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1.
Although fish feed supplemented with Chinese parsley (CP), Coriandrum sativum, does not affect the health of rainbow trout Oncorhynchus mykiss, it has the remarkable effect of reducing the uptake of Cd (12–17% compared with controls without CP). Here, we measured the change in the amount of metallothionein (MT) in the liver and kidney using gel permeation chromatography-high-performance liquid chromatography (TSK GEL SW 3000 column). The increase in MT content over time in the Cd-fed groups corresponded to the change in Cd accumulation. Gel permeation was performed with soluble fractions from the fish liver and kidney, and changes in the Cd, Cu, and Zn concentrations over time for each fraction, and the relationship between the form of Cd that accumulated in tissues and its toxicity were measured. A nontoxic MT fraction of 7,000 Da and a high-molecular-weight fraction of approximately 60,000 Da were isolated from the soluble fractions. The induction of nontoxic MT–Cd was higher in the CP-supplemented groups than in the control groups. The synergetic actions of several compounds in CP may contribute to bind MT, thereby preventing accumulation of harmful heavy metals and essential metals in fish.  相似文献   

2.
Three different commercial fish species Odontesthes bonariensis, Rhamdia quelen and Oreochromis niloticus and fish feed were collected from four aquaculture farms. Heavy metal (Cd, Cr, Cu, Fe, Mn, Pb and Zn) and arsenic concentration were determined by inductively coupled plasma–optical emission spectrometry (ICP‐OES) in muscle, liver, gonad, skin, scale and fat from fish and in feed diets. Arsenic concentration was found in different tissues differing between species and within O. bonariensis. Cd was differentially accumulated in liver in O. bonariensis and R. quelen; however, in O. niloticus Cd was found in muscle and scales. Higher concentrations of Cr were determined in skin and scales of O. bonariensis and O. niloticus. Cu, Fe, Mn and Zn were found in all tissues being Cu and Fe concentrations higher in liver. Mn was differentially accumulated in O. bonariensis scales, however in R. quelen no significant differences were found and in O. niloticus liver was the main accumulation tissue. Zn concentration was higher in gonad, skin and liver from R. quelen and O. bonariensis, and in O. niloticus the highest concentration was found in scales. All the results were below the international limits for food safety except for the concentration of Cd in muscle and scales of O. niloticus.  相似文献   

3.
It is of crucial importance to study on the biomarkers types to assess the specification of the pollutants and health status of marine ecosystems in environmental evaluation projects. In this respect, total metallothionein biosynthesis and mercury bioaccumulation in the liver and gills under acute mercury exposure were investigated in fish, Scat (Scatophagus argus). Spotted scat was exposed to different mercury concentrations (0, 10, 20, 30) for 24, 48, 72 h. Total MT levels were determined by enzyme-linked immunosorbent assay (ELISA) method. Mercury contents were determined through cold vapor atomic absorption spectrometry (CVAAS). Induction of MT during exposure was tissue specific, displaying different response pattern in gills and liver. Mercury accumulated in liver much higher than in gills and the latter also showed lower MT level (P < 0.05). MT biosynthesis in liver showed a significant (P < 0.05) increase after exposure to different mercury concentration with increase in exposure time, whereas total MT content did not significantly (P > 0.05) change in gills except for 72 h exposure at 30 μg l−1. Nonetheless, the relationship between MT biosynthesis and Mercury bioaccumulation in both tissues was significant (P < 0.05). The results suggest that this form of MT in S. argus was Hg inducible and could be extended as a biomarker of mercury pollution in marine ecosystems.  相似文献   

4.
This research was designed to study Sparus aurata (sea bream) biotransformation and detoxification responses to acute exposure to cadmium (Cd). Sexually immature gilthead sea bream were treated by intraperitoneal injection of Cd chloride (200 μg kg−1) for 6, 12, 24 and 48 h. Cd accumulation was quantified in sea bream liver by graphite furnace atomic absorption spectroscopy after the various exposure periods. The following biological responses were measured: (1) ethoxyresorufin-O-deethylase (EROD) activity as phase I biotransformation parameter, (2) liver glutathione-S-transferase (GST) activity as a phase II conjugation enzyme and metallothionein (MT) content as specific response to Cd contamination. Cd bioaccumulation in the liver resulted in an increasing uptake up to 10.3 μg g−1 wet weight after 48 h of exposure. EROD showed a significant activation only after 6 h exposure and a return to control levels after 12 h. GST revealed significant activation starting from 12 h exposure. MT accumulation in liver showed the same behavior as GST activation.  相似文献   

5.
Metal pressure under farm conditions was examined on the gill and muscle tissues of farmed Sparus aurata and compared with their wild counterparts (Sparus aurata, Trachurus trachurus, Mullus barbatus). Al, Mn, Cd, Co, Cr, Cu, Ni, Pb and Zn accumulation amounts in gill tissue of farmed fish were 28.821, 37.620, 0.136, 0.300, 3.730, 2.441, 3.222, 2.474 and 127.494 mg/kg respectively. Among them, Cd, Cr, Cu and Pb concentrations in gill tissue of farmed fish were higher than that in wild fishes. Metal depositions in muscle tissue of farmed fish were far below that in the gill tissue. The accumulated Al (6.700 mg/kg) in the muscle tissue of farmed fish was higher than in wild ones. The results showed that metal accumulation levels (especially Cd, Cr, Cu and Pb) in the gill tissue of farmed fish indicate metal pressure under captive conditions. Furthermore, the calculated hazard index (HI) and total hazard index (THI) of the considered elements in the edible part of farmed fish were below the level considered safe, which elucidates that farmed fish do not pose any threat to the human consumer in terms of metal toxicity.  相似文献   

6.
Cadmium (Cd) compounds are widely distributed toxic environmental and industrial pollutants, and they may bring danger to growth and development of aquatic organisms. In China, the Oujiang color common carp, Cyprinus carpio var. color, is a very important fish, from an economic point of view, and is well used for fish culture in paddy fields. The purpose of this study was to show the low concentrations of cadmium-induced oxidative stress response and DNA damage in the livers of Cyprinus carpio var. color. Superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH) in liver were measured after exposure to Cd levels (0.41, 0.52, 0.69, 1.03 and 2.06 mg/L, respectively) for 7 days and compared with the control groups. DNA damage, including indicators of damage percentage, DNA tail length (TL) and DNA tail moment (TM) were also analyzed by comet assays. Results showed that MDA and GSH levels in all treatment groups increased significantly relative to the controls (P < 0.01). Treatment with Cd at concentration of 0.41 mg/L increased SOD activity, while treatment with Cd at concentrations >0.41 mg/L inhibited SOD activities. DNA damage percentage, TL and TM also significantly increased when the Cd level was >0.41 mg/L. Positive correlations were also found between DNA damage levels and MDA levels (r = 0.74 for DNA damage percentage, r = 0.83 for TL, r = 0.84 for TM; P < 0.01 for all) as well as between GSH and MDA levels (r = 0.77, P < 0.01). These results strongly suggested that Cd-induced DNA damage in the livers of Cyprinus carpio var. color was due to lipid peroxidation and oxidative stress.  相似文献   

7.
The present study examines the pattern of accumulation of cadmium (Cd) and its biochemical effects on selected tissues of a variety of African catfish (Clarias gariepinus), after exposure to various doses of Cd. The results obtained indicate that at the end of 21 days of exposure, the total tissue organ cadmium concentration followed the pattern kidney > gill > liver > muscle for each of the exposure concentrations. The levels of Cd in these organs were higher than those in ambient water. Moreover, while the rate of uptake of Cd increased with time in the kidney, liver and muscle, it decreased in the gill. Superoxide dismutase (SOD) was significantly elevated only in the kidney of catfish treated with 0.2 and 0.4 ppm of Cd for 7 days compared with the control. Conversely, gill SOD was significantly decreased in the same concentrations of Cd-treated catfish relative to the control. Statistically similar levels of SOD were observed in the liver, brain and muscle with all the treatments after the same duration of treatment. In the fish exposed for 21 days, SOD activity was significantly decreased in the kidney with a corresponding increase in lipid peroxidation (LPO), but it manifested only with the 0.2- and 0.4-ppm Cd treatment relative to the control. In the liver, however, Cd exposure significantly increased SOD in the 0.2- and 0.4-ppm treatments of the same duration. In conclusion, the present study indicates that the accumulation of Cd and its effect on SOD and LPO in C. gariepinus is dependent on concentration, tissue and time  相似文献   

8.
The objective of this study was to determine whether metallothionein (MT) expression was related to Cd accumulation in hard clams (Meretrix lusoria). We cloned clam MT. Then a specific primer for the hard clam was designed for MT mRNA measurements using real-time PCR. The hard clams were exposed to 50, 200, and 1000 μg/L cadmium (Cd) for 1, 3, 5, and 7 days, to determine the relationship between MT mRNA relative quantity (RQ) levels and Cd accumulation. The following results were obtained: (1) the cloned MT, consisting of 228 bp encoding a protein of 76 amino acids showed higher than 55% identity with the deduced amino acid sequence previously published for another bivalve. (2) Both MT mRNA expression and Cd accumulation appeared to be dose-responsive following cadmium treatment for 1, 3 and 5 days, respectively; however, no time-dependent responses were found. According to these results, MT mRNA expression levels can be used as an indicator to monitor the concentrations of Cd in aquaculture farms.  相似文献   

9.
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10.
Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0 mg/L Zn, 1.0 mg/L Cd, and 5.0 mg/L Zn + 1.0 mg/L Cd mixture for 7 and 28 days, and alterations in serum enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7 days while they increased at 28 days. Fish exposed to metals showed a decrease in cholinesterase activity at 7 days followed by a return to control levels at the end of the exposure period. The individual and combined effects of metals caused a decline in levels of Na+, Cl−, and Ca2+, especially at 28 days. K+ level increased at 7 days but it returned to control levels with increasing duration of exposure. This study indicated that the alterations in serum parameters may be a result of the target tissue (i.e., liver, gill, and kidney) damage and dysfunction induced by the metals and that these parameters can thus be used to assess the effects of metals on organisms.  相似文献   

11.
赤水河主要经济鱼类重金属含量及风险评价   总被引：2，自引：0，他引：2  
为了解赤水河鱼体重金属富集现状及其潜在的生态风险和食品安全,测定了赤水河茅台江段和赤水江段的黄颡鱼(Pelteobagrus fulvidraco)、蛇鮈(Saurogobio dabryi)和大口鲇(Silurus meriordinalis)肌肉和肝脏中的重金属含量。分别使用电感耦合等离子体原子发射光谱法测定Cu、Zn、Pb、Cd、Fe、Cr和Mn的含量,原子荧光光度法测定As和Hg的含量。结果表明:大口鲇肌肉中Cu、Zn、Pb、Cd、Fe、Cr和Hg的含量高于黄颡鱼和蛇鮈,3种鱼类肝脏中的重金属含量均高于肌肉。所有鱼体肌肉中的重金属含量均低于国家标准,但大口鲇肌肉中Pb和Cd的含量高于欧盟委员会标准。危害指数分析表明:赤水河野生鱼类食用的人体健康风险较小。重金属单因子污染指数的结果表明赤水河鱼体Pb和Cd的污染程度较高,赤水河存在潜在的重金属污染风险。  相似文献   

12.
Metal enrichment makes oyster considered to be an appropriate food source for trace elements, but excessive accumulation can threaten human health. Reproduction is an important biotic factor that affects the metal accumulation in oysters. However, the influence of continuous gonad development model on metal accumulation in some subtropical oysters is still unclear. The present study addresses the concentrations of trace metals and glycogen associated with the gonadal and somatic tissues throughout the reproductive cycle of diploid and triploid Crassostrea angulata cultured in Fujian, China. Cu, Zn and Pb contents of gonads were negatively correlated (p < 0.05) with gonadosomatic index (GSI). The correlation between Cd content and GSI was not significant. There was a positive correlation (p < 0.05) between GSI and Mn content in female gonads while the correlation was negative (p < 0.05) in males, indicating Mn plays an important role in gametogenesis of females. The effects of gonadal maturity and gender on metal accumulation in somatic tissue were not significant (p > 0.05). The concentrations of all metals in sterile triploids were not significantly different from those of the somatic tissue of diploids. Gonadal glycogen content showed a negative correlation with the GSI. However, somatic glycogen content was not affected by gonadal development, indicating that the energy consumed during gametogenesis comes mainly from recently ingested food rather than from energy stored in somatic tissue. The effects of the gonadal development on the metal accumulation in oysters varied according to the metal and tissue type.  相似文献   

13.
Concentrations of heavy metals, including Hg, Cu, Pb and Zn, in sediment and different organisms as well as the transference through the food web in a polyculture pond were investigated. The δ15N values of consumers showed a gradual enrichment with increasing trophic positions from the filter‐feeding bivalves (δ15N = 10.93 on average) to the predators (δ15N ≥ 12.59 for all crustacean and fish). Concentrations of heavy metals in sediments followed the decreasing order: Cu ≈ Zn > Pb > Hg, while in organisms, the order was Zn > Cu > Pb > Hg. Concentration of Cu was negatively related to the δ15N values of the animal tissues (P < 0.05), indicating the decrease in the Cu concentration with increasing trophic positions. Concentrations of Hg, Pb or Zn did not show significant relationship to the trophic positions. Food sources and feeding guilds of organisms might be more important factors determining the heavy metal concentrations in the body tissues of aquatic animals than their trophic positions.  相似文献   

14.
Trochophore and veliger are vulnerable pelagic larvae and susceptible to environmental toxicants, which are extremely crucial for the population renewal. Cu, Zn and Cd pollution are common elements in metal pollution in coastal areas. Though Pacific abalone is the main economic mollusc in China, its larval response to metals remains unclear. To understand this, the effect of Cu, Zn and Cd toxicity on malformation classification and respiratory metabolism of trochophore and veliger are analysed and measured in this paper. The 48 hr EC50 for abalone trochophore was (18.9 ± 1.0) μg/L for Cu, (65.1 ± 0.3) μg/L for Zn and (1,377.8 ± 68.9) μg/L for Cd respectively. The LC50 of veliger was (45.8 ± 0.9) μg/L for Cu, (50.0 ± 0.9) μg/L for Zn and (1,049.3 ± 37.6) μg/L for Cd respectively. Trochophore died with no shell at 128 μg/L Cu, yet remained alive with multiple broken‐shell bodies at 128 μg/L Zn and failed to form well‐developed shells at 20,480 μg/L Cd. All veliger died with complete shells at the mentioned concentrations. A self‐made device was used to study the effect on respiratory metabolism. The respiratory metabolism level was significantly fluctuating under Cu and Zn exposure and declined under Cd. The results indicated a decreasing order of the metal toxicity to trochophore and veliger as follows: Cu > Zn ? Cd. Cu and Zn were the main causes of shell abnormality, and Cd was less toxic. Moreover, the affected respiratory has a negative impact on further larval development.  相似文献   

15.
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16.
One isoform of the low-molecular-weight metal-binding protein metallothionein (MT) has been isolated from the liver of Atlantic cod by size-exclusion and ion-exchange chromatography. Cod MT contained 33% cysteine, no aromatic amino acids or arginine. As is the case for other piscine MTs, the N-terminus of cod MT lacked the asparagine in position 4 which is present in mammalian MTs. In addition, cod MT differed from all other vertebrate MTs described in that the N-terminal methionine was not acetylated. Antibodies were raised in rabbits against hepatic MT from cod by repeated injections of native protein mixed with adjuvant. Anti-cod MT antisera cross reacted with similarly-sized proteins in liver, brain, anterior kidney, posterior kidney, spleen, intestine, gills and ovaries. The putative MT in cod brain migrated differently to that of the other tissues in native gel electrophoresis. Intraperitoneally injected Cd (1 mg/kg) was nearly entirely associated with the MT-peak in hepatic and renal cytosols, whereas a single injection of Zn (10 mg/kg) resulted in increases in all cytosolic Zn pools of the liver and no apparent change in cytosolic Zn, Cu, Ni or Cd in kidney.  相似文献   

17.
Intraperitoneal injection of turbot with Cd induced the synthesis of a low molecular weight hepatic Cd-binding protein and a 500bp mRNA, which hybridised to a plaice metallothionein (MT) cRNA probe. The Cd-binding protein displayed cross-reactivity in a competitive ELISA with antiserum raised against rainbow trout MT and had the characteristic amino acid composition, metal stoichiometry and spectral characteristics of a Class I MT. Only one isoform was apparent on ion exchange chromatography. Southern blot analysis of DNA cleaved with four restriction enzymes suggested that only a single MT gene is present in turbot.In an established turbot fibroblast cell line, Cd induced MT mRNA and MT levels in a dose and time-dependent manner. MT was also induced by Cu, Hg and Zn but not Pb exposure. Physiological concentrations of glucocorticoids and sex hormones did not induce MT synthesis, although at high concentrations a positive response to corticosterone, dexamethasone, hydrocortisone or progesterone was observedin vitro indicating the possible presence of a functional steroid regulatory element in the fish MT gene.Abbreviations used AMP adenosine monophosphate - CHSE chinook salmon embryo - DMSO dimethyl sulphoxide - HPLC high performance liquid chromatography - KB kenacid blue - MT metallothionein - Mr molecular weight (kDaltons) - NR neutral red - PEG polyethylene glycol - RTH rainbow trout hepatoma - SDS sodium dodecyl sulphate - SSC 0.15M NaCl, 0.015M sodium citrate - TF turbot fibroblast  相似文献   

18.
The aim of the present study was to evaluate bioaccumulation of metals in various tissues of the freshwater fish Cyprinus carpio L. exposed to cadmium and copper (a xenobiotic and a microelement). The fish were subjected to short-term (3 h, Cd-S and Cu-S) or long-term (4 weeks, Cd-L and Cu-L) exposures to 100 % 96hLC50 or 10 % 96hLC50, respectively. Blood, gill, liver, head and trunk kidney were isolated weekly from 5 fish of each group for 4 weeks (post-short-term exposure and during long-term exposure). Atomic absorption spectrophotometry technique was applied to measure concentrations of metals (Cd and Cu) in fish tissues. Initial concentrations of copper in fish tissues were higher than levels of cadmium. Cadmium and copper levels increased in all tissues of metal-exposed fish. After short-term exposures (at higher concentration) and during long-term exposures (at lower concentration), similar changes in metal concentrations were observed. The values of accumulation factor (ratio of final to initial metal concentration) were higher for cadmium as compared to copper. Comparison of metal levels and accumulation factors in various tissues revealed that cadmium and copper showed very high affinity to head kidney of common carp (higher than to other tissues), but accumulation factors for cadmium in trunk, head kidney and liver were much higher than for copper. The concentrations of copper in organs of Cu-exposed fish increased only slightly and quickly returned to the control level, which shows that fish organism easily buffered metal level. On the other hand, concentrations of cadmium considerably increased and remained elevated for a long time which suggests that activation of mechanisms of sequestration and elimination of cadmium required more time.  相似文献   

19.
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20.
In this study, some biochemical changes of carp (Cyprinus carpio, Linnaeus 1758) tissues were investigated. Studies have been carried out on carp which have regional economical importance. Storage temperature and time are the most important factors that affect the quality of fish during sales. It was observed that the temperature varied between 9 and 12°C in sale conditions. In addition, we assumed the arrival time of the fish at the fish market to be 0 (zero) h. Biochemical analyses [malondialdehyde (MDA) levels and catalase activity] of carp tissues (muscle, liver, heart, spleen, brain) were carried out on fish which were held for 24 and 48 h, as well as on fresh fish (0 h). In addition, sensory analysis was conducted by a panel consisting of experienced judges of sensory evaluation. Statistically significant (P < 0.05) increases in MDA levels were found in liver, muscle, brain and spleen tissues when comparing the 0- and 24-h groups. But there was no statistically significant (P > 0.05) increase in MDA level in heart tissue of carp after 24 h. There was a statistically significant (P < 0.05) increase in MDA levels in muscle, spleen and heart tissues when comparing the 24- and 48-h groups. In the group examined at 24 h, it was observed that there were statistically significant differences from the 0 h group values (P < 0.05) for catalase (CAT) activity in muscle, brain, spleen and heart tissues. The decreases in CAT activity in liver and spleen tissues were found to be statistically significant (P < 0.05) between the group examined at 24 h compared with the group examined at 48 h. Carp maintained good quality during the selling conditions up to 24 h. This experiment deals with the effects of post-slaughter time and storage temperature on carp tissues. It is concluded that by considering the storage temperature (9–12°C) and storage time (post-slaughter) the product maintained acceptable quality up to 24 h. There was significant deterioration of sensory quality, as a result of changes in chemical constituents.  相似文献   

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