不同干燥预处理对牛蒡多酚和多糖抗氧化活性的影响

Effects of Different Drying Pretreatment on Antioxidant of Arctium lappa L.Polyphenols and Polysaccharides

分别采用自然晾干(AD)、鼓风干燥(HAD)、远红外干燥(FID)、冷冻干燥(FVD)、微波真空干燥(MVD)对牛蒡进行预处理,采用闪式提取制备牛蒡多酚和多糖,以体外抗氧化能力为指标,探讨不同干燥预处理方法对牛蒡多酚和多糖抗氧化活性的影响。结果表明,经不同干燥预处理后牛蒡多酚的提取率和抗氧化活性略有不同,其中FVD的提取率最高,所得多酚具有最佳的DPPH·清除能力和总还原力,IC_(50)值分别为63.73μg/m L和3.79 mg/m L;而MVD的·OH清除能力最优,其IC_(50)值为69.31μg/m L。对于牛蒡多糖,经FVD的提取率最高,但与其他处理的无显著差异;其DPPH·、·OH清除率和总还原力都最佳,IC_(50)分别为0.98,2.21,2.20 mg/m L。结果表明,不同干燥预处理会影响牛蒡多酚和多糖的提取率和抗氧化能力,相比较而言,FVD对牛蒡多糖和多酚的影响最小。

Arctium lappa L.was pretreated by air drying(AD),hot air drying(HAD),far infrared drying(FID),freeze vacuum drying(FVD)and microwave vacuum drying(MVD),Arctium lappa L.polyphenols and polysaccharides were prepared by flash extraction,and the in vitro antioxidant capacity were used as the index to investigated the effects of different drying pretreatment methods on the antioxidant activities of Arctium lappa L.polyphenols and polysaccharides.The results showed that the extraction rate and antioxidant activity of Arctium lappa L.polyphenols after different drying pretreatment were slightly different,among which FVD had the highest extraction rate,with the best DPPH·scavenging ability and total reducing power,IC_(50)values were 63.73μg/m L and 3.79 mg/m L,respectively.Meanwhile,the MVD had the best·OH scavenging capacity,IC_(50)value is 69.31μg/m L.Moreover,the extraction rate of Arctium lappa L.polysaccharide by FVD was the highest,but there was no significant difference with other treatments.The DPPH·,·OH clearance and total reducing power were the best,and the IC_(50)were 0.98,2.21,2.20 mg/m L,respectively.The results showed that different drying pretreatment would affect the extraction rate and antioxidant capacity of Arctium lappa L.polyphenols and polysaccharides.In comparison,FVD had the least effect on Arctium lappa L.polysaccharides and polyphenols.