豇豆多糖的超声辅助提取条件优化及体外抗氧化研究

Optimization of Ultrasonic Assisted Extraction of Cowpea Polysaccharide and Study on Its Anti-oxidation in Vitro

利用超声波辅助技术研究豇豆多糖的最佳提取工艺,并对其抗氧化活性进行评价,旨在为豇豆多糖的研究及开发利用提供参考。首先,通过单因素试验考察超声时间、超声功率、提取温度、提取时间、料液比对豇豆多糖得率的影响;其次,在单因素试验的基础上,采用响应曲面法设计三因素三水平试验进行回归分析,优化豇豆多糖的提取工艺;最后,以羟基、DPPH、ABTS自由基和铁离子还原能力法评价其体外抗氧化活性。结果表明:在超声时间为5min、超声功率为额定功率的50%的条件下,Design-Expert 8.0.6模型预测计算各因素最优,提取条件为:提取时间2h,提取温度93℃,料液比1∶42,在此条件下得到的多糖得率为7.65%,与常规热水提取得率相比明显上升。豇豆多糖(CPP)在0~5mg·mL^(-1)范围内对羟基自由基的清除率呈量效正相关,CPP浓度为5mg·mL^(-1)时清除率达到最高,为57%,CPP的IC50为4.85mg·mL^(-1);对DPPH自由基的清除能力呈量效正相关,当其浓度为5mg·mL^(-1)时清除率达到最高,为75%,CPP的IC50为2.51mg·mL^(-1);对ABTS自由基清除力先升高后降低,当CPP浓度达到3mg·mL^(-1)时清除能力最高,为78%,CPP的IC50为1.35mg·mL^(-1)。CPP浓度在0~3mg·mL^(-1)范围内,总还原力明显增强,在3~5mg·mL^(-1)范围内总还原力比较稳定,当CPP的浓度为3mg·mL^(-1)时,还原力达到最高为99.4%,CPP的IC50为1.61mg·mL^(-1)。

Using ultrasound-assisted technology to study the best extraction process of cowpea polysaccharides and evaluate its antioxidant activity,aiming to provide reference for the research and development of cowpea polysaccharides.First,the effects of ultrasonic time,ultrasonic power,extraction temperature,extraction time,and material-to-liquid ratio on the yield of cowpea polysaccharides were investigated through single-factor experiments;secondly,on the basis of single-factor experiments,the response surface method was used to Use response surface methodology to design a three-factor three-level test for regression analysis to optimize the extraction process of cowpea polysaccharides to optimize the extraction process of cowpea polysaccharide;Finally,the in vitro antioxidant activity was evaluated by hydroxyl,DPPH,ABTS free radical and iron ion reduction ability method.The test results show that,under the condition that the ultrasonic time is 5min and the ultrasonic power is 50%of the rated power,the Design-Expert 8.0.6 model predicts and calculates the optimal extraction conditions for each factor:extraction time 2h,extraction temperature 93℃,material liquid The ratio is 1∶42,and the yield of polysaccharide obtained under this condition is 7.65%,which is significantly higher than that of conventional hot water extraction.The scavenging rate of cowpea polysaccharide(CPP)on hydroxyl radicals in the range of 0-5mg·mL^(-1) is positively correlated with a dose-effect.When the concentration of CPP is 5mg·mL^(-1),the scavenging rate reaches the highest 57%,and the IC50 of CPP is 4.85 mg·mL^(-1);the scavenging capacity of DPPH free radicals is positively correlated with a dose-effect.When its concentration is 5mg·mL^(-1),the scavenging rate reaches the highest 75%,and the IC50 of CPP is 2.51mg·mL^(-1);for ABTS The scavenging ability of free radicals increases first and then decreases.When the concentration of CPP reaches 3mg·mL^(-1),the scavenging ability is up to 78%,and the IC50 of CPP is 1.35mg·mL^(-1).The total reducing power is significantly enhanced when the CPP concentration is in the range of 0-3mg·mL^(-1),and the total reducing power is relatively stable in the range of 3-5mg·mL^(-1).When the CPP concentration is 3mg·mL^(-1),the reducing power reaches The highest is 99.4%,and the IC50 of CPP is 1.61mg·mL^(-1).