氨氮胁迫对方斑东风螺溶菌酶及3种常见消化酶活力的影响

Effects of ammonia-N stress on activities of lysozgme and three digestive enzymes of Babylonia areolata

为揭示方斑东风螺(Babylonia areolata)应对氨氮(NH4-N)急性胁迫时的生理变化,分别于不同NH4-N浓度和时间下测定其体内溶菌酶及3种消化酶的活力。结果表明,实验剂量和实验时间均显著影响这4种酶的活力(P<0.05)。与对照组比较,方斑东风螺经NH4-N胁迫后:1)溶菌酶活力随着胁迫时间的延长总体呈现"抑制–诱导"趋势;2)低质量浓度NH4-N (22 mg·L^–1)对胃蛋白酶活力随时间的延长表现出"诱导–抑制"趋势,而其他质量浓度总体表现为"抑制–诱导"趋势;3)脂肪酶活力随着NH4-N处理时间的延长,总体上呈现抑制作用或与对照组呈相似水平;4) NH4-N处理时间显著影响方斑东风螺淀粉酶的活力,但各处理组的淀粉酶活力相比对照组在处理时间较短的情况下并无太大的诱导或抑制作用。综上,水体中的NH4-N会影响方斑东风螺这4种消化酶的活力。

In this paper, the effects of ammonia-N(NH4-N) stress on the activities of lysozgme and three digestive enzymes of Babylonia areolata were studied to reveal its physiological changes. The results show that both the concentration and treatment time of NH4-N had a significant effect on the activities of digestive enzymes of B. areolata(P<0.05). Compared with the control group:1) As the treatment time of NH4-N increased, the lysozyme generally demonstrated a suppression-induction trend. 2) The lower concentration of NH4-N(22 mg·L^–1) showed an induction-suppression trend to the pepsin activity, while the other concentrations generally showed a suppression-induction trend. 3) The lipase activity of B. areolata was generally suppressed or similar with that of the control group with the prolongation of treatment time. 4) The NH4-N treatment time affected the amylase activity significantly, but in the case of short treatment time, the lysozgme activities of treatment groups did not have much induction or suppression. In conclusion, the stress of ammonia-N can influence the activities of these four digestive enzymes of B. areolata.