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).

采用响应面法（RSM）在三个因素（温度（60-100°C）和提取时间（90-150分钟）以及溶剂与粉末质量比（60-100）的影响下，对脱脂葡萄籽粉中酚类化合物的固体-液体提取进行了最优条件搜索。样品的总抗氧化能力（TAC）和总多酚化合物含量（TPC）分别通过电化学滴定法在恒电流模式下使用电生成的溴和福林-西奥法试剂的比色法进行测定。TAC和TPC的实验值以每单位粉末（DW）中草酸（GAE）含量当量表示。