鳜鱼、青鱼、草鱼、鲤、鲫、鲢消化酶活性的研究

STUDIES ON THE ACTIVITY OF DIGESTIVE ENZYMES IN MANDARIN FISH, BLACK CARP,GRASS CARP, COMMON CARP, CRUSIAN CARP AND AILVER CARP

鳜鱼、青鱼、草鱼、鲤、鲫、鲢肝脏蛋白酶活性低于肠蛋白酶。肠蛋白酶活性，鳜鱼最高，其余依次为青鱼、鲤、鲢、草鱼、鲫。鳜鱼、鲢的肠蛋白酶活性由前肠向后肠递减；而青鱼、鲤、草鱼的则由前肠向后肠递增；鲫则中肠活性最低。六种鱼不同组织的脂肪酶活性因鱼而异。青鱼、鳜鱼、鲤、鲢肝脏中脂肪酶活性低于肠脂肪酶活性（Ｐ＜０．０１）；而草鱼和鲫肝脏中脂肪酶活性与肠脂肪酶活性差异不明显（Ｐ＞０．０５）。六种鱼肝脏中脂肪酶活性由高到低依次为鳜鱼＞鲢＞鲫＞草鱼＞青鱼＞鲤；肠脂肪酶活性顺序为鳜鱼＞鲢＞青鱼＞鲤＞草鱼＞鲫。脂肪酶活性与鱼类食性无明显相关性。不同组织间淀粉酶活性存在差异。鳜鱼的肝脏和肠均有较高淀粉酶活性，青鱼和鲫肝脏中淀粉酶活性低于肠中的；草鱼、鲤和鲢肝脏中淀粉酶活性高于肠中的，但差异不显著。六种鱼中鳜鱼的肝脏淀粉酶活性明显高于其它五种无胃鱼，它们的淀粉酶活性顺序依次为鳜鱼＞鲢＞鲤＞草鱼＞青鱼＞鲫；肠淀粉酶活性顺序为鳜鱼＞鲫＞鲤＞青鱼＞鲢＞草鱼。

The protease activity inliver of mandarin fish(Siniperca chautsi),black carp(Mylopharyngodon piceus),grass carp(Ctenopharyngodon idellus),common carp(Cyprinus carpio), crucian carp(Carassius auratus ) and silver carp(Hypopthalmichthysmolitrix) were lower than that in their intestine, Among the six species , the proteaseactivity in intestine ranged from high to low : mandarin fish, black carp, common carp,silver carp, grass carp and crucian carp. The protease activity were decreasing gradually inintestine from proximal to distal in mandarin fish and silver carp;however, in black carp and grass carp the results were opposite , in crucian carp the lowest was in middle gut. The lipase activity in various tissue were different with the species. The lipase activityin liver in black carp , mandarin fish , common carp , silver carp were lower than that in theirintestine (P<0. 01). In grass carp and crucian carp , there was no significant difference oflipase activity between in liver and in intestine(P>0. 05). Theorder of lipase activity fromhigh to low in liver was mandarin fish> silver carp> crucian carp> grass carp> black carp>common carp , and that in intestine was mandarin fish > silver carp > black carp >common carp > grass carp > crucian carp. The result showed that the lipase activity wasnot significantly relative to the food habit. Amylase activity between tissues was different and changes with species, The amylaseactivity in liver and intestine in mandarin fish were all high. The amylase activity in liver inblack carp and crucian carp were lower than that in intestine , however, in grass carp,common carp , silver carp , the results were opposite , but their difference was notsignificant. The order of amylase activity from high to low in liver was mandarin fish >silver carp> common carp> grass carp> black carp> crucian carp , and that in intestinewas mandarin fish> crucian carp> common carp> black carp> silver carp>grass carp.