大鳍鳠蛋白酶活力的研究

Protease activity of digestive tract in Mystus macopterus

以嘉陵江野生大鳍(Mystusmacropterus)为材料,对其蛋白酶的酶活力影响因素、酶解动力学、体外消化率进行综合研究。结果表明,(1)大鳍胃、肠、肝胰脏的蛋白酶最适温度分别为36、40、40℃,最适pH分别为2 2、7 0、7 0,温度对胃、肠蛋白酶的影响大于肝胰脏,pH对胃蛋白酶的影响大于肠和肝胰脏;(2)肠蛋白酶的酶解能力最强,对鱼粉和豆粕酶解产生氨基酸,速度分别为52 288mg/h和33 352mg/h,胃、肝胰脏蛋白酶的酶解能力差异不显著,对鱼粉和豆粕酶解产生氨基酸,速度分别为24 328mg/h、25 275mg/h和19 843mg/h、17 535mg/h;(3)大鳍蛋白酶对鱼粉或豆粕的干物质或粗蛋白消化率均以胃最大,肠次之,肝胰脏最小;鱼粉的体外消化率均大于豆粕的体外消化率。从总体消化能力来看,大鳍蛋白酶对鱼粉和豆粕都有较强的消化能力。

An experiment was conducted on protease activities, kinetics of enzymolysis and digestibility in vitro of Mystus macopterus. The results of protease activities show that the optimum temperatures in stomach, intestine and hepatopancreas for protease are 36, 40 and 40, and the optimum pHs are 22, 70 and 70, respectively Using fishmeal and soybean meal as the feeds to study the kinetics of enzymolysis and the results indicate that the enzymolysis on intestine is better than those in stomach and hepatopancreas that the aminoacidsproducing rate for fishmeal is 52288 mg/h and for soybean meal is 33352 mg/h in intestine, but for enzymolysis in stomach and hepatopancreas there is no significant difference between them