In this study,with Vigna umbellata as the raw material,intracellular polysaccharides are extracted from Vigna umbellata by ultrasonic-assisted enzymatic method and water extraction and ethanol precipitation technology.The extraction technology is optimized,and the polysaccharides are modified through ultrasonic wave.In order to expand the application fields,the antioxidant properties of intracellular polysaccharides from Vigna umbellata and their refrigerated preservation effects on fruits and vegetables before and after modification are studied.The results show that the optimal technology conditions for the extraction of polysaccharides from Vigna umbellata are ultrasonic time of 50 min,water extraction temperature of 70 ℃,water extraction time of 200 min and compound enzyme treatment temperature of 47 ℃.Under such conditions,the extraction rate of polysaccharides is 4.33％.The results of antioxidation test in vitro show that the scavenging rates of modified Vigna umbellata polysaccharides on·OH,DPPH·,ABTS+·are 88.35％,83.67％,58.82％respectively,which are 18.1％,17.4％,14.87％higher than those before modification respectively.The results of cold storage preservation test of polysaccharides on strawberries before and after modification show that the order of their preservation ability is 3％modified Vigna umbellata polysaccharides group＞1％modified Vigna umbellata polysaccharides group＞3％Vigna umbellata polysaccharides group＞1％Vigna umbellata polysaccharides group.Therefore,the extraction rate of Vigna umbellata polysaccharides is relatively high by using the extraction technology in this study,and the free radical scavenging rates of modified polysaccharides are significantly higher than those before modification.The Vigna umbellata polysaccharides before and after modification both have preservation effect on strawberries,and the preservation effect of modified Vigna umbellata polysaccharides is better than that before modification.
关键词
多糖/赤小豆/提取工艺/抗氧化活性/果蔬保鲜
Key words
polysaccharides/Vigna umbellata/extraction technology/antioxidant activity/preservation of fruits and vegetables
维普
万方数据