鲤鱼肠道细菌及其淀粉酶对宿主消化的影响

THE INFLUENCES OF COMMON CARP INTESTINAL BACTERIA AND ITS AMYLASES ON THE HOST DIGESTION

本文就鲤鱼肠道细菌对其宿主的影响和细菌淀粉酶对宿主消化的影响作了探讨。从鲤鱼肠道筛选细菌菌株６３株，这批细菌中淀粉酶产生菌分布较广，溶血毒素产生菌较少，且产毒素的６株菌无致病性。淀粉酶活力较高的ＣＣＩ１３９菌株的淀粉酶和鲤鱼肝胰脏淀粉酶的最适ｐＨ和反应产物都不相同。原位酶反应法显示鲤鱼肠道食物混合液及肠壁样品中均有细菌淀粉酶。本文结果证明了鲤鱼肠道有稳定的细菌群落，细菌淀粉酶对鲤鱼消化食物中的淀粉起了促进作用。

This paper deals with the influence of intestinal bacteria on common carp (Cyprinus carpio) and bacterial amylases on the host digestion. Sixty three strains of bacteria have been isolated from carp intestines and intestinal foods in this connection. The distribution of amylase and hemolysin producing strains among the intestinal bacteria has also been investigated. The distribution of amylase producing strains is broad, while that of hemolysin is narrow, and these hemolysin producing strains are not lethal to fish. These results indicate that there were no pathogens among the intestinal bacteria obtained in this experiment. Furthermore,the carp amylase had an apparent optimal PH of 7.6 and worked well between 7.2 to 8.0.The CCI 139 (one strain whose production of amylase was higher than that of other strains) amylase had an apparellt optimal pH of 8. 8 and worked well between 8.4 to 9.4,while the pH of instestinal mixture ranged from 6.0--7.0. Finally,the in situ reaction of amylases after SDS-PAGE has convinced that there were bacterial amylases in carp intestinal mixture. The results mentioned above show that there are stable microflora in common carp intestines and bacterial amylases play a promoting effect on starch digestion by host.