Comparision Study On Chemical Composition Of Hedyotis Diffusa And Hedyotis Corymbosa (Linn.) Lamarck

Traditional Chinese herbal medicine is a specific drug, which can be incorporated into the theoretical system of traditional Chinese medicine. Traditionally, TCM has been the main method to prevent and cure of diseases. Owing to the theroy of"to address both the symptoms and root causes", more and more attention has been paid to TCM study these years. However, due to its long usage history, broad distribution and wide varieties, many so called defects as"suit the remedy to the case, but it has not curative effect"emerges. Quality control is the key measure to resolve the problem.Hedyotis diffusa and Hedyotis corymbosa (Linn.)Lamarck are members of the the Hedyotis L. family. Because the two herbs have similar plant origin, it is difficult to distinguish between them. Sometimes, Hedyotis diffusa was taken as Hedyotis corymbos a (Linn.) Lamarck that led to serious clinical problems. There is an urgent need to establish efficient method to distinguish between the two herbs.There are many methods to identify herbs, including source identification method, original identification method, microscopic identification method and physical-chemical identification method. Source identification, character identification and microscopic identification are very effective methods to identify species which have large species variation. But these methods are strongly dependent on the experience of experts. Therefore, limitation of these methods in identification similary species is obvious. Physical-chemical identification is a method which uses physical or chemical instruments. Here, we set up chromatographic methods to distinguish between Hedyotis diffusa and Hedyotis corymbosa(Linn.) Lamarck. Compared to other methods, chromatographic method has the characteristic of high specificity, high sensitivity and good reproducibility.Hedyotis diffusa and Hedyotis corymbosa(Linn.)Lamarck were extract by using continous ethanol heat reflux method. Crude extracts were fractionated by preparative High Performance Liquid Chromatography (HPLC). Compounds from characteristic peaks in each herb were isolated and chemical structures were determined by mass spectrometry (MS), 1H-nuclear magnetic resonance (NMR) and 13C NMR. Furanocoumarins hedyotiscones A (X) in Hedyotis corymbosa(Linn.)Lamarck and 2-hydroxy-3-methyl anthraquinone (S) in Hedyotis diffusa were determined as characteristic compounds of the two herbs, respectively. In addition, high-speed counter-current chromatography (HSCCC) was used to isolate and purify compounds from high hydrophilic crude extracts of the Hedyotis diffusa and Hedyotis corymbosa(Linn.)Lamarc.. Two-phase solvent system of HSCCC contains butanol - ethyl acetate - water (5: 4:10). Four compounds including quercetin 3-O-sophoroside (S1),Quercetin -3-O-[2-O-(6-O-E-sinapoyl) -β-D- glucopyranosyl]-β-D-glucopyranoside (S2),S3,S4 were isolated from Hedyotis diffusa, and four compounds including quercetin 3-O-sophoroside (X1),X2,Quercetin 3-o-[(6-o-trans- feruloyl-β-glucopyranosyl) -(1â†'2)-β-arabinopyranoside] -7-o-β-glucopyranoside (X3),Quercetin 3-o-[(6-o-trans-p-hydroxy -cinnamoyloay-β- glucopyranosyl) -(1â†'2)-β-arabinopyranoside]-7-o-β-glucopyranoside (X4) were isolated Hedyotis corymbosa(Linn.)Lamarck. Purities of the compouns are as following: 96%,92%,90%,92%,93%,96%,94%,91%. Chemical structures of the compounds were determined by MS and NMR methods. quercetin 3-O-sophoroside (X1),Quercetin 3-o-[(6-o - trans-feruloyl-β-glucopyranosyl) -(1â†'2) -β-arabinopyranoside] -7-o-β- glucopyranoside (X3) and Quercetin 3-o- [(6-o-trans-p -hydroxy- cinnamoyloay-β- glucopyranosyl) -(1â†'2) -β- arabinopyranoside] -7-o-β- glucopyranoside (X4) were first identified in Hedyotis corymbosa (Linn.)Lamarck.