Pharmacognosy II - Fall 2024/2025 Lecture Notes (PDF)

Course Title: Pharmacognosy II Course Code: PHG 213 Week number: 13 Lecture number: 11 Lecturer: Dr. Hanan Samir Marzouk Fall 2024 / 2025 Unorganized Drugs Part II  Lecture Objectives 1. What are Latex, Juices, Extracts and gums? 2. How are they formed? 3. What are physic...

Course Title: Pharmacognosy II Course Code: PHG 213 Week number: 13 Lecture number: 11 Lecturer: Dr. Hanan Samir Marzouk Fall 2024 / 2025 Unorganized Drugs Part II  Lecture Objectives 1. What are Latex, Juices, Extracts and gums? 2. How are they formed? 3. What are physical characters and chemical composition of each class? 4.What are Opium, Aloe, Agar, Gelatin, Gum acacia and gum tragacanth?  Unorganized Drugs Gums Dried Extracts e.g. Acacia Dried Juices e.g. Agar & Tragacanth Gelatin Dried Latex e.g. Aloe e.g. Opium Resins Resins e.g. Colophony, Mastic Oleoresins e.g. Male Fern, Turpentine, Copaiba Oleogumresins e.g. Asafoetida, Myrrh Glycoresins e.g. Jalap resins and Podophyllum resins Balsams e.g. Benzoin, Balsam Peru, Balsam Tolu II- Dried Latex  What’s Latex? Definition: Latex is an emulsion or suspension, the continuous phase of which is an aqueous solution of mineral salts, proteins, sugars, tannins, alkaloids, etc., and the suspended particles are oil droplets, resin, gum, protein or starch.  Properties Latex is often white in color, as in opium (Papaver somniferum), may be yellow as in Argemone mexicana or red as in the rhizome of Sanguinaria canadensis. Latex occurs in the plant in special structures named laticiferous cells, tubes or vessels, from which it is obtained by incision of the plant.  Opium ‫األفيون‬ Plant source: Opium is the air dried latex obtained by incision from the fully grown but unripe capsule of Papaver somniferum family Papaveraceae. Collection & Preparation Turkish Indian Macedonian  Shape: more or less rounded or cubical pieces or some what Description flattened or brick – shaped masses. 8-10cm in diameter. Commonly weighing between 250-1000gm. Sometimes wrapped in tissue paper, cellophane or covered with poppy leaves. Externally dark brown to chocolate brown. More or less elastic when fresh, becoming hard and tough, or occasionally brittle on keeping. Opium has strong charaeteristic narcotic odour and characteristic very bitter taste.  Constituents Opium contains about 30 different alkaloids, (belonging to different chemical groups) which occur in combination with MECONIC acid, of which about 5% is present, and with sulphuric acid. The most important alkaloids are: 1. Morphine (10-20%), 2. Codeine (methyl morphine 0.3-0.4%), 3. Narcotine (2-8%), 4. Thebaine (0.2-0.5%) 5. Narceine 6. The remaining alkaloids are present in very small quantities constituting together rather more than 1% of the drug.  Test for Identity (Test for Meconic Acid) Warm about 20-30mg of powdered opium in 2-3 ml of water for few minutes and then filter. On adding a few drops of 5% ferric chloride solution to the filtrate, a purplish red color is produced and the color is not destroyed by the addition of dilute hydrochloric acid or 5% mercuric chloride solution  Uses Opium is used as: 1. Hypnotic and sedative. 2. To relieve pain and calm excitement. 3. An astringent in diarrhea and dysentery. 4. Sedative in certain forms of cough. Its action is due to the morphine content. N.B. All the important alkaloids have narcotic action III- Dried Juices  Aloes ‫الصبر‬ Aloes is the solid residue obtained by evaporating the juice which drains from the cut leaves of Aloe ferox and its hybrids known in commerce as Cape Aloes or of Aloe vera, known in commerce as Curacao Aloes, or of Aloe Perryi, known in commerce as Socotrine or Zanzibar Aloes, Family Liliaceae. Preparation  Description Cape aloe occurs in dark-brown or greenish-brown glassy masses. Thin fragments have a deep olive color and are semi- trans parent. The powder is greenish-yellow. has a very characteristic odour while the taste is very bitter and nauseous.  Constituents Cape Aloe Curacao Aloe Socotrine or Zanzibar Aloe Anthraquinone glycoside known as barbaloin (C- glycoside) [Pale yellow crystalline substance] + β- barbaloin + Isobarbaloin - which is the crystalline and amorphous isomeric with isomer of baraloin. barbaloin.  Test for Identity Boil about 0.5 gm of powdered Aloe with 50 ml water for 2-3 min. filter. The filtrate responds to the following tests: Borax test: To 10ml of the filtrate add 0.25 gm of borax and dissolve by heat; pour some of the dark fluid into water where a green fluorescence is produced. All kinds of Aloes respond to this test.  To Differentiate between different types of Aloes Cupraloin test (for isobarbaloin): dilute 2 ml of the filtrate to 10 ml with water, add about 0.5 ml of sodium chloride and then about 1 ml of alcohol and warm. Deep wine red colour Pale wine red No colour quickly fading Cape Aloe Socotrine or Zanzibar Aloe Curacao Aloe  Uses All varieties of Aloes have more or less powerful purgative action. Aloe is one of the most valuable purgatives in certain forms of constipation as it improves the digestion and does not lose its activity by repetition. Externally, Aloe is used in cream forms for diabetic ulcers and to promote hair growth.  IV- Extracts Includes drugs prepared by evaporating aqueous decoction of parts of certain plants or animals.  1- Gelatin ‫الجيالتين‬ Origin: Gelatin is the protein obtained by boiling the collagenous tissue of animals such as skin, tendons, ligaments and bones with water and evaporating the aqueous extracts and drying the residue in air. Derived from various domestic animals, such as Ox (Bos Taurus), the sheep (Ovis aries), family Bovidae Constituents: Gelatin consists of the protein glutin. Uses: 1. Used as nutrient. 2. It is also used as a basis for glycerin suppositories 3. For the preparation of pastilles 4. For the preparation of nutrient media for the growth of bacteria.  Chemical test 1. By heating powder gelatin with soda lime, ammonia is evolved, showing the presence of nitrogen. 2. Solution of gelatin in water: a) + Tannic acid → Buff precipitate b) + Picric acid → Heavy yellow precipitate c) + Few drops of CuSO4 solution & xss 20% NaOH → Violet colour [Biurette test]  2- Agar-Agar ‫آجار‬-‫آجار‬ Origin: Agar is the dried mucilaginous substance prepared from Gelidium corneum, G. cartilageneum family Gelidiaceae. and other closely related red algae. Constituents: Agar is heterogenous polysaccharide contains two principles which are agarose and agaropectin. Uses: 1. Used in the treatment of constipation [Agar passes through the intestinal canal unchanged, but absorbs water during its passage and thus promotes peristalsis]. 2. As emulsifying agent. V- Gums  General Characters 1. Gums are amorphous, translucent solids. 2. Insoluble in alcohol and most organic solvents; but soluble in water to yield viscous, adhesive solutions, or are swollen by the absorption of water into a jelly- like mass. 3. They consists of calcium, potassium and magnesium salts of complex substances known as polyuronides, and can be hydrolyzed by prolonged boiling with dilute acids when they yield mixtures of sugars and organic acids. 4. Gums are produced pathologically by the conversion of the cell-walls of the tissue into gums, probably by means of enzymes, the process which is termed Gummosis. 5. Gums are abnormal products , resulting from pathological conditions brought about either by injury or by unfavorable conditions of growth.  Mucilage Mucilage are similar in constitution to gums, but are normal products of cell activity, being secreted in the cell and laid down like hemicelluloses. Artificial gum (Dextrin) Is produced from starch, differs originally from gums in being entirely converted into dextrose (glucose) by dilute mineral acids, it is strongly dextrorotatory while natural gums being slightly laevorotatory.  Gums Gum Acacia Gum Tragacanth ‫الصمغ العربي‬ ‫ صمغ كثيراء‬/ ‫صمغ كثيرة‬ Is the dried Gummy Is the dried gummy exudation from the stems exudation from stem of and branches of Acacia Astragalus gummifer, Senegal or of some other Family Fabaceae species of Acacia, (Leguminosae), and other Family Fabaceae Asiatic species of (Leguminosae). Astragalus.  Constituents Gum Acacia Gum Tragacanth ‫الصمغ العربي‬ ‫ صمغ كثيراء‬/ ‫صمغ كثيرة‬ Gum Arabic consists * Tragacanth consist of two almost entirely of parts: 1. Tragacanthin (water glycosidal acid named soluble) Arabic acid, combined 2. Basorin (water insol). with potassium, * Tragacanth contains also magnesium and calcium. traces of starch, cellulose and nitrogenous It also contains diastase substances. and an oxidase enzyme * No oxidase enzyme is present.  Test for Identity Gum Acacia Gum Tragacanth ‫الصمغ العربي‬ ‫ صمغ كثيراء‬/ ‫صمغ كثيرة‬ Dissolve about 0.25 gm of the Place a little powdered gum coarsely powdered drug in 5 tragacanth on a porcelain tile, ml of distilled water by add few drops of N/50 iodine shaking in the cold. Add 0.5 solution and rub to form a ml of hydrogen peroxide and smooth paste. It acquires an 0.5 ml of benzidine solution, olive green color (due to the shake and allow to stand for presence of starch). few minutes; a deep blue color or greenish blue color is formed due to the presence of oxidase enzyme  Uses Gum Acacia Gum Tragacanth ‫الصمغ العربي‬ ‫ صمغ كثيراء‬/ ‫صمغ كثيرة‬ Used as: Used as: 1. Demulcent 1. Suspending agent for 2. Suspending and insoluble powders. emulsifying agent for 2. Binding agent in pills oils. and tablets.