Study On The Bioactivities And Chemical Constituents Of The Oxalis Corymbosa DC

Oxalis Corymbosa DC is an important medicinal plant with good antisepsis and anti-inflammation function. It is reported that Oxalis Corymbosa DC has good antioxidant and antibacterial activity, but rare researches have been carried out for pharmacological effects of Oxalis Corymbosa DC and traditional usage pattern has been applied till now; analysis of chemical components is still at the preliminary stage presently. In order to make better use of previous Oxalis Corymbosa DC, its biological activity was systematically analyzed and chemical components of the rhizome were studied and analyzed. The main results were shown below:Analysis of biological activityExtract rhizome, leaf and flower of Oxalis Corymbosa DC by ethanol and dissolve them with a proper amount of water and extract the extractum. Then extract it with petroleum ether(PE), chloroform, ethyl acetate(EA) and n-butylalcohol successively, dry it and obtain 15 samples to be analyzed. Test antioxidant activity, bacteriostatic activity and antitumor activity in vitro of 15 samples.Test samples' scavenging activity to DPPH free radical in the antioxidant activity test. According to analysis, rhizome, leaf and flower of Oxalis Corymbosa DC had a good scavenging activity to DPPH free radical, besides, ethyl acetate phase and chloroform phase contained had a good activity, while water phase and n-butyl alcohol phase contained had an inferior activity; rhizome had a stronger scavenging activity to DPPH free radical than leaf and flower.Bacteriostatic activity of Oxalis Corymbosa DC extractive was analyzed and determined by oxford cup method and tube dilution method in this paper. Oxalis Corymbosa DC had good bacteriostatic action on 5 bacteria to be tested(escherichia coli, staphylococcus aureus, pseudomonas aeruginosa, bacillus proteus vulgaris and Klebsiella pneumoniae). It was also discovered that ethyl acetate phase and chloroform phase contained in the extractives by different solvents had a good bacteriostatic action, and water phase had an inferior bacteriostatic activity.Antitumor activity in vitro of Oxalis Corymbosa DC extractive was analyzed with MTT method. The results showed, Oxalis Corymbosa DC had no inhibiting effect on growth of cancer cells; thus, Oxalis Corymbosa DC has weak cytotoxicity and may be rich in nutrient substances.Analysis of chemical componentsAccording to activity analysis, rhizome of Oxalis Corymbosa DC had good biological activity, so this paper mainly analyzes and studies chemical components of rhizome.After extraction and phase splitting of rhizome of Oxalis Corymbosa DC, 13 major volatile components were obtained from GC-MS analysis of petroleum ether phase. Petroleum ether phase, chloroform phase, ethyl acetate phase and n-butyl alcohol phase were separated and purified with separation methods such as ODS column chromatography, silica gel column chromatography, gel(Sephadex LH-20) column chromatography and thin layer chromatography and the chemical strcuture was identified. 18 compounds were obtained from separation and received spectrum analysis, and corresponding chemical structure was determined. The seven compounds were timnodonic acid, palmitic acid, catechin, L-epicatechin, ?-spinasterol, 3- Benzyl- 6-(3,4,5- trihydroxy-6- methyl- tetrahydro-pyran-2-yloxymethyl)-tetrahydro- pyran-2,3,4,5-tetraol. These compounds were obtained from this plant for the first time.