蓝园鲹深度水解过程中蛋白质降解研究

利用风味蛋白酶深度酶解蓝园鲹蛋白，通过比较酶解液的水解度曲线和蛋白质利用率曲线之间的差异、对TCA不溶性氮的变化趋势以及不同酶解时间的凝胶过滤图谱进行分析，探讨了深度酶解过程中蛋白质的降解。酶解6h后大部分蛋白质在酶的作用下降解为水溶性多肽，蛋白质利用率达到83。3％；6h以后蛋白质利用率增长速度降低，这可能是由于可被降解的底物含量降低。此后。风味蛋白酶以水溶性多肽为底物将其进一步降解为小分子肽和氨基酸；21h时水解度达到59．7％。21h以后水解度增长速度降低．这可能是由于亮氨酸氨肽酶难于分解氨基末端上带有甘氨酸和酸性氨基酸的肽。21h以后酶解的主要底物分子量范围在6214到10700的多肽。

Protein degradation of extensive enzymatic hydrolysis of decapterus maruadsi

Experiments were conducted to examine the protein degradation during the extensive hydrolysis of Decapterusmaruadsi by Flavourzyme,using nitrogen recovery,degree of hydrolysis(DH),TCA insoluble nitrogen and gel filtrationchromatography.Results showed that most of TCA insoluble protein was soluble in water after 6 h of hydrolysis,with83.26% nitrogen recovery and 41.8% DH.Prolonging the hydrolysis reaction after 6 h did not result in obvious increase inthe nitrogen recovery,due to the decrease in the substrates available.The DH increased progressively from 41.8% to59.7% until 21 hours.Prolonging the reaction after 21 h resulted only in a minimal increase in the DH.The mainsubstrates for proteolytic hydrolysis after 21 h of extensive hydrolysis were identified as peptides with molecular weightrange from 6214 to 10700 D.