纤维素酶法提取决明子粗多糖的工艺优化及其抗氧化活性

目的:优化纤维素酶法提取决明子粗多糖的工艺,并研究决明子粗多糖的体外抗氧化活性。方法:在单因素实验的基础上,以酶解时间、酶解温度、酶用量、液料比及酶解pH为自变量,多糖得率为响应值,利用BoxBehnken响应面法进行工艺优化。以对DPPH自由基和羟自由基清除率的大小为指标考察决明子粗多糖的体外抗氧化活性。结果:纤维素酶法提取决明子粗多糖最佳工艺为酶用量1.4%、酶解时间50 min、液料比24:1 mL/g、酶解pH5.4、酶解温度48℃,此条件下决明子多糖得率为11.67%,与回归模型的理论预测值11.91%误差小于5%。决明子粗多糖对DPPH自由基和羟自由基均具有较强的清除作用,半数抑制浓度分别为1.025 mg/mL和0.894 mg/mL。结论:纤维素酶法可显著提高决明子粗多糖得率,工艺简便可行,获得的决明子粗多糖具有体外抗氧化活性。

Optimization of Cellulase Extraction Process of Crude Polysaccharide from Semen Cassiae and Study on Its Antioxidant Activity

Objective: To optimize the cellulase extraction process of crude polysaccharide from Semen Cassiae and study its antioxidant activity in vitro. Methods: On the basis of single factor test results, Box-Behnken response surface methodology was used to optimize the extraction process of crude polysaccharide from Semen Cassiae with enzymolysis time, enzymolysis temperature, enzyme dosage, liquid-to-material ratio and enzymolysis pH as independent variables, and the yield of polysaccharide as response value. DPPH radical and hydroxyl radical scavenging rates were used to investigate the antioxidant activities of crude polysaccharides from Semen Cassiae in vitro. Results: The optimal cellulase extraction conditions of crude polysaccharide from Semen Cassiae were as follows: Enzyme dosage was 1.4%, enzymolysis time was 50 min, liquid-to-material ratio was 24:1 mL/g, enzymolysis pH was 5.4, and enzymolysis temperature was 48 ℃. Under these conditions, the yield of polysaccharide from Semen Cassiae was 11.67%, and the theoretical prediction value of regression model was 11.91%, the error between the two conditions was less than 5%. Crude polysaccharide from Semen Cassiae had strong scavenging effects on DPPH free radical and hydroxyl free radical, with median inhibitory concentrations of 1.025 mg/mL and 0.894 mg/mL, respectively. Conclusion: Cellulase enzymatic method can significantly improve the yield of crude polysaccharide from Semen Cassiae, the process is simple and feasible, and the crude polysaccharide obtained from Semen Cassiae has antioxidant activity in vitro.