纤维素酶辅助提取芦笋黄酮及其抗氧化活性分析

Extraction and Antioxidant Activity of Asparagus Flavonoids

以黄酮得率为指标,利用纤维素酶协同乙醇提取法从芦笋中提取黄酮,采用响应面设计优化最佳提取工艺参数。结果表明:当液料比50∶1(mL/g)、酶添加量0.20%、乙醇体积分数38.90%、酶解时间1.50 h、酶解温度50.0℃、pH 5.0时,芦笋黄酮最高得率为3.99%。当样品质量浓度达到100μg/mL时,芦笋黄酮对羟自由基的清除率为46.08%,芦笋黄酮对超氧阴离子自由基的清除率为59.42%。小鼠体外抗氧化实验表明,20μg/mL芦笋黄酮处理组超氧化物歧化酶(SOD)活力提高16.85%,丙二醛(MDA)含量减少2.49%。以D-半乳糖法亚急性衰老小鼠为模型,高剂量组小鼠血清和肝组织液SOD活力分别提高11.69%和27.62%,MDA含量分别减少38.04%和37.95%。

The present study was carried out to obtain the optimal process conditions for extracting the maximum amount of flavonoids from asparagus. For the extraction of flavonoids, dried and powdered asparagus was refluxed with aqueous ethanol following hydrolysis with cellulase. Various process parameters were optimized by response surface methodology. Results indicated that the optimal extraction conditions were enzymatic hydrolysis at an enzyme dose of 0.20% for 1.5 h at pH 5.0 followed by refluxing with 38.90% ethanol at a solvent-to-solid ratio of 50：1 （mL/g）. Under these conditions, the maximum extraction yield of flavonoids from asparagus was 3.99%. The flavonoids extracted from asparagus at the concentration of 100μg/mL were able to scavenge 46.08% hydroxyl radical and 59.42% superoxide anion radical. In vitro antioxidant tests showed that treatment with concentration of 20 μg/mL flavonoids resulted in a 16.85% increase in superoxide dismutase （SOD） activity and a 2.49% reduction in malondialdehyde （MDA） content of mouse serum. SOD activity in serum and liver tissue homogenate supernatant from D-galactose induced mouse aging model was increased by 11.69% and 27.62% as a result of this treatment, and MDA content was reduced by 38.04% and 37.95%, respectively.