Research On The Chemical Components And Its Antioxidant Activities In Vitro Of Oreorchas Patens

Oreorchis patens(Lindl.)Lindl.,perinial herbaceous shade plants,belongs to Oreorchis genus,Orchidaceae family,and its dry pseudobulb is one kind of Traditional Chinese medicine(TCM),which is widely distributed in Southwest China,central China,Northeast China ect.TCM drug Shancigu is from the three kinds of plants,they are Cremastra appendiculata(D.Don)Makino,Pleione bulbocodioides(Franch.)Rolfe,P.yunnanensis Rolfe,and their medicinal parts are also the dry pseudobulbs.Researches show that Shancigu drug has remarkable anticancer activity,so it is the main composition in Traditional Chinese medicine.In market investigation it is found that some TCM drug dealers have begun to buy a large number of Shanlan as Shancigu from the Jilin Changbai Mountain from 2008,and at the same time Shanlan and the three plants are in the Orchidaceae family with close relationship.If the Shanlan could be proved as Shancigu drug,there will be critical theoretical and practical meaning.Therefore,in order to effectively develop Shanlan resources,and study the possibility of Shanlan as Shancigu medicine,the chemical components in Shanlan are analyzed comprehensively.These components are compared with the existed ones in Shancigu for providing theoretical basis of the Shanlan as Shancigu.At the same time the pharmacological activities of different Shanlan extracts were studied for the theoretical basis in a wide application of Shanlan resources to improve its medicinal value.The research's main contents are as follows:1.The components of the different extracts in the Shanlan were isolated and purified with silica gel chromatography of ordinary of reduced pressure,TLC,Sephadex LH-20 columns and recrystallization techniques.Then the structures of the isolated compounds were characterized with their physical-chemical properties and their 1HNMR,13 CNMR and DEPT data.Finally 18 compounds were identified,including ?-sitosterol(1),adenosine(2),emodin(3),dioctyl phthalate(4),butylisobutyl-phthalate(5),5-hydroxy methylfurfural(6),dibutyl terephthalate(7),diamyl phthalate(8),13-henicosene acid methyl ester(9),?-sitosterol acetate(10),p-hydroxybenzoic acid(11),protocatechuic acid(12),dibutyl phthalate(13),hexatriacontane(14),syringaresinol(15),cirrhopetalanthin(16),?-daucosterol(17),pentacosane(18).Compounds 2 to 16 and 18 were isolated from Oreorchas patens for the first time.And comparing with each other,nine of the 18 compounds existed in the four species and the compound 16(with significant anti-cancer activities)was paticularly contained in the Cremastra appendiculata,which also found in the Oreorchis patens.2.The volatile components of petroleum ether extracted from Oreorchas patens were analyzed by GC-MS,and the structures of the isolated compounds were identified with NIST(Library version2.0)Data System and the relative literatures on spectrum analysis.The results showed that 22 compounds were identified,including sterols,esters,fatty acid and etc.Among the compounds,the content of volatile components is the highest,which accounted for 87.238%;and among the volatile components the amount of ?-sitosterol is relatively higher,reaching to 26.883%;the next two are in turn 3-oxo-9b-lanosta-7-en-26,23-olide and n-hexadecane acid,their content are 17.621%,11.692% respectively.3.The total antioxidant capacities of the petroleum ether,ethyl acetate and n-butanol extracts from Shanlan were tested with ammonium molybdate method,and then comparing the data with antioxidant BHT.The the DPPH removal rate and ABTS clearance rate,iron reducing ability of the three extracts were also measured.The antioxidant capacities in the three extracts were analyzed statistically with SPSS 19.0 software.The results show that the total antioxidant capacity gradually increased with the mass-concentration of the petroleum ether,ethyl acetate and n-butanol extracts of Shanlan and BHT,and the antioxidant capacities in turn from high to low are the extracts in n-butanol,ethyl acetate,the petroleum ether;the IC50 of DPPH free radical scavenging activities of the three extracts are 1.301±0.1304 mg/mL,1.531±0.1059mg/mL and 0.661±0.1267mg/mL,and the antioxidant capacities in turn from high to low are the extracts in n-butanol,the petroleum ether,ethyl acetate;the IC50 of ABTS free radical scavenging activities of the three extracts are 1.451 ±0.1254mg/mL,0.551±0.1871mg/mL,0.350±0.1976mg/mL,and the antioxidant capacities in turn from high to low are the extracts in n-butanol,ethyl acetate,the petroleum ether;the reduction ability of the iron ions tends to increase in different extent with the mass-concentration of the three extracts,and when the concentration was 0.4 ~ 0.8mg/mL,the antioxidant capacities in turn from high to low are the extracts in n-butanol,ethyl acetate,the petroleum ether;the petroleum ether fraction is lower by n-butanol and ethyl acetate;when the concentration was 1.0mg/mL,the antioxidant capacities in turn ethyl acetate,n-butanol and petroleum ether.The antioxidant capacities of the three extracts are lower than BHT.