莲子红衣醇提物的抗氧化和抗褐变活性

Antioxidant and Anti-browning Activities of Ethanol Extract from Lotus Seed Skin

为深入探索莲子加工副产物红衣粉的应用价值,采用清除ABTS+.能力、抑制蘑菇酪氨酸酶单酚酶和二酚酶活性能力、抗苹果褐变能力指标,综合评价莲子红衣醇提物的抗氧化和抗褐变活性,并测定其总酚和总黄酮含量。结果表明:莲子红衣醇提取物的总酚含量为(233.63±10.16)mg/g,总黄酮含量为(166.02±7.31)mg/g;其清除ABTS+.的IC50为(1.385±0.210)mg/mL;在对蘑菇酪氨酸酶活性的抑制实验中,对单酚酶和二酚酶活性的IC50分别为(1.665±0.137)mg/mL和(3.777±0.294)mg/mL;在鲜切苹果褐变模型中,通过分析L*、a*和b*指数的变化,莲子红衣醇提物表现出了较好的抗褐变性能,尤其当醇提物与0.5g/100mL抗坏血酸组合使用时,其抗褐变效果最佳。

The goal of the present work was to evaluate the antioxidant and anti-browning activities of ethanol extract from lotus seed skin. The ABTS＋ radical scavenging activity, anti-tyrosinase activity and anti-browning effect as well as the contents of total phenols and total flavonoids of the extract were determined. The results revealed that the ethanol extract contained （233.63± 10.16） mg/g total phenols and （166.02 ±7.31） mg/g total flavonoids. It also showed a strong antioxidant activity against ABTS free radicals with IC50 of （1.385 ±0.210） mg/mL. In tyrosinase inhibitory assay, the measured ICs0 values were （1.665 ± 0.137） mg/mL for monophenolase and （3.777 ±0.294） mg/mL for diphenolase, respectively. This extract had a significant anti-browning effect on fresh-cut apple slices as demonstrated by measuring changes in L＊, a＊and b＊ values, and the best efficacy was observed when combined with 0.5 g/100 mL ascorbic acid.