ABSTRACT
Rhubarb is a perennial herb belonging to the genus Rheum L. (Polygonaceae). Rhei Radix et Rhizoma (rhubarb roots and rhizomes) is one of the most popular Chinese materia medica and has been widely used for strong laxative function. About 200 compounds with six different types of skeletons (anthraquinone, anthrone, stilbene, flavonoids, acylglucoside, and pyrone) have so far been isolated from eighteen species of the genus Rheum L. These constituents showed extensive pharmacological activities including cathartic, diuretic, anticancer, hepatoprotective, anti-inflammatory, and analgesic effects, as well as toxicological effects. Chemical fingerprint, LC-MS, and other analytical techniques have been used for the quality control of rhubarb. This comprehensive review summarizes the researches into the isolation, pharmacological activities, and phytochemical analysis reported since investigations began in the late 1940s. In addition, pharmacokinetic studies and clinical application of rhubarb are also discussed in present paper. © 2013 Tianjin Press of Chinese Herbal Medicines.
ABSTRACT
Objective To isolate and determine the structures of chemical constituents from the roots and rootstalks of Rheum emodi.Methods The chemical constituents were isolated and purified by silica gel and polyamide column chromatography.Chemical methods and spectroscopic methods,such as 1H-NMR,13C-NMR,and MS spectra were used for the structure identification.Results Eighteen compounds were obtained.Sixteen of them were identified as:chrysophanol(1),physcion(2),?-sitosterol(3),emodin(4),aloe-emodin(5),rheumin(6),daucosterol(7),d-catechin(8),piceatannol(9),piceatannol-4'-O-?-D-glucopyranoside(10),piceatannol-4'-O-?-D-(6″-O-p-coumaroyl)-glucopyranoside(11),chrysophanol-8-O-?-D-glucopyranoside(12),physcion-1 and 8-O-?-D-glucopyranoside(13a and 13b),emodin-8-O-?-D-glucopyranoside(14),and sucrose(15).Meanwhile,one compound structure simi-lar to rhein was detected.Conclusion Compound 11 is a new compound named rheoside,compounds 13a and 13b are obtained from R.emodi for the first time.
ABSTRACT
Object In order to identify the resources of official and unofficial plants in Rheum L.at molecular level, a random amplified polymorphic DNA (RAPD) analysis was performed. Methods The amplification program of polymerase chain reaction (PCR) was optimized. Arbitrary decamer primers of 121 based on the individual selecting method, and 64 based on the BSA method were screened. Results Four primers among all screened primers were found to be useful to amplify specific strips to the official plants of Rheum L. Conclusion This method is reliable, accurate, quick and reproducible for authenticating the official and unofficial plants of Rheum L. at molecular level. Moreover, the experiment results indicate that it is more effective to screen the primers using BSA method than using individual selecting method.