超声-酶辅助低共熔溶剂提取桑叶总黄酮的工艺优化及其抗氧化活性研究

Optimization of Ultrasonic-Enzyme-Assisted Deep Eutectic Solvents Extraction Process of Total Flavonoids from Mulberry Leaves and Its Antioxidant Activity

为建立一种绿色高效的桑叶总黄酮提取方法,本研究采用了超声-酶辅助低共熔溶剂法对桑叶总黄酮进行提取。在单因素实验的基础上,以桑叶总黄酮提取量为响应值,采用Box-Behnken响应面法对提取工艺进行优化,并研究桑叶总黄酮对ABTS^(+)和DPPH自由基的清除能力。结果表明:在氯化胆碱/果糖/乙醇摩尔比为1:1:3、含水量为30%、液料比为40 mL/g、超声功率为360 W、超声温度为40℃、超声时间为40 min、酶添加量为4%条件下,桑叶总黄酮提取量为46.58 mg/g;当总黄酮质量浓度为0.08 mg/mL时,对DPPH自由基清除率为98.36%,当总黄酮质量浓度为0.2 mg/mL时,对ABTS+自由基清除率为72.12%。因此,超声-酶辅助低共熔溶剂法可有效提取桑叶总黄酮,该法操作简单,绿色环保,提取率高,为桑叶资源的开发利用提供了科学依据。

This study used ultrasound-enzyme-assisted deep eutectic solvents to establish a green and highly efficient total flavonoids extraction process from mulberry leaves.On the basis of the results of single-factor experiments,the extraction amount of total flavonoids was used as the response value,and the Box-Behnken response surface method was used to optimize,and the antioxidative ability of total flavonoids from mulberry leaves on DPPH radicals and ABTS^(+)radicals was studied.The results showed that when the choline chloride/fructose/alcohol molar ratio was 1:1:3,water content 30%,liquid-solid ratio 40 mL/g,ultrasonic power 360 W,ultrasonic temperature 40℃,ultrasonic time 40 min,dosage of enzyme 4%,the extraction amount of total flavonoids from mulberry leaves reached 46.58 mg/g.When the mass concentration of total flavonoids from mulberry leaves was 0.08 mg/mL,the scavenging rate of DPPH radicals was 98.36%.And when the mass concentration of total flavonoids from mulberry leaves was 0.2 mg/mL,the scavenging rate of ABTS+radicals was 72.12%.Therefore,the ultrasonic-enzyme-assisted deep eutectic solvents method was green and simple to operate,and could effectively improve the extraction yield of total flavonoids from mulberry leaves.This method provided a scientific basis for the development and utilization of mulberry leaf resources.