龙眼核醋酸乙酯部位的抗氧化活性研究

Study on the Anti-Oxidation Effects of Longan Seeds Ethyl Acetate Fraction

目的研究龙眼（Dimocarpus longan lour.）核醋酸乙酯部位的抗氧化活性。方法通过乙醇提取、醋酸乙酯溶剂萃取、硅胶柱层析等方法，分离提取不同的极性组分（Fr1～Fr16）。运用TBA比色法分别测定了Fr8～Fr16各组分的抗脂质过氧化活性、应用Fenton原理测定了各组分清除羟自由基的活性。结果分离提取得到16个极性不同的组分（Fr1～Fr16），流分Fr8～Fr16对抑制脂质过氧化物、清除羟自由基均具有较好作用，其中部分流分的活性具有量-效关系。最高的抑制率和清除率可达到68．5％。结论龙眼核醋酸乙酯部位的不同流分均具有一定的抑制脂质过氧化作用和清除羟氧自由基作用。

Objective To investigate the anti - oxidative effect of chemical constituents in Longan seed, ethyl acetate fraction. Methods Different fraction constituents of longan seed were obtained by isolating with ethanol solvent, extracting with ethyl acetate and purifying with colomn chromatography and recrystallization and so on. With the help of TBA spectrometric method, effects of ethyl acetate extract from Longan seed on lipid peroxidation were measured by the determination of malondialdehyde （MDA） that was produced by the lipid peroxidation of liver tissue homogenate and mitochondria induced by cysteine - Fe^2＋ system and on scavenging of hydroxyl radical were determined by Fenton system. Results Sixteen constituents of longan seed , ethyl acetate fraction（ Fr1 -Fr16） were obtained. Fraction Fr8 -Fr15 could inhibit the lipid peroxidation of liver tissue homogenate and the lipid peroxidation of mitochondria induced by Fe^2＋ - Cys and scavenge hydroxyl radical. Some fractions＇s activities are in dose - dependent manners. Conclusion Constituents of longan seed , ethyl acetate fraction have good antilipid - peroxidation effect and scavenge hydroxyl radical activity.