Chemical constituents from the ethyl acetate extract of Cynanchum komarovii Al.Iljinski and their antioxidant and tyrosinase inhibitory activities
In order to systematically explore the active ingredients of the medicinal plant Cynanchum komarovii Al.Iljinski,compounds were isolated by various chromatographic techniques from the ethyl acetate extraction of C.komarovii whole plant,and their antioxidant and tyrosinase inhibitory activities were also studied.As a result,ten compounds were obtained and their structures were identified by spectroscopy methods as 3-methoxy-4-hydroxyacetophenone(1),3,4-dimethoxyacetophenone(2),6,7-dimethoxycoumarin(3),6-methoxy-7-hydroxycoumarin(4),p-hydroxypropiophenone(5),p-hydroxyacetophenone(6),10a,12a-dimethyl-4,4a,4b,10b,11,12-hexahydro-3H-naphtho[2,1-f]chromene-2,8-dione(7),ent-13S-hydroxy-16-atisene-3,14-dione(8),3-indole formaldehyde(9),trans-cinnamic acid(10).Compounds 7-10 were isolated from C.kom-arovii for the first time.The antioxidant and anti-tyrosinase activities of these compounds were investigated by using the DPPH free radical method and colorimetric method with L-tyrosine as substrate.The results showed that compounds 1,2,4 and 5 have certain scavenging ability on DPPH free radicals with the IC50 of 37.3,44.3,51.4 and 48.2 μg/mL,respectively.Com-pounds 1,2,3,4 and 6 showed significant tyrosinase inhibitory effects with the IC50 of 15.7,22.3,8.3,7.1 and 39.8 μg/mL,respectively,which were stronger than the positive control arbutin.
万方数据
维普
