超声辅助乙醇提取海带多酚工艺优化及抗氧化活性

Optimization of Ultrasonic-assisted Ethanol Extraction of Polyphenols from Kelp and Their Antioxidant Activities

探究超声辅助乙醇提取海带多酚的工艺条件,选取超声温度、料液比、超声时间和乙醇浓度为试验因子,研究不同工艺参数对海带多酚提取量的影响,并采用响应面法优化海带多酚的提取工艺,通过测定其对DPPH自由基及ABTS的清除作用,评价其抗氧化活性。结果表明,超声辅助乙醇提取海带多酚的最佳工艺条件为:超声温度65.0℃、料液比1∶28(g/mL)、超声时间45 min、乙醇浓度75%,在此条件下海带多酚提取率为2.118 mg/g,接近模型预测值2.139 mg/g。海带多酚对DPPH自由基和ABTS的清除率分别为68.87%和49.73%,IC 50相应为81.119μg/mL和222.224μg/mL,其清除能力与多酚浓度之间呈一定的正相关关系,海带多酚具有一定的体外抗氧化能力。超声波辅助乙醇提取海带中多酚的方法可行、可靠,试验为海带生物活性成分的高效制备与抗氧化剂的深度开发提供了理论依据。

In this paper,the process conditions of ultrasonic-assisted ethanol extraction of polyphenols from kelp are discussed,the ultrasonic temperature,solid-liquid ratio,ultrasonic time and ethanol concentration are selected as the test factors to study the effects of different process parameters on the extraction amount of polyphenols from kelp.Response surface method is used to optimize the extraction process of kelp polyphenols,the antioxidant activities are evaluated through measuring their scavenging effects on DPPH radical and ABTS.The results show that the optimal technological conditions for ultrasonic-assisted ethanol extraction of polyphenols from kelp are as follows:the extraction temperature is 65℃,the solid to liquid ratio is 1∶28(g/mL),the extraction time is 45 min,and the ethanol concentration is 75%.Under the optimal extraction conditions,the extraction rate of kelp polyphenols is 2.118 mg/g,which is close to the predicted value 2.139 mg/g.The scavenging rate of kelp polyphenols to DPPH free radical and ABTS is 68.87%and 49.73%respectively,and the corresponding IC 50 value is 81.119,222.224μg/mL respectively,and there's a positive correlation between scavenging capacity and polyphenols concentration,kelp polyphenols have certain antioxidant ability in vitro.Ultrasonic-assisted ethanol extraction of polyphenols from kelp is feasible and reliable,this experiment has provided a theoretical basis for the efficient preparation of bioactive components of kelp and the in-depth development of antioxidants.