文冠果种仁总皂苷的抗氧化及抗肝癌活性初探

Antioxidant and Anti-hepatoma Activities of Total Saponins from Kernel of Xanthoceras sorbifolia Bunge

本文研究了文冠果种仁总皂苷的体外抗氧化活性及其对人肝癌HepG2细胞的抑制增殖和诱导凋亡作用,为后续文冠果种仁皂苷单体活性研究提供依据。首先通过定性试验证明了所提取的种仁总皂苷为三萜皂苷类物质,浓度为520±19.1 mg/g。其次以Vc作阳性对照,研究文冠果种仁总皂苷的抗氧化活性,结果证明其还原能力强于Vc,而其清除DPPH自由基的能力比Vc要弱。最后采用MTT试验评价皂苷的抗癌活性,结果发现皂苷处理时间为24 h的IC50是9.7±0.39 mg/L;细胞形态学和荧光染色证明了其对HepG2细胞具有凋亡诱导作用,流式细胞仪试验表明癌细胞的晚期凋亡作用可能集中于细胞周期的S期。该试验结果为进一步探索文冠果种仁皂苷的生物活性机理提供理论和试验基础。

In this study, the antioxidant activity in vitro of total saponins in kernel of Xanthoceras sorbifolia bunge and the inhibition of proliferation and apoptosis on HepG2 ceils were studied. Firstly, the contents of extract was proved to con- tain triterpenoid saponin with the concentration of 520 ＋ 19.1 mg/g. Secondly, using vitamin C as a positive control, the antioxidant activity in vitro of total saponins was investigated. The results showed that the reducing power of total sapo- nins in X. sorbifolia kernels was stronger than that of Vc , but the scavenging ability of DPPH free radical was weaker than that of Vc. Finally, the anti-cancer activity of saponins was evaluated with MTI＂ assay. It was found that the optimal pro- cessing time was 24 h and ICs0of total saponins was 9.7 ±0.39 mg/L in the inhibition of total saponins on HepG2 cells. The induced-apoptosis effect of total saponins on HepG2 cells was proved by ceil morphology and fluorescence staining method. The flow cytometry experiments showed that HepG2 ceils apoptosis was happened at later period of cell life and this apoptosis effect may be concentrated in S phase of the cell cycle.