黑鱾（Girellaleonina）淀粉酶与蛋白酶的活力研究

通过测定1＋龄黑鱾的胃、盲囊、肝脏和肠道4个消化组织中蛋白酶和淀粉酶活性，并研究其与温度及pH值的关系，可以为黑纪的合理投饵提供理论依据．实验设9个温度梯度（10～50℃）和14个pH缓冲液梯度（pH2．0～9．0），用淀粉-碘显色法测淀粉酶活力，用福林-酚试剂法测蛋白酶活力．结果表明：黑纪盲囊、肠道中淀粉酶和蛋白酶活力均较高，最适温度为35℃，淀粉酶最高活力为每克鲜组织46．02U和42．61U蛋白酶最高活力为每克鲜组织156．52u和147．79U；胃中酶的最适温度为40℃，肝脏中淀粉酶温度要求稍低，最适温度为30℃，酶活力值也最低；胃淀粉酶和胃蛋白酶最适pH值分别为6．5和3．5，盲囊、肠道和肝脏组织中的最适pH值相近，为7．0-8．0．可以认为黑鲍胃中主要存在着酸性蛋白酶，胃是食物蛋白质初步分解消化的场所；Q10值充分反映了温度对消化酶活力的影响，当温度从10℃上升至20℃时。2种消化酶活力增幅显著，可作为开始投饵的温度指标．

Study on Activities of Amylase and Protease of Girella leonina

This paper measures amylase and protease in the four digestive organ of Girella leonina to find how digestive enzyme activity changes given different temperature and pH value. Nine temperature gradient （10-50 ℃） and 14 pH gradient buffer （pH 2.0-9.0） are set up in the experiment conducted in this research using starch- iodine chromogenic method for amylase activity and Folin-phenol reagent method for protease. The results show that the optimal temperature for both amylase of diverticulum and intestine is 35 ℃, their maximal dynamic value of amylase accounts for 46.02 U·g^-1fresh organizations and 42.61 U.g^-1 fresh Organization, respectively. For protease, the value are 156.52 U·g^-1 fresh organizations and 147.79 U·g^-1 fresh Organization, respectively. Stomach enzyme optimum temperature is found to be 40℃, and liver amylase optimum temperature requirements is noted for being slightly lower than 30℃, which reaches the lowest value of enzyme activity. The optimum pH values for stomach are 6.5 and 3.5, whereas the optimum pH value for diverticulum, intestine and liver tissue turns out to be close to 7.0-8.0. As a result, acid protease is the major protease in stomach, stomach is also the initial decomposition place for digestion. The value of Q10 reflects the influence of temperature on the digestive enzyme activity, so the temperature indicators should be counted as the beginning of feeding.