琥珀酸脱酰胺对小麦面筋蛋白酶解产物抗氧化性的影响

Effect of deamidation with succinic acid on the antioxidant activities of enzymatic hydrolysates of wheat gluten

研究琥珀酸不同脱酰胺程度对小麦面筋蛋白胰酶的酶解产物抗氧化性的影响。在相同水解度下,以DPPH.清除率、.OH清除率、ORAC值为抗氧化指标,结果表明低脱酰胺程度(22.4%)的小麦面筋蛋白酶解产物的抗氧化性有较大幅度的提高,高脱酰胺程度(60.4%)的小麦面筋蛋白酶解产物的抗氧化性降低。水解度15%的酶解产物的肽分子量分布表明,低脱酰胺的小麦面筋蛋白酶解产物中分子量小于3000u的肽段增加,高脱酰胺的小麦面筋蛋白酶解产物中分子量小于3000u的肽段减少;在相同水解度下的氨基酸分析结果表明,脱酰胺后的小麦面筋蛋白酶解生成的肽的疏水性和抗氧化性的氨基酸含量提高。因此,低脱酰胺的小麦面筋蛋白酶解产物抗氧化性提高的主要原因是产物中含疏水性和抗氧化性氨基酸的小分子肽含量提高。

Effects of deamidation with succinic acid on antioxidant activities of pancreatin enzymatic hydrolysates of wheat gluten were studied. Under the same degree of hydrolysis（DH）, DPPH radical scavenging ability,OH radical scavenging ability and ORAC value of hydrolysates were investigated. Results indicated that the antioxidant abilities of hydrolysates of low succinic deamidized wheat gluten （SDG-L） increased ;while the antioxidant abilities of hydrolysates of high succinic deamidized wheat gluten（SDG-H） decreased. Under 15% DH,the amount of peptides with molecule weight lower than 3000u in the SDG-L increased ;while that of in the SDG-H decreased. The hydrophobic amino acids and antioxidative amino acids increased in both SDG-L and SDG-H. Therefore,the increase of low molecular peptides,hydrophobic amino acids and antioxidative amino acids contributed to the improvement of antioxidant activities of SDG-L.