Effects of a municipal effluent on the freshwater mussel Elliptio complanata following challenge with Vibrio anguillarum

The purpose of this study was to examine the cumulative effects of exposure to a pathogenic bacteria and municipal effluent in the freshwater mussel Elliptio complanata. Mussels were exposed to increasing concentrations of an ozone-treated effluent at 15°C for 7 days. A sub-group of mussels was inoculated with Vibrio anguillarum and exposed to the same conditions as above.After the exposure period, mussels were collected to assess hemocyte count and viability,immunocompetence(phagocytosis and nitrite production), oxidative stress/inflammation(cyclooxygenase and lipid peroxidation) and oxygen radical/xenobiotic scavenging activity(metallothioniens, glutathione S-transferase). The results showed that mussels exposed to municipal effluent had increased hemocyte counts, phagocytosis, nitrites, lipid peroxidation and metallothioneins. In the inoculated mussels, the same responses were observed, in addition to cyclooxygenase and glutathione S-transferase activities. Multivariate analyses revealed that(1)the response pattern changed with effluent concentration, where increased responses observed at low effluent concentrations(10%, V/V) were attenuated at higher effluent concentrations,(2)the effluent produced more pronounced changes in lipid peroxidation, metallothionein and hemocyte viability, and(3) the simultaneous presence of V. anguillarum led to more important changes in hemocyte count and viability and nitrite levels. In conclusion, the presence of V.anguillarum could alter the response of mussels to municipal effluent, which could lead to increased inflammation in mussels.     

Effect of chromium on accumulation and antioxidants in Cucumis utillissimus L.: Response under enhanced bioavailability condition

This study compares the accumulation of Cr(VI) and biochemical changes (total chlorophyll, carotenoid, protein, malondialdehyde (MDA) and cysteine contents) and roles of antioxidant enzymes (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX)) in tolerance to metal induced stress in Cucumis utillissimus L. grown in Cr contaminated soil (CS) with garden soil (GS). Furthermore, Cr bioavailability was enhanced by ethylene diamine tetra-acetic acid (EDTA) addition to the soil to forecast the plant’s accumulation pattern at elevated Cr environment. Accumulation of Cr in the leaves of the plant increased with increase in substrate metals concentration. It further increased with the addition of EDTA by 1437% and 487% in GS and CS, respectively at the highest treatment level. The lipid peroxidation increased proportionately with increase in Cr accumulation in the leaves. All the activity of antioxidant enzymes (SOD, GPX and APX) and the level of cysteine increased with dose dependant manner. SOD and cysteine were observed to be higher in the GS than in CS, but APX and GPX were found to be higher in CS than in GS. The increase in GPX and APX activities with the increase in Cr concentration could be assumed that these two enzymes have a major role in the defense mechanism towards stress induced by Cr in C. utillissimus.     

Effect of combined pollution by heavy metals on soil enzymatic activities in areas polluted by tailings from Pb-Zn-Ag mine

Some enzymatic activities were determined in the areas polluted by tailings from Tiantai Pb-Zn-Ag Mine in Zhejiang Province of China. The results indicated the soil enzymatic activities decreased significantly with increase of concentrations of heavy metals or the distance away from mining tailing center, especially dehydrogenase and urease activities. Multivariate regression analysis between heavy metal contents and soil enzymatic activities indicated that single dehydrogenase activity was very significantly correlated to combined effect of soil heavy metals in mine area. Moreover, single urease, protease and acid phosphatase activities were significantly related to the combined effect of heavy metals. The results suggest it is feasible to use soil enzymatic activities to indicate the pollution situation by combined heavy metals in the soil of mine area.     

Growth inhibition and oxidative damage of Microcystis aeruginosa induced by crude extract of Sagittaria trifolia tubers

Aquatic macrophytes are considered to be promising in controlling harmful cyanobacterial blooms. In this research, an aqueous extract of Sagittaria trifolia tubers was prepared to study its inhibitory effect on Microcystis aeruginosa in the laboratory. Several physiological indices of M. aeruginosa, in response to the environmental stress, were analyzed. Results showed that S. trifolia tuber aqueous extract significantly inhibited the growth of M. aeruginosa in a concentration-dependent way. The highest inhibition rate reached 90% after 6 day treatment. The Chlorophyll-a concentration of M. aeruginosa cells decreased from 343.1 to314.2 μg/L in the treatment group. The activities of superoxide dismutase and peroxidase and the content of reduced glutathione in M. aeruginosa cells initially increased as a response to the oxidative stress posed by S. trifolia tuber aqueous extract, but then decreased as time prolonged. The lipid peroxidation damage of the cyanobacterial cell membranes was reflected by the malondialdehyde level, which was notably higher in the treatment group compared with the controls. It was concluded that the oxidative damage of M. aeruginosa induced by S.trifolia tuber aqueous extract might be one of the mechanisms for the inhibitory effects.     

Photosynthesis and biochemical responses to elevated O3 in Plantago major and Sonchus oleraceus growing in a lowland habitat of northern China

A field experiment was carried out to compare the responses to ozone(O_3) in two common herbaceous plant species, Plantago major L. and Sonchus oleraceus L., by building open-top growth chambers in situ to simulate O_3stress(+ O_3, 85 ± 5 ppb, 9 hr/day for 30 days) in a lowland habitat in Inner Mongolia, Northern China. Responses to O_3 of gas exchange,chlorophyll a fluorescence, leaf pigment content, antioxidant capability, soluble protein content, membrane lipid peroxidation and dark respiration(R_d) were analyzed. Results showed that elevated O_3 exposure significantly reduced the light-saturated net photosynthesis(P_(Nsat)), stomatal conductance(g_s) and transpiration rate(E) in both species. Although non-significant interactive effect between species and O_3 on P_(Nsat) was analyzed, the reduction in P_(Nsat) in S. oleraceus might be due primarily to the higher fraction of close PSII reaction centers and impaired activities of plant mesophyll cells as evidences by decreased maximum efficiency of PSII photochemistry after dark adapted state(F_v/F_m) and unchanged intercellular CO_2concentration(C_i). Besides, biochemical analysis showed that S. oleraceus had lower antioxidant ability compared to P. major. As a result, S. oleraceus was damaged to the larger extent in terms of lipid peroxidation and visible O_3 injury, indicating that S. oleraceus was more sensitive to O_3 than P. major. Our results indicated that wild herbaceous plant species growing in a lowland habitat in sandy grassland were sensitive to O_3 stress and S. oleraceus can be considered as one of the bio-indicators for high O_3 concentration in semi-arid grassland of northern China.     

Cu(Ⅱ), Fe(Ⅲ) and Mn(Ⅱ) combinations as environmental stress factors have distinguishing effects on Enterococcus hirae

Pollution by various heavy metals as environmental stress factors might affect bacteria. It was established that iron(Fe(Ⅲ)), manganese(Mn(Ⅱ)) and copper(Cu(Ⅱ)) ion combinations caused effects on Enterococcus hirae that differed from the sum of the effects when the metals were added separately. It was shown that the Cu2+–Fe3+combination decreased the growth and ATPase activity of membrane vesicles of wild-type E. hirae ATCC9790 and atp D mutant(with defective FoF1-ATPase) MS116. Addition of Mn2+–Fe3+combinations within the same concentration range had no effects on growth compared to control(without heavy metals). ATPase activity was increased in the presence of Mn2+–Fe3+, while together with0.2 mmol/L N,N′-dicyclohexylcarbodiimide(DCCD), ATPase activity was decreased compared to control(when only 0.2 mmol/L DCCD was present). These results indicate that heavy metals ion combinations probably affect the FOF1-ATPase, leading to conformational changes. Moreover the action may be direct or be mediated by environment redox potential.The effects observed when Fe3+was added separately disappeared in both cases, which might be a result of competing processes between Fe3+and other heavy metals. These findings are novel and improve the understanding of heavy metals ions effects on bacteria,and could be applied for regulation of stress response patterns in the environment.     

Response of antioxidase in viscera of Pagrosuma major larvae to water soluble fraction of hydrocarbons in No.0 diesel oil

Pagrosomus major larvae were to the water-soluble fraction of hydrocarbon in No.0 diesel oil(corresponding to No.2 fuel oil) at concentration of 0,0.17,1.22 and 8.82mg/L for up to 15 days.Larvae were sampled on days 9 and 15 of the experiment.Supernatants of viscera tissue extractions were assayed for biochemical response in terms of oxidative stress-superoxide dismutase(SOD),activity of selenium-dependant glutathione peroxidase(Se-GPx) and catalase(Ca),and the concentration of reduced glutathione(CSH).On day 9 of exposure ,statistically significant dose-related increases in Se-GPx and SOD activity,and GSH concentration were observed in all cases except for Se-GPx activity under the highest dosage of hydrocarbon.However,on day 15 of exposure, a similar dose-related in all cases except for Se-GPx activity under the highest dosage of hydrocarbon.However,on day 15 of exposure, a similar dose-related response was only observed for Se-GPx activity.GSH concentration decreased and SOD activity showed no statistical difference as compared to controls.However, a significant decrease in compared to day 9 Se-GPx activity and GSH concentration, in contrast to increase SOD activity at day 15 as indicates an accelerated accumulation of H2O2 and potential oxidative damage under long term exposure of larvae to hydrocarbons.No statistical changes were observed in Ca activity throughout the experiment, possibly owing to the high efficiency of Se-GPx.A recovery experiment was performed on indicating that the response of antioxidants measured tending to returm to return to their control levels.These results prove the function of the antioxidant defense system of the larvae to the water-soluble fraction of hydrocarbons in No.0 diesel oil.     

Heavy metal availability and impact on activity of soil microorganisms along a Cu/Zn contamination gradient

All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciation and availability. We studied the effects of heavy metal speciation and availability on soil microorganism activities along a Cu/Zn contamination gradient. Microbial biomass and enzyme activity of soil contaminated with both Cu and Zn were investigated. The results showed that microbial biomass was negatively affected by the elevated metal levels. The microbial biomass-C （Cmic）/organic C （Corg） ratio was closely correlated to heavy metal stress. There were negative correlations between soil microbial biomass, phosphatase activity and NH4NO3 extractable heavy metals. The soil microorganism activity could be predicted using empirical models with the availability of Cu and Zn. We observed that 72% of the variation in phosphatase activity could be explained by the NH4NO3-extractable and total heavy metal concentration. By considering different monitoring approaches and different viewpoints, this set of methods applied in this study seemed sensitive to site differences and contributed to a better understanding of the effects of heavy metals on the size and activity of microorganisms in soils. The data presented demonstrate the relationship between heavy metals availability and heavy metal toxicity to soil microorganism along a contamination gradient.     

Potential of weed species applied to remediation of soils contaminated with heavy metals

To screen out a series of ideal plants that can effectively remedy contaminated soils by heavy metals is the main groundwork of phytoremediation engineering and the first step of its commercial application on a large scale. In this study, accumulation and endurance of 45 weed species in ]6 families from an agricultural site were in situ examined by using the pot-culture field experiment, and the remediation potential of some weed species with high accumulation of heavy metals was assayed. The results showed that Solanum nigrum and Conyza canadensis can not only accumulate high concentration of Cd, but also strongly endure to single Cd and Cd-Pb-Cu-Zn combined pollution. Thus 2 weed species can be regarded as good hyperaccumulators for the remediation of Cd-contaminated soils. Although there were high Cd-accumulation in Artemigia selengensis, Znula britannica and Cephalanoplos setosum, their biomass was adversely affected due to action of heavy metals in the soils. If the problem of low endurance to heavy metals can be solved by a reinforcer, 3 weed species can be perhaps applied commercially.     

Coking wastewater increases micronucleus frequency in mouse in vivo via oxidative stress

Coking wastewater has caused serious health risk in coal-producing areas of China, however its toxic effects have not been well understood. The genotoxicity induced by coking wastewater on mice in vivo and its possible oxidative mechanisms were investigated via observing the induction of micronuclei in polychromatic erythrocytes of mouse bone marrow, and subsequently determining the antioxidative enzyme activities （superoxide dismutase Cu, Zn-SOD, Se-dependent glutathione peroxidase, and catalase）, thiobarbituric acid reactive substance contents and protein carbonyl levels in brains and livers of mice. Results showed that the tested coking wastewater caused a significant increase of micronucleus frequencies in a concentration-dependent manner. Also, the sample increased lipid peroxidation and protein oxidation levels, which was accompanied by changes in antioxidative status. Interestingly, pre-treatment with an antioxidant （vitamin C） led to a statistical reduction in the micronucleus frequency caused by coking wastewater. This implies that coking wastewater induces evident genetic damage in mammalian cells, and exposure to polluted areas might pose a potential genotoxic risk to human beings; in the process, oxidative stress played a crucial role.     

Comparison of physiological responses to oxidative and .heavymetal stress in seedlings of rice paddy, Oryza sativa L.

ＩｎｔｒｏｄｕｃｔｉｏｎＯｒｇａｎｉｓｍｓｌｉｖｉｎｇｕｎｄｅｒｐｏｌｌｕｔｉｏｎｓｔｒｅｓｓｖａｒｉｅｄｒｅｓｐｏｎｓｅｓ,ｆｒｏｍｃｈａｎｇｅｓｉｎｇｒｏｓｓｍｏｒｐｈｏｌｏｇｙｔｏｃｈａｎｇｅｓｉｎｂｉｏｃｈｅｍｉｓｔｒｙ .Ｐｌａｎｔｓｉｎｐａｒｔｉｃｕｌａｒｈａｖｅｅｖｏｌｖｅｄｄｉｖｅｒｓｅｗａｙｓｏｆｒｅｓｐｏｎｄｉｎｇｔｏａｄｖｅｒｓｅｃｈａｎｇｅｓｉｎｔｈｅｉｒｅｎｖｉｒｏｎｍｅｎｔ.Ｐｌａｎｔｓｏｖｅｒｃｏｍｅｓｅｖｅｒｅｅｎｖｉｒｏｎｍｅｎｔａｌｓｔｒｅｓｓｂｙｄｅｖｅｌｏｐｉ…     

Assessment of oxidative stress indices in a marine macro brown alga Padina tetrastromatica (Hauck) from comparable polluted coastal regions of the Arabian Sea, west coast of India

Oxidative stress and antioxidant defence systems were assessed in a marine brown alga Padina tetrastromatica, commonly occurring from the tropics. Lipid peroxidation (LPX) and H2O2 were measured as oxidative stress markers, and antioxidant defences were measured as catalase (CAT), glutathione S-transferase (GST) and ascorbic acid (AsA), in order to understand their dissimilarity with respect to pollution levels from selective locations along the central west coast of India. A significant increased levels of LPX, H2O2, CAT and GST were observed in samples from relatively polluted localities (Colaba and Karwar) when compared to less polluted locality (Anjuna), while AsA concentration was higher in algal samples from worst polluted region of Colaba. Heavy metals such as Cd and Pb were also higher in the vicinity of polluted areas compared to reference area. Variation of oxidative stress indices in response to accumulation of heavy metals within P. tetrastromatica could be used as molecular biomarkers in assessment and monitoring environmental quality of ecologically sensitive marine habitats.     

Prolonged manganese exposure induces severe deficits in lifespan, development and reproduction possibly by altering oxidative stress response in Caenorhabditis elegans

We examined the possible multiple defects induced by acute and prolonged exposure to high levels of manganese (Mn) solution by monitoring the endpoints of lifespan,development,reproduction,and stress response.Our data suggest that acute exposure (6 h) to Mn did not cause severe defects of life span,development,and reproduction.Similarly,no significant defects could be found for the life span,development,and reproduction in animals exposed to a low concentration of Mn (2.5 μmol/L) for 48 h.In contrast,prolonged exposure (48-h) to high concentrations of Mn (75 and 200 μmol/L) resulted in significant defects of life span,development,and reproduction,as well as the increase of the percentage of population with hsp-16.2::gfp expression indicating the obvious induction of stress responses in exposed animals.Moreover,prolonged exposure (48-h) to high concentrations (75 and 200 μmol/L) of Mn decreased the expression levels of antioxidant genes of sod-1,sod-2,sod-3,and sod-4 compared to control.Therefore,prolonged exposure to high concentrations of Mn will induce the severe defects of life span,development,and reproduction in nematodes possibly by affecting the stress response and expression of antioxidant genes in Caenorhabditis elegans.     

硅对过量锰胁迫下水稻根系抗氧化系统和膜脂质过氧化作用的调控机理

揭示Mn胁迫下Si对水稻根系抗氧化系统的影响机制,可为减轻水稻Mn毒害提供重要的理论依据和技术支持.因此,本研究通过水培试验,采用两个对Mn耐性不同的水稻品种,研究Si(1.5 mmol·L-1)对Mn(2 mmol·L-1)胁迫下水稻根系抗氧化系统的影响.结果表明,在Mn胁迫下,敏感品种新香优640(XXY)根系的超...     

文蛤谷胱甘肽抗氧化系统对北部湾沉积物中可提取态重金属的响应

为识别海洋双壳类谷胱甘肽抗氧化系统对滨海沉积物重金属可提取态和总量的响应特征差异,分析了北部湾潮间带沉积物中不同形态Cu、Pb、Zn、Cd、Cr的质量分数,文蛤(Meretrix meretrix)鳃组织中w(GSH)(GSH为还原型谷胱甘肽)、w(GSSG)(GSSG为氧化型谷胱甘肽)、GPx(谷胱甘肽过氧化物酶)和GST(谷胱甘肽硫转移酶)活性,并计算w(GSH)/w(GSSG)、tGSH(总谷胱甘肽)含量和OSI(氧化逆境指数). 结果表明:w(TE-Pb)(TE-Pb为可提取态Pb,下同)、w(TE-Cr)、w(TE-Cu)、w(TE-Zn)和w(TE-Cd)平均值分别为13.40、1.93、13.19、30.09和0.10mg/kg; w(TE-Cd)占w(T-Cd)(T-Cd为总Cd,下同)的60.2%~98.1%,并且主要为弱酸溶解态和有机物及硫化物结合态;部分采样点w(TE-Pb)和w(TE-Zn)较高,二者占w(T-Pb)和w(T-Zn)的平均值分别为44.6%和56.6%;Cr、Cu分别在全部或大多数采样点以残渣态为主,可提取态含量平均仅占总量的17.9%和36.5%. 重金属的可提取态质量分数与总量的空间分布基本一致(Cr除外). 文蛤鳃中w(GSH)、w(GSSG)分别为4.07~6.06、4.01~6.59mg/g. 抗氧化指标对沉积物中重金属总量和可提取态质量分数均有显著响应的为w(GSSG)与Cd,w(GSH)/w(GSSG)与Cr和Cd,OSI与Cr和Cd. 然而,w(GSH)/w(GSSG)和OSI只对w(T-Zn)有良好响应;GST只与w(TE-Cu)、w(TE-Zn)显著相关. 某些抗氧化指标对重金属总量和可提取态质量分数表现出不同程度的响应,因此,不能单独依据双壳类对重金属总量的生化响应特征来筛选用于沉积物综合毒性评价的生物标志物.      

太湖北部小流域沉积物重金属污染特征与评价

近几十年来重金属的沉积记录、来源及污染水平受到了广泛关注.为探明太湖北部小流域重金属的污染来源和环境质量状况,本研究分析了柱状沉积物中8种重金属（Mn、Cr、Zn、Cu、As、Pb、Ni和Co）含量.运用主成分分析法判定污染源,富集因子法表征重金属富集特征,通过熵权模糊模型对沉积物中重金属污染状况进行评价.结果显示,所有重金属含量均较高,高低依次为Mn > Cr > Zn > Cu > As > Pb > Ni > Co.其中Mn含量最高,为380.06~767.69μg/g.沉积物重金属污染的主要贡献因子为交通排放、农业污染和煤炭燃烧.As的富集指数最大（2.89~15.61）.其中77.59%的沉积层属于显著富集,受人类活动影响最为显著.熵权模糊综合评价结果表明,Cu（0.483）和As（0.352）的权重值最大,是沉积物中的首要污染物,且65.52%的沉积层重金属含量处于中度污染水平.     

商陆和烟草对锰胁迫的抗氧化响应研究

研究植物的重金属累积能力对于植物修复和植物冶金意义重大.Mn超累积植物商陆(Phytolacca americana L.)的耐性/累积机制至今还不清楚,为了研究商陆在Mn胁迫下的抗氧化酶作用,将萌发6周的商陆和烟草幼苗分别放入1 mmol·L~(-1)或3 mmol·L~(-1)的1/2 Hoagland营养液处理4 d,实验表明商陆叶片光合速率降低幅度显著低于烟草,而烟草MDA含量和电解质渗漏量增加幅度大于商陆.如1 mmol·L~(-1) Mn处理4 d后,与对照相比,商陆和烟草的光合速率分别降低13.3%和75.5%;烟草MDA含量和电解质渗漏量分别增加347.3%和120.1%,而商陆的MDA含量和电解质渗漏量没有明显增加,表明Mn胁迫对超累积植物引起的氧化损伤明显低于非累积植物.随着Mn处理浓度的提高和时间的延长,2种植物叶片SOD和POD活性均迅速增加,其中商陆SOD活性的增加幅度大于烟草;另外,商陆CAT活性持续上升,而烟草CAT活性显著下降.如在1 mmol·L~(-1) Mn处理下,商陆SOD、POD和CAT活性分别提高161.1%、 111.3%和17.5%;烟草SOD和POD提高55.5%和206.0%,而CAT下降15.6%,表明商陆的抗氧化酶,特别是CAT,能够有效地清除Mn毒产生的自由基.这些结果说明抗氧化酶的抗氧化能力是重金属累积植物商陆的Mn耐性机制之一.     

Response of antioxidase in viscera of Pagrosuma Major larvae to water soluble fraction of hydrocarbons in No.0 diesel oil

ＩｎｔｒｏｄｕｃｔｉｏｎＡｑｕａｔｉｃｆａｒｍｓｌａｒｇｅｒｔｈａｎ 1 4ｋｍ2 ａｒｅｌｏｃａｔｅｄｉｎｔｈｅｎｏｒｔｈｅｒｎｐａｒｔｏｆＷｅｓｔＨａｒｂｏｒ,ＸｉａｍｅｎＭｕｎｉｃｉｐａｌｉｔｙｏｆＣｈｉｎａ.Ｔｈｅｓｅｆａｒｍｓａｒｅｕｎｄｅｒｇｒｅａｔｅｎｖｉｒｏｎｍｅｎｔａｌｓｔｒｅｓｓｏｗｉｎｇｔｏｒａｐｉｄｅｃｏｎｏｍｉｃｄｅｖｅｌｏｐｍｅｎｔ.Ｉｎｒｅｃｅｎｔｙｅａｒｓ,ｄｅｔｅｒｉｏｒａｔｉｎｇｆｒｅｓｈｗａｔｅｒｆｉｓｈｅｒｙ,ｃｏｎｃｏｍｉｔａｎｔｗｉｔｈｉｎｃｒｅａｓｉｎｇｍｏｒ…     

舟山近岸海域沉积物中重金属的生物有效性研究

对舟山附近海域沉积物中的酸可挥发性硫化物（AVS）、同步提取重金属（SEM）和5种重金属的分布进行了调查,并用（SEM-AVS）差值法对上述重金属的生物有效性进行了研究。结果表明,该海域表层沉积物中AVS和SEM含量均较低,AVS含量范围为0.005~4.21 μmol/g,平均含量为0.546 μmol/g,SEM含量范围为0.3356~1.614 μmol/g,平均含量为0.7998 μmol/g;表层沉积物中Cu、Pb、Zn、Cr和Cd的平均含量分别为24.65×10-6、27.21×10-6、114.5×10-6、58.26×10-6和0.142×10-6。（SEM-AVS）差值法的结果表明除5个站位外,其余站位沉积物中重金属对生物可能具有中等毒性。     

Study on the sensitivity to cadmium of marine fish Salaria basilisca（Pisces： Blennidae）

The present study tested the sensitivity of Salaria basilisca to water-cadmium (Cd) contamination. For this purpose, liver somatic index (LSI), Cd concentrations and the activities of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured in the liver of S. basilisca exposed to Cd-contaminated water (2 mg Cd/L as CdCl2) for 14 and 28 d. The results showed that the LSI decreased significantly after 14 and 28 d of Cd-exposure. Cd bioaccumulation in the liver resulted in an increasing uptake up to 42 g/g dry weight after 28 d of exposure. Activities of CAT and SOD were significantly increased with increasing exposure time. A significant increase in GSH-Px activity, under Cd influence, was observed during 14-day exposure period (p < 0.0001). However, a significant decrease (p < 0.05) in this activity with respect to control fish was registered after 28 d of Cd-exposure. These results showed that Cd accumulation in the liver of S. basilisca could induce oxidative stress as demonstrated by changes in the antioxidant enzyme activities. Results also emphasized that S. basilisca may considered as a sensitive species to Cd exposure.