硫化物对凡纳滨对虾（Litopenaeus vannamei）的毒性效应研究

发布时间：2018-07-29 08:39

【摘要】：本文报道了水体硫化物对凡纳滨对虾的毒性效应,从生理生化、代谢组学、肠道健康等方面,探讨了硫化物对凡纳滨对虾的影响,研究结果为完善水生动物毒理学提供了基础资料,同时也将有助于缓解硫化物对凡纳滨对虾负面影响方法的研究。主要结果和结论如下:在盐度25psu和pH7.96±0.19条件下24h、48h、72h和96h时硫物化对凡纳滨对虾的半致死浓度分别为8301.9、6986、5643.2和4254.8μg/L,安全浓度为425.5μg/L。将凡纳滨对虾暴露在 0、425.5μg/L(1/10LC50-96h)和 851μg/L(1/5LC50-96h)的硫化物浓度下,进行了为期21天的慢性暴露,研究了硫化物对该对虾生长、能量代谢、血清代谢组学、及其肠道健康和菌群的影响。结果发现,随着硫化物浓度的升高,凡纳滨对虾的成活率显著降低,增重率和肝体比各组间并没有显著差异,肝胰腺和肌肉中的糖原含量降低,且肝胰腺中细胞色素C氧化酶的活性显著降低,但血清中的血糖、乳酸含量及乳酸脱氢酶的活性显著上升。代谢组学分析显示,在425.5μg/L浓度的硫化物暴露条件下,血清中的丙酮酸、琥珀酸、甘氨酸、丙氨酸和脯氨酸等代谢物显著下调,在851μg/L浓度的硫化物暴露下,血清中的磷酸盐、琥珀酸、丙氨酸、丝氨酸和组氨酸等代谢物也显著下调。下降可能因凡纳滨对虾在硫化物慢性暴露下,干扰了虾体内的蛋白质合成,增强了糖异生的作用,并加速了 ATP在生物合成及三羧酸循环中作为底物的消耗,促使虾体提供额外的能量来缓解硫化物的暴露。此外,凡纳滨对虾在不同浓度硫化物暴露下的血清中天冬氨酸、苯丙氨酸、马来酸及焦谷氨酸等代谢物均显著上调,说明在慢性硫化物暴露下,不仅对凡纳滨对虾体内的能量代谢造成干扰,并且对虾体的健康状况也造成了一定的影响。随着硫化物浓度的增加,对虾肠道损伤加重,炎症和免疫相关细胞因子产生一系列应激反应以及会对肠道微生物菌群结构造成影响。暴露在硫化物条件下,对虾肌肉生长抑制素(MSTN)的表达显著下调,热休克蛋白因子(HSF1)的表达在硫化物浓度为851μg/L时显著上升,但在对照组和425μg/L没有显著差异,肿瘤坏死因子(TNF-α)和C型凝集素3(CTL3)在425μg/L时的表达都显著上升,但在851μg/L时的表达都下降。硫化物也改变了肠道微生物的菌群结构,大量致病菌如:蓝细菌(Cyanobacteria)、弧菌(Vibrio)、发光杆菌(Photobacterium)的丰富度随着硫化物浓度增加显著增长,同时抵抗外来致病菌的益生菌梭菌(Fusobacteria)和适应硫化物暴露的绿菌(Chlorobi)的丰富度也显著增加。而硫酸盐还原细菌即硝化螺旋菌(Nitrospira)在硫化物暴露下消失。一些能适应硫化物暴露相关的微生物如:微杆菌(Microbacterium)/副衣原体(Parachlamydia)和希瓦氏菌(Shewanella)也出现显著下降现象,下降可能因其未适应高浓度硫化物暴露环境,具体原因待深入研究。其他微生物在硫化物暴露下也有显著性差异,由于目前对这些微生物在水生生物毒理方面的功能研究有限,文章中未作深入讨论,但本研究结果将为进一步的探究提供基础研究信息,并对在硫化物暴露下甲壳动物肠道健康的研究提供了新方向。
[Abstract]:The toxic effects of sulfides on Penaeus vannamei were reported in this paper. The effects of sulfides on Penaeus vannamei were discussed from physiological, biochemical, metabolic and intestinal health. The results provided a basic information for improving the toxicology of aquatic animals, and would also help to alleviate the negative effects of sulfide on Penaeus vannamei. The main results and conclusions are as follows: in the conditions of salinity 25psu and pH7.96 + 0.19, the semi lethal concentration of sulphide to Penaeus vannamei at 24h, 48h, 72h and 96h respectively is 8301.969865643.2 and 4254.8 mu g/L, and the safe concentration is 425.5 u g/L. to expose Penaeus vannamei to 425.5 mu g/L (1/10LC50-96h) and 851 micron g/L. The effects of sulfide on the growth, energy metabolism, serum metabolism, and intestinal health and bacteria groups were studied for 21 days of chronic exposure. The results showed that the survival rate of Penaeus vannamei decreased significantly with the increase of sulfide concentration, and there was no significant difference between the weight gain rate and the liver body ratio in the hepatopancreas. The content of glycogen in the glands and muscles decreased, and the activity of cytochrome C oxidase in the hepatopancreas decreased significantly, but the blood sugar, lactic acid content and the activity of lactate dehydrogenase in the serum were significantly increased. The metabolomics analysis showed that pyruvic acid, succinic acid, glycine, alanine and proline in the blood were exposed to the concentration of 425.5 u g/L. The metabolites such as ammonia were significantly down, and the metabolites such as phosphate, succinic acid, alanine, serine and histidine in the serum were also significantly reduced under the exposure to 851 g/L concentration of sulfides. The decrease may interfere with the egg white synthesis in shrimp, enhance the effect of sugar isogenesis, and accelerate the AT The consumption of P as a substrate in biosynthesis and the three carboxylic acid cycle encourages shrimp to provide additional energy to alleviate sulphide exposure. In addition, the metabolites of aspartic acid, phenylalanine, maleic acid and pyroglutamic acid in serum of Penaeus vannamei in different concentrations of sulfide exposure are significantly up-regulated, indicating that under chronic sulfide exposure, It not only interferes with the energy metabolism in the Penaeus vannamei, but also affects the health of the shrimp body. With the increase of sulfide concentration, the damage of the intestinal tract is aggravated, the inflammatory and immune related cytokines produce a series of stress reactions, and it will affect the structure of the intestinal microflora. Exposed to vulcanization The expression of MSTN was significantly down, and the expression of heat shock protein factor (HSF1) increased significantly when the concentration of sulfide was 851 u g/L, but there was no significant difference between the control group and 425 g/L. The expression of tumor necrosis factor (TNF- a) and C type agglutinin 3 (CTL3) increased significantly at 425 u g/L, but at 851 um g/L. The sulfide also changed the structure of the intestinal microflora, and a large number of pathogenic bacteria such as Cyanobacteria, Vibrio, and Photobacterium were increased significantly with the increase of sulphide concentration, while the bacteria resistant to the bacteria of the bacteria (Fusobacteria) and the green adapted to the sulphide exposure. The richness of bacteria (Chlorobi) also increased significantly. The sulfate reducing bacteria (Nitrospira) disappeared under sulphide exposure. Some microbes that can adapt to sulfide exposure, such as microbacilli (Microbacterium) / Chlamydia (Parachlamydia) and sivysiella (Shewanella), have also decreased significantly. It does not adapt to the high concentration of sulfide exposure environment, specific reasons for in-depth study. Other microorganisms have significant differences under sulfide exposure, due to the limited research on the function of these microorganisms in aquatic biological toxicology, but the article is not discussed in depth, but the research results will provide a basic research letter for further research. It also provides a new direction for the research of intestinal health of crustacean under sulfide exposure.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S917.4

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