【摘要】 通过DPPH·法测定葡萄籽梯度提取各组分清除自由基能力的研究,结果表明,最佳活性测定样品浓度范围1.0-10μg/mL、放置时间30min、温度25℃,运用此法测得的清除率在25-80%之间,具有较高的灵敏度和准确度。样品浓度0.25-10μg/mL与活性呈正相关关系,其中从1.0-5.0μg/mL范围内有良好的线性关系。当样品用量低于25μg/mL时,样品自身的贡献微不足道,清除率按公式:IP(%)=[(Ac-Ai)/Ac]×100计算。浓度大于25μg/mL时,其结果计算必须扣除样品背景影响IP(%)=[1-(Ai-Aj)/Ac]×100%,否则可能得出样品无抗氧化性或有助氧化作用的错误结论。更多还原

【Abstract】 In this article the study of the free-radical scavenging effects of the different components from grape seeds by DPPH· method was conducted and the resulted showed that the optimum assay range was (1-10μg/ml), time 30min., Temp. 25℃. The scavenging yield was between 25-80%. The sensitivity and the accuracy of this assay method were high. The concentration of the samples were controlled as 0.25-10μg/ml, and showed a positive relationship with activity. There was a linear relationship among the range of (1.0-5.0μg/ml). When the amount of samples was below 25μg/ml, the contribution of sample itself to the A value could be ignored. The scavenging yield could be calculated as the following formula: IP(%)=[(Ac-Ai)/Ac]×100. When the concentration of the sample was over 25μg/ml, the scavenging yield should be calculated by using the formula as follows: IP(%)=[1-(Ai-Aj)/Ac]×100%, here the influence of the sample itself should be considered, otherwise a wrong conclusion of being no antioxidant or oxidant enhancer might be drown.更多还原