首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 578 毫秒
1.
The objective of this study was to investigate the effects of commercial formulation of herbicide 2,4-D on metabolic parameters, acetylcholinesterase (AChE) activity and liver histological evaluation of silver catfish (Rhamdia quelen) exposed for 96 h. AChE activity increased in brain (600 and 700 mg L−1) and decreased in all concentrations tested in muscle tissue. Hepatic glycogen was reduced after 2,4-D exposure ranging from 47.67% (400 mg L−1) until 59.3% (700 mg L−1). Hepatic tissue showed lactate reduction at all 2,4-D concentrations tested and glucose was reduced only at 700 mg L−1. In the highest concentration tested hepatic glycogen and glucose reduced instead plasma glucose levels increased. White muscle tissue showed glycogen reduction in fingerlings exposed to all herbicide concentrations and glucose reduction at 700 mg L−1. Muscle lactate levels increase at all 2,4-D concentrations tested. Vacuolation of hepatocytes and changes in its arrangement cords were observed by histologic analysis in group treated with 700 mg/L of 2,4-D. These results suggest that silver catfish exposed to concentrations of 2,4-D near of CL50 showed metabolic and histological response to compensate some stress caused by herbicide exposure. Taken together parameters measured can be used as biomarkers to monitor herbicide contaminated water.  相似文献   

2.
Organophosphothionate insecticide fenitrothion is known as potential toxic pollutant contaminating aquatic ecosystems. The effects of fenitrothion were studied to determine the 96 h LC50 value on Nile tilapia (Oreochromis niloticus) and investigate histopathological responses of fish exposed to sublethal fenitrothion concentrations. Data obtained from the fenitrothion acute toxicity tests were evaluated using the Probit Analysis Statistical Method. The 96 h LC50 value and 95% confidence limit for Nile tilapia (58.70 ± 6.97 g) was estimated as 0.84 (0.68-1.15) mg/L. Behavioral changes were observed closely during the acute toxicity test. The bioassay experiments were repeated three times and static test method was used. Some fish exposed to 96 h 0.1, 0.5 mg/L fenitrothion concentrations showed histopathological alterations in the gills, liver, kidney, brain and testes. Severely deformations were observed at 0.5 mg/L fenitrothion on the gills lamella such as hyperemia, epithelial hyperplasia, fusion and telangiectasis, in the liver tissue such as cloudy swelling, hydropic degenerations and lipid infiltration. In addition hyperemia and hemorrhage observed in kidney tissue and hyperemia was determined in brain tissue.  相似文献   

3.
The biological effects of two important medicinal plants, Artemisia annua L. and Achillea millefolium (L.) (viz, mortality, growth, and feeding indices as well as enzyme and non-enzymatic activities) were studied on small white Pieris rapae L a deleterious pest of cruciferous plants under controlled conditions (16:8 h L:D at 25 ± 1 °C and 65 ± 5% RH). The LC50 and LC25 values were 9.387% and 3.645% for A. annua L. and 4.19% and 1.69% for A. millefolium (L.), respectively. At the lowest concentration (0.625%), the deterrency was 29.826% and 44.185% for A. annua L. and A. millefolium (L.), respectively. Feeding indices were variously affected with changes in a number of parameters and an increase in larval and pupal duration. The activity level of alkaline phosphatase increased sharply while alanin and aspartate aminotransferases showed a sharp decrease. For non-enzymatic compounds, the amount of glucose and uric acid increased, but total protein and cholesterol decreased. These results indicate that these two medicinal plants might possess potential secondary metabolites that may be useful for controlling potential insect pests.  相似文献   

4.
Experiment was carried out to determine the median lethal concentration (LC50) of fenvalerate to Labeo rohita fingerlings. After determining the LC50 value of fenvalerate, a sub-lethal concentration (1/3rd of LC50) of fenvalerate was exposed for 15 days. Significant alterations in SOD (P < 0.05) activity of liver and gill was observed due to fenvalerate. Catalase activity in gills of fishes was also affected significantly (P < 0.05). WBC, NBT and Hct values were reduced significantly in fenvalerate exposed fishes as compared to control group, whereas blood glucose level showed higher values in fenvalerate exposed group. Serum total protein and albumin were also reduced significantly as a result of fenvalerate exposure. Significant increase in the serum GOT, serum GPT, creatinine, triglyceride and serum ACP was noticed after 15 days of fenvalerate exposure. Results indicated that short term exposure of fenvalerate can induce biochemical and haematological alterations causing stress to L. rohita fingerlings.  相似文献   

5.
Concerns have been raised that the amphibian larval stages are particularly at risk and may be vulnerable to adverse effects of pesticides. The present study reports acute toxicity of cypermethrin at 24, 48, 72 and 96 h through static renewal bioassay test for Duttaphrynus melanostictus. The LC50 values were 5.15, 4.55, 3.95, and 3.34 μg/L for 24, 48, 72, and 96 h respectively. At sublethal concentration (0.33 μg/L) behavioral, morphological and biochemical changes were studied. The behavioral and morphological anomalies observed in the present study are typical signs of cyano pyrethroid poisoning. Significant changes were observed in total, soluble, and structural proteins. The depletion of all the protein fractions observed in this investigation led to progressive protein oxidation and catabolism of proteins. Decreased protein level has resulted in a marked elevation of free amino acid levels at all time intervals. The induction of catalase, glutathione-S-transferase activities and elevation in the levels of hydrogen peroxide, reduced glutathione, and malondialdehyde eventually lead to oxidative damage of biomolecules, showing that the generation of reactive oxygen species and oxidative stress are involved in the toxicity induced by cypermethrin. Indicating increased susceptibility of tadpoles. Thus, an exposure to cypermethrin at sublethal concentration had catastrophic effect on tadpoles of D. melanostictus.  相似文献   

6.
Of the huge annual worldwide production (500,000 MT in 1997) of alkylphenol polyethoxylates (APEs) that are widely used as nonionic surfactants and anti-oxidants in variety of products, 60% ends up in water bodies. They undergo biodegradation to form octyl-, butyl-, and nonyl-phenols. This experiment evaluated effects of 4-tert-butyl phenol (4-TBP) in Cyprinus carpio, a projected candidate species in sewage fed fisheries. The 96th h LC50 of 4-TBP was found to be 6.9 mg/L. Fishes were treated with 1/10th (0.69 mg/L), 1/5th (1.38 mg/L), and 1/3rd (2.3 mg/L) dose of LC50. Whereas there was significant (P < 0.01) decrease in alkaline phosphatase [EC 3.1.3.1] and aspartate aminotransferase [EC 2.6.1.1] activity; alanine aminotranferase [EC 2.6.1.2] and acid phosphatase [3.1.3.2] (except decrease at 1/10th dose of LC50) activity, vitellogenin production in muscle and hepatic- and reno-somatic indices were increased compared to control. With all the dose levels tested, testicular-somatic index (testis size) was reduced (P < 0.01) and histo-architectural changes in testicular and liver tissue were found even in group given 1/3rd dose of LC50.  相似文献   

7.
Endosulfan is an organochlorine pesticide widely used in agriculture and hence finds its way into natural water bodies, thus affecting aquatic life. The purpose of this study was to determine LC50 of endosulfan (99%; α:β ratio of 7:3) in Tilapia, Oreochromis mossambicus and study its effect on anti-oxidative enzymes (superoxide dismutase, glutathione-S-transferase and catalase), immuno-hematological profile (RBC, WBC, Hb, serum protein, albumin-A, globulin-G, A/G ratio, phygocytic activity as indicated by nitroblue tetrazolium reduction, serum cortisol and serum lipid peroxidation) and neurotransmitter acetylcholine esterase enzyme activity. The LC50 value at 96 h and 95% confidence limit for tilapia (46.78 g) was estimated as 3.6 μg/L. Activities of anti-oxidative enzymes, immuno-hematological profile, blood glucose and neurotransmitter activity was significantly influenced (P < 0.01) in dose dependent manner. This was reflected in the behavior of fish that was altered from normal during acute toxicity.  相似文献   

8.
Diethyl phthalate (DEP) enter into aquatic environment from industries manufacturing cosmetics, plastic and many commercial products and can pose potential fish and human health hazard. This experiment evaluated effects of DEP in adult male (89 g) common carp (Cyprinus carpio) by exposing them to fractions of LC50 (1/500-1/2.5) doses with every change of water for 28 days. Vitellogenin induction metabolic enzymes, somatic indices and bioaccumulation were studied on 7th, 14th, 21st and 28th day. The 96th hour LC50 of DEP in fingerlings was found to be 48 mg/L. Compared to control, except increase (P < 0.01) in alkaline phosphatase activity (EC 3.1.3.1) and liver size, there was decrease (P < 0.01) in activity of acid phosphatase (EC 3.1.3.2), aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2) and testiculosomatic index following exposure to 1, 5 and 20 ppm DEP. Significant (P < 0.01) dose dependant vitellogenin induction was observed with exposure of fish to 0.1, 1 and 5 ppm DEP. The bioaccumulation of DEP in testis, liver, brain, gills and more importantly in muscle tissues of fish increased significantly (P < 0.01) with increase of dose from 1 to 5 ppm. Significant interaction (P < 0.01) of dose and duration of exposure indicated that exposure period of a week to two was sufficient to bring about changes in quantifiable parameters studied. Fish exposed to 20 ppm DEP became lethargic and discolored during onset of the 4th week. This is the first report describing metabolic changes and vitellogenin induction following exposure of C. carpio to DEP dose that is as low as 1/500th fraction of LC50.  相似文献   

9.
Four extracts of Arisaema erubescens tubers by acetic acetal (AAE), benzinum (BZE), n-butanol (NBE) and chloroform (CFE) were obtained to evaluate their molluscicidal activities against the snail Oncomlania hupensis. The responses of choline esterase (ChE), alkaline phosphatase (ALP), esterase (EST), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) to the extracts (NBE) were also investigated. In the four extracts (AAE, BZE, NBE and CFE), NBE showed the highest toxicity on the snails after 48 h exposure. NBE also showed the time- and concentration-dependent effect, for example, the LC90 values of the NBE were decreased from 365.5 mg/L (24 h) to 36.4 mg/L (96 h). At the end of exposure to NBE (LC50 concentration), the activities of ChE and ALP in snail tissues (cephalopodium and liver) decreased significantly. Isozyme electrophoresis profiles indicated that responses of isozymes (EST, SOD and GSH-Px) to NBE were more intense in liver than in cephalopodium. After 72 h exposure to NBE, the EST activity in snail liver decreased and some enzyme bands (EST1 and EST4) disappeared. But the activities of SOD 1 and GSH 2 in liver increased after 48 h exposure. The results indicated that NBE was the highest toxic component in the four extracts. The decline of the detoxification ability and the oxidative damage in snail tissues might be the main reason for the molluscicidal activities.  相似文献   

10.
In search for new local plant molluscicides for the control of the vectors of schistosomiasis, we compared the molluscicidal action of the extract of Ginkgo biloba sarcotesta by benzinum (EGSB) to that of arecoline (ARE) and niclosamide (NIC) against Oncomelania hupensis snails. NIC showed the highest toxicity on snails with 24 h LC50 vales of 0.12 mg/L and LC90 of 0.98 mg/L, while the LC50 and LC90 of EGSB were much lower than that of ARE. Sublethal in vivo 24 h exposure to 40% and 80% LC50 of NIC, EGSB and ARE altered the activities of different enzymes in different body tissues of snails. EGSB could significantly inhibit Choline esterase (ChE), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP) and Malic dehydrogenase (MDH) activities both in the cephalopodium and liver. ARE could significantly cause a reduction in ChE, ALP activities in the cephalopodium and ChE, ALT, ALP, Succinodehydrogenase (SDH), MDH activities in the liver. NIC significantly altered activities of ChE, ALT, ALP, SDH, and MDH in the cephalopodium and ChE, ALT, ALP, SDH activities in the liver. All molluscicides could not affect Lactate dehydrogenase (LDH) activity in the cephalopodium and the liver. Maximum inhibition of ALT and MDH activities was found in the cephalopodium and liver of snails treated with 80% of 24 h LC50 of EGSB. However, NIC and ARE caused maximum reduction in ALP and SDH activities, respectively. The results indicated that molluscicidal action of EGSB was different to that of ARE and NIC in some extent.  相似文献   

11.
Rice (Oryza sativa), a relatively tolerant species, and early watergrass (Echinochloa oryzoides; EWG), a relatively susceptible species, were exposed to 14C-labeled clomazone to determine accumulation, biotransformation, and mass balance. On a total mass basis, rice absorbed more clomazone than EWG (p < 0.05), but on a nmol/g basis, there was no significant difference between the two species (p > 0.05). Rice contained more extractable 14C residues (7.7 ± 0.5 vs. 4.8 ± 0.5 nmol in rice vs. EWG, respectively; p < 0.5), but the concentration in EWG was significantly higher (4.2 ± 0.5 vs. 1.8 ± 0.1 nmol/g in EWG vs. rice, respectively; p < 0.01). More metabolized residue was measured in EWG compared to rice (84.1% vs. 67.9%; p < 0.01). Both species produced hydroxylated forms, β-d-glucoside conjugates, and several other unidentified polar metabolites, but EWG generally produced higher metabolite concentrations. The concentration of the suspected active metabolite, 5-ketoclomazone, was significantly higher in EWG vs. rice (21 ± 2 vs. 5.7 ± 0.5 pmol/g, respectively; p < 0.01). Differences in sensitivity to clomazone between rice and EWG appear to be due to differential metabolism, but in this case the more susceptible EWG qualitatively and quantitatively metabolized more clomazone than the more tolerant rice. This is consistent with the action of a metabolically activated herbicide. This metabolic difference could be exploited to develop herbicide safeners for use with clomazone.  相似文献   

12.
  相似文献   

13.
The results showed that survival rates of Biomphalaria alexandrina snails, reproductive potential and hatchability of eggs were evaluated post exposure to Basudin, Selecron and Colchicine. As well, DNA and RNA changes in the cells of ovotestis-digestive gland complex of treated snails were estimated. The current molluscicide Bayluscide was used as a reference compound.The pesticide Selecron proved to be more toxic to B. alexandrina snails than Basudin and Colchicine. Juvenile snails were dead post 3 weeks of exposure to the sublethal concentration LC0 of either Selecron or Basudin, while 26.75% of snails still alive at Bayluscide treatment. In addition, exposure of adult snails to LC0 of Selecron for 24 h/week for 4 weeks markedly reduced their reproductive rate (R0) by 89.9%. Moreover, snails’ eggs failed to hatch post 24 h of exposure to LC90 of either Selecron, Basudin or Bayluscide. Electrophoretic analysis indicated a decrease in the molecular weight of intact DNA in the ovotestis-digestive gland complex of snails treated with 250 ppm of Colchicine and LC25 of Selecron, as it scored 1.2 and 76 bp, respectively, compared to 166.46 bp for control group, while the vice versa was recorded for RNA intensity. It was concluded that the tested pesticides have deleterious effects on snails’ reproductive rate, their eggs and the intensities of DNA and RNA in their ovotestis-digestive gland complex. Therefore, it is expected that reaching of such pesticides to snails’ habitats in water courses during plant pests control could minimize the population density of the snails intermediate hosts of schistosomiasis, hence probably interrupt and reduce the transmission of this parasite.  相似文献   

14.
Nile Tilapia (Oreochromis niloticus) juveniles were exposed to different concentrations of Folidol 600® in static toxicity tests. The 24, 48, 72 and 96 h LC50 values of Folidol 600® to O. niloticus were 17.82, 8.91, 4.00 and 2.70 mg L−1, respectively. The values of hematological parameters increased, and inhibition of cholinesterases activity (AChE, BChE and PChE) in plasma of fish exposed to the higher concentrations of pesticide reached 94%. Furthermore, the exposure of Tilapia to Folidol 600® caused an increase of 4%, 20% and 38.4% in oxygen consumption at 0.1, 0.5 and 1.0 mg L−1, respectively. However, exposure to 2.5, 5.0 and 10 mg L−1 caused a decrease of 33.6%, 35.2% and 42.4% in oxygen consumption relative to the control. The ammonium excretion of fish exposed to 0.0, 0.1, 0.5, 1.0, 2.5, 5.0 and 10.0 mg Folidol 600®/L was 0.12, 0.18, 0.30, 0.33, 0.37, 0.36 and 0.33 μg/g/min, i.e., 50%, 150%, 175%, 208%, 200% and 175% increase, respectively, relative to the control.  相似文献   

15.
Deltamethrin, a synthetic pyrethroid pesticide contaminating aquatic ecosystems as a pollutant, was investigated in the present study for toxic effects on embryos and larvae of common carp, Cyprinus carpio as a model. The control and five test experiments were repeated five times. The water temperature in the experimental units was kept at 24 ± 1 °C. The number of dead embryos significantly increased in response to deltamethrin concentrations 0.005, 0.05, 0.5, 5, 25, and 50 μg L−1 (p<0.05 for each cases). Dose-response decreases in hatching success were recorded as 75.2, 64.6, 47.4, 26.0, 14.4, and 9.0%, respectively. The lowest concentration of deltamethrin (0.005 μg L−1) produced a significantly decrease in number of dead larvae compared to control group (p<0.05). With increasing deltamethrin concentrations, the larvae exposed duration 1-48 h significantly increased the number of dead larvae (p<0.05 for each cases). The 48 h LC50 values (with 95% confidence limits) of deltamethrin for common carp embryos and larvae were estimated as 0.213 (0.103-0.404) and 0.074 (0.011-0.260) μg L−1, respectively. The results provide evidence that deltamethrin pollution may have an adverse effect on the reproduction and development of carp, which should be considered when this chemical is used in agricultural areas near aquatic ecosystems.  相似文献   

16.
Huanong AVM is a novel nematicide, which was synthesized from avermectin by selective oxidization of the hydroxyl group at C-4, followed by the reaction with glacial acetic acid. Effects of Huanong AVM on Bursaphelechus xylophilus are reported in this paper. Huanong AVM had strong nematicidal activity against B. xylophilus, with LC50 values of 14.84 μg/mL, 12.49 μg/mL and 11.05 μg/mL, respectively, at 48 h, 72 h and 96 h after treatment. The proteins that responded to Huanong AVM were identified by proteomic analysis. 2-DE analysis revealed eighteen differentially accumulated protein spots. Five spots were successfully identified by MS analysis, and three Huanong AVM induced proteins were annotated in the database as LEVamisole resistant family member (lev-11), ACTin family member (act-4) and Hypothetical protein Y52B11A.10. Two Huanong AVM-up-regulated proteins were assigned as PIP Kinase family member (ppk-3) and Hypothetical protein B0432.6. These proteins are involved in signal transduction, maintaining cytoskeletal structure and LEVamisole resistance. These results point to pathways that are important for the mode of the action of Huanong AVM on B. xylophilus.  相似文献   

17.
Imidacloprid (IMI) microcrystals were directly encapsulated with nature polysaccharides chitosan (CHI) and sodium alginate (ALG) through layer-by-layer (LbL) self-assembly. The coated colloids were characterized using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The in vitro controlled release pattern of IMI through the PE diffusion barrier was studied using a diffusion cell assembly at physiological pH of 7.4. Photocatalysts were characterized by Brunauer-Emmett-Teller (BET) surface area and SEM. The adsorption and photocatalytic activities of photocatalysts were evaluated by isothermal adsorption and IMI degradation under UV light and natural light illumination. The toxicity of the photodegradable insecticide was evaluated against the adult stage of Martianus dermestoides. The results showed that thermodynamically stable IMI microcrystals were obtained by association and had a mean length of 7 μm and a ζ-potential of −37.5. The drug loading and encapsulation efficiency were 56.15 ± 0.96% and 81.57 ± 0.96%, respectively. The polysaccharide capsules prolonged the release time of the encapsulated IMI crystals. Among the photocatalysts, SDS/Ag/TiO2 had the highest photocatalytic activity. Toxicity of the novel 50% nano-SDS/Ag/TiO2-IMI was higher in the adult stage compared to the 95% IMI as indicated by the lower LC50 value.  相似文献   

18.
Study was carried out to investigate the chronic response of cyanobacteria, Anabaena fertilissima to chlorophenoxy herbicide 2,4-dichlorophynoxyacetic Acid (2,4-D) ethyl ester at different concentrations 15, 30 and 60 ppm. The influence of 2,4-D on growth (pigments), release of metabolites such as carbohydrates, protein, amino acid, phenols and nitrate reductase and glutamine synthetase activities was analyzed. The test concentrations caused a concentration-dependent decrease in pigments. Depletion in carbohydrate and protein content was registered with rise in herbicide concentrations. However, phenols were found to rise with increased herbicide concentrations but amino acids were reported to decline. The inhibition of nitrate reductase and glutamine synthetase activity was also concentration-dependent and showed more sensitivity for substituted phenoxy herbicide. This study therefore suggests that decrease in metabolite content and enzyme activity can be used as a signal of herbicide toxicity in cyanobacteria.  相似文献   

19.
The present study was conducted to determine the 96 h-LC50 of benomyl to the Nile tilapia, Oreochromis niloticus and to investigate the biochemical or hematological indices of blood and the alterations in the antioxidant enzymes of this fish in response to sublethal concentrations of benomyl. Fish weighing 71.61 ± 12.05 g were used in this study; they were subjected to fasting for 4 weeks before treatment. An aqueous solution of benomyl (0, 0.5, 1, 2, 4, 8, and 16 mg L−1) was administered for 96 h to determine the LC50. The 96 h-LC50 value of benomyl was 4.39 (3.23-5.60) mg L−1 in the present study. For 5 weeks, the aqueous solution of benomyl (0, 100, 200, and 400 μg L−1) was administered to investigate its effect on the hematological parameters and antioxidant enzymes. The predominant hematological findings in fish exposed to benomyl were as follows: no significant change in the Hb (g dL−1) level, MCV (μm3), MCH (pg) and MCHC (%) as compared to the control. Benomyl exposure led to greater increases in the GPT, GOT (Karmen-unit), LDH (Wroblewski unit), total cholesterol, Fe, and Ca (mg dL−1) values, whereas the levels of ALP (KA unit), total protein, triglyceride, albumin, and Mg (mg dL−1) did not increase. Benomyl increased the in vivo HSI (%), GST (nmol min−1 mg protein−1), and SOD (U mg protein−1) values in the fish livers in the test group, unlike those in the control group for 5 weeks. At concentrations higher than 100 μg L−1, benomyl affected the GST and SOD levels of Nile tilapia in a dose- and time-dependent manner. The present findings suggest that the in vivo hepatotoxicity associated with benomyl may, in part, result from the hematological index, and antioxidants may provide limited protection against benomyl toxicity.  相似文献   

20.
Diazinon is commonly used for pest control in the agricultural fields surrounding freshwater reservoirs. So this study was conducted to determine the acute toxicity of this organophosphorous pesticide, contaminating aquatic ecosystems as a pollutant, and its effects on behavior, and some hematological parameters of fingerling European catfish, Silurus glanis. Diazinon was applied at concentrations of 1, 2, 4, 8, 16, 32, and 64 mg L−1. The water temperature in the experimental units was kept at 16 ± 1 °C. The number of dead fishes significantly increased in response to diazinon concentrations 2-64 mg L−1 (p < 0.05). With increasing diazinon concentrations, the fishes exposed duration 1 to 96 h significantly increased the number of dead fishes (p < 0.05 for each cases). The 1, 24, 48, 72, and 96 h LC50 values (with 95% confidence limits) of diazinon for fingerling European catfish were estimated as 14.597 (12.985-16.340), 12.487 (11.079-14.471), 8.932 (7.907-10.348), 6.326 (no data because of p > 0.05), and 4.142 (no data because of p > 0.05) mg L−1, respectively. Compared to the control specimens, fish after an acute exposure to diazinon was significantly lower erythrocyte, leukocyte, hemoglobin, hematocrit, MCV, MCH, and MCHC values (p < 0.05). In addition, it was also showed a significantly negative correlation between these hematological parameters and exposure times of diazinon (p < 0.01).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号