蛇附子化学成分及抗氧化活性研究

Chemical constituents in root tuber of Tetrastigma hemsleyanum and their anti-oxidative activities

目的研究蛇附子（三叶崖爬藤Tetrastigma hemsleyanum的块根）的化学成分及抗氧化活性。方法采用多种色谱技术对其进行分离纯化,应用1H-NMR、13C-NMR、MS、HR-MS等波谱学方法进行结构鉴定;利用DPPH法进行抗氧化活性测定。结果从蛇附子80%甲醇提取物中分离得到14个化合物,分别鉴定为山柰酚（1）、槲皮素（2）、水杨酸（3）、苯甲酸（4）、氧化白藜芦醇（5）、儿茶素（6）、表儿茶素（7）、表没食子儿茶素（8）、原花青素B2（9）、原花青素B1（10）、绿原酸（11）、原儿茶醛（12）、对羟基苯甲酸（13）、原儿茶酸（14）;其中化合物2、8、9、10、12抗氧化活性IC50值分别为14.15、14.19、15.99、12.4、15.98μmol/L,优于阳性药维生素C（IC50值为23.0μmol/L）。结论化合物4~12均系首次从该植物中分离,得到蛇附子中除了黄酮类成分外,也富含较多的有机酸类成分;并且化合物2、8、9、10、12抗氧化活性良好。

Objective To study the chemical compositions from the root tuber of Tetrastigma hemsleyanum and their anti-oxidative activities. Methods The compounds were isolated by various column chromatography. Their structures were identified by spectroscopic methods including 1H-NMR, 13C-NMR, MS, HR-MS, etc. The anti-oxidative activities were evaluated by DPPH radical scavenging assay. Results Fourteen compounds were isolated from the root tuber of T. hemsleyanum, they were identified as kaempferol（1）, quercetin（2）, salicylic acid（3）, benzoic acid（4）, oxyresveratrol（5）, catechin（6）, L-epicatechin（7）, epigallocatechin（8）, procyanidin B2（9）, procyanidin B1（10）, 3-O-caffeoylquinic acid（11）, protocatechualdehyde（12）, p-hydroxybenzoic acid（13）, and protocatechuic acid（14）. The anti-oxidative IC50 values of compounds 2, 8, 9, 10, and 12 were 14.15, 14.19, 15.99, 12.4, and 15.98 μmol/L, respectively, better than the positive control Vit C（IC50 value was 23.0 μmol/L）. Conclusion Compounds 4—12 are isolated from T. hemsleyanum for the first time. It has been demonstrated that the root tuber contain flavonoids and also is rich in organic acids. Moreover, compounds 2, 8, 9, 10, and 12 have the certain prospects in the development of natural anti-oxidative agents.