不同溶剂提取穇子多酚的抗氧化性及对龙眼保鲜作用的研究

Antioxidant of Finger Millet Polyphenols Extracted from Different Solvents and Its Preservation Effect on Longan

采用乙醇、甲醇、酸性乙醇和酸性甲醇提取穇子多酚,并对其抗氧化性和保鲜作用进行了研究。结果表明:穇子多酚消除DPPH自由基的能力大于BHT接近VC;还原能力接近BHT与VC;低浓度条件下对羟基自由基的清除能力均低于BHT与VC,高浓度时则接近BHT。经过穇子多酚处理的龙眼果实在可滴定酸含量方面优于茶多酚和VC处理组,在失重率、腐烂率、VC含量、还原糖和总糖含量方面接近于茶多酚和VC。整体而言,穇子多酚都表现出较好的抗氧化活性和保鲜作用,其中以酸性乙醇提取的效果最好。穇子多酚可作为天然保鲜剂进行进一步开发与利用。

In this paper,ethanol,methanol,acidic ethanol and acidic methanol were used to extract finger millet polyphenols,of which the antioxidant and fresh-keeping effects were studied.The results showed that the ability of finger millet polyphenols to eliminate DPPH free radicals was greater than that of BHT and was close to that of VC;the reducing ability was close to BHT and VC;the ability to scavenge hydroxyl radicals at low concentrations was lower than that of BHT and VC,and at high concentrations it was close to BHT.Longan fruit treated with finger millet polyphenols was superior to tea polyphenols and VC treatment groups in weight loss rate and titratable acid content,and was close to tea polyphenols and VC in rotting rate,VC content,reducing sugar and total sugar content.On the whole,finger millet polyphenols showed good antioxidant activity and freshness preservation,and the extraction with acidic ethanol was the best.It can be used as a natural preservative for further development and utilization.