响应面优化微波辅助提取黑莓果渣黄酮及其生物活性研究

Optimization on microwave extraction of flavonoids from blackberry pomaces using response surface methodology and its biological activity

目的采用微波辅助提取黑莓果渣中的黄酮并研究其生物活性。方法通过单因素实验考察微波时间、微波功率、液料比和乙醇浓度4个因素对黑莓果渣黄酮提取率的影响,并通过响应面设计优化黄酮提取条件,确定最佳提取工艺。以铁还原力、清除2,2’-联氨-双-(3-乙基苯并噻唑啉-6-磺酸)二胺盐[2,2’-hydrazine-bis-(3-ethylbenzothiazolin-6-sulfonic acid) diamine salt,ABTS]能力和清除超氧阴离子(O2-·)能力来评价抗氧化能力,以胰脂肪酶抑制率来评价其降血脂能力。结果黑莓果渣黄酮最佳提取工艺条件为微波功率300 W,微波时间8 min,微波温度55℃,乙醇浓度60%,料液比1:20 (g:mL),在此条件下黑莓果渣黄酮最高提取率为15.45 mg/g。黑莓果渣黄酮具有较强的抗氧化活性和降血脂能力,铁还原力、清除ABTS自由基能力、清除O2-·能力及胰脂肪酶抑制率均表现出一定的质量浓度依赖性,其半数有效质量浓度(half effective mass concentration,EC50)分别为0.472、0.620、0.545和10.674 g/L。结论微波辅助可以高效提取黑莓果渣黄酮,黑莓果渣黄酮可作为一种天然的食源性抗氧化和降血脂添加剂。

Objective To extract flavonoids from blackberry pomaces by microwave-assisted and study its biological activity. Methods The effects of microwave time, microwave power, liquid-solid ratio and ethanol concentration on the extraction rate of flavonoids from blackberry pomace were studied by single factor experiment. The extraction conditions were optimized by response surface methodology to determine the optimal extraction process. The antioxidant capacity was evaluated based on iron reduction ability, 2,2’-hydrazine-bis-(3-ethylbenzothiazolin-6-sulfonic acid) diamine salt(ABTS) and superoxide anion(O2-·) removal ability, and the hypolipidemic activity was evaluated based on pancreatic lipase inhibition rate. Results The optimal extraction conditions of flavonoids from blackberry pomaces were as follows: Microwave power 300 W, microwave time 8 min, microwave temperature 55 ℃, ethanol concentration 60% and solid-liquid ratio 1:20(g:mL). Under these conditions, the highest extraction rate of flavonoids from blackberry pomace was 15.45 mg/g. The flavonoids from blackberry pomaces had strong antioxidant activity and hypolipidemic activity. The ability of reducing iron, removing ABTS free radicals, O2-· and the inhibition rate of pancreatic lipase showed a certain concentration dependence. The EC50(half effective mass concentration) values were 0.472, 0.620, 0.545 and 10.674 g/L, respectively. Conclusion Microwave-assisted extraction of flavonoids from blackberry pomace is highly efficient, and blackberry pomace flavonoids can be used as a natural food-borne antioxidant and hypolipidemic additive.