人工胃液作用抗氧化龙井茶多糖的体外模拟研究

Study on Longjing Green Tea Polysaccharides of the Antioxidant Effects in Vitro Simulation Artificial Gastric Juice

以龙井粗老茶叶为材料获得具有抗氧化活性的茶多糖,探讨茶多糖在体外模拟人工胃液中的动态变化过程。粗茶粉经水提醇沉、脱色、除蛋白处理后,依次用不同浓度酒精沉淀,获得抗氧化效果好且得率高的组分TPS70,在体外模拟人工胃液环境中,检测经15,30,45,60,150 min胃酸及胃酶作用时还原糖与分子质量的变化。试验结果表明,茶多糖在体外模拟人工胃液环境中随胃酸与胃酶作用时间的延长,还原糖的量不断缓慢增加。HPLC结果显示,作用15 min时出现小分子糖,作用150 min时大分子茶多糖降解产生稳定的多糖片段与小分子的寡糖片段,表明茶多糖在体外模拟人工胃液环境中随时间作用会发生一定程度的降解,产生还原糖和寡糖片段。本结果为进一步研究茶多糖在生物体内的代谢规律提供参考。

The Longjing coarse tea leaves were material in this thesis, and the antioxidant activity of tea polysaccharide was obtained from these leaves, then the tea polysaccharide in vitro to simulate the dynamic process in the artificial gastric juice was studied. A water-soluble crude polysaccharide（TPS70） with antioxidant activity was gained by water extract-alcohol extraction method, decolorization, removal protein processing and in 70% ethanol precipitation. The molecular weight and the changed of reducing sugars of the tea polysaccharide was detected under in vitro artificial gastric juice at 15 min, 30 min, 45 min, 60 min and 150 min. The result showed that the amount of reducing constantly slow increase as time, and small molecular sugar appeared in the 15 min, while the high molecular changes in the150 min and the stable polysaccharide fragment with small molecular oligosaccharides could produce through HPLC. Tea polysaccharide in artificial gastric juice in vitro degradation environment over time would occur to some extent. This study provides reference for further study on the metabolism of tea polysaccharide in vivo.