乌桕叶抽提物体外抗氧化活性的研究

为了开发国产特色资源乌桕,综合利用乌桕叶,以90℃热水、70%乙醇、乙酸乙酯提取不同乌桕品种叶材料中的抗氧化物质,用清除羟自由基模型、抑制亚油酸过氧化模型和铁氰化钾还原力模型评价抗氧化活性。结果表明:70%乙醇浸提物和热水提取物显示出较强的还原力(200μg/ml样液相当于2×10-4mol/L的硫脲)和清除羟自由基活性(4mg/ml样液清除率:热水提取物为42.41%～63.62%,醇提取物为20.71%～54.49%),且极大地相关于所含的类黄酮含量(水提物上述两种抗氧化性与类黄酮含量相关性系数分别为:0.7793、0.8258;醇的分别为:0.8319、0.9335)。抑制亚油酸过氧化以乙酸乙酯提取物较强。乌桕叶提取物可望开发抗氧化剂和健康佐剂。

To exploit Chinese tallow resource with native characteristics and to use its leaf synthetically, antioxidant-rich fractionswere extracted respectively from Chinese tallow leaf by various solvents, such as water at 90℃, 70% ethanol in water and ethylacetate (EtOAc). The antioxidant activities of the extracts were evaluated respectively by hydroxyl radical scavenging activitymethod, the linoleic acid peroxidation prevention method and reducing power method. At 4 mg/ml concentration, various extractswith 90℃ water and 70% ethanol in water showed 42.42%～63.62% and 20.71%～54.49% hydroxyl radical scavenging activityrespectively. These extracts also showed good reducing power at 200μg/ml concentration, equal to 2×10-4mol/L Tu, by the potassiumferricyanide reduction method. The extract with EtOAc was superior to the others in preventing the peroxidation of linoleic acid.Chinese tallow leaves extracts might be exploted for antioxidant and health supplements.