Plackett-Burman和Box-Behnken联合优化复合酶辅助超声波提取桑叶总黄酮工艺

Plackett-Burman and Box-Behnken combined to optimize complex enzyme assist ultrasonic extraction of total flavonoids from mulberry leaf

试验研究复合酶法辅助超声提取桑叶中总黄酮的工艺。研究先以芦丁为对照品,比较了盐酸-镁粉法、NaNO2-Al(NO3)3-NaOH法、AlCl3法3种络合方法对桑叶总黄酮的适应性;选用Plackett-Burman试验设计对9个单因素进行筛选,确定了具有显著性影响的3个因素,再根据Box-Behnken试验设计原理,采用3因素3水平的响应面分析法,以桑叶总黄酮得率为响应值进行回归分析。结果表明:AlCl3法对桑叶总黄酮适应性最佳;最佳工艺条件为:复合酶比1:1(w/w)、用酶量为1.0%、pH值为5.0、酶解时间50 min、酶解温度50℃、乙醇浓度71%、超声功率225 W、超声温度60℃、超声时间33 min。在此条件下,桑叶总黄酮得率为27.76 mg/g。优选的提取工艺稳定可行、得率高,为桑叶的深入研究提供参考。

In order to study the extraction technology of total flavonoids from mulberry leaf by combined enzyme assisted ultrasound,rutin was used as the control in the study.The adaptability of three complexation methods to total flavonoids in mulberry leaf was compared[NaNO2-Al(NO3)3-NaOH,Mg-HCl,AlCl3 method].PlackettBurman test design was selected to screen nine single factors,and three factors with significant influence were determined.Then,according to the Box-Behnken experimental design principle,the response surface analysis at the three level of three factors was adopted,and the total flavonoids yield of mulberry leaf was taken as the response value for regression analysis.The results showed that the adaptability of AlCl3 method to total flavonoids of mulberry leaf was the best.The optimal process conditions were:compound enzyme ratio 1:1(w/w),enzyme dosage 1.0%,pH 5.0,enzymatic hydrolysis time 50 min,enzymatic hydrolysis temperature 50℃,ethanol concentration 71%,ultrasonic power 225 W,ultrasonic temperature 60℃,ultrasonic time 33 min.Under these conditions,the total flavonoids yield of mulberry leaf was 27.76 mg/g.The optimized extraction process was stable and feasible with high yield,which provided a reference for further study of mulberry leaf.