许氏平鮋消化道中部分消化酶的研究

Distribution of intestinal enzymes in digestive tract of Sebastes schlegeli

对许氏平 (Sebastesschlegeli)消化道内的 5种与消化吸收有关的酶进行分布和活性测定。结果表明 ,(1)肠道各段均具很高碱性磷酸酶活性 ,最适 pH为 9.7。食道和胃几乎没有碱性磷酸酶活性。 (2 )消化道各部位均含酸性磷酸酶 ,肠道活性最高 ,自幽门盲囊起依次递降。食道和胃酸性磷酸酶活性明显低于肠 ,胃和肠酸性磷酸酶的最适 pH均为 5 .3。 (3)肠道中羧酸酯酶活性明显高于胃 ,且 2者羧酸酯酶最适 pH差别较大 ,分别为 8.4和 6 .8。(4)胃蛋白酶活性明显高于肠道 ,胃蛋白酶最适pH为 2 .6 ,肠蛋白酶最适 pH为 9.4。 (5 )胃淀粉酶活性明显低于肠道 ,胃淀粉酶最适 pH为 4 .6 ,肠道淀粉酶最适pH为 7.0。这表明许氏平对蛋白质的初步消化在胃中进行 ,在肠中进一步消化和吸收 。

The observation was conducted after the Sebastes schlegeli were starved for 72 h. Five enzymes were tested along the digestive tract. The alkaline phosphatase activity is high in the intestine with the optimum pH 9.7 and the acid phosphatase activity in the intestine is significantly higher than that in the stomach and the optimum pH of the enzyme in both stomach and intestine are 5.3. The carboxylic esterase activity in the intestine is obviously higher than that in the stomach and the optimum pHs in stomach and intestine are very different, which are 6.8 and 8.4, respectively. The proteinase activity in the stomach is much higher than that in the intestine and the optimum pHs are 2.6 and 9.4, respectively. The amylase activity in the stomach is much lower than that in the intestine and the optimum pHs are 4.6 and 7.0, respectively. It comes to the conclusion that the digestion of protein is mainly conducted in the stomach and the digestion of carbohydrates and lipid is mainly conducted in the intestine.