响应面法优化新疆若羌大枣总黄酮提取工艺及抗氧化活性

Total Flavonoids from Xinjiang Ruoqiang Jujubes: Optimization of Extraction Conditions Using Response Surface Methodology and Antioxidant Activity

在单因素试验基础上,以乙醇体积分数、提取温度、料液比为自变量,进行三因素三水平Box-Behnken试验设计,利用响应面分析法优化新疆若羌大枣总黄酮提取条件;将粗提物进一步分级萃取并对其抗氧化部位进行考察。结合实际可操作性得出大枣中总黄酮较优提取工艺为乙醇体积分数45%、提取温度90℃、料液比1:35(g/mL)、提取时间90min,总黄酮提取量为14.34mg山奈酚/g,达到预测值(14.647mg山奈酚/g)的97.9%。乙酸乙酯萃取物具有显著的抗氧化活性,与抗氧化剂BHT活性相当。

This study was undertaken to optimize condition for the extraction of total flavonoids from Xinjiang Ruoqiang jujubes.One-factor-at-a-time method was used to investigate the effects of ethanol concentration,temperature,extraction time and solid-to-solvent ratio on the extraction yield of total flavonoids.Maximum extraction yield of total flavonoids was reached after 90 min of extraction.Using a three-variable,three-level Box-Behnken experimental design coupled with response surface methodology,ethanol concentration,temperature and solid-to-solvent ratio were optimized to be 45%,90 ℃ and 1：35（g/mL）,respectively.Under the optimized conditions,the actual extraction yield of total flavonoids was 14.34 mg kaempferol equivalent/g,which was 97.9% as compared to the predicted value（14.647 mg kaempferol equivalent/g）.The obtained extract had an ethyl acetate fraction that revealed potent antioxidant activity and was comparable to BHT.