机构地区: 华南理工大学食品与生物工程学院
出 处: 《中国乳品工业》 2002年第6期11-14,共4页
摘 要: 采用SDS-PAGE分析,研究了不同条件下微生物转谷氨酰胺酶(MTGase)催化乳清蛋白(WPI)聚合。结果显示,MTGase可催化乳清蛋白的β-乳球蛋白(β-LG)和α-乳清蛋白(α-LA)聚合,形成低聚物或生物聚合物,其中β-LG更易受MTGase的催化。当TGase酶浓度一定时(0.5U/mL),TGase催化WPI聚合的最佳底物质量分数范围为2%~4%。对WPI进行加热预处理,同时添加还原剂,可明显提高MTGase对WPI的催化活性。MTGase催化WIP的最适pH值范围约为6.5~7.5。当WPI经预热处理(85℃,15min),同时添加20mmol/L的DTT,TGase催化WPI聚合12h,可使质量分数为92%的β-LG和质量分数为75%的α-LA聚合。 The polymerization of whey protein isolate(WPI)at different conditi ons by microbial transglutaminase(MTGase)was studied using SDS-PAGE.It indicate d that MTGase could polymerize a-Lactoglobulin(a-LG)and á-lactoalbumin( á-LA)of WPI to produce some oligomers of biopolymers,and a-LG was catalyzed easier than á-LA by MTGase.When the enzyme amount of MTGase kept constant(0. 5 U/mL)and with addition of 20 mmol/L DTT,92%a-LG and 75%á-LA of WPI were polymerized by MTGase after 12 h.