响应面法优化圆苞车前子多酚与总黄酮超声提取工艺及其抗氧化活性分析

Optimization of ultrasonic extraction process of polyphenols and total flavonoids from Plantago ovata Forssk by response surface methodology and its antioxidant activity analysis

目的本实验旨在优化圆苞车前子多酚和总黄酮提取工艺,探究圆苞车前子提取物抗氧化活性。方法采用单因素实验结合响应面Box-Behnken设计对圆苞车前子中多酚和总黄酮进行超声辅助提取工艺研究,以多酚及黄酮提取率为指标,利用响应面法得出最佳提取工艺。且通过DPPH、ABTS+自由基的清除能力和总还原能力测定评价其抗氧化能力。结果圆苞车前子多酚与总黄酮提取最佳工艺为:料液比1∶20,提取时间41 min,超声波功率420 W,乙醇体积分数88%。该条件下,多酚的提取量为4.79 mg/g,总黄酮的提取量为23.19 mg/g。抗氧化实验结果表明,圆苞车前子乙醇提取物在2.5~50μg/mL范围内,对DPPH、ABTS+自由基有较好的清除作用,IC50值分别为26.62μg/mL和9.40μg/mL;其总还原能力随着浓度的增加而增强,且始终高于同浓度维生素C的还原能力。结论该提取工艺稳定、可靠,可用于圆苞车前子多酚与总黄酮的提取,且圆苞车前子乙醇提取物具有较好的抗氧化活性。

Objective To optimize the extraction process of polyphenols and total flavonoids from Plantago ovata Forssk,and explore the antioxidant activity of its extracts.Methods Single factor experiments combined with a response surface Box Behnken design were used to study the ultrasonic-assisted extraction process of polyphenols and total flavonoids from Plantago ovata Forssk.The optimal extraction process was determined using response surface methodology with the extraction rates of polyphenols and flavonoids serving as the main indicators.In addition,the antioxidant capacity of the extracts was evaluated by measuring the scavenging ability of DPPH and ABTS+free radicals and the total reducing power.Results The optimal extraction process for polyphenols and total flavonoids from Plantago ovata Forssk were as follows:solid-liquid ratio of 1∶20,extraction time of 41 min,ultrasonic power of 420 W,and ethanol volume fraction of 88%.Under these conditions,the extraction amounts of polyphenols and total flavonoids were 4.79 mg/g and 23.19 mg/g,respectively.The antioxidant experiment results showed that the ethanol extract of Plantago ovata Forssk had good scavenging effects on DPPH and ABTS+free radicals in the range of 2.5-50μg/mL,with the IC50 values of 26.62μg/mL and 9.40μg/mL,respectively.The total reducing power increased with increasing concentration and remains higher than that of vitamin C at the same concentration.Conclusion The extraction process is stable and reliable,and can be used for the extraction of polyphenols and total flavonoids from Plantago ovata Forssk.The ethanol extract of Plantago ovata Forssk exhibits good antioxidant activity.