing (hydrolysis and oxidation) Curing Glucovanillin Vanillin II-Preparation of Crude Drugs 5-Packing of the drugs ▪ Packing may be loose or under pressure. ▪ If drugs are transported, packing must provide protection as well as economy of space. ▪ Drugs that are prone to deterioration need moisture-proof packing. II-Preparation of Crude Drugs 6-Storage ▪ Storage is the last step of crude drug preparation before being used. ▪ It is a critical step since drugs usually deteriorate along the time of storage. ▪ The changes that take place during storage are mostly objectionable as the rancidity of fatty drugs and resinification of volatile oils.  Factors Affecting Deterioration of Drugs During Storage**: 1) Physicochemical Factors 2) Biological Factors A. Moisture A. Bacteria B. Light B. Moulds C. Temperature C. Insects D. Oxygen D. Rodents Factors Affecting Deterioration of Drugs During Storage: 1) Physicochemical Factors: A. Moisture It causes activation of enzymes that change the active constituents and promote the growth of microbes. This problem may be avoided by temporary inactivation of enzymes by keeping the drug under dry conditions or using a dehydrating agent or permanently by destroying the enzyme with alcohol. B. Light It affects drugs with marked colors Ex: Yellow Rhubarb changes to red, or the fading of petal colors. Drugs should be stored in opaque or amber colored glass containers C. Temperature High temperature activates enzymes causing decomposition of active principles such as volatile oil. D. Oxygen Oxidation of constituents resulting in rancidity of fixed oils and resinification of volatile oils. Factors Affecting Deterioration of Drugs During Storage: 2) Biological Factors: A.Bacteria: Affects cotton fibres and starchy drugs B.Moulds: Produces a mass of clinging particles in powdered drugs C.Insects: Infect sugar containing drugs render the drugs powdery and porous D.Rodents: Leave their remains causing drug spoilage. Drugs should be stored in moisture-proof, air-tight, light-proof containers at low temperatures. Adulteration of Medicinal Plants  Adulteration Adulteration To make impure or inferior by adding foreign substances to something OR by replacing it. Adulterant The added substances used for adulteration. This usually happens to rare or high-priced drugs. An adulterated drug does not comply with the official requirements of the Pharmacopoeias Types of Adulteration 1.Sophistication 2.Substitution 3.Admixture 4.Deterioration 5.Spoilage 6.Inferiority  1.Sophistication The addition of inferior material to any drug with intend to defraud Examples: ▪ Adulteration of ginger with wheat flour, Capsicum for pungency and curcuma for color ▪ Adulteration of beeswax with yellow colored paraffin wax 2. Substitution The complete replacement of the genuine drug with a different article A.Substitution with an Inferior Commercial Variety Ex: Arabian Senna and Dog Senna to replace genuine Senna Ex: Capsicum minimum and chilies to replace Capsicum annum B.Substitution with Exhausted Drugs Ex:Using exhausted Umbelliferous fruit or Clove flowers which retain their appearance after exhaustion. C. Substitution by Superficially similar but cheaper natural drugs that may have no relation to genuine drug Ex: Peach and Apricot kernels for almonds Ex: Leaves of Scopolia for Belladonna  Substitution of Senna Pods DOG SENNA Genuine SENNA Substitution of Exhausted Drugs Caraway Cumin Fennel Anise Umbelliferous Fruits Peach and Apricot kernels Almonds kernels 3.Admixture ▪ This is the addition of one article to another by accident or through ignorance and carelessness. ▪ May occur by adding other unwanted parts of the same plant as stems, stalk and soil. or collection of other plants by mistake and ignorance of collection Ex: Argel instead of Senna leaves Argel Senna  4.Deterioration ▪ The imperfect quality of the drug due to destruction or removal of valuable active constituents through extraction, distillation, ageing, heating , storage, insects or other undesirable conditions. Ex: Whole cloves from which the oil has been removed Ground linseed from which oil has been expressed 5.Spoilage This is a form of deterioration in which the quality of the drug is impaired or destroyed by the action of fungi and bacteria. Ex: Mouldy coffee and wormy Rhubarb 6.Inferiority ▪ Drugs of sub-standard condition as a low percentage of active constituents ▪ Examples: Nux Vomica seeds ( low % of Strychnine) Detection of Adulteration Identity Detection of Adulterant Identity 1. Inspection of morphology 2. Histology and Microscopic Examination 3. Microscopic Linear Measurements 4. Quantitative Microscopy 5. Solubility and Physical Constants 6. Qualitative Chemical Tests 7. UltraViolet Light 8. Assay Detection of Adulterant Identity 1.Inspection of morphology Ex: Indian Senna Pods Substituted for Alexandrian Pods Conium for Anise Detection of Adulterant Identity 2.Histology and Microscopic Examination ▪ Using various measurements as Vein Islet Number and Palisade Ratio for leaf drugs e.g. Belladonna and Senna ▪ Inspection of type of trichomes and stomata or Stomatal Index. Detection of Adulterant Identity 3.Microscopic Linear Measurements The diameter of starch granules as well as the diameter of Phloem fibers will assist to differentiate between Cassia and Cinnamon barks Detection of Adulterant Identity 4.Quantitative Microscopy This includes counting the number of starch grains or sclerieds or epidermal cells per certain area of leaf. The results are constants for each drug and are used to detect adulterants Detection of Adulterant Identity 5.Solubility and Physical Constants ▪ The property of solubility in different organic solvents aids in the examination of many oils and oleo-resins. ▪ Many physical constants include: o Specific gravity o Optical Rotation o Viscosity o Refractive Index Detection of Adulterant Identity 6. Qualitative Chemical Tests ▪ Many color tests are specific for certain substances. ▪ Ex: Ammi visnaga will give Rose Red color with KOH while Ammi majus will not. Ammi visnaga Ammi majus Detection of Adulterant Identity 7. UV light ▪ For identification of Chinese Rhubarb which may be used to adulterate Indian Rhubarb. Chinese Rhubarb Indian Rhubarb  Detection of Adulterant Identity 8. Assays ▪ Assays are conducted to determine active constituents e.g. o Alkaloidal assay of belladonna o Volatile oil content ▪ The results obtained will detect whether the drugs are exhausted and inferior quality Questions Which of the followings is defined as imperfect quality of the drug due to destruction or removal of valuable active constituents through extraction, distillation: A. Deterioration B. Spoilage C. Inferiority D. Admixture E. Substitution  Questions Which of the following terms represents adulteration of ginger with wheat flour : A. Deterioration B. Sophistication C. Inferiority D. Admixture E. Substitution Questions Which of the following terms represents adulteration of ginger with wheat flour: A. Deterioration B. Sophistication C. Inferiority D. Admixture E. Substitution  Questions Which of the following terms represents adulteration of ginger with wheat flour: A. Deterioration B. Sophistication C. Inferiority D. Admixture E. Substitution Questions Which of the following processes is essential for preparation of vanillin: A. Cleaning B. Drying C. Curing D. Packing E. Garbling  Questions A. Illustrate the factors affecting Drug collection. B. Illustrate the detection methods of adulteration. C. Enumerate different types of adulteration D. Mention the essential steps of herbal drug preparation E. Enumerate factors affecting drug deterioration during storage Finally, I would like to thank you for your attendance, and I Wish bright and colourful days in our blue building, making happy memories and great success…. Love you all Heba El-Nashar