【摘要】 以双低菜籽饼粕蛋白为原料,以常规酶解为对照,以酶解产物的抑制活性为指标,分别考察了超声预处理蛋白酶、超声预处理蛋白原料和酶解过程前期施加超声3种超声处理方式对双低菜籽蛋白酶解制备ACEI活性肽效果的影响。结果表明,3种超声辅助方式都能有效地促进菜籽饼粕蛋白的酶解,提高产物的ACE抑制活性,其中超声预处理蛋白原料效果最为明显。这种方式的最佳参数为:超声频率20kHz、超声时间30min、超声功率1250W、作用时间4s、间歇时间2s,该条件下酶解产物对ACE的抑制率从对照组的70.83%提高到92.97%,肽得率从29.6%提高到41.4%,半抑制浓度IC50从3.57mg/mL降到2.48mg/mL。这表明脉冲超声辅助酶解法是一种高效制备双低菜籽ACEI肽的方法。更多还原

【Abstract】 Angiotensin-Converting Enzyme Inhibitor(ACEI)peptides were prepared from double-low rapeseed protein by pulsed ultrasonic-assisted enzymolysis.Three reaction models,which included ultrasonic pretreatment of proteinase followed by enzymolysis (UPPE),ultrasonic pretreatment of double-low rapeseed protein solution followed by enzymolysis(UPRPE)and ultrasonic-assisted enzymolysis processes during previous period(UAE),were investigated.The inhibitory activity of hydrolysate to Angiotensin-Converting Enzyme(ACE)was the index.Traditional enzymatic hydrolysis(TE)without ultrasonic treatment was conducted as a control test.Results showed that three models all had significant effects,and UPRPE was the best.The optimum parameters of UPRPE obtained by orthogonal experiments were:ultrasonic frequency 20 kHz,ultrasonic treatment time 30 min,ultrasonic power 1250 W,on-time of the pulse 4 s and off-time 2 s.Compared with the traditional enzymatic hydrolysis,the inhibitory activity of the hydrolysate to ACE increased from 70.83%to 92.97%,ACEI peptide output raised from 29.6%to 41.4%and half inhibiting concentration IC50 value decreased from 3.57 mg/mL to 2.48 mg/mL under the optimum UPRPE conditions.These results prov that the pulsed ultrasonic-assisted enzymatic hydrolysis is a highly efficient method for preparing ACEI peptides from double-low rapeseed protein.更多还原