不同干燥方式对淫羊藿黄酮类成分含量及抗氧化活性影响

Effects of different drying methods on flavonoids content and antioxidant activity of Epimedii Folium

目的比较不同干燥方式对淫羊藿黄酮类成分含量及抗氧化活性的影响,优选淫羊藿的最佳干燥方式。方法分别采用冷冻干燥、阴干、微波干燥、炒干、蒸制后阴干以及不同温度(50、75、100、125、150、175、200℃)烘干的方式,制得12个样品。以淫羊藿黄酮类成分含量、醇浸出物含量、指纹图谱中共有峰峰面积与称样量的比值和(比值和)及自由基清除能力为指标进行评价。结果不同干燥方式对5种黄酮朝藿定A、朝藿定B、朝藿定C、淫羊藿苷和宝藿苷I的含量影响较大,微波干燥样品(S10)中5种黄酮总量最高;冷冻干燥样品(S8)的总黄酮含量和醇浸出物含量最高;175℃烘干样品(S6)的比值和最高;以上述4个指标进行综合评分,发现微波干燥样品(S10)的综合得分最高。自由基清除实验表明微波干燥样品(S10)的稀乙醇提取物对DPPH自由基和超氧阴离子自由基的清除能力最强,高温烘干样品(S5~S7)对羟自由基的清除能力较强。结论综合考虑黄酮类成分含量和抗氧化活性,建议淫羊藿最佳的干燥方式为微波干燥,但是微波干燥是否能用于淫羊藿工业生产的干燥步骤,有待进一步研究。

Objective To investigate the effects of different drying methods on the flavonoids content and antioxidant activity of Epimedii Folium(EF), so as to optimize the best drying method for EF. Methods A total of 12 samples were prepared by freezedrying, shade drying, microwave drying, stir-frying, shade drying after steaming and drying at different temperatures(50, 75, 100, 125, 150, 175, and 200 ℃). The flavonoids content, alcohol extract content, the ratio of the total peak area of the fingerprint to the volume of the sample(ratio of sum) and free radical scavenging rate were used as the indexes for detection. Results Drying method had a great influence on the contents of five flavonoids, epimedin A, epimedin B, epimedin C, icariin, and baohuoside I, the microwavedried(S10) sample had the highest contents of five flavonoids. The freeze-dried sample(S8) had the highest contents of total flavonoids and alcohol extracts. The ratio of sum of dried sample at 175 ℃(S6) was the highest. It was found that the microwave-dried sample(S10) had the highest comprehensive score based on the above four indexes. The free radical scavenging experiments showed that microwave-dried sample(S10) had the strongest scavenging ability on DPPH free radical and superoxide anion free radical, while the high-temperature dried sample(S5—S7) had the strongest scavenging ability on hydroxyl free radical. Conclusion Considering the content of flavonoids and antioxidant activity, microwave drying is recommended as the best drying method for EF, but whether microwave drying can be used in the industrial production of EF remains to be further studied.