温度对岩扇贝无水保活及抗氧化酶活力的影响

摘要

Temperature was one of the key factors for the living environment of aquatic organisms,especially for shellfish.The effects of temperature was studied on the survival rate and the median lethal time (LT50) of the rock scallop Crassadoma gigantea,and the effects of temperature stress on the antioxidant enzymes of rock scallop Crassadoma gigantea were studied in order to explore the effects of temperature on keeping-alive without water and antioxidant system of the rock scallop Crassadoma gigantea.The rock scallop Crassadoma gigantea (shell length (39.7± 5) mm) at different temperatures (5℃ and 15℃),humidity (moisture treatment,not moisturizing treatment) and oxygen (aerobic treatment,not aerobic treatment) in laboratory was studied by the survival analysis and the analysis of factors affecting the effects of the median lethal time (LT50) in order to investigate the effects of temperature on the survival rate and the median lethal time of the rock scallop Crassadoma gigantea.Results showed that low temperature,moisture and aerobic treatment can significantly improve the survival rate and the median lethal time of the rock scallop Crassadoma gigantea (P＜0.05).The effect of temperature on the survival rate and the median lethal time of the rock scallop Crassadoma gigantea was most significant,followed by the effect of oxygen,and that of humidity was the most weakest.Interaction between temperature and humidity,temperature and oxygen significant interaction(P＞0.05),and interaction between humidity and oxygen interaction was not significant (P＜0.05) in the interaction of three factors.It provided an important basis for the determination of the rock scallop Crassadoma gigantea in the seedling transportation time.In the article,the rock scallop Crassadoma gigantea larvae antioxidant enzymes activity was detected,including SOD activity,CAT activity,T-AOC activity (superoxide dismutase activity,catalase activity,total antioxidant capacity) changes through raising the temperature from the low temperature (5℃,10℃,15℃,20℃,25℃),to explore the change of the antioxidant enzymes activity under the influence of temperature on the rock scallop Crassadoma gigantea larvae.The SOD activity was significantly lower than that of the other groups (P＜0.05) at 5℃,and the CAT activity had no significant difference between groups (P＞0.05),and the T-AOC level was the lowest significantly below 15℃,25℃ (P＜0.05).The SOD and CAT activity had no significant difference in the same experimental time (P＞0.05),and the T-AOC activity temperature was significantly higher than the rest of the group (P＜0.05) when temperature at 10℃ and 20℃.The SOD activity had no significant difference (P＞0.05) between groups at 25℃,and the CAT activity was significantly higher than 5℃ 10℃,15℃ group (P＜0.05).The T-AOC activity was only lower than 15℃ group (P＞0.05).It indicated that the high temperature had a clear inducing effect on the CAT activity in the rock scallop Crassadoma gigantea larvae,and had a significant inhibitory effect on the T-AOC activity.The low temperature had a significant inhibitory effect on the activity of T-AOC in the tissue fluid of the scallop.The above results showed that the high and low temperature had a significant effect on the antioxidant enzymes activity of the rock scallop Crassadoma gigantea larvae.%温度是水生生物尤其是贝类生存环境的关键因素之一.为了探究温度对岩扇贝无水保活和抗氧化系统的影响,本试验进行了温度对不同干露条件下岩扇贝存活率、半致死时间(LT50)的影响以及温度胁迫对岩扇贝幼贝抗氧化酶活力的影响两项不同的试验.为了探明温度对岩扇贝存活率和半致死时间的影响,在实验室条件下,进行了的岩扇贝(壳长为(39.7±5.0) mm)在不同温度(5℃、15℃)、湿度(保湿组、不保湿组)和氧气(充氧组、不充氧组)环境下的生存分析、影响半致死时间的因素效应分析.结果发现低温、保湿、充氧均可以显著提高岩扇贝存活率、半致死时间(P＜0.05),其中温度变化对岩扇贝的半致死时间影响最显著,其次时氧气,最后是湿度.在三个因素的交互作用中,温度和湿度、温度和氧气交互作用显著(P＞0.05),湿度和氧气交互作用不显著(P＜0.05).这为确定岩扇贝苗种运输时间提供了重要依据.为探究温度变化对岩扇贝幼贝抗氧化系统的响应,试验从低温开始逐渐升温(5℃、10℃、15℃、20℃、25℃),检测岩扇贝幼贝抗氧化酶活力(超氧化物歧化酶活力SOD、过氧化氢酶活力CAT、总抗氧化能力T-AOC)的变化.结果显示,岩扇贝幼贝SOD活力在5℃时显著低于其余组SOD活力(P＜0.05),在10℃至25℃间,SOD活力不存在显著性差异(P＞0.05);CAT活力在5℃至20℃间变化不显著(P＞0.05),在25℃时显著高于其余组CAT活力(P＜0.05);T-AOC水平在15℃时显著高于其余组(P＜0.05),温度从15℃升高或降低T-AOC活力都会显著下降(P＜0.05),降温下降幅度显著高于升温(P＜0.05).这表明高温对岩扇贝幼贝组织液中CAT活力有着明显的诱导作用、对T-AOC活力有着明显的抑制作用;低温对岩扇贝幼贝组织液中SOD、T-AOC活力有着明显的抑制作用.上述结果表明:温度过低或过高对岩扇贝幼贝的抗氧化酶活力均产生显著的影响.