丁香不同提取方法提取物的抗氧化活性

Antioxidant Activity of Clove Extracts by Different Extraction Methods

采用微波辅助提取、超声辅助提取和索氏提取3种方法对丁香非挥发性成分进行提取,通过对比单因素实验下不同提取方式得到的总黄酮、总酚含量和抗氧化能力,并结合扫描电镜下丁香粉末的微观结构,选择最佳提取方式;再通过响应面实验优化提取工艺。结果表明,微波辅助提取为最佳提取方式,最优提取工艺条件为微波功率248 W,提取温度52℃,乙醇体积分数72%,提取时间23.5 min,在该条件下总黄酮含量为30.96%±0.44%（309.62±4.41 mg/g）,总酚含量70.13%±0.86%（701.34±8.64 mg/g）,与预测值相符。DPPH自由基清除能力为99.67%±0.32%、ABTS自由基清除能力为99.81%±0.22%、铁离子还原能力为4.01±0.16 mmol/L、Fe^2＋螯合能力为30.73%±0.92%、抗脂质过氧化能力为83.44%±1.27%,丁香非挥发性成分提取物具有较好的抗氧化能力。

The non-volatile components of clove were extracted by microwave-assisted extraction （ MAE ）, ultrasonic-assisted extraction （UAE） and Soxhlet extraction （ SE ）. The total flavonoids content （TFC）, total phenol content （TPC） and antioxidant capacity were compared by single factor experiments. Meanwhile, the microstructure of clove powder was observed by scanning electron microscope（SEM）. On the basis of single factor experiments, the response surface methodology was designed to optimize the extraction process. The results showed that the microwave-assisted extraction was the best method. The optimal conditions of MAE were microwave power 248 W, extraction temperature 52 ℃, ethanol （ volume fraction） 72%, and extraction time 23.5 rain. Under the above conditions,the content of total flavonoids was 30.96%±0. 44% （309.62±4. 41 rag/g） and that of total phenols was 70. 13% ±0. 86% （701.34 ±8.64 mg/g） ,which were consistent with the predictive values. The DPPH-scavenging activity was 99.67%± 0.32%, the ABTS-scavenging activity was 99. 81% ±0. 22% ,the ferric reducing antioxidant power was 4. 01 ±0. 16 mmol/L,the Fe2＋ chelating capacity was 30.73%± 0. 92%, and the anti-lipid peroxidation activity was 83.44% ± 1.27%. The results revealed that the non-volatile components of clove had excellent antioxidant activities.