促糖基化对香菇蛋白质消化特性及消化产物抗氧化活性的影响

Effects of Pro-glycosylation on Digestion Characteristics and Antioxidant Activity of Digested Products of Lentinula edodes Protein

为探讨促糖基化对香菇(Lentinula edodes)蛋白质消化特性及消化产物抗氧化活性的影响,采用碱溶酸沉法提取子实体蛋白质,并制备糖基化和谷氨酰胺转氨酶(transglutaminase, TGase)促糖基化蛋白质,通过模拟胃肠消化分别测定蛋白质组(C)、糖基化蛋白质组(G)和促糖基化蛋白质组(TG)的蛋白质消化率、水解度、蛋白质消化产物中的游离氨基酸和多肽含量,以及蛋白质消化产物的DPPH自由基清除率、超氧阴离子自由基清除率、羟基自由基清除率和总抗氧化能力。结果表明:与C组相比,G组在模拟消化90、120、180、240、270min时和TG组在模拟消化90、120、210、240、270min时消化率显著降低,且G与TG组间无显著性差异;在模拟消化60 min时G组水解度显著增加,在90~360 min时显著降低,TG组在模拟消化30、60、150~240、300 min时显著增加,且在模拟消化60~360 min时显著高于G组;G组在模拟消化60、210~360 min时和TG组在模拟消化0、60~360 min时游离氨基酸含量显著增加,且在模拟消化0、120、300~360 min时TG组显著高于G组;在模拟消化所有时间点,G组和TG组多肽含量均显著降低,且在模拟消化0、300~360 min时TG组显著高于G组;在模拟消化所有时间点,G组DPPH自由基清除率均显著增加,且TG组在模拟消化0、150、210~360 min时显著增加,但在模拟消化120、150、180、330、360 min时TG组显著低于G组;G组在模拟消化240~360 min时和TG组在模拟消化330、360 min时超氧阴离子清除率显著增加,且在模拟消化270min时,TG组显著低于G组;在模拟消化所有时间点,G组和TG组羟基自由基清除率和总抗氧化能力均显著增加;但在模拟消化0~180、240 min时TG组羟基自由基清除率显著高于G组,在模拟消化0~180、240~360 min时TG组总抗氧化能力显著低于G组。

The effects of pro-glycosylation on digestion characteristics and antioxidant activity of digested products of Lentinula edodes proteins were studied.Proteins were first extracted from fruiting bodies by the alkali dissolution and acid precipitation method,and then glycosylated(G)by glucose and pro-glycosylated(TG)by transglutaminase+glucose,respectively.Proteins without any treatment were the control(C).Through simulated gastrointestinal digestion,C,G,TG were measured for digestibility and hydrolysis degree.The digested products from different groups were measured for free amino acid and peptide contents,DPPH radical scavenging rate,superoxide anion radical scavenging rate,hydroxyl radical scavenging rate,and total antioxidant capacity.The results showed that there was no significant difference between G and TG in digestibility during the course of the simulated digestion.However,their digestibility was significantly lower than that of C at 90,120,240 and 270 min.Compared with C,the hydrolysis degree of G was significantly increased at 60 min of the simulated digestion,and significantly decreased at 90–360 min.The hydrolysis degree of TG was significantly higher than that of C at 30,60,150–240,300 min,and significantly higher than that of G at 60–360 min.The free amino acid content of TG was significantly higher than that of C at 0 and 60–360 min,and significantly higher than that of G at 0,120,300–360 min.The free amino acid content of G was significantly higher than that of C at 60 and 210–360 min.During the entire course of the simulated digestion,the peptide content of G and TG was significantly lower than that of C.At 0 and 300–360 min,the peptide content of TG was significantly higher than that of G.The DPPH scavenging rate of G was significantly higher than that of C during the entire course of the simulated digestion,and also significantly higher than that of TG at 120,150,180,330,360 min.TG also showed a higher DPPH scavenging rate than C at 0,150,210–360 min.The superoxide anion scavenging rate of G at 240–360 min and that of TG at 330 and 360 min were significantly higher than that of C during the simulated intestinal digestion(180–360 min),and the superoxide anion rate of G was also significantly higher than that of TG at 270 min.For hydroxyl radical scavenging rate,both G and TG showed a significantly higher rate than C at all time points of the simulated digestion.The hydroxyl radical scavenging rate of TG was also significantly higher than that of G at 0–180 and 240 min.Both G and TG had stronger total antioxidant capacity than C in the simulated digestion,and G also showed stronger total antioxidant capacity than TG at 0–180 and 240–360 min.