不同发酵茶体外α-葡萄糖苷酶和巨噬细胞泡沫化抑制活性初步研究

Studies of Different Fermented Tea Products on the Inhibitory Activities toward α-Glucosidase and Transformation of Macrophage-to-Foam Cells

采用白叶单枞茶鲜叶为原料,按照常规加工工艺分别制成乌龙茶、红茶和黑茶3种不同发酵茶。对这3种茶的水提物,以麦芽糖为底物,采用比色法测定了其体外对α-葡萄糖苷酶的抑制活性,结果显示抑制活性从高到低依次为红茶、黑茶、乌龙茶。采用体外培养小鼠巨噬细胞系Raw264.7细胞,以氧化低密度脂蛋白诱导建立泡沫细胞模型,分别用3种茶水提物进行干预,酶法测定细胞内总胆固醇含量的变化,探讨了3种茶对细胞因过量摄取胆固醇而致泡沫化的抑制作用。结果显示,黑茶、红茶和乌龙茶对巨噬细胞泡沫化的抑制率分别为73.29%、62.31%和51.93%。

Oolong tea,black tea and dark tea were prepared from Camellia sinensis var.baiye dangcong according to their corresponding manufacturing processes,respectively.The in vitro inhibitory activities of the water extracts from the three tea products towards α-glucosidase were investigated by Colormetry using maltose as the substrate.Black tea and dark tea showed higher inhibitory activities than oolong tea.On the other hand,the mouse Raw264.7 cells were induced into foam cells by incubation with oxidized low density lipoprotein to examine the protective effects of the three tea products.The cellular contents of total cholesterols was detected by enzymatic colorimetry.The results showed that dark tea processed the highest inhibitory activity on transformation of macrophage-to-foam cells.The inhibitory rates of dark tea,black tea and oolong tea were observed to be 73.29%,62.31% and 51.93%,respectively.