葛根蛋白提取工艺及其体外抗氧化性研究

以葛根为原料提取葛根蛋白,以葛根蛋白提取率为指标对4种不同提取工艺进行对比,采用Box-Behnken响应面试验设计,优化葛根蛋白提取工艺,对葛根蛋白进行体外抗氧化分析,并以十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)测定葛根蛋白分子量。结果表明葛根蛋白最佳提取工艺为:提取温度45℃,提取时间2 h,料液比1∶20(g/mL),pH3.5;测得葛根蛋白提取率为11.73%;抗氧化试验表明,葛根蛋白具有良好的羟基自由基和DPPH自由基清除效果,其清除率分别为(88.62±0.73)%、(51.15±0.32)%,且清除DPPH自由基和羟基自由基的IC50分别为0.78、1.89 mg/mL,并具有一定的还原能力;SDS-PAGE试验结果可清晰看见葛根蛋白条带,分子量主要分布在14.0 kDa~43.0 kDa。

Study on Extraction Technology of Pueraria lobata Protein and Its Antioxidant Activity in vitro

Pueraria lobata was taked as raw material to extract Pueraria lobata protein,the extraction rate of Pueraria lobata protein was used as the index to compare four different extraction processes.The Box-Behnken response surface design was used to optimize the extraction process of Pueraria lobate protein,and the antioxidant activity of Pueraria lobata protein in vitro was analyzed.The molecular weight of Pueraria lobate protein was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE).The results showed that the best extraction technology of Pueraria lobate protein was as follows:extraction temperature 45℃,extraction time 2 hours,ratio of material to liquid 1∶20(g/mL),pH 3.5;the extraction rate of Pueraria lobate protein was 11.73%.Antioxidant experiment showed that Pueraria lobate protein had good scavenging effect of hydroxyl radical and DPPH radical,the scavenging rates were(88.62±0.73)%and(51.15±0.32)%respectively,and the IC50 of scavenging DPPH radical and hydroxyl radical were 0.78 mg/mL and 1.89 mg/mL,and had a certain reduction ability;SDS-PAGE results showed that Pueraria lobata protein bands were clear,and the molecular weight mainly distributed in 14.0 kDa-43.0 kDa.