Optimization of extraction parameters of phenolic antioxidants from defatted grape seed flour by response surface methodology

The response surface methodology (RSM) was used to search for the optimal conditions for solid-liquid extraction of phenolic compound from defatted grape seed flour under the influence of three factors: temperature (60-100 C) and time (90-150 minutes) of extraction, ratio of solvent to mass of powder ( 60-100).
The total antioxidant capacity (TAC) and the total content of polyphenolic compounds (TPC) of the samples were determined by coulometric titration in galvanostatic mode with electrogenerated bromine and spectrophotometric method using Folin-Ciocalteu reagent, respectively. Experimental values ​​of TAC and TPC were presented in terms of the equivalent of the content of gallstone (GAE) per unit mass of powder (DW).

本研究采用响应面法（response surface methodology, RSM），筛选脱脂葡萄籽粉中酚类化合物固液萃取的最优工艺条件，考察的影响因素包括萃取温度（60~100℃）、萃取时间（90~150 min）以及溶剂与粉料质量比（60~100）。分别采用恒电流模式下电生溴库仑滴定法测定样品的总抗氧化能力（TAC），并通过福林-酚（Folin-Ciocalteu）试剂分光光度法测定样品的总多酚含量（TPC）。实验所得TAC与TPC结果均以每单位粉料干重（dry weight, DW）的没食子酸当量（GAE）表示。