黑菊芋结合酚的提取及其抗氧化活性研究

Study on extraction and antioxidant activity of bound polyphenols from black Helianthus tuberosus

中文关键词:  黑菊芋  结合态多酚  提取工艺  响应面法  抗氧化活性

英文关键词:black Helianthus tuberosus  bound polyphenols  extraction process  response surface methodology  antioxidant activity

中文摘要:

      目的 建立黑菊芋结合态多酚的较优提取工艺, 评价其抗氧化活性。方法 采用碱水解结合乙酸乙酯萃取法, 以液料比、氢氧化钠水解温度和水解时间为单因素, 结合态多酚提取率作为考察指标, 采用响应面法优化黑菊芋结合酚的提取工艺; 采用福林酚法检测黑菊芋中游离酚和结合酚的含量, 并评价其体外抗氧化活性。结果 黑菊芋结合酚的最优提取条件为液料比15:1 (mL/g), 氢氧化钠水解时间为45 min, 水解温度为50 ℃, 经120 mL乙酸乙酯萃取10 min, 此时结合酚的提取率为(34.28±1.36) mg/100 g, 模型预测值为33.69 mg/100 g, 相对误差为1.75%; 黑菊芋中游离酚含量是结合酚的12.21倍, 游离酚和结合酚的体外抗氧化活性与其含量呈正相关。结论 响应面法可用于黑菊芋结合酚提取工艺的分析和预测; 黑菊芋游离酚的体外抗氧化活性略好于结合酚, 但差异不显著(P>0.05)。

英文摘要:

      Objective To establish an optimal extraction process for the bound polyphenols of black Helianthus tuberosus, and evaluate its antioxidant activity. Methods Alkali hydrolysis combined with ethyl acetate extraction method was adopted, the liquid-to-material ratio, sodium hydroxide hydrolysis temperature and hydrolysis time were used as single factors, and the extraction rate of bound polyphenols was used as the investigation index, and the extraction process of black Helianthus tuberosus bound polyphenols was optimized by response surface methodology. Additionally, the folin-ciocalteu method was used to determine the content of free and bound polyphenols and the antioxidant activity in vitro was subsequently evaluated. Results The results suggested that the optimal extraction conditions were as follows: Liquid-to-material ratio 15:1 (mL/g), sodium hydroxide hydrolysis time 45 min, hydrolysis temperature 50 ℃. After extracted with 120 mL ethyl acetate for 10 min, the extraction rate of bound polyphenols was (34.28±1.36) mg/100 g, the predicted value was 33.69 mg/100 g, and the relative error was only 1.75%. The content of free polyphenols in black Helianthus tuberosus was 12.21 times that of bound polyphenols, and its antioxidant activity was correlated with the content of polyphenols. Conclusion The response surface methodology can be used to analyze and predict the extraction process of bound polyphenols from black Helianthus tuberosus. In vitro antioxidant activity of free polyphenols of black Helianthus tuberosus is slightly better than that of bound polyphenols, but the difference is not significant (P>0.05).