鱼腥草根总黄酮超声辅助酶法提取工艺优化及其抗氧化活性研究

为优化超声辅助酶法提取鱼腥草根总黄酮的工艺，以黄酮提取量为指标，通过单因素实验筛选出适宜的液料比、粒径、乙醇浓度、酶解时间、加酶量，通过Box-Behnken响应面优化鱼腥草黄酮提取最佳条件，并对黄酮抗氧化活性进行研究。结果表明，最佳提取工艺为液料比28:1 mL/g、粒径<250μm、乙醇浓度54%、酶解时间22 min，在该条件鱼腥草黄酮提取量为22.197 mg/g，产品干燥后纯度为26.63%。所得鱼腥草黄酮对DPPH·、·OH、ABTS⁺·有良好的清除能力，EC₅₀值分别为0.097、2.250、0.384 mg/mL。本研究为鱼腥草根总黄酮提取提供了理论依据，为进一步实现鱼腥草资源的高值化利用提供了参考。

Ultrasonic Assisted Extraction Process of Flavonoids from Houttuynia cordata Thunb and Its Antioxidant Activity

To optimize the process of ultrasound-assisted enzymatic extraction of total flavonoids from the roots of Houttuynia cordata, the appropriate liquid to material ratio, particle size, ethanol concentration, enzymatic digestion time, and enzyme addition was screened out by single-factor experiments, and the optimal conditions for the extraction of the flavonoids from Houttuynia cordata were optimized by Box-Behnken response surface. Meanwhile, the antioxidant activity of flavonoids was investigated. The results showed that the optimum extraction process was liquid to material ratio of 28:1 mL/g, particle size of <250 μm, ethanol concentration of 54%, and enzymatic digestion time of 22 min. The extraction amount of flavonoids was 22.197 mg/g under the optimized conditions, and the purity reached 26.63% by concentration under reduced pressure. The obtained flavonoids showed good scavenging ability for DPPH·, ·OH, and ABTS+· with EC₅₀ values of 0.097, 2.250, and 0.384 mg/mL, respectively. The results of the study would provide a theoretical basis for the extraction of total flavonoids from the roots of Houttuynia cordata and a reference for further realization of the utilization of Houttuynia cordata.