ABSTRACT
Introduction: Rheum palmatum L. var. tanguticum Maxim. (Polygonaceae) is one of the well-known Pharmacopeial plants, which is widely used for treatment and prevention of diseases of the digestive system. It has a wide range of pharmacological activity: antiseptic, increasing appetite, hypotensive, astringent and laxative effects. The aim of this work is to make a Pharmacognostic analysis of radices Rhei tangutici. To achieve this goal we should make the following tasks:1) to do macro- and microscopic analysis; 2) to make purity tests of plant material; 3)to identify the presence of main biologically active substances; 4) to make a chemical assay of anthracene derivatives in radices Rhei tangutici.A homeland of Rheum tanguticum is Central China and northeastern Tibet. Radices rhei contain 2 - 6% of antraglikosides, a number of which increases with age. Also they contain tannins, resins, pectin substances and a lot of starch. Antraglikosides have a laxative effect which is caused mainly by emodin, rhein and chrysophanic acid (they irritate interoceptors of colon which causes the strengthening of vermicular movement) [1].For the research we used radices Rhei tangutici which were collected in Mongolia in 2012. A plant material is pieces of roots and rhizomes with cylindrical, slightly curved forms and a laterally-savoyed surface; the color is dark brown (on a cleavage - yellow-brown), with characteristic aromatic odour. Microscopic analysis revealed that the main diagnostic features are medullarry rays, 2–4 cells in width; phloem consists of thin-walled cells with round containers with slime, parenchyma possess cluster crystals of calciumoxalate and starch grains. Also we made purity tests and identified moisture - 7% (should be not more than 12%), total ash – 7,8% (not more than 8%), 10% chlorohydric acid-insoluble ash – 0,9% (not more than 1%), roots which discolored to black - 2% (not more than 5%), foreign organic matter 0.1% (not more than 0.5%) and 0.1% of mineral impurity (not more than 0.5%) [2]. In this material we found out the presence of anthracene derivatives (emodin and chrysophanic acid), polysaccharides, tannins and flavonoids using standard identity tests [3]. According to the quantitative analysis of anthracene derivatives in radices Rhei tangutici, performed by spectrophotometry, it contains2.8 - 3.03% calculated as istizin (should be not less than 2%) [2].Thus, the main Pharmacognostic analysis’ characteristics of radices Rhei tangutici, which grows in Mongolia, conform to the pharmacopeial article ¹ 68 (State Pharmacopoeia of the USSR, ed.11, part 2).References:1. Korenskaya I.M., Ivanovskaya N.P. Medicinal plants and medical plant material containing anthracenes, phenols, lignans, tannins. - Voronezh: Publishing center of Voronezh State University, 2007. - 87 p.2. State Pharmacopoeia of the USSR. Ed. XI (part 2). Common methods of analysis. Medical plant material / USSR Ministry of Health. - 11th ed., Ext.- Moscow: Medicine, 1990. - 400 p.3. Grinkevich N.I., Safronich L.N. Chemical analysis of medical plants. -Moscow: Higher school, 1983.- 176p.