复合酶协同超声提取藜麦皂苷及其抗氧化性

Complex Enzyme Assisted Ultrasonic Extraction of Saponins from Quinoa Husk and Its Antioxidant Activity

采用复合酶协同超声提取藜麦种皮皂苷,并对其抗氧化活性进行了测定。以藜麦皂苷的提取率为指标,考察了酶配比m(纤维素酶)∶m(果胶酶)、酶用量、酶解温度、pH、酶解时间对藜麦皂苷提取率的影响,并用响应面法进行了优化。得到最佳工艺条件为:总酶用量(以藜麦种皮质量为基准,下同)为1.5%,酶配比m(纤维素酶)∶m(果胶酶)为3∶2,酶解温度为50.5℃,pH为5.5,酶解时间为0.25 h。在该条件下,藜麦皂苷的提取率较高,达到85.32%;该法对藜麦种皮皂苷的提取率比单一纤维素酶提取率(81.56%)高4.41%,比单一果胶酶提取率(82.20%)高3.66%,比单独超声提取率(73.07%)高16.76%。采用清除1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的能力,分析藜麦皂苷的抗氧化活性,结果表明,藜麦皂苷具有显著的抗氧化活性,且与皂苷的质量浓度呈剂量依赖性。

Saponins were extracted from quinoa husk using complex enzyme assisted ultrasonic technology and its antioxidant activity was measured.The effects of enzyme ratio(mass ratio of cellulase to pectinase),enzyme dosage,enzyme hydrolysis temperature,pH value and enzyme hydrolysis time on the extraction yield of quinoa saponins by single factor experiment.On the basis of the single factor experiment,response surface methodology was used to optimize the technical parameters,and the optimum parameters were as follows:total enzyme dosage(based on the mass of quinoa husk,the same below)1.5%,enzyme ratio(mass ratio of cellulase to pectinase 3∶2),enzyme hydrolysis temperature 50.5℃,pH=5.5,and enzyme hydrolysis time 0.25 h.Under these optimum conditions,the extraction yield of quinoa saponins reached a maximum of 85.32%,which was 4.41%higher than that using only cellulase(81.56%),3.66%higher than that using only pectinase(82.20%),and 16.76%higher than that using only ultrasonic extraction(73.07%).The antioxidant activity of the extracted saponins was evaluated by DPPH·.The results showed that the saponins extracted from quinoa husk had significan antioxidant activitiy,and saponins’concentration and antioxidant activity was in a dose-dependent manner.