Pharmacognosy 2 (PG 303): Herbs Intro. and Lobelia (2023/2024) - PDF

# Pharm D Program (2023/2024) ## Pharmacognosy 2 (PG 303) ### Lecture No. (7) ### Herbs Intro. and Lobelia #### By #### Dr. Mostafa Mahmoud Hegazy PH.D #### Associate Professor of Pharmacognosy #### 7 January 2025 #### www.su.edu.eg ## Lecture's - Kinds of Herbs according to life duration - Shapes...

# Pharm D Program (2023/2024) ## Pharmacognosy 2 (PG 303) ### Lecture No. (7) ### Herbs Intro. and Lobelia #### By #### Dr. Mostafa Mahmoud Hegazy PH.D #### Associate Professor of Pharmacognosy #### 7 January 2025 #### www.su.edu.eg ## Lecture's - Kinds of Herbs according to life duration - Shapes of the Stem - Kinds of stems - Microscopical Characters - Alkaloids containing herb (Lobelia) - **The Herb:** Tender parts of the plant axis ex. Leaves, flowers and fruits. Also includes the whole plant. - **The Herb** - Flower - Leaves - Fruit - Seeds - Stem (Bark) - Roots & rhizomes (Undergroud organs) ## Kinds of Herbs according to life duration - **Biennial (Bicarpic):** lives for two seasons but not for more than two years. Reserve food present. e.g. Digitalis and Sugar beet. - **Annual (monocarpic):** lives for one season or one year and dies. No reserve food e.g. Umbelliferae. - **Perennial (polycarpic):** lives for more than two years or indefinitely. e.g. Belladonna. ## Pharm D Program (2023/2024) ### The Stem - Part of the plant which carries the leaves and other plant organs. - It has nodes and internodes. ## Shapes of the Stem - Cylindrical - Ribbed or wh furrows - Triangular - Tetragonal or Quadrangular - Flattened - Winged ## Kinds of stems Classified acc. to the nature and texture stems: 1- **Herbaceous stem:** Green coloured, soft in texture, readily broken, covered with hairs and it dies at the season end (lack or very little cambium). 2- **Succlent stem:** Thick and fleshy (storage of water). 3- **Woody:** When the stem is hardy due to large xylary elements and cork. 4- **Suffruticose:** When the stem is small in size, woody at the base and herbaceous above. e.g. Thyme 5- **Fruticose or Shrubby:** stem is woody larger than suffrutiose and freely branching near the ground. (i.e. the plant being a shrub). ex. Lichen, “thallophytic plant like”. 6- **Culm:** large nodes and hollow internodes e.g. Gramineae. 7- **Creeping stem:** a prostrate ساجد branch at the ground level giving new plant. Creeping stems with short internodes (**runners**) e.g. Strawberry long thick internodes (**stolons**) e.g. licorice 8- **Sucker:** Like runner but the branches arise and grow below the ground e.g. Mentha, Rose. 9- **Climbing:** weak stem and attaches to a support by tendrils, hooks or by adventitious roots... e.g. Pepper, Hops. 10- **Twining:** When the stem attaches itself to a support by winding around it as in Convolvulus. ## Microscopical Characters T.S. in Young (herbaceous) stem of Dicotyledons [Vascular bundle is Open ] - **1- Epidermis:** with cuticle, stomata and hairs - **2-Cortex:** Parenchyma, Collenchyma and endodermis: inner most layer of cortex - **3- Pericycle:** parenchyma, collenchyma, fibers, clereids. - **4- Vascular bundles:** Cambium: Responsible for 2ry thickening giving 2ry phloem outside and 2ry xylem inside. Phloem Xylem: Vessels (Spiral, annular, pitted. Fibers and wood parenchyma) - **5- Pith:** parenchyma. ## Medicinal herbs - **Official Herbs** - Lobelia - Peppermint - Thyme - Solanaceous - Stramonium - Egyptian Henbane - Belladonna - **Unofficial Herbs** - Cannabis- Indian Hemp - Catharanthus - Ephedra - Cymbopogon - Lemon Grass - Broom Tops - Savin Tops - **Thallophyta (lower plants)** - **I- Algae** - Fucus - Laminaria - Carragen - **II- Fungi.** - Ergot - Yeast - Penicillium - Mushroom - Mycotoxins - **III- Lichenes.** - Iceland Moss ## Herbs chemotaxonomy - **Herbs Containing Alkaloids** - Lobelia - Solanaceous Herbs - Stramonium - Egyptian Henbane - Belladonna - Catharanthus (Vinca) - Ephedra - Broom Tops - **Herbs Containing Volatile oil** - Peppermint - Thyme - Cymbopogon (Half Bar) - Lemon Grass - Savin Tops - **Herbs Containing Resins** - Cannabis- Indian Hemp ## Pharm D Program (2023/2024) ### Herbs Containing Alkaloids ## Pharm D Program (2023/2024) ### Lobelia Herb عشب اللوبيليا ### Indian Tobacco الدخان الهندي #### Origin: The dried aerial parts of Lobelia inflata Linne Fam. Campanulaceae, collected at the end of the flowering stage. ## Pharm D Program (2023/2024) - It is used by North American Indians as domestic medicine as a cigarette for asthma. ## Pharm D Program (2023/2024) ### Macroscopical characters - **Herb:** - Annual herb, 40-60 cm. - **Odour:** slight irritant. - **Taste:** at first slight but subsequently burning and acrid. - **Stem** - **Color:** Green to yellowish; usually large purplish patches. - **Shape:** Angular, irregularly furrowed with narrow wings. - **Touch:** Hairy on the upper parts, glabrous on the lower. ## Pharm D Program (2023/2024) - **Leaves** - Alternate green, with scattered stiff hairs especially the margin and veins. - Lower leaves, oblong, petiolate. - Upper leaves smaller, oval to lanceolate, sessile. ## Pharm D Program (2023/2024) - **Flowers:** - Short pedicel, arranged in long racemes. - Calyx tubular pale blue with 5 linear teeth - corolla, tubular, bilabiate. - Stamens, with blue anthers united above, forming a curved tube enclosing the bifid stigma. - Ovary is inferior, bilocular, bicarpellary ## Pharm D Program (2023/2024) - **Fruit:** - Inflated capsule, dehiscing by 2 pores at the summit, ovoid, light brown, inferior, crowned by the remains of the calyx, with 10-ribbed membranous pericarp. - Internally, it's bilocular containing numerous seeds arranged on axile placenta. - **Seeds:** - Minute, oval oblong, reddish-brown, with fine reticulations. ## Pharm D Program (2023/2024) - **Lobelia inflata Stem T.S.** - **Lobelia inflata leaf T.S.** ## Pharm D Program (2023/2024) ### Physical characters of the powder: - **Color:** green to dark green - **Odor:** slight irritant - **Taste:** at first slight but subsequently burning and acrid. ## Pharm D Program (2023/2024) ### Powdered Lobelia - **Stiff hair** - Long, non-glandular hair (conical, unicellular and covered with warty cuticle) - **Laticiferous vessels** - Isolated by caustic potash - **Seed coat brown,** - Thick walled lignified epidermal cells ## Pharm D Program (2023/2024) - **Woody fibres** - **Xylem vessels** - **Fragments of stem and leaves showing beaded papillosed epidermal cells, anomocytic stomata and hairs.** ## Pharm D Program (2023/2024) ### Active Constituents: - 1- 0.3-0.4% alkaloids, mainly lobeline, lobelanine, lobelanidine and isolobelanidine. - 2- a colourless Crystalline neutral principals (inflatin) and lobelic acid. - 3- Not acrid but Pungent volatile oil and resin. ## Pharm D Program (2023/2024) ### Chemical test: - Extract with acidulated water----- filter---- add few drops of Mayer's reagent -------- a whitish turbidity. ## Pharm D Program (2023/2024) ### Uses - 1- Lobelia has a nicotine like action, so its used in breaking of smoking habi - 2- Lobeline relaxes the bronchial muscle end thus dilates the bronchioles. It is given in spasmodic asthma and in the dysnea of chronic bronchitis - 3- as expectorant and in treatment of cough - 4- In large doses it produces vomiting and may cause collapse through medullary paralysis. ## Pharm D Program (2023/2024) ### Contraindications: - Lobelia alkaloids are excreted in milk should not be administered by pregnant or nursing mothers.