Rhizome 1 PDF

Subterranean stems DR MAI AB DEL HADI m ai. ab de l hadi@ ph arm.aun.e du.e g 1. Rhizomes (e.g. ginger) horizontal underground stems with nodes, internodes, dry scale leaves, and adventitious roots. 2. Tubers (e.g. white potatoes) fleshy underground stems (swollen ends of rhizome) mo...

Subterranean stems DR MAI AB DEL HADI m ai. ab de l hadi@ ph arm.aun.e du.e g 1. Rhizomes (e.g. ginger) horizontal underground stems with nodes, internodes, dry scale leaves, and adventitious roots. 2. Tubers (e.g. white potatoes) fleshy underground stems (swollen ends of rhizome) modified to store starch. 3. Bulbs (e.g. onion): underground buds with the stem reduced to a small disc on which fleshy storage leaves are clustered. 4. Corms (e.g. colchicum) upright underground fleshy stems covered by leaves reduced to dry covering scales (short internodes).  Subterranean stems Stem- Rhizomes Corms Bulbs Sucker tubers  Subterranean stems Rhizomes Rhubarb Ginger Galangal Curcuma Corms Bulbs Hydrastis Colchicum Garlic Filix-mas Valerian Hellebore Podophyllum  Subterranean stem Characters Root (Rhizomes) Nodes and internodes present absent Scale leaves and present at nodes absent axillary buds Wrinkles mainly transverse mainly longitudinal Scars of fallen roots of rootlets No pith present in the solid central mass of xylem Pith centre except in few cases as monocots e.g. Sarsaparilla 90% no pericycle as cork is formed wide primary cortex in this region during secondary Primary cortex and pericycle thickening Only 2ry cortex is present Secondary cortex present present Some Zingiberaceous rhizomes 1- Ginger 2- Galangal 3- Turmeric (Curcuma) ‫‪Ginger‬‬ ‫الزنجبيل‬  Ginger It is the scraped or unscraped rhizomes of Zingiber officinale F. Zingiberaceae Propagation of the plant is carried out by dividing it into small pieces called fingers. Each piece contains a bud. Sympodial branching pieces (hands or races) finger  Types of commercial ginger Coated or unscraped ginger ( no or little cork is removed) Scraped or uncoated ginger ( completely peeled) Limed ginger: treated with calcium sulphate or carbonate…….. Whitish appearance Bleached ginger: treated with sulphurous acid or chlorine  Microscopical characters Ovoid or sac-shaped starch granules showing eccentric hilum and faint striation In the cortex, numerous oleo-resin cells with bright yellow content. Dentate fibres with very thin transverse septa and numerous pits. Large reticulately thickened xylem vessels.  Active constituents 1-2% volatile oil , mainly composed of Monoterpenes i.e. camphene, citral and borneol Sesquiterpenes i.e. zingibrene Sesquiterpene alcohols i.e. zingiberol Resinous matter Starch and mucilage  Gingerols (pungent phenolic compounds, primary bioactive compounds) e.g. 6-, 8-, and 10- gingerol. Pungency can be destroyed by boiling with 2% KOH soln. Shagaols (the degradation products of gingerols) Aliphatic hydroxyl group β to the carbonyl group Elimination of the hydroxyl group to form a double bond α to the carbonyl group Ginger has: Antioxidant activity Anti-inflammatory Antiulcer activity Circulatory stimulant Antibacterial, antifungal and antiviral activities Reduces the total plasma cholesterol Anticancer activity Uses Antiemetic, used in multiple types of nausea especially the pregnancy-induced and postoperative nausea and vomiting. But it is less successful to control chemotherapy-induced nausea and vomiting  Anti-ulcer helps in osteoarthritis by reducing inflammation and pain. It also protects from gastric side effects of painkillers prescribed in arthritis. Condiment and carminative Ginger acts peripherally, within the gastrointestinal tract, by increasing the gastric tone and motility due to anticholinergic action. It increases gastric emptying. This combination of functions explains the ability of ginger to relieve symptoms of functional gastrointestinal disorders, such as dyspepsia, abdominal pain, and nausea, which is often associated with decreased gastric motility.  Gini-Cap Digestant and antiflatulance drugs In osteo-arthritis and cartilage degradation Natural massage analgesic ‫‪Galangal‬‬ ‫الخولنجان‬  Galangal (lesser galangal) Obtained from the lesser galangal Alpinia officinarum, F. Zingiberaceae A.C. Volatile oil consists of cineole and methyl cinnamate, galangol (tasteless yellow cyrstalline substance) Diarylheptanoids from lesser galangal have antioxidant, anti- inflammatory, antiemetic, and anticancer activities. Uses: spice, stimulant, carminative Turmeric ‫الكركم‬  Turmeric The prepared rhizomes of Curcuma domestica F. Zingiberaceae Active constituents The essential oil is composed of: -Sesquiterpenoids e.g. Ar-turmerone, α-turmerone and β- turmerone (ketonic in nature, 40%). Turmeronol A and turmeronol B (phenolic sesquiterpenes). -Curcuminoids (colouring matter) from the diarylheptanoid class, the major three are curcumin, demethoxycurcumin and bisdemethoxycurcumin. -Resin and gelatinized starch  Curcumin Curcumin inhibits cell proliferation, invasion, metastasis, and angiogenesis of different cancers. Pharmacological activities Antioxidant, antimicrobial, anticarcinogenic, and anti- inflammatory activities. Uses Jaundice and hepatitis treatment due to antihepatotoxic action of curcuminoids Aromatic stomachic, diuretic, Choleretic Colouring agent, condiment, in preparation of sauces Paper impregnated with alcoholic extract of turmeric is used as a test for boric acid and borates Rhubarb ‫الراوند‬  Rhubarb It is the peeled and dried rhizomes and big roots of Rheum palmatum and Rheum officinale except Rheum rhaponticum F. Polygonaceae. English rhubarb: R. officinale and R. rhaponticum Chinese rhubarb: R. palmatum Leaves can be poisonous, if consumed in a high dosage due to the high amount of oxalic acid which is a nephrotoxic and corrosive acid, while petioles (leaf stalks) are rich in vitamin C, dietary fibres (74%) and calcium (oxalate form). The rhizomes are decorticated (peeled) and cut either longitudinally (flats) or transversely (rounds), then dried. Surface: clear reticulations, reddish brown points (star spots).  Star spot An abnormal structure arises at the periphery of the pith. It is a result of development of several concentric bundles having phloem towards the centre and xylem externally. Medullary rays are radiating slightly curved, with dark yellow content which gives rose-red colour with ammonia solution.  Microscopical characters Starch: simple Large calcium oxalate (rounded) or clusters compound (2-5 components) muller shape with radiate or split hilum  Reticulated non-lignified No cork, no X.V.s sclerenchymatous fibres or cells because of deep peeling of the drug during its preparation. N.B. Absence of scl. and Abundant parenchyma supporting tissues in large cells (m.r. and ground rhizomes because the tissue) filled with starch ground is fulfilling this need. granules and Ca oxalate cluster crystals.  Active constituents Anthraquinones AQ without carboxyl groups e.g. chrysophanol, aloe-emodin, emodin and physcion AQ with carboxyl groups e.g. rhein and its glycoside gluco-rhein Anthrone or homo-dianthrone e.g. of chrysophanol or emodin or aloe-emodin or physcion. Hetero-dianthrones e.g. palmidin A  emodin rhein aloe-emodin chrysophanol emodin dianthrone palmidin A Astringent compounds Gallic acid Glucogallin Epicatechin gallate Catechin  Chemical test Borntrager’s test (anthraquinone glycosides) Modified Borntrager’s test (C-glycosides) Rheum rhaponticum (False Rhubarb) The extract has been marketed as a non-hormonal alternative for women managing menopausal symptoms. Experimental studies had demonstrated that both the extract and its individual constituents—rhaponticin and desoxyrhaponticin, with small amounts of aglycones rhapontigenin and desoxyrhapontigenin—have exhibited selective estrogen receptor (ER)-β agonistic activity. Test for rhapontic rhubarb (non-official rhubarb): Macerate about 0.5 g of powder with alcohol for 20 min, Filter and place one drop on a filter paper and examine it in the ultraviolet light, the spot shows velvety brown colour in case of official rhubarbs but rhapontic rhubarb shows blue fluorescence. Uses Laxative or purgative used in acute constipation and in case of anal fissure and/or hemorrhoids, so used in short- term treatment. OH OH Mechanism of action Hydroxylation of C-1 and C-8 is essential for activity. Glycosylation is also important (sugar moiety serves to transport the aglycone to the site of action in the large intestine). Emodin has showed anti-neoplastic, anti-inflammatory and anti-angiogenesis activities. Some anthraquinone aglycones including rhein and emodin have also demonstrated antiviral activity. This may explain the traditional use in some viral skin conditions. Undesirable effects It produces griping effect (abdominal spasms), so it’s recommended to prescribe antispasmodic with it. Renal stones may develop due to high oxalic acid content. Contraindications The drug should not be used during pregnancy and lactation. Pharmaceutical preparations