糙米发芽前后抗氧化活性比较研究

以超声波-微波辅助乙醇提取法和水提法比较糙米发芽前后总多酚的变化,以滴定法检测糙米发芽前后VC含量的变化,并对多酚提取物消除自由基的能力和对食用油脂的抗氧化作用进行了研究.研究结果表明,用超声波-微波辅助80%乙醇提取法优于水提法,总多酚的提取率提高了1.6倍.糙米经发芽后总多酚质量分数达0.3%,比糙米原料总多酚增加了87.5%;VC发芽前未被检出,发芽后增加到1.048 mg/100 g;发芽糙米清除羟基自由基效果比糙米原料高40%,能有效延缓食用油脂的酸败.

Antioxidant Effect of Germinated Brown Rice

Aiming to study the change of total polyphenols and VC contents of germinated brown rice,the total polyphenols of brown rice and germinated brown rice were xtracted by water or by 80% alcohol assisted with ultrasonic wave-microwave.The ability of eliminating hydroxyl free radical and the antioxidant effect for edible oil of the polyphenols were determined.Results: The polyphenols extracted by 80% alcohol assisted with ultrasonic wave-microwave is superior to that extracted by water,and the polyphenols extraction rate of the former is 1.6 times as high as that of the later.The total polyphenols content of germinated brown rice is 0.3%,higher than that of the original brown rice by 87.5%.The VC content in germinated brown rice is 1.048 mg/100g,while not be detected before germination.The germinated brown rice has good ability of eliminating hydroxyl free radical,higher than the original brown rice by 40% ,and can delay edible oil rancidity effectively.