不同干燥方法对金针菇多糖抗氧化活性的影响

Effect of different drying methods on antioxidant activities of polysaccharides extracted from Flammulina velutipes

以金针菇为原料,利用传统水提法提取金针菇多糖(polysaccharides from Flammulina velutipes,FVP),分别对传统热风干燥多糖(FVP-H)、真空干燥多糖(FVP-V)和冷冻干燥多糖(FVP-F)的成分和抗氧化活性进行研究。结果表明,FVP为酸性多糖,不同干燥方法对其单糖种类没有影响,但会改变单糖的构成比例和糖醛酸含量,FVP-H、FVP-V和FVP-F相对分子质量变化不明显,分别为2342309、2375843和2358437 Da。FVP-H、FVP-V和FVP-F具有较强的清除DPPH自由基、羟基自由基、超氧阴离子自由基的能力和还原力,在一定浓度范围内,多糖与抗氧化活性及还原能力之间呈正相关关系,干燥方法对FVP抗氧化活性具有不同的影响,其中FVP-F抗氧化活性最强,其次是FVP-V和FVP-H,冷冻干燥是制备FVP适宜的干燥方法。

Flammulina velutipes was used as raw materials. Polysaccharides from Flammulina velutipes（ FVP） were extracted using conventional water extraction.FVP-H,FVP-V and FVP-F were obtained with hot-air drying,vacuum drying and freeze drying,respectively.Component and antioxidant activities of FVP-H,FVP-V and FVP-F were investigated.The results showed that FVP were acidic polysaccharides.Different drying methods had no effect on the monosaccharide species. However,it could change the monosaccharide composition and uronic acid content.The relative molecular weight of FVP-H,FVP-V and FVP-F were not obvious,which were 2342309,2375843 and 2358437 Da,respectively. FVP-H,FVP-V and FVP-F had a stronger scavenging ability of DPPH radical,hydroxyl radical,superoxide anion free radical and reducing power. In a certain concentration range,FVP were positively correlated with the antioxidant activity and reducing capacity.Different drying methods had different effects on the antioxidant activity of FVP. FVP-F had highest antioxidant activities,followed by FVP-V and FVP-H. Freeze-drying was the best drying method for preparation of FVP.