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1.
The goal of this study was to assess coastal marine pollution in the Mar Piccolo and Taranto Gulf (Ionian Sea, Southern Italy) by combining chemical and toxicological data in order to compare and integrate both approaches. Pollutants levels, traditionally, have limited ability to predict adverse effects on living resources. Moreover, in order to provide information on the ecological impact of sediment contamination on aquatic biota Numerical Sediment Quality Guidelines (SQGs) and sediment toxicity bioassays were carefully recommended. In this study ERL (effect range low)/ERM (effect range medium value) and TEL (threshold effect level)/PEL (probable effect level) guidelines have been used. Bioassays were performed with two species of amphipods Gammarus aequicauda and Corophium insidiosum, one species of isopod Idotea baltica and bivalve Mytilus galloprovincialis larvae. The TEL/PEL analysis suggested that, especially for stations 1 and 2, sediments in Mar Piccolo should contain acutely toxic concentrations of metals. In particular Hg content, in station 1, was about 17 times PEL value. 96 h LC50 and 48 h EC50 values were estimated for cadmium, copper and mercury in these species using the static acute toxicity test. M. galloprovincialis larvae was more sensitive than other species to all the reference toxicants tested (EC50 determined for cadmium copper and mercury were of 0.59, 0.11 and 0.01 mg/l respectively). Significant differences in sensitivity of species tested to all reference toxicants (ANOVA p < 0.001) were recorded. Bioassays with these species allowed to estimated sediment toxicity from the different studied sites. On the basis of results obtained a good agreement was reported between chemical data and response of the biological endpoints tested.  相似文献   

2.
The interest in the ecological relevance of risk assessments and, thus, in in situ bioassays has been increasing in the last years. The present study developed a time- and cost-effective in situ bioassay, aiming at obtaining, in a short period of time and with a minimum of resources, a set of ecologically relevant toxicological information in a site-specific approach. Poecilia reticulata and Gambusia holbrooki were chosen as test species. Post-exposure feeding inhibition and the biomarkers acetylcholinesterase, lactate dehydrogenase and glutathione S-transferases were the endpoints tested. The battery of biomarkers as a whole was sensitive to the in situ exposure in an acid mine drainage impacted effluent, although responses varied between test species. Post-exposure feeding inhibition was the most sensitive endpoint, and its association with biomarker responses was discussed. The linkage between individual responses, such as feeding, and biomarkers suggested that, at least in this case, biomarkers can be relevant at higher levels of biological organization. Altogether, the proposed short-term in situ bioassay seems to be a promising tool, since it represents a reasonable compromise between sensitivity, time/cost-effectiveness and ecological relevance.  相似文献   

3.
Recently, prosobranch snails have been recommended as promising candidates for test organisms for the assessment of endocrine active chemicals. Three prosobranch snail species, the freshwater mudsnail Potamopyrgus antipodarum, the freshwater ramshorn snail Marisa cornuarietis, and the marine netted whelk Nassarius reticulatus are portrayed and their respective biotests are presented together with results of laboratory experiments and biological effect monitoring surveys in the field. All characterized species are highly sensitive toward xeno-androgens [triphenyltin (TPT), tributyltin (TBT), methyltestosterone (MT) and fenarimol (FEN)], and xeno-estrogens [bisphenol A (BPA), octylphenol (OP), ethinylestradiol], and show effects at environmentally relevant, rather low concentrations in laboratory experiments. For exposure to the xeno-androgen TPT, EC10 values range between 15.9 and 29.0 ng as Sn/L (sediment 0.03 μg as Sn/kg), for TBT, EC10 values are found between 3.42 and 37.8 ng as Sn/L (sediment 2.98 μg as Sn/kg) and effect concentrations for FEN are calculated as 18.6 ng/L (EC10) and 0.19 μg/kg (EC50 sediment; EC10 not calculable). Exposure to xeno-estrogens yielded EC10 values of 13.9 ng/L (0.19 μg/kg) for BPA, a NOEC of <1 μg/L (EC10 of 0.004 μg/kg) for OP and a NOEC of 1 ng/l (EC10 sediment of 2.2 μg/kg) for ethinylestradiol. Responses to androgens comprised the development of imposex and the reduction of fertility or embryo production, effects of estrogens included the stimulation of egg production and embryo production, and the increased weight of glands. Also, biological effect monitoring studies with P. antipodarum and N. reticulatus in several rivers or estuarine areas revealed the capacity of the biotests to detect an androgenic or estrogenic potential of sediment samples. A comparison of the three test species with regard to sensitivity and practical aspects in routine application favors the freshwater mudsnail P. antipodarum for a standardized procedure, and this reproduction test will be introduced into the OECD guideline program for standardization in the near future.  相似文献   

4.
Some species of marine sponge have been shown to produce metabolites with endocrine-altering and cell growth regulatory properties. Since cell division and differentiation are controlled, in part, by the mitogen-activated protein kinase-extracellular signal-regulated kinase (MAPK/ERK) cascade, we tested extracts (1.0 mg/ml) from six shallow water marine species obtained in the Florida Keys for effects on MAPK/ERKl,2 (sub-variant of EC 2.7.1.37) activity in incubations with SW-13 human adrenal carcinoma cells in culture. In these short-term incubations, extracts from two species, the purple bleeding sponge (Iotrochota birotulata) and the West Indian bath sponge (Spongia barbara), significantly inhibited MAPK/ERK1,2 activity (to 51 and 44% of control levels, respectively) without altering cell survival. Western blots for phosphorylated and total ERK showed that ERK2 predominated over ERK1 by a factor of about 4:1 and that the phosphorylated forms of these isozymes were strongly suppressed by active extracts from both sponges. Another species, the green sponge (Haliclona veridis), whose extract has been shown previously to activate guanylate cyclase and to inhibit adenylate cyclase in a variety of mammalian tissues, was found not to affect MAPK/ERK1,2 in human adrenal carcinoma cultures but did lyse and kill most of these cultured cells. Extracts from the sheepswool sponge (Hippospongia lachne) and the bleeding sponge (Oligoceras hemorrhages) did not significantly affect either MAPK/ERK1,2 activity or the survival of attached cells. An extract from the fire sponge (Tedania ignis) did not alter MAPK/ERK1,2 activity but did modestly decrease cell viability. These studies document for the first time species-specifc effects of marine sponge extracts on the MAPK/ERK1,2 cascade and on the growth and survival of human adrenal carcinoma cells in culture.  相似文献   

5.
The objective of this study was to evaluate if the Lemna -bioassay is appropriate to test contaminated sediments. A mixture of sand was spiked with phenanthrene to investigate whether sediment-bound pollutants can affect the plants via direct contact of the roots or the underside of the leaves. After 24 h of equilibration for sorption/desorption processes, the test was carried out in the sediment–water mixture, and another test was performed with the aqueous phase which was separated from the sediment. The growth inhibition of Lemna was nearly the same in both tests. Hence it follows that the toxicant is adsorbed from the aqueous phase via the underside of the leaves and sediment bound phenanthrene is not bioavailable. Polycyclic aromatic hydrocarbons are known to show photoinduced toxicity to plants in the presence of UV which is a result of photosensitization reactions in the plant and photomodification to more toxic and better soluble photoproducts. Photoinduced toxicity could be observed in the water phase during UVB treatment, whereas the presence of suspended sediment probably lowered the UV intensity, resulting in a lower growth inhibition.  相似文献   

6.
Seventeen Great Lakes sediments ranging in degree of expected toxicity were evaluated using a 21 day sediment elutriate bioassay with Daphnia magna. Sediments differed in their effects on survival, age at first reproduction, the number of broods produced and the total number of young produced per adult. Sediments producing low survivorship (50–60%) also had negative effects on reproduction. However, both positive and negative effects on reproduction were found among sediments producing high survivorship. To integrate all test end-points, a stochastic matrix population model was constructed and parameterized with survival and reproduction data from each sediment. By including estimates of variability in vital rates, the model output provided quantitative estimates of uncertainty in projected population size. Sediment effects on survival and reproduction translated into large differences in projected population growth; mean estimates of projected population size at day 28 of the simulations ranged over two orders of magnitude among the 17 sediments. Reproductive timing (e.g. age at first reproduction), followed by fecundity and survivorship, had the largest effect on population growth. Results of this study also indicate that the presence of suspended sediment in elutriates may confound toxicity evaluations using cladocerans. The concentration of total suspended solids was negatively correlated with age at first reproduction and positively correlated with measures of fecundity and population growth. In order to realize the potential benefits of chronic testing we must develop ecologically relevant ways of interpreting sediment bioassay results and expressing the uncertainty associated with our estimates of ecological risk.  相似文献   

7.
Burkholderia cepacia DA2, isolated from marine sediment of the South China Sea, is capable of utilizing dimethyl phthalate (DMP) as the sole source of carbon and energy. During the transformation of DMP in batch culture, its corresponding degradation intermediates were identified as monomethyl phthalate (MMP) and phthalate acid (PA) sequentially over the time of incubation. The biodegradation biochemical pathway of DMP was DMP to MMP and then to PA before mineralization. Degradation of DMP by B. cepacia DA2 was also dependent upon DMP-induction, and the initial concentrations of DMP affected the degradation rate. Degradation kinetics fit well with the modified Gompertz model. The optimum pH and salinity was 6.0 and <5‰, respectively, for DMP degradation by B. cepacia DA2. This study showed that the indigenous microorganisms of the deep-ocean sediments are capable of DMP degradation completely.  相似文献   

8.
A miniaturized and low-cost algal growth-inhibition assay, with Pseudokirchneriella subcapitata, based on the standard ISO 8692 and using 96-well microplates, was tested and optimized in this work, to be used as a useful tool for pollutant phytotoxicity screening. For validation, the performance of the microplate algal growth-inhibition assay was first compared with the standard flask assay for the toxicity testing of five reference toxicants (copper(II) sulfate, zinc sulfate, potassium permanganate, potassium dichromate and 3,5-Dichlorophenol) and six wastewater samples. Statistical evaluation of EC50 results from both methods demonstrated a good agreement between microplate and flask assays either in testing chemicals (r 2 = 0.975, p < 0.0017) or environmental samples toxicity (r 2 = 0.984, p < 0.0001). In addition, the performance of this algal microplate bioassay was also evaluated in comparison with Lemna test, ISO 20079, for phytotoxicity assessment of 27 wastewater samples from industries and treatment plants. The results showed that the algal test was more sensitive for most of the samples, but a significant agreement between both tests was observed (r 2 = 0.644, p < 0.0001). In conclusion, this miniaturized test can be a good tool to include in a battery of tests for phytotoxicity screening of a wide range of chemicals and environmental samples, with the advantage of requiring low sample volumes for the test, allowing large numbers of samples to be tested, and generating low volumes of waste.  相似文献   

9.
海绵是目前海洋天然产物研究中最吸引人的海洋生物之一,海绵中含有丰富的、结构新颖的次生代谢产物,大多数具有显著的生理活性。Phakellia属海绵属于寻常海绵纲软海绵目小轴海绵科,种类较多,分布广泛,在国内外得到了广泛的研究。对近几十年来从Phakellia属海绵中分离鉴定的次生代谢产物进行了系统的归纳整理,这些化学成分主要包括环肽、生物碱、聚醚、萜类、甾醇、炔酸等种类,并对其药理活性进行了简单总结,对Phakellia属海绵的进一步研究开发具有一定的借鉴和指导意义。  相似文献   

10.
The agglutinin from the red marine alga Hypnea cervicornis (HCA) was tested in models of nociception and inflammation. The role of carbohydrate-binding sites and the systemic toxicity were assessed. HCA (10−1, 1, and 10 mg/kg) administered i.v. to mice inhibited writhes induced by acetic acid and, at 10 mg/kg, inhibited the second phase of the formalin test, but did not alter the response latency in the hot-plate test. HCA (1 mg/kg) administered i.v. to rats reduced carrageenan-induced paw edema at 1, 2, and 3 h after challenge, but not edema induced by dextran. The neutrophil migration induced by both N-formyl-methionyl-leucyl-phenylalanine (fMLP) and carrageenan was inhibited by HCA at 10−1, 1, and 10 mg/kg. The combination of HCA (1 mg/kg) and its ligand mucin reversed the lectin inhibitory effect on carrageenan-induced neutrophil migration and acetic acid-induced writhes. The i.v. treatment of rats with HCA (1 mg/kg) for 7 days did not affect body mass; liver, kidney or heart wet weight; blood leukocyte counts; urea, creatinine or serum transaminase activity; or macroscopy of the organs examined. In short, H. cervicornis agglutinin showed important antinociceptive and anti-inflamatory activity via interaction with the lectin carbohydrate-binding site.  相似文献   

11.
The impact of ballast water discharge from an oil refinery in Whitegate Harbour, Co. Cork, Ireland to the Manila clam, Tapes semidecussatus, was investigated using a whole sediment bioassay. Bioassay organisms were exposed to surface sediments for a period of 21 days, including a reference and control sediment, collected from the vicinity of a ballast water discharge pipe. At the whole organism level, mortality and burrowing behaviour (assessed as time taken for organisms to burrow into the sediment) were used to determine the effects of exposure to test sediments. After 21 days, clam mortality was higher in surface sediments collected directly at the point of the ballast water discharge pipe than from all other test sediments assayed. After 10 days exposure to test sediments collected from the vicinity of the ballast water discharge pipe, the burrowing behaviour of animals was significantly different to the behaviour of animals exposed to uncontaminated sediments.  相似文献   

12.
Four bioassays [MicrotoxTM, MutatoxTM, sister chromatid exchange (SCE), and metabolic cooperation] were used to analyze marine sediment extracts fractionated by two different methods: silica gel column chromatography and acid–base fractionation. Results indicated that a sediment extract fractionated with different methods can lead to different conclusions about the same sediment. This research also further evaluated the new, mutagenic, bacterial bioassay Mutatox. Mutatox generally correlated with SCE and the Salmonella typhimurium assays. This rapid, operationally simple bioassay has potential as a screening bioassay to detect genotoxic agents. © 1994 by John Wiley & Sons, Inc..  相似文献   

13.
Rooted aquatic plants are being used increasingly to test the toxicity of sediments. However, effects of naturally occurring substrate constituents on most potential test species are not well understood even though their effects could affect the test results. The objective of this study was to determine the effect of substrate salinity (NaCl) on early seedling survival and growth of the emergent macrophytes, Scirpus robustus Pursh and Spartina alterniflora Loisel. Results of four 21- and 28-day toxicity tests, conducted in an artificial sediment, indicated interspecific differences in NaCl sensitivity when based on changes in shoot, root and whole plant dry-weight biomass. Concentrations of 7.8 g NaCl/ and 19.2 g NaCl/ first reduced early seedling biomass of S. robustus and S. alterniflora (P < 0.05), respectively, when compared to plants grown in sediment containing no measurable salinity. Seedling survival was not affected at average concentrations of 17.5 g NaCl/ or less for S. robustus and 22.3 g NaCl/ or less for S. alterniflora. The results indicate that substrate salinity is an important consideration in the selection of test species for laboratory phytotoxicity tests conducted with estuarine sediments, particularly if determination of chronic toxicity attributable to anthropogenic contamination is the primary objective.  相似文献   

14.
《Pharmaceutical biology》2013,51(12):1826-1830
Abstract

Context: Marine natural products are a rich source of potent, selective, and structurally novel compounds. Marine bacteria are considered the most promising source of biologically active compounds which can be applied to treat a wide range of diseases.

Objective: The current study was designed to establish the bases for a future marine exploration in the Ecuadorian coast based on the molecular identification of a marine bacterium and its potential use as an antibacterial or cytotoxic compounds source.

Materials and methods: Isolation and characterization of the marine bacterium were carried out through microbiological methods from desiccated sediment. Molecular identification was made by means of 16S rDNA analysis. MIC was measured by the microdilution broth method against six pathogenic bacteria: two Gram positive and four Gram negative strains. Cytotoxicity was evaluated by Crystal violet assay against breast adenocarcinoma (MCF7) and ductal carcinoma (T47D and ZR-75-30).

Results: Our present study has shown that EtOAc extract and fraction A1 obtained from marine Streptomyces sp. revealed the maximal antibacterial and cytotoxic activity. Enterococcus faecalis was found to be more sensitive strain (MIC 0.78?μg/ml) than the other five bacteria tested. ZR-75-30 and T47D cell lines were found to be more sensitive (IC50 value, 31.88?±?0.05 and 68.35?±?0.12?μg/ml) than adenocarcinoma MCF7 (IC50 value was 83.65?±?0.06?μg/ml).

Discussion and conclusion: The results obtained herein indicate that EtOAc extract of Streptomyces sp. has shown a strong antibacterial activity as well as moderate cytotoxic activity which make it a good candidate for metabolite isolation.  相似文献   

15.
目的 研究桦褐孔菌Inonotus obliquus水提物的毒理学性质,探究其是否具有相关生理和生殖毒性。方法 急性毒性试验,ICR小鼠,一次ig给予桦褐孔菌水提物1.00、2.00、3.00、4.00、5.00 g/kg,连续观察14 d。30 d喂养试验,Wistar大鼠,每次ig给予桦褐孔菌水提物1.50、2.00、2.50 g/kg,连续给药30 d。小鼠精子畸形试验,ICR雄性小鼠,每次ig给予桦褐孔菌水提物1.00、2.50、5.00 g/kg,连续给药5 d,给药后第35天颈椎脱臼法处死实验小鼠,取双侧附睾制片,染色,统计精子畸形率。结果 急性毒性试验,实验组小鼠给药30 min后,静伏少动,背毛竖立,出现腹泻症状,无动物死亡,实验动物24 h后恢复正常。30 d喂养试验,受试动物体质量和食物利用率与对照组相比差异不显著。脏器系数、血常规和血液生化相关指标也在正常范围内波动。病理学检查未发现组织器官的明显病变。小鼠精子畸形试验,所有实验组的精子畸形率均显著低于环磷酰胺处理的阳性对照组,桦褐孔菌水提物5.00 g/kg组小鼠精子畸形率较对照组有上升趋势。结论 桦褐孔菌水提物未表现出明显的生理毒性,但在高剂量时可能具有一定的生殖毒性。  相似文献   

16.
An integrated multilevel phytoassessment of an acid mine drainage (AMD, pH range 3.3–6.8) in southern Portugal was performed. A 7-day phytotoxicity bioassay with the duckweed Lemna gibba (chlorosis, necrosis, growth) was carried out, both in the laboratory and in situ, combined with an analysis of the resident epilithic diatom community. The toxicity test was performed with water from the AMD gradient, an unpolluted river control and acidified control water, in order to discriminate potential pH-effects from combined pH- and metal-effects. Diatom communities discriminated well among the sites (alkalophilic species versus halobiontic, acidobiontic and acidophilic species), showing inter-site differences to be larger than intra-site seasonal variations. In L. gibba exposed to AMD, necrosis and growth inhibition were higher in situ compared to the laboratory experiments. L. gibba was more sensitive to AMD than to acidified water. Already after 4 days, growth rate inhibition in L. gibba proved to be a reliable indicator of AMD-stress. Ecotoxicological thresholds obtained with L. gibba corresponded with those obtained previously with animals of intermediate tolerance to AMD. The results were summarised in a multimetric index.  相似文献   

17.

Bioassays are extensively used in ecotoxicology and there is a constant need for even more sensitive, reliable and easy to rear and obtain model organisms. Larvae of the crustacean Amphibalanus amphitrite are a good ecotoxicological model, for their high sensitivity to a wide range of toxicants and emerging contaminants. A standardized protocol for this toxicity bioassay has been recently proposed. Nevertheless, a limit of this model organism is the lack of resting stages and the need to use larvae immediately after their release from adults, thus increasing laboratory efforts related to the maintenance of adults. The aim of this work is to verify if short-term cold storage of A. amphitrite larvae prior to use in ecotoxicological tests may affect the ecotoxicological responses of these organisms. Three end-points (mortality, immobilization and swimming speed alteration) were measured on nauplii after storing them at 4?±?1?°C for different times (24, 72 and 120?h) before bioassay set-up. Bioassays were set up using: (i) clean filtered natural sea water (0.22?µm FNSW), (ii) a reference toxicant (Cadmium Nitrate) and (iii) an environmental matrix (sediment elutriate). Results show that mortality, differently from the other two endpoints, was not affected by cold-storage. Even after 5 days of larvae storage at 4?±?1?°C before bioassay set up, mortality data were comparable to those obtained for non-cold-stored organisms. Moreover, larval sensitivity to the reference toxicant and sediment elutriate did not change. Regarding the other two end points, low cadmium concentrations significantly changed immobility and swimming activity in cold-stored nauplii compared to larvae used immediately after larval release. In conclusion, short-term cold storage of A. amphitrite nauplii before bioassay set up is an appropriate procedure in ecotoxicological testing if mortality is the endpoint to be considered for final evaluation.

  相似文献   

18.
The Arabian Gulf offers a suitable location for investigating the potential impact of toxic chemicals on marine life, because it is a semienclosed, relatively shallow, small body of water. This study was carried out to evaluate the relative sensitivity, precision, and accuracy of three published microbial bioassay procedures to ascertain their ability to detect toxicity in the marine environment of Kuwait. The bioassay procedures used were dissolved oxygen depletion (DOD), viable plate count (VPC), and optical density (OD). Mixed marine bacteria isolated from the local seawater of Kuwait was used, and test samples (pollutants) investigated include mercuric chloride (HgCl2), lindane, and a wastewater samples. The DOD technique was evaluated as best for sensitivity of testing toxicity. In both brief and extended exposures, activity quotient values given by this technique were much lower than the LC50 and IC50 values given by the VPC and OD techniques. However, both VPC and OD techniques showed better reproducibility than the DOD technique, as indicated by lower coefficient of variation (CV) values. When evaluating complexity, the OD assay would be considered the least complex, then the DOD, and last would be the VPC. Although both VPC and OD assays showed better reproducibility than the DOD technique, as indicated by lower CV values, the DOD demonstrated a higher sensitivity in detecting toxicity, and showed several other advantages such as rapidity and lower expenditure of routine assay requirements. However, the initiation of short-term bioassay in Kuwait for predicting effect of pollutants in the marine environment is of necessity and importance.  相似文献   

19.
In this paper, the toxicity of linear alkylbenzene sulfonate (LAS) was evaluated in the marine microalga Isochrysis galbana using data of growth inhibition toxicity tests at 96-h exposure time. Toxicity was examined in standard conditions and by means of the modification of two variables of the test media: (1) the dilution water and (2) the content of nutrients in the test medium. For this purpose, a total of 10 toxicity test were designed: five dilution waters, four natural marine waters and one synthetic seawater; each in two different nutritive conditions, saturated nutrient concentration (SC) by the addition of modified f/2 nutritive medium, and natural nutrient concentration (NC), i.e., without the addition of f/2. At threshold toxicity levels, the dilution waters used in the test and the nutrient concentrations did not affect the toxicity of LAS. At IC50 concentrations, the toxicity of LAS is influenced by both variables: under SC conditions, the toxic effect of LAS diminishes, obtaining in all the tests IC50 > 10 mg/L LAS. Under NC conditions, IC50 concentrations ranging between 3.15 and 9.26 mg/L LAS have been obtained.  相似文献   

20.
目的 研究我国南海水域丰肉结海绵相关青霉菌Penicillium sp.HLS-216的次级代谢产物的提取分离方法 、结构鉴定及其抗肿瘤、抗炎活性.方法 采用大米固体发酵培养,乙酸乙酯提取后,经硅胶柱色谱、Sephadex LH-20凝胶柱色谱、高级液相色谱等手段进行分离,并对分离得到的单体化合物应用质谱、核磁共振等技术进行结构鉴定;采用噻唑蓝(MTT)法和Griess法对分离得到的单体化合物进行抗肿瘤、抗炎活性筛选.结果 分离得到7个化合物,分别鉴定为:黑麦酮酸F(secalonic acid F,1)、黑麦酮酸D(secalonic acid D,2)、meleagrin(3)、oxaline(4)、对羟基肉桂酰胺(4-hydroxycinnamamide,5)、对羟基苯乙酸甲酯(methyl 4-hydroxyphenylacetate,6)、对羟基苯乙醛(4-hydroxyphenylacetonitrile,7).结论 化合物5和7为首次从青霉菌中分离得到;化合物1和2显示出较强的抗肿瘤活性,化合物4表现出一定的抑制小鼠腹腔巨噬细胞一氧化氮生成的作用.  相似文献   

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