鲢、鳙蛋白酶、淀粉酶的研究

The protease and amylase of Hypophthalmichthy molitrix and Aristichthys nobilis

运用酶动力学方法研究了鲢、鳙的蛋白酶和淀粉酶的活性分布。鲢、鳙的蛋白酶活性在肝胰脏中最强，脾脏中也较强，而在胆汁中未测出。该酶活性在肠粘膜的第Ⅱ段最大，第Ⅰ段向第Ⅱ段递增，第Ⅱ段向肠后端递减，但第Ⅴ段的该酶活性比前段要高些。鲢的淀粉酶活性分布规律与上述情况相似，但鳙的淀粉酶活性在肠粘膜各段中由前向后呈递减趋势，并以第Ⅰ段为最大。在相同的器官组织中，鳙蛋白酶活性高于鲢，但差异不显著（Ｐ＞０．０５），而淀粉酶活性则相反。这两种鱼的蛋白酶活性适宜ｐＨ为８．０～８．５，淀粉酶活性在ｐＨ７．５时最适。在鲢的肠内容物中发现有纤维素酶活性，但在肠粘膜中未检出该酶。

The activities of protease and amylase of silver carp, Hypophthalmichthy molitrix and bighead carp, Aristichthys nobilis were researched with the method of enzyme kinetics.Protease activity in hepatopancreas was higher than that in any other organs in the 2 species.The protease activity was higher in spleen, but not detected in bile. As for 5-equal sections of the intestine, the biggest activity of protease was in section . The activity increased from intestine section to , and decreased rapidly thereafter,except the activity was higher in section than that in section . The activity distribution of amylase was similar to that above in silver carp, but in bighead carp, the amylase activity decreased from section to,with the bigg est in section .As for the same organ and tissues in both of the 2 species,protease activity in bighead carp were higher than that in silver carp,but was not significantly different between them (P>0.05). The differences of amylase activity between the 2 species were contrary to those of protease activities.Protease activity of the 2 species had an optimum pH ranging from 8.0 to 8.5 and amlase at 7. 5. Cellulase activity was detected in the gut content,but not in the intestinal mucosa in silver carp.