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Biomarker assays are widely used as proxies for contaminant-induced effects in aquatic organisms. However, in many cases, their intrinsic natural variability due to exogenous and endogenous factors makes the interpretation of biomarker data difficult. In the present study, we investigated the natural fluctuations of six hepatic biomarkers, namely ethoxyresorufin-O-deethylase (EROD) in fish and pentoxyresorufin-O-deethylase (PROD) in crustacea, catalase (CAT), carboxylesterase (CbE), glutathione-S-transferase (GST), total glutathione peroxidase (GPX) and glutathione reductase (GR) in two deep-sea fish species, namely Alepocephalus rostratus and Lepidion lepidion and the decapod crustacean Aristeus antennatus. The NW Mediterranean deep-sea environment is characterized by very stable temperature and salinity conditions, allowing the exclusion of these two factors as potential sources of interference with biomarker activities. Biomarker results exhibited a clear influence of reproductive processes on enzyme activities, in particular in A. rostratus, which presented a pronounced seasonal pattern linked to variations in the gonadosomatic index (GSI). In addition, other factors such as food availability may also have influenced the observed variability, in particular in specimens of L. lepidion, which did not exhibit variations in reproductive activity throughout the sampling period. Depth-related variability did not exhibit a clear trend and fluctuations across sampling depths were not attributable to any specific factor. Body size had also a significant influence on some biomarkers, although allometric scaling of certain enzyme activities appears to be species-specific. The present work has thus shown that despite the lack of fluctuations of abiotic parameters such as temperature and salinity, biomarker activities in deep-sea organisms still exhibit significant variability, mainly as a result of reproductive processes and food availability.  相似文献   

3.
以草鱼为实验对象,采用不同浓度的十二烷基硫酸钠(SDS)进行10天暴露实验,研究阴离子表面活性剂对鱼类抗氧化酶的影响。急性毒性实验表明,SDS对草鱼的96hLC50为5·2mg/L。亚致死浓度SDS暴露可导致草鱼超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性发生变化。在所有受检组织中,SOD和GSH-Px活性在暴露初期均受到不同程度的诱导,但随着SDS浓度升高和暴露时间延长,酶活性均呈明显的下降趋势,提示SDS暴露所引起的酶活性变化与暴露浓度和暴露时间有一定的相关性。此外,实验还显示两种抗氧化酶在草鱼各组织中的分布均存在明显差异。其中,肝脏SOD和红细胞GSH-Px活性较高,易于检测,且对SDS胁迫敏感。这些结果表明,SDS暴露对草鱼具有一定毒性,对抗氧化酶活性亦有明显的负面影响。  相似文献   

4.
In recent years several studies reported the regulation by growth hormone (GH) of the expression of a variety of P450 forms in mammals. However the effect of GH on the xenobiotic-metabolizing enzymes of fish are still unknown. The aim of this work was to investigate the effects of ovine GH—a growth hormone known to be efficient in trout—on the cytochrome P450 level and on aryl hydrocarbon hydroxylase, aminopyrine-N-demethylase, glucuronyl transferase and glutathione transferase activities in trout. The GH-implanted trout (n = 50) each received a single cholesterol pellet containing ovine GH and were compared to control animals (n = 50) receiving a single cholesterol pellet without GH. After 15 days fish were killed and the liver and gills were excised for the measurement of xenobiotic-metabolizing enzyme activities. GH treatment significantly decreased the level of hepatic cytochrome P450 and the activities of cytochrome P450 dependent monooxygenases. In contrast, no significant effect of the treatment was observed on the glutathione transferase and UDP-glucuronyl transferase activities. Moreover, GH treatment had no effect on branchial phase I and phase II enzyme activities. This study provides evidence that GH level significantly affects the expression of several members of the hepatic cytochrome P450 family in trout.  相似文献   

5.
Aim of this study was to determine the extent of pollution in the West Black Sea Coast of Turkey by measuring CYP1A associated EROD activity, phase II enzyme, glutathione S-transferase and antioxidant enzymes, catalase and glutathione reductase activities and immunochemical detection of CYP1A protein level in the liver of mullet. The fish samples were caught from six locations having a varying degree of pollution in the West Black Sea Region of Turkey in August 2005, 2006 and 2007. Mullets caught from Zonguldak Harbour, Ere?li Harbour and Gülüç Stream’s Mouth displayed 6–9-fold higher EROD, 2–4-fold higher glutathione S-transferase and 2–3-fold higher catalase activities than the reference site, Amasra. Total polyaromatic hydrocarbon levels in mullets caught from these locations were also significantly higher (2–4-fold) than Amasra. The results of this study indicate that Zonguldak Harbour, Ere?li Harbour and Gülüç Stream are highly polluted by polycyclic aromatic hydrocarbons and related contaminants.  相似文献   

6.
The polysubstrate monooxygenase system has been shown to be highly responsive to chemical pollution. The present study summarizes the enzyme based biomonitoring of the waste waters released by a pulp mill producing unbleached pulp and paperboard. Cytochrome P4501A enzyme activities of feral and caged fish, as well as cultures of fish hepatocytes, were tested. The 7-ethoxyresorufin-O-deethylase (EROD) activity was clearly induced in fish hepatocytes exposed to biotreated unbleached pulp mill effluent fractions in vitro. The effluent increased EROD activities also in feral perch, compared with controls. Caging experiments showed similar effects to those seen in feral fish: however, the maximal induction coefficients observed were higher. Unbleached effluents contain compounds that are able to affect the P4501A activities in fish.  相似文献   

7.
Alterations to hepatic xenobiotic metabolizing enzymes (XMEs) is an important biomarker of contaminant exposure in aquatic toxicology. Measurement of XMEs in fish liver slices in vitro is an emerging tool for examining enzyme activity and response within the intact 3-D architecture of the liver tissue. We examined integrated phase I/phase II, and phase II metabolism of XMEs from liver slices in control and B[a]P-treated rainbow trout and channel catfish. Fluorescent assay substrates to measure rates of metabolism included 7-methoxycoumarin (7-MC), 7-ethoxycoumarin (7-EC) and 7-hydroxycoumarin (7-HC). Time-dependent increases in metabolism, and a lower rate of 7-MC metabolism compared with 7-EC metabolism, were observed at all time points for both fish species. In rainbow trout, B[a]P pretreatment caused a 10-fold increase in phase I metabolism of both 7-MC and 7-EC, and a 1.6-fold increase in phase II metabolism of 7-HC. Phase I activity in channel catfish was not notably altered by B[a]P pretreatment. However, B[a]P pretreatment in channel catfish caused a 48% decrease in phase II metabolism of 7-HC. These results indicate differences in baseline and B[a]P-altered XME profiles between rainbow trout and channel catfish.  相似文献   

8.
本文在太平洋深海沉积物中分离得到一株孔雀石绿降解菌株,鉴定命名为Tenacibaculum sp.HMG1。通过菌株生长实验和高效液相色谱的研究表明, HMG1菌株可以在20 mg/L的孔雀石绿中维持较快的生长速率,并且在12 h内可降解98.8%的孔雀石绿,这证明该菌株具有很高的孔雀石绿耐受能力和降解活性。通过基因组测序在HMG1菌株发现一条过氧化物酶基因可能参与了孔雀石绿的降解,随后利用原核表达获得了相应的重组蛋白。实验表明,该重组过氧化物酶具有极强的活性,可在1000 mg/L的孔雀石绿中发挥降解功能。本文利用液相色谱-质谱联用(LC-MS)技术对孔雀石绿的菌株降解产物和重组酶降解产物进行鉴定,并基于鉴定结果推测了两种降解途径。结果发现两种降解方式存在共同的降解途径。此外,孔雀石绿降解条件的实验结果证明重组过氧化物酶可以在低温(20℃)、复杂的pH值(6.0–9.0)、高盐度(100 mmol/L)、金属离子和EDTA等反应条件下依旧维持很高的孔雀石绿降解活性。以上实验结果表明,HMG1菌株和重组过氧化物酶均在孔雀石绿污染生物修复方面具有很大潜力。  相似文献   

9.
In Toulon Bay (France), very high phosphatase activities have been found in the zooplankton fraction>90 microm. This work was intended to specify their origin. For that purpose, larvae, juvenile and adult Crustacea (Copepods: Calanoids, Cyclopoids, Branchiopods: Cladocera, and Cirripeds) were isolated. Their activities were measured using paranitrophenyl phosphate dissolved in sea water in order to calculate Km (the enzyme half saturation concentration) and Vmax (the reaction rate when the enzyme is saturated with substrate). Vmax were referred to protein contents of the isolated organisms to calculate specific activities. For all zooplankton groups high and low affinity phosphatase activities were found. The low affinity enzyme was responsible for at least 70% of the total phosphatase activity. Its specific activity was higher for larvae than for copepodites and adults. In Cirriped nauplii this activity was particularly high with values which were several hundred times higher than that in other Crustacea. These enzymes had optimum pH close to 8.4, magnesium requirement and were competitively inhibited by orthophosphate. Experiments with intact and lysed Cirriped nauplii confirmed that living organisms had only a weak external activity and showed that most of the activity of these larvae was primarily intracellular.  相似文献   

10.
The aim of the present study was to investigate the responses of phase I and II biotransformation enzymes and levels of PAHs in the Mediterranean mussel (Mytilus galloprovincialis, Lamarck, 1819) collected from three sites at different distance from an oil refinery. Phase I enzyme activities as NAD(P)H-cyt c red, NADH ferry red, B(a)PMO and phase II as UDPGT, GST were measured in digestive gland while 16 PAHs (US-EPA) in whole soft tissue. An added value to the data obtained in the present study rely on the RDA analysis which showed close correlations between PAHs levels and phase I enzyme activities in mussels collected in front of the refinery. And again a significant spatial correlation between B(a)P levels and NADPH-cyt c red activities was observed using linear models. No differences among sites for B(a)PMO and phase II GST activities were observed, while the application of UDPGT as biomarkers requires further investigation.  相似文献   

11.
利用生物化学的方法,研究了赤潮异弯藻、亚历山大藻和中肋骨条藻抗氧化酶活性对UV-B辐射增强的响应变化。结果表明:(1)不同赤潮微藻的抗氧化酶活性对UV-B辐射增强的响应变化是不同的。(2)不同的抗氧化酶活性对UV-B辐射增强的响应变化同样存在明显的差异。(3)与过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)相比,超氧化物歧化酶(SOD)活性对UV-B辐射增强的响应最敏感,谷胱甘肽过氧化物酶(GPX)活性的响应变化最不明显。3种赤潮微藻SOD活性的变化是指示UV-B辐射增强的优选生物学指标。  相似文献   

12.
In the present study the bioaccumulation of poly chlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) as well as the responses of a suite of biochemical parameters were investigated in a standardized carp (Cyprinus carpio) fish line. Carps were caged for 2 to 8 weeks at two Amsterdam freshwater sites: the relatively unpolluted Outer IJ and the heavily polluted Volgermeerpolder. The primary objective of the experiments was to develop a reliable and reproducible method to monitor the inland water pollution and to classify the environmental quality of freshwater sites. The highest tissue levels of organic trace pollutants were generally found in carp that was caged for at least four weeks at the polluted site. Hepatic phase I enzymes showed the highest pollution-induced responses, while phase II enzymes and serum transaminases were less sensitive. The antioxidant enzymes showed virtually no response to pollutants. In order to assess effects on the balance between bioactivation and detoxication the ratio between phase I (EROD) and phase II (GST or UDPGT) activities was introduced as a biotransformation index (BTI). Highest BTI values were observed in carp that was caged for 4 to 6 weeks at the polluted site. The BTI values decreased after eight weeks of exposure due to elevated phase II activities.  相似文献   

13.
为了评估缺氧对大弹涂鱼的影响,本研究通过模拟缺氧环境(溶解氧1.5±0.11mg/L),探究急性缺氧(1h,3h和6h)对大弹涂鱼缺氧相关基因表达、蛋白含量及酶活性的影响。结果显示,6h缺氧过程中,对照组实验鱼肝脏中缺氧相关基因表达、蛋白含量和酶活性无显著性差异;缺氧处理组实验鱼肝脏中缺氧诱导因子(HIF)、葡萄糖转运体、脯氨酰羟化酶和Bcl2/腺癌E1B19KD交互蛋白3基因的表达量和蛋白含量在6h处理时间内逐渐上调,但肿瘤抑制蛋白p53基因的表达量和蛋白含量在1h时显著最高;缺氧处理组实验鱼肝脏中乳酸脱氢酶、柠檬酸合酶和丙酮酸激酶活性逐渐下调,在6h时达到最低;但肝脏中葡萄糖激酶和磷酸果糖激酶活性在3h时显著增加,随后逐渐降低,在6h时达到最低;在整个缺氧过程中,缺氧处理组实验鱼肝脏中缺氧相关基因表达、蛋白含量和酶活性显著高于对照组。本研究结果表明,HIF信号通路在缺氧应答中被激活;缺氧胁迫会抑制鱼类需氧代谢的生理过程。  相似文献   

14.
The effects of waterborne nitrite (3 mg/l NO2) on channel catfish were studied to evaluate changes in hematological parameters and phase I-II biotransformation in liver slices. Nitrite-exposed fish had significantly higher methemoglobin, blood and liver nitrite, and significantly lower pO2 than control fish. Total phase I-mediated metabolism of 7-ethoxycoumarin (EC) was not altered in nitrite-exposed fish compared with control fish (291 +/- 43 and 312 +/- 20 pmol/mg/h, respectively). However, phase II glucuronosyltransferase-mediated metabolism of 7-hydroxycoumarin (HC), both as a phase I metabolite of EC and as a parent substrate, was elevated in nitrite-exposed fish (204 +/- 17 and 1007 +/- 103 pmol/mg/h, respectively) as compared to control fish (149 +/- 14 and 735 +/- 87 pmol/mg/h) (P < 0.05). Sulfotransferase-mediated metabolism of HC (as a metabolite of EC and as a parent substrate) was not notably altered in nitrite-exposed fish (95 +/- 16 and 617 +/- 33 pmol/mg protein/h, respectively) as compared with control fish (118 +/- 24 and 575 +/- 55 pmol/mg/h, respectively). These studies indicate that in vivo nitrite exposure and associated changes in hematological parameters do not appear to affect hepatic phase I EC biotransformation in channel catfish. However, subtle but significant changes in phase II glucuronidation, but not sulfation activity, were observed. The mechanism of these alterations is unclear. However, the data suggest that environmentally realistic concentrations of nitrite may affect the dynamics of conjugative metabolism in exposed fish.  相似文献   

15.
南美白对虾早期幼体消化酶活力的研究   总被引:8,自引:1,他引:8       下载免费PDF全文
以酶学分析方法对南美白对虾(Penaeus vannamei Boone)幼体及仔虾 4种消化酶的活力进行了分析测定,结果表明:南美白对虾早期幼体消化酶活力表现差异,类胰蛋白酶、胃蛋白酶的活力为无节幼体(N)<溞状幼体(Z)<糠虾幼体(M)<仔虾(P),类胰蛋白酶的活力比胃蛋白酶高2倍左右;淀粉酶的活力Z-M期表现较高,以后随幼体发育淀粉酶活力明显降低;脂肪酶活力在早期幼体发育阶段变化不大,且活力较低。  相似文献   

16.
植酸对牙鲆生长和消化酶活性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
以鱼粉为主要蛋白源,在基础饲料中分别添加不同含量的植酸纳使植酸水平分别达到0.04%(对照组)、0.21%、0.44%和0.81%,研究不同含量植酸对牙鲆(Paralichthys olivaceus)(2.58 g±0.01 g)摄食、生长和消化酶活性的影响.实验在室内循环水养殖系统中进行,为期10周.结果表明,植酸处理组牙鲆摄食率(2.4%、2.5%和2.4%)显著高于对照组(2.1%)(P<0.05),但植酸处理组之间差异不显著(P>0.05).植酸处理组(59.47、61.27和64.82 U/mg蛋白)胃蛋白酶比活力显著低于对照组(79.34 U/mg蛋白),但植酸处理组之间差异不显著.各处理组之间牙鲆肝脏、肠和胃中淀粉酶比活力及肝脏和肠中蛋白酶比活力均无显著差异.随着饲料中植酸含量的增加,干物质和蛋白质表观消化率显著下降.同时,牙鲆特定生长率、饲料转化率、蛋白质效率和净蛋白质利用率随着饲料中植酸含量的升高均呈下降趋势,其中各处理组之间牙鲆特定生长率无显著差异,而植酸处理组饲料转化率(74.0%、73.7%和69.2%)则显著低于对照组(84.0%),0.81%植酸处理组蛋白质效率(1.37)和净蛋白质利用率(25.0%)显著低于对照组(1.64和30.6%).本实验结果表明,随着饲料中植酸含量的增加,牙鲆生长性能和胃蛋白酶比活力呈下降趋势.植酸对牙鲆生长的抑制作用将随着其含量的升高或实验周期的延长突现出来.  相似文献   

17.
半滑舌鳎仔稚鱼消化酶活性的变化   总被引:9,自引:0,他引:9  
对半滑舌鳎不同发育阶段主要消化酶(酸性蛋白酶、碱性蛋白酶、淀粉酶、脂肪酶)以及与消化吸收相关的碱性磷酸酶的活性变化进行了测定。结果表明,半滑舌鳎在仔鱼发育早期即可检出酸性蛋白酶和碱性蛋白酶的活力,碱性蛋白酶的2个极低值分别出现在仔鱼开口期和仔稚鱼的转交期,从孵化后23d左右胃腺出现时,酸性蛋白酶的活性开始明显升高。早期仔鱼体内表现出较强的淀粉酶活性,孵化后12d其活性急剧下降,并一直保持较低的比活力状态。脂肪酶的活性在半滑舌鳎早期仔鱼体内一直较低,进入稚鱼期后开始缓慢上升。碱性磷酸酶活性在变态结束后出现大幅度的升高,这标志着肠组织结构和肠道消化功能的完善。  相似文献   

18.
黄斑蓝子鱼(Siganus canaliculatus)是可养殖的少数植食性海水鱼之一。为进一步了解黄斑蓝子鱼的消化生理特征,以及将海藻更科学地应用于配合饲料中,本研究采用不同类型饵料:冰鲜杂鱼(Raw fish,RF)、配方饲料(Formulated diet,FD)、浒苔(Enteromorpha prolifra,EP)和龙须菜(Gracilaria lemaneiformis,GL)饲喂黄斑篮子鱼8周,分析鱼内脏特征及其消化酶活性的变化情况。研究结果显示:RF组和FD组鱼的肝体比和脏体比,以及EP组和GL组鱼的肠长比(Relative intestine length,RIL),都显著高于其他组。此外,分析不同处理组鱼的肝和前肠组织形态结构,发现RF组肝细胞核被脂滴挤到细胞边缘,两海藻组前肠黏膜的皱褶程度最高。养殖前三周,鱼的消化酶活性变化波动明显,而之后消化酶活性趋于平稳。消化道的蛋白酶,脂肪酶和α-淀粉酶的水平分别随着日粮中蛋白质,脂肪和碳水化合物水平的变化而变化。虽然,海藻饵料显著降低了黄斑篮子鱼的胃蛋白酶活性,但是提高了机体RIL和前肠黏膜的皱褶程度以弥补其对胃蛋白酶的负面影响。以上结果表明黄斑蓝子鱼的消化系统可较好地适应不同类型的饵料,其适应时间大约为三周。因此,本研究结果也暗示黄斑蓝子鱼也具有一些杂食性鱼类的属性。  相似文献   

19.
cDNA clones for glutathione S-transferases A (GST-A) and A1 (GST-A1) from plaice (Pleuronectes platessa) were expressed as N-terminally 6XHis tagged proteins in Escherichia coli and purified to homogeneity from Ni-NTA silica. GST-A was an efficient catalyst for conjugation of unsaturated alkenals derived from peroxidation of polyunsaturated fatty acids with the highest activity observed with trans-non-2-enal (8 micromol min(-1) mg(-1)). GST-A1 was a very efficient Se-independent glutathione peroxidase with an activity towards cumene hydroperoxide of 25 micromol min(-1) mg(-1). Although the enzymes exhibited moderately high activities towards the model substrate 1-chloro-2,4-dinitrobenzene (CDNB) they exhibited little or no activity towards other common prototypical xenobiotic substrates. Together with data for ontogeny, tissue distribution and inducibility of these enzymes, we contend that a primary function of these enzymes is protection from the harmful effects of lipid peroxidation products generated naturally or exacerbated by xenobiotic exposure.  相似文献   

20.
The aim of this study was to determine the detoxication capacity and the sensitivity to pollutants of fish living in a pristine environment such as the Antarctic Ocean. Forty specimens of Pagothenia bernacchii collected during the Antarctic summer of 1991–1992 were divided into three groups, and were treated with 10 mg/kg of B(α)P, 50 mg/kg of PCBs and corn oil and sacrificed after 2, 4 and 10 days. The mixed function oxidase activity measured in these fish through the test of BPMO, EROD and BROD activities revealed that both B(α)P and PCBs are effective in inducing this enzyme system. Owing to the slow metabolic rate of this species, related to the low ambient temperature of its natural habitat, the highest level of induction was monitored after 10 days i.e. much later than in fish of temperate seas.  相似文献   

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