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Journal of Environmental Sciences 2011年第2期23卷 322-329页

作者： Xianji Yao Yiliang He Bo Zhang Yongsheng Chen Joseph B. Hughes School of Environmental Science and Technology Shanghai Jiao Tong University Shanghai 200240 China. School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta Georgia 30332 USA College of Fisheries and Life Science Shanghai Ocean University Shanghai 201306 China

We investigated the effects of environmental factors and properties of water-stable crystal fullerene （nC60） on the uptake of nC60 by daphnia magna based on known accumulation in our laboratory. This study was performed for seven days using different environmental factors including temperature, pH, water hardness, concentration （density of particle）, and particle size. Results demonstrated that body burden of C60 increased with time in all experiments. Body burden of C60 increased with increasing concentration and particle size, and uptake of particles 〉100 nm reached their maximums more quickly than those 〈100 nm. Under high hardness in aqueous systems with lower pH and high temperature, uptake was higher than those under opposite conditions. Uptake in all batch tests reached balance within five days. Both nC60 properties and environmental factors influenced uptake of nC60 by D. magna in an aqueous system. Additionally, environmental factors may have affected accumulation by changing nC60 properties, which are critical to understand the accumulation of fullerenes in aqueous systems.

关键词： C60 fullerene daphnia magna uptake bioaccumulation

Hormetic response of cholinesterase from daphnia magna in chronic exposure to triazophos and chlorpyrifos

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Journal of Environmental Sciences 2011年第5期23卷 852-859页

作者： Shaonan Li Yajun Tan Institute of Pesticide and Environmental Toxicology College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China. E-mail: snli@*** Research Institute of Tianjin Product Quality Inspection Technology Tianjin 300384 China

In vivo activity of cholinesterase （ChE） in daphnia magna was measured at different time points during 21-day exposure to triazophos and chlorpyrifos ranging from 0.05 to 2.50 μg/L and 0.01 to 2.00 μg/L, respectively. For exposure to triazophos, ChE was induced up to 176.5% at 1.5 μg/L and day 10 when measured by acetylthiocholine （ATCh）, whereas it was induced up to 174.2% at 0.5 μg/L and day 10 when measured by butyrylthiocholine （BTCb）. For exposure to chlorpyrifos, ChE was induced up to 134.0% and 160.5% when measured by ATCh and BTCh, respectively, with both maximal inductions detected at 0.1 Ixg/L and day 8. Obvious induction in terms of ChE activity was also detected in daphnia removed from exposures 24 hr after their birth and kept in a recovery culture for 21 days. Results indicated that the enzyme displayed symptoms of hormesis, a characteristic featured by conversion from low-dose stimulation to high-dose inhibition. In spite of that, no promotion in terms of reproduction rate and body size was detected at any tested concentrations regardless of whether the daphnia were collected at end of the 21-day exposure or at end of a 21-day recovery culture. This suggested that induction of ChE caused by anticholinesterases had nothing to do with the prosperity of the daphnia population.

关键词： daphnia magna anticholinesterase ChE enzyme promotion exposure recovery culture population prosperity

Application of enriched stable isotope technique to the study of copper bioavailability in daphnia magna

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Journal of Environmental Sciences 2011年第5期23卷 831-836页

作者： Wenhong Fan Chenguang WU Chunmei Zhao Tao Yu Yuan Zhang Department of Environmental Science and Engineering School of Chemistry and Environment Beihang University Beijing 100191 China. E-mail: fanwh @ buaa. edu. cn Chinese Research Academy of Environmental Sciences Beijing 100012 China

The biokinetics of Cu in daphnia magna, including dissolved uptake, assimilation and efflux, has been determined using a gamma 67^Cu radiotracer methodology. However, this gamma emitting radioisotope is not readily available due to its very short half-life. In the present study, we employed a stable isotope tracer （65^Cu） to determine the Cu biokinetics and compared our results to those determined using 67^Cu. The dissolved uptake rate constant of 65^Cu was 3.36 L/（***）, which is higher than that of 67^Cu （1.32 L/（***））. With increasing food concentrations from 2×10^4 to 1×10^5 cells/mL, the Cu assimilation efficiency （AE） decreased from 46% to 11%, compared to a decrease from 27% to 16% when determined using 67^Cu. The effiux of Cu from daphnia magna was quantified following both dissolved and dietary uptake. The efflux of waterborne Cu was comparable to that of dietborne Cu and the effiux rate constant （0.32-0.52 day^-l） was higher than that determined by 67^Cu （0.19-0.20 day^-1）. By considering different water properties and handling procedure between the two experiments, we believe that these differences are reasonable. Overall, this study demonstrated that the enriched stable isotope tracer technique is a powerful tool to investigate metal bioavailability and maybe a good alternative to radioactive measurements.

关键词： stable isotope daphnia magna copper bioavailability

Differences in the behavior characteristics between daphnia magna and Japanese madaka in an on-line biomonitoring system

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Journal of Environmental Sciences 2010年第5期22卷 703-708页

作者： Zongming Ren Zijian Wang Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

It is important to select suitable organisms to adapt the requirement of different environment monitoring *** our previous study,the behavioral responses of daphnia magna and Japanese madaka （Oryzias latipes） were investigated and compared under flow-through conditions in an on-line biomonitoring *** results showed that both *** and Japanese madaka had similar biological clock,but the circadian rhythms of Japanese madaka was more clearly recorded than that of *** the sensitivity of *** was about two orders of magnitudes higher than that of Japanese madaka in different types of toxic chemicals （dichlorovos,deltamethrin and cadmium chloride）.However,when both animals were used in an on-line biomonitoring system,the life span of *** was less than 7 days and Japanese madaka could last for more than one month without ***,*** was proposed to be a more sensitive bioindicator and was suitable for short term monitoring the pollution events at concentration level closing to the water quality standard,while Japanese madaka was more suitable for the long-term monitoring for accidental discharges.

关键词： daphnia magna Japanese madaka on-line biomonitoring behavioral responses

Effects of Microcystis aeruginosa on life history of water flea daphnia magna

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Chinese Journal of Oceanology and Limnology 2011年第4期29卷 892-897页

作者：刘利平李慷陈桃英戴习林江敏 James S. DIANA Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources of the Shanghai Ocean University Ministry of Education Shanghai Ocean University School of Natural Resources and Environment University of Michigan Ann Arbor MI USA

Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microcystins （MCs） in Microcystis aeruginosa, and daphnia magna exposed to M. aeruginosa, were analyzed by HPLC-MS, and the effects of M. aeruginosa on D. magna were investigated. When D. magna was exposed to M. aeruginosa for more than 2 h, Microcystin-LR （MC-LR） was detected. When exposed to 1.5× 10^6, 3× 10^6, 0.75× 10^7, and 1.5× 10^7 cell/mL of M. aeruginosa for 96 h, average survival of D. magna for treatments were 23.33%, 33.33%, 13.33%, 16.67%, respectively, which were significantly lower than the average 100% survival in the control group （P 〈 0.05）. The adverse effects ofM. aeruginosa on body length, time for the first brood, brood numbers, gross fecundity, lifespan, and population growth olD. magna were density-dependent. These results suggest that the occurrence of M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity. In the most serious situations, M. aeruginosa blooms could undermine the food web by eliminating filter-feeding zooplankton, which would destroy the ecological balance of aquaculture water bodies.

关键词： Microcvstis aeruginosa daphnia magna life history toxicity

Toxicity of Nanoscale CuO and ZnO to daphnia magna

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Chemical Research in Chinese Universities 2012年第2期28卷 209-213页

作者： ZHAO Hai-zhou LU Guang-hua XIA Jun JIN Shao-ge Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes Ministry of EducationCollege of EnvironmentHohai UniversityNanjing 210098P.R.China

The potential effects of nanoscale CuO（nCuO）,nanoscale ZnO（nZnO） and their mixtures on daphnia magna were investigated,including 48-h acute toxicity and 21-d chronic toxicity tests as well as a feeding *** results of acute toxicity show that nCuO/nZnO mixture was the most toxic followed by nCuO and *** nanoparticles（NPs） inhibited both the growth and reproduction of daphnia magna during the testing *** dependence was apparent in all the cases and the intrinsic rate of natural increase was confirmed to be a very sensitive parameter to NPs *** mixture appeared to be more toxic than the corresponding individual exposures at most cases except for the feeding behavior.

关键词： daphnia magna Nanoparticle Binary mixture Toxicity

Effects of bifenthrin on daphnia magna during chronic toxicity test and the recovery test

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Journal of Environmental Sciences 2004年第5期16卷 843-846页

作者： YEWei-hong WENYue-zhong LIUWei-ping WANGZhong-qiang InstituteofEnvironmentalSciences ZhejiangUniversityHangzhou310029China InstituteofFeedScience ZhejiangUniversityHangzhou310029China

The acute and chronic toxic effects of bifenthrin on daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on daphnia magna was presented. daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).

关键词： bifenthrin daphnia magna parental generation(F 0) F 1(1st) and F 1(3rd) recovery test toxic test

Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to daphnia magna

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Water Science and Engineering 2015年第1期8卷 40-48页

作者： Guang-hua Lu Jian-chao Liu Li-sha Sun Lu-jin Yuan Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education College of Environment Hohai University

In order to study toxicological effects of perfluorononanoic acid （PFNA）, perfluorooctane sulfonate （PFOS）, and their mixtures （PFNA/ PFOS） on daphnia magna （D. magna）, a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS （alone and in combination） at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21- day life cycle. The biomarkers, including acetylcholinesterase （ACHE）, superoxide dismutase （SOD）, and catalase （CAT） activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds （PFCs） inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers, including ACHE, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.

关键词： Toxicity effect Perfluorononanoic acid Perfluorooctane sulfonate daphnia magna Reproduction Ingestion rate Biomarker

Developing antibodies from cholinesterase derived from prokaryotic expression and testing their feasibility for detecting immunogen content in daphnia magna

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第2期17卷 110-126页

作者： Hong-cui LIU Bing-qiang YUAN Shao-nan LI Institute of Pesticide and Environmental Toxicology Zhejiang University Institute of Technology Innovation Zhejiang University

To yield cholinesterase（ChE） from prokaryotic expression, the ChE gene that belongs to daphnia magna was amplified by reverse transcription-polymerase chain reaction（RT-PCR） using forward primer 5＇-CCCYGGNGCSAT GATGTG-3＇ and reverse primer 5＇-GYAAGTTRGCCCAATATCT-3＇. To express the gene, one sequence of the amplified DNA, which was able to encode a putative protein containing two conserved carboxylesterase domains, was connected to the prokaryotic expression vector PET-29a（＋）. The recombinant vector was transformed into Escherichia coil BL21（DE3）. Protein expression was induced by isopropy-D-thiogalactoside. The expressed ChE was used as an immunogen to immunize BALB/c mice. The obtained antibodies were tested for their specificity towards crude enzymes from species such as Alona milleri, Macrobrachium nipponense, Bombyx mori, Chironomus kiiensis, Apis mellifera, Eisenia foetida, Brachydanio rerio, and Xenopus laevis. Results indicated that the antibodies had specificity suitable for detecting ChE in daphnia magna. A type of indirect and non-competitive enzyme-linked immunosorbent assay（IN-ELISA） was used to test the immunoreactive content of ChE（ChE-IR） in Daphina magna. The detection limit of the IN-ELISA was found to be 14.5 ng/ml at an antiserum dilution of 1：22 000. Results from tests on daphnia magna exposed to sublethal concentrations of triazophos indicated a maximal induction of 57.2% in terms of ChE-IR on the second day after the animals were exposed to a concentration of 2.10 μg/L triazophos. Testing on animals acclimatized to a temperature of 16 °C indicated that ChE-IR was induced by 16.9% compared with the ChE-IR content detected at 21 °C, and the rate of induction was 25.6% at 10 °C. The IN-ELISA was also used to test the stability of ChE-IR in collected samples. Repeated freezing and thawing had no influence on the outcome of the test. All these results suggest that the polyclonal antibodies developed against the recombinant ChE are as efficient as th

关键词： daphnia magna Cholinesterase(ChE) Polymerase chain reaction(PCR) Recombinant protein ChE Enzyme-linked immunosorbent assay(ELISA) Triazophos

A Simple Bioassay Using Fluorescent Microbeads and daphnia magna

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Journal of Environmental Science and Engineering 2011年第12期5卷 1613-1616页

作者： M. Kamaya M. Sonamoto K. Nagashima E.N. Ginatullina Department of Environmental and Energy Chemistry Faculty of Engineering Kogakuin University Hachioji-City 192-0015 Japan

The amount of microbeads ingested by daphnia magna decreases on exposure to toxic materials; tins oenawor was used to develop a toxicity test. To determine the toxicity of seven metals, D. magna were collected and homogenized, and the fluorescence intensity of the microbeads ingested by D. magna was measured. The amount of ingestion was determined from fluorescence intensity. The fluorescence intensity was half of that of the controls which was measured as the 30 min-FI50, and these data correlated well with those from an acute immobilization method （24 h-EC50）. An advantage of the method using fluorescent beads is that an estimate of the 24 h-EC50 can be obtained.

关键词： Bioassay daphnia magna ingestion of fluorescent microbeads metal ions.