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Sample records for fish malachite green

  1. Malachite green photosensitive plates.

    PubMed

    Solano, C

    1989-08-15

    An experimental study of the behavior of malachite green sensitized plates was carried out. The transmittance variation of the irradiated plates was taken as a parameter. It has been observed that photoreduction in the malachite green plates is present only when ammonium dichromate is added to the plates. The introduction of external electron donors does not improve the photochemical reaction. It has been determined that malachite green molecules form a weak complex with the dichromate molecules and this complex can only be destroyed photochemically. This effect can explain the limited response of the malachite green dichromated plates.

  2. Final report on CCQM-K85: Malachite green in fish tissue

    NASA Astrophysics Data System (ADS)

    Biesenbruch, Sabine; Hopley, Chris; O'Connor, Gavin; Ellison, Stephen L. R.

    2013-01-01

    During a review of its activities, the organic analysis working group of the consultative committee for amount of substance noted that evidence supporting institute capabilities for providing services supporting the food sector was lacking. A request was made for a proposal of a study that would imply an institute's broader capability for the analysis of trace residues in food. Malachite green is a triphenylmethane dye with powerful antifungal properties. Its presence in food is not permitted and routine monitoring is performed in many regions at the µg/kg level. Its measurement is considered challenging for a number of reasons. Malachite green readily metabolises to leucomalachite green, with the sum of both forms being reported as 'total' malachite green. However, the two compounds have different stability and extraction requirements and often readily interconvert, proving a challenge for the successful quantification of both. The study material was a specially prepared homogenized salmon tissue from fish that had been administered with malachite green. Laboratories were requested to measure malachite green and leucomalachite green with the sum of both being reported and used for this key comparison. All laboratories used liquid chromatography-mass spectrometry with a compound-specific isotope dilution method. Six laboratories participated in the study, with all six providing results for malachite green, leucomalachite green and 'total' malachite green, reported as the sum of the two forms. A number of estimators were proposed for the calculation of the key comparison reference value (KCRV), with the working group deciding on the median and its uncertainty estimate as the most appropriate. This resulted in a KCRV of (9.77 ± 0.35) ng/g. The calculated degrees of equivalence for all laboratories were less than 1 ng/g. This was considered exceptional, especially when the complexity of the matrix, the differential partitioning of the two interconverting compounds

  3. Analytical Methods for Malachite Green : Completion Report : Malachite Green Analysis in Water.

    SciTech Connect

    Allen, John L.; Gofus, Jane E.; Meinertz, Jeffery R.

    1991-06-01

    Malachite green is a known teratogen and therefore its use is limited to nonfood fish under an Investigational New Animal Drug permit (INAD), number 2573. Although a charcoal adsorption column was developed to remove malachite green from hatchery water, INAD compliance requires that the malachite green residue concentrations in any effluent from hatcheries using the chemical be quantified. Therefore, we developed a method for the analysis of malachite green residues in water. Enrichment of the residues of malachite green in water on a diol column followed by High Performance Liquid Chromatographic (HPLC) analysis gives a minimum sensitivity of less than 10 ppb for the chemical. When combined with post-column oxidation using a lead oxide post-column reactor, the procedure can be used for the simultaneous analysis of malachite green in its leuco form, a decomposition product of the dye, as well as its chromatic form. Recovery of the leuco form is pH dependent and water samples should be adjusted to pH 6 to optimize recovery of this form. Water samples spiked with malachite green were concentrated on a diol column followed by elution with 0.05 M p-toluene sulfonic acid in methanol. The methanol elutes were analyzed by HPLC. Pond water samples spiked with malachite green and leuco malachite green yielded average recoveries of 95.4% for malachite green and 57.3% for leuco malachite green. Tap water samples spiked with the carbinol form of malachite green gave average recoveries of 98.6%. The method is very sensitive and is capable of detecting malachite green residues in water at less than 10 ppb. Fish culturists, who cannot find an effective replacement for malachite green, can utilize the method to ensure that their effluents comply with INAD regulations. 13 refs., 2 figs., 7 tabs.

  4. Mini-column assay for rapid detection of malachite green in fish.

    PubMed

    Shalaby, Ali R; Emam, Wafaa H; Anwar, Mervat M

    2017-07-01

    A simple, rapid and economical mini-column method for detecting malachite green (MG) residue in fish was developed. The method used a column with 2mm ID that was tightly packed with silica gel followed by alumina. Detection of MG was performed by viewing the developed mini-column at visible light by naked eye; where MG was seen as compact green band at the confluence of the silica gel layer with alumina layer. The limit of detection of the assay was 2ng which conform the minimum required performance limit (MRPL). Evaluation utility of the method indicated that all blank and spiked samples at levels below MRPL were assessed as accepted. The intensity of the green band increased whenever MG level in the extract increased; indicated that suggested mini-column technique could be used for semi-quantitative determination of MG in fish samples. The method can be used to select the questionable samples.

  5. Determination of malachite green in fish based on magnetic molecularly imprinted polymer extraction followed by electrochemiluminescence.

    PubMed

    Huang, Baomei; Zhou, Xibin; Chen, Jing; Wu, Guofan; Lu, Xiaoquan

    2015-09-01

    A novel procedure for selective extraction of malachite green (MG) from fish samples was set up by using magnetic molecularly imprinted polymers (MMIP) as the solid phase extraction material followed by electrochemiluminescence (ECL) determination. MMIP was prepared by using Fe3O4 magnetite as magnetic component, MG as template molecule, methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking agent. MMIP was characterized by SEM, TEM, FT-IR, VSM and XRD. Leucomalachite green (LMG) was oxidized in situ to MG by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). And then MMIP was successfully used to selectively enrich MG from fish samples. Adsorbed MG was desorbed and determined by ECL. Under the optimal conditions, calibration curve was good linear in the range of 0.29-290 μg/kg and the limit of detection (LOD) was 7.3 ng/kg (S/N=3). The recoveries of MMIP extraction were 77.1-101.2%. In addition, MMIP could be regenerated. To the best of our knowledge, MMIP coupling with ECL quenching of Ru(bpy)3(2+)/TPA for the determination of MG has not yet been developed.

  6. Quantitative and confirmatory analyses of malachite green and leucomalachite green residues in fish and shrimp.

    PubMed

    Andersen, Wendy C; Turnipseed, Sherri B; Roybal, José E

    2006-06-28

    Liquid chromatographic methods are presented for the quantitative and confirmatory determination of malachite green (MG) and leucomalachite green (LMG) for channel catfish, rainbow trout, tilapia, basa, Atlantic salmon, and tiger shrimp. Residues were extracted from tissues with ammonium acetate buffer and acetonitrile and isolated by partitioning into dichloromethane. LMG was quantitatively oxidized to the chromic MG with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Extracts were analyzed for total MG by liquid chromatography with both visible detection (LC-VIS) at 618 nm for routine screening and ion trap mass spectrometry (LC-MSn) with no discharge-atmospheric pressure chemical ionization for residue confirmation. The method was validated in each species fortified with LMG at 1, 2, 4, and 10 ng/g (ppb), and average recoveries ranged from 85.9 to 93.9%. Quantitative data were consistent for the two detection methods, with measured method detection limits of 1.0 ng/g for LC-VIS and 0.25 ng/g for LC-MSn. Incurred tissues from catfish, trout, tilapia, and salmon that had been treated with MG were also extracted and analyzed as part of this study.

  7. Rapid analysis of malachite green and leucomalachite green in fish muscles with surface-enhanced resonance Raman scattering.

    PubMed

    Zhang, Yuanyuan; Yu, Wansong; Pei, Lu; Lai, Keqiang; Rasco, Barbara A; Huang, Yiqun

    2015-02-15

    Surface-enhanced resonance Raman scattering (SERRS) coupled with gold nanospheres was applied for rapid analysis of the hazardous substances malachite green (MG) and leucomalachite green (LMG) in fish muscle tissues. The lowest concentration of MG that could be detected was 0.5ngmL(-1) with high linear correlation (R(2)=0.970-0.998) between MG concentration and intensities of characteristic Raman peaks. A simplified sample preparation method taking less than 1h for recovering MG and LMG in fish fillets was developed for SERRS analysis, and 4-8 samples could be handled in parallel. MG and LMG could be detected in extracts of tilapia fish fillets at as low as 2ngg(-1) with SERRS and a simple principle component analysis method. For six other fish species, the lowest detectable concentration of MG ranged from 1ngg(-1) to 10ngg(-1). This study provides a new sensitive approach for the detection of trace amounts of the prohibited drugs MG and LMG in muscle food, which has the potential for rapidly screening a large number of samples.

  8. Production of antibodies for selective detection of malachite green and the related triphenylmethane dyes in fish and fishpond water.

    PubMed

    Yang, Mei-Chun; Fang, Jim-Min; Kuo, Tzong-Fu; Wang, Da-Ming; Huang, Yi-Lin; Liu, Liang-Yirn; Chen, Pen-Heng; Chang, Tong-Hsuan

    2007-10-31

    This study provides a practical method for production of the antibodies against malachite green (MG) and its primary metabolite leucomalachite green (LMG). Two ELISA kits are constructed with the MG and LMG antibodies for detection of the residual MG and LMG in fish muscle and fishpond water. The detection limit is established at the level of 0.05 microg/L for both MG and LMG. Our ELISA kits show the advantages of good specificity, high sensitivity, and convenience in rapid screening of MG and LMG residues. The sample of fishpond water, without extraction or prior preparation, is directly assayed by the ELISA kit. More then 80 fish samples can be simultaneously tested in a kit. The toxic crystal violet and its metabolite leucocrystal violet of illegal use in aquaculture are detected by our prepared MG and LMG antibodies, whereas the antibodies do not cross-react with common antibiotics, sulfonamides, and benzene derivatives.

  9. Optimization of a liquid chromatographic method for determination of malachite green and its metabolites in fish tissues

    USGS Publications Warehouse

    Plakas, S.M.; ELSaid, K.R.; Stehly, G.R.; Roybal, J.E.

    1995-01-01

    A liquid chromatographic (LC) method was adapted and optimized for the determination of malachite green and its metabolites in fish plasma and muscle, Residues in plasma were extracted with acetonitrile, the extract was evaporated to dryness, and residues were resolubilized for LC analysis, Residues in muscle were extracted with an acetonitrile-acetate buffer mixture, reextracted with acetonitrile, and partitioned into methylene chloride with final cleanup on alumina and propylsulfonic acid solid-phase extraction columns, Residue levels were determined by using an LC cyano column with a PbO2 postcolumn and visible detection (618 nm). Overall mean recoveries of parent malachite green (MG-C) and its major metabolite, leucomalachite green (MG-L), from plasma were 93 and 87%, respectively, at fortification levels ranging from 25 to 250 ppb, Overall mean recoveries of MG-C and MG-L from muscle were 85 and 95%, respectively, at fortification levels ranging from 5 to 100 ppb, Relative standard deviations (RSDs) of recoveries at all fortification levels ranged from 3.9 to 7.0% for plasma and from 2.1 to 5.2% for muscle, The method was applied to incurred residues in tissues sampled from catfish after waterborne exposure to [C-14]MG-C. Mean recoveries of total radioactive residues in plasma and muscle throughout the extraction and cleanup process were 88 and 87%, respectively, and corresponding RSDs for MG-C and MG-L were in the same range as those for fortified tissues, MG-L, was confirmed as the major metabolite of MG-C in catfish.

  10. Quirks of dye nomenclature. 6. Malachite green.

    PubMed

    Cooksey, C J

    2016-08-01

    Malachite green was discovered independently by two researchers in Germany in the 19(th) century and found immediate employment as a dye and a pigment. Subsequently, other uses, such as staining biological specimens, emerged. A much later application was the control of fungal and protozoan infections in fish, for which the dye remains popular, although illegal in many countries owing to a variety of toxicity problems. In solution, malachite green can exist as five different species depending on the pH. The location of the positive charge of the colored cation on a carbon atom or a nitrogen atom is still debated. The original names of this dye, and their origins, are briefly surveyed.

  11. Quantification of malachite green in fish feed utilising liquid chromatography-tandem mass spectrometry with a monolithic column.

    PubMed

    Abro, Kamran; Mahesar, Sarfaraz Ahmed; Iqbal, Seema; Perveen, Shahnaz

    2014-01-01

    The purpose of this study was to develop a rapid and sensitive method for the quantification of malachite green (MG) in fish feed using LC-ESI-MS/MS with a monolithic column as stationary phase. Fish feed was cleaned using ultrasonic assisted liquid-liquid extraction. The separation was achieved on a Chromolith® Performance RP-18e column (100 × 4.6 mm) using gradient mobile phase composition of methanol and 0.1% formic acid at the flow rate of 1.0 ml min⁻¹. The analyte was ionised using electrospray ionisation in positive mode. Mass spectral transitions were recorded in selected reaction monitoring (SRM) mode at m/z 329.78 → m/z 314.75 with a collision energy (CE) of 52% for MG. The system suitability responses were calculated for reproducibility tests of the retention time, number of theoretical plates and capacity factor. System validation was evaluated for precision, specificity and linearity of MG. The linearity and calibration graph was plotted in the range of 15.0-250 ng ml⁻¹ with the regression coefficient of >0.997. The lower limits of detection and quantification for MG were 0.55 and 1.44 ng ml⁻¹, respectively, allowing easy determination in fish feed with accuracy evaluated as a percentage recovery of 92.1% and precision determined as % CV of < 5. The method was also extended to the determination of MG in an actual fish feed. The sensitivity and selectivity of LC-ESI-MS/MS using monolithic column offers a valuable alternative to the methodologies currently employed for the quantification of MG in fish feeds.

  12. Validation of an LC-MS/MS method for malachite green (MG), leucomalachite green (LMG), crystal violet (CV) and leucocrystal violet (LCV) residues in fish and shrimp.

    PubMed

    Ascari, Jociani; Dracz, Sérgio; Santos, Flávio A; Lima, J A; Diniz, Maria Helena G; Vargas, Eugênia A

    2012-01-01

    A quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous analyses of malachite green (MG), crystal violet (CV) and its major metabolites, leucomalachite green (LMG) and leucocrystal violet (LCV) residues in fish and shrimp samples has been validated. Fish and shrimp samples were extracted with citrate buffer/acetonitrile, and the extracts were purified on strong cation-exchange (SCX) solid-phase extraction (SPE) cartridge. After conversion of LMG into MG using a post column oxidation reactor containing lead (IV) oxide (PbO(2)), the effluents were analysed. Residues were analysed using positive-ion electrospray ionisation (ESI). Identification and quantification of analytes were based on the ion transitions monitored by multiple reaction monitoring (MRM). Validation of the method was carried out in accordance with the Decision 2002/657/EC, which establishes criteria and procedures for the validation of methods. The following parameters were determined: decision limit (CCα), detection capability (CCβ), linearity, accuracy, precision, selectivity, specificity and matrix effect. The decision limits (CCα) for MG, LMG, CV and LCV were 0.164, 0.161, 0.248 and 0.860 µg kg(-1). The respective detection capabilities (CCβ) were 0.222, 0.218, 0.355 and 1.162 µg kg(-1). Typical recoveries (intermediate precision) in shrimp, for MG, CV, LMG and LCV for 2.0 µg kg(-1) level fortified samples using the optimised procedure were in the range 69%, 97%, 80.3% and 71.8%, respectively. The findings demonstrate the suitability of the method to detect simultaneously MG, CV and its metabolite (LMG and LCV) in fish and shrimp.

  13. Effects of malachite green on the mRNA expression of detoxification-related genes in Nile tilapia (Oreochromis niloticus) and other major Chinese freshwater fishes.

    PubMed

    Li, Guangyu; Shen, Dan; Liang, Xu-Fang; He, Yan; He, Shan

    2013-03-01

    The use of malachite green (MG) in fish farming is prohibited in China due to its potentially toxicological and carcinogenic nature, but it is still illegally used in some places. The aim of this study was to investigate the time and concentration-dependent responses of xenobiotic metabolizing and detoxification-related genes in diverse fishes exposed to MG both in vivo and in vitro. Experimental fish were administered to two exposure groups of malachite green (MG) (0.10 and 0.50 mg L⁻¹) for 8 h. The hepatocytes isolated from Nile tilapia were incubated with MG (0.5, 1.0, and 2.0 mg L⁻¹) for 8 and 24 h, respectively. In vivo, exposure to 0.10 and 0.50 mg L⁻¹ MG for 8 h caused significant changes of the detoxification-related genes on the mRNA expression levels. Low-concentration (0.10 mg L⁻¹) level of MG induced significant increase on the mRNA expression level of GSTR gene in Nile tilapia and other fishes. The mRNA expression of grass carp UCP2 was significantly induced when exposed to 0.5 mg L⁻¹ MG. However, the mRNA expression levels of GSTA, CYP1A, and GPX were inhibited significantly by 0.5 mg L⁻¹ MG in Nile tilapia, grass carp, and Taiwan snakehead. In vitro, the significant increase of mRNA expression of these genes was detected after exposure to 0.5 mg L⁻¹ MG (UCP2), and 1.0 mg L⁻¹ MG (CYP1A1, GSTA, GSTR, and UCP2). The induction of hepatic CYP1A1, GSTA, GSTR, and UCP2 in response to MG suggested a potential role of fish CYP1A1, GSTA, GSTR, and UCP2 in MG metabolism.

  14. Carcinogenicity of malachite green chloride and leucomalachite green in B6C3F1 mice and F344 rats.

    PubMed

    Culp, Sandra J; Mellick, Paul W; Trotter, Ronald W; Greenlees, Kevin J; Kodell, Ralph L; Beland, Frederick A

    2006-08-01

    Malachite green is a triphenylmethane dye used in the fish industry as an anti-fungal agent. Leucomalachite green is formed by the metabolic reduction of malachite green and persists in the tissues of exposed fish. In this study, we examined the carcinogenicity of malachite green chloride and leucomalachite green. Female F344 rats (48 per group) were fed diets containing 0, 100, 300, or 600 ppm malachite green chloride for 104 weeks, at which time the extent of tumorigenesis was assessed. Additional groups of 48 female and 48 male F344 rats were fed diets containing 0, 91, 272, or 543 ppm leucomalachite green for 104 weeks. Groups of 48 female B6C3F1 mice were fed diets containing 0, 100, 225, or 450 ppm malachite green chloride or 0, 91, 204, or 408 ppm leucomalachite green for 104 weeks. For each of the exposures, food consumption in the treatment groups was similar to the controls. Rats fed malachite green chloride or leucomalachite green had dose-dependent reductions in body weight; in mice, there were no consistent effects upon body weights with either compound. Female rats exposed to malachite green chloride had increased incidences of thyroid gland follicular cell adenoma or carcinoma and hepatocellular adenoma, and a dose-related increasing trend in mammary gland carcinoma. Female rats fed malachite green chloride and female and male rats fed leucomalachite green had a dose-related decreasing trend in the incidence of mononuclear cell leukemia. In male rats fed leucomalachite green there was a decreasing trend in pituitary gland adenoma and an increasing trend in interstitial cell adenoma of the testis. There were no treatment-related neoplasms in female B6C3F1 mice fed malachite green chloride. Female mice fed leucomalachite green had a dose-related increasing trend in the incidence of hepatocellular adenoma or carcinoma, with the incidence being significant in the highest dose group.

  15. Incorporation of flow injection analysis with dual-wavelength overlapping resonance Rayleigh scattering for rapid determination of malachite green and its metabolite in fish.

    PubMed

    Zhu, Jinghui; Qin, Mingyou; Liu, Shaopu; Liu, Zhongfang; Yang, Jidong; Hu, Xiaoli

    2014-09-15

    A flow injection analysis (FIA) system combined with dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) has been established and validated for rapid determination of malachite green (MG) and its metabolite in fish samples. Under experimental condition, MG would react with Erythrosin (Ery) to form ion-association complexes, resulting in the occurrence of two RRS peaks and a dramatic enhancement of RRS intensity. The maximum RRS peaks were located at 286 nm and 337 nm. It is noted that the increments of both of these two peaks were proportional to the concentration of MG. The detection limit of DWO-RRS was 1.5 ng/mL, which was comparable to several reported methods. Moreover, the results of real sample analysis exhibited an acceptable recovery between 97.5% and 103.6%, indicating that the method had good reproducibility.

  16. Incorporation of flow injection analysis with dual-wavelength overlapping resonance Rayleigh scattering for rapid determination of malachite green and its metabolite in fish

    NASA Astrophysics Data System (ADS)

    Zhu, Jinghui; Qin, Mingyou; Liu, Shaopu; Liu, Zhongfang; Yang, Jidong; Hu, Xiaoli

    2014-09-01

    A flow injection analysis (FIA) system combined with dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) has been established and validated for rapid determination of malachite green (MG) and its metabolite in fish samples. Under experimental condition, MG would react with Erythrosin (Ery) to form ion-association complexes, resulting in the occurrence of two RRS peaks and a dramatic enhancement of RRS intensity. The maximum RRS peaks were located at 286 nm and 337 nm. It is noted that the increments of both of these two peaks were proportional to the concentration of MG. The detection limit of DWO-RRS was 1.5 ng/mL, which was comparable to several reported methods. Moreover, the results of real sample analysis exhibited an acceptable recovery between 97.5% and 103.6%, indicating that the method had good reproducibility.

  17. Toxicity of formalin, malachite green, and the mixture to four life stages of rainbow trout

    USGS Publications Warehouse

    Bills, Terry D.; Advised by: Hosler, Charles F.; Cumming, Kenneth B.; Nord, Richard P.; Senff, Robert E.

    1974-01-01

    Formalin, malachite green, or a mixture of them are utilized in fish culture for control of external parasites of fish and control of fungus on fish and fish eggs. Very little information is available concerning the toxicity of these compounds to fish under laboratory test conditions or the differences in sensitivity to these chemicals at various life stages. This study was designed to 1) determine the toxicity of formalin, malachite green and the mixture to four life stages of rainbow trout (Salmo gairdneri) under various laboratory test conditions, 2) determine the degradation of formalin and malachite green in water, 3) determine the effect of additive toxicity, and 4) determine the differences in sensitivity of two different lots of eggs to the chemicals. The 96-hour LC50 (lethal concentration required to produce 50% mortality) for formalin against rainbow trout in soft water ranged from 580 micrograms/liter for the eyed egg stage to 134 micrograms/liter for the fingerling stage. The 96-hour LC50 for malachite green against rainbow trout in soft water ranged from 2.00 mg/L for the eyed egg stage to 0.0224 mg/L for the fingerling stage. The additive indices for formalin and malachite green when applied in combination show strictly additive toxicity as the ranges overlap zero in all tests. Deactivation indices for formalin and malachite green show essentially no change in toxicity of the solutions to rainbow trout when aged for periods of 1, 2, and 3 weeks.

  18. Determination of malachite green and its leuco form in water

    USGS Publications Warehouse

    Allen, J.L.; Meinertz, J.R.; Gofus, J.E.

    1992-01-01

    Liquid chromatographic (lc) analysis can detect malachite green residues in water at less than 10 mu-g/l. Water samples were concentrated on disposable diol columns, eluted with 0.05m P-toluene-sulfonic acid in methanol, and determined by reversed-phase lc. When combined with a lead oxide postcolumn reactor, the lc method can simultaneously determine both leuco and chromatic forms of malachite green. Recoveries averaged 95.4% For the chromatic form and 57.3% For the leuco form of malachite green oxalate and leuco malachite green in spiked pond water samples. Recoveries of the carbinol form of malachite green (an equilibrium product of the dye in water) from spiked tap water samples averaged 98.6%. Recoveries of leuco malachite green were low and ph-dependent.

  19. Determination of malachite green, crystal violet and their leuco-metabolites in fish by HPLC-VIS detection after immunoaffinity column clean-up.

    PubMed

    Xie, Jie; Peng, Tao; Chen, Dong-Dong; Zhang, Qing-Jie; Wang, Guo-Min; Wang, Xiong; Guo, Qi; Jiang, Fan; Chen, Dan; Deng, Jian

    2013-01-15

    A high performance liquid chromatography method with visible detection (HPLC-VIS) for the determination of malachite green (MG), crystal violet (CV), leucomalachite green (LMG), and leucocrystal violet (LCV) in fish has been developed after clean-up through an immunoaffinity column (IAC). Residues were simultaneously extracted from fish muscle with acetonitrile and ammonium acetate buffer. The leuco-forms, LMG and LCV, were oxidized quantitatively to the chromic CV and MG by reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Extracts were then purified on an IAC which prepared by immobilizing the anti-MG-CV antibodies by the sol-gel method. Finally, the eluents were analyzed by HPLC-VIS. The limits of detection were 0.15, 0.1, 0.18 and 0.14ng/g for MG, CV, LMG and LCV, respectively. The average recoveries in samples fortified with MG, CV, LMG and LCV over the range 0.5-10ng/g were from 71.6% to 96.8% with RSDs of 5.1-12.3% (n=6). This novel method was confirmed by liquid chromatography-tandem mass spectrometry with electrospray interface in positive mode using multiple reaction monitoring.

  20. Malachite green interferes with postantibiotic recovery of mycobacteria.

    PubMed

    Gelman, Ekaterina; McKinney, John D; Dhar, Neeraj

    2012-07-01

    The genus Mycobacterium comprises slow-growing species with generation times ranging from hours to weeks. The protracted incubation time before colonies appear on solid culture medium can result in overgrowth by faster-growing microorganisms. To prevent contamination, the solid media used in laboratories and clinics for cultivation of mycobacteria contain the arylmethane compound malachite green, which has broad-spectrum antimicrobial activity. Malachite green has no impact on the plating efficiency of mycobacteria when cells are grown under normal conditions. However, we found that malachite green interfered with colony formation when bacteria were preexposed to antibiotics targeting cell wall biogenesis (isoniazid, ethionamide, ethambutol). This inhibitory effect of malachite green was not observed when bacteria were preexposed to antibiotics targeting cellular processes other than cell wall biogenesis (rifampin, moxifloxacin, streptomycin). Sputum specimens from tuberculosis patients are routinely evaluated on solid culture medium containing high concentrations of malachite green. This practice could lead to underestimation of bacterial loads and overestimation of chemotherapeutic efficacy.

  1. Biotransformation of malachite green by Saccharomyces cerevisiae MTCC 463.

    PubMed

    Jadhav, J P; Govindwar, S P

    2006-03-01

    In recent years, use of microbial biomass for decolourization of textile industry wastewater is becoming a promising alternative in which some bacteria and fungi are used to replace present treatment processes. Saccharomyces cerevisiae MTCC 463 decolourized the triphenylmethane dyes (malachite green, cotton blue, methyl violet and crystal violet) by biosorption, showing different decolourization patterns. However, malachite green decolourized by biosorption at the initial stage and further biodegradation occurred, about 85% in plain distilled water within 7 h, and about 95.5% in 5% glucose medium within 4 h, under aerobic conditions and at room temperature. Decolourization of malachite green depends on various conditions, such as concentration of dye, concentration of cells, composition of medium and agitation. HPLC, UV-VIS, FTIR and TLC analysis of samples extracted with ethyl acetate from decolourized culture flasks confirmed the biodegradation of malachite green into several metabolites. A study of the enzymes responsible for the biodegradation of malachite green in the control and cells obtained after decolourization showed the activities of laccase, lignin peroxidase, NADH-DCIP reductase, malachite green reductase and aminopyrine N-demethylase in control cells. A significant increase in the activities of NADH-DCIP reductase and MG reductase was observed in the cells obtained after decolourization, indicating a major involvement of reductases in malachite green degradation.

  2. Biotransformation of Malachite Green by the Fungus Cunninghamella elegans

    PubMed Central

    Cha, Chang-Jun; Doerge, Daniel R.; Cerniglia, Carl E.

    2001-01-01

    The filamentous fungus Cunninghamella elegans ATCC 36112 metabolized the triphenylmethane dye malachite green with a first-order rate constant of 0.029 μmol h−1 (mg of cells)−1. Malachite green was enzymatically reduced to leucomalachite green and also converted to N-demethylated and N-oxidized metabolites, including primary and secondary arylamines. Inhibition studies suggested that the cytochrome P450 system mediated both the reduction and the N-demethylation reactions. PMID:11526047

  3. Uptake, tissue distribution, and metabolism of malachite green in the channel catfish (Ictalurus punctatus)

    USGS Publications Warehouse

    Plakas, S.M.; El Said, K. R.; Stehly, G.R.; Gingerich, W.H.; Allen, J.L.

    1996-01-01

    The disposition of malachite green was determined in channel catfish (Ictalurus punctatus) after intravascular dosing (0.8 mg . Kg-1) or waterborne exposure (0.8 mg . L-1 for 1 h). After intravascular dosing, mean plasma concentrations of the parent compound exhibited a triphasic decline with a terminal elimination half-life of 6.2 h. Malachite green was rapidly absorbed and concentrated in the tissues during waterborne exposure. The rate of accumulation was directly related to pH of the exposure water. After waterborne exposure, elimination of the parent compound from plasma also was triphasic with a terminal half-life of 4.7 h. In muscle, the half-life of the parent compound was approximately 67 h. Malachite green and its metabolites were widely distributed in all tissues. In fish exposed to C-14-labeled malachite green, total drug equivalent concentrations were highest in abdominal fat and lowest in plasma. Malachite green was rapidly and extensively metabolized to its reduced form, leucomalachite green, which was slowly eliminated from the tissues. Leucomalachite green is an appropriate target analyte for monitoring exposure of channel catfish to this drug.

  4. Determination of residues of malachite green in aquatic animals.

    PubMed

    Bergwerff, Aldert A; Scherpenisse, Peter

    2003-05-25

    Residues of malachite green (MG) were extracted from homogenized animal tissues with a mixture of McIlvaine buffer (pH 3.0)-acetonitrile, and purified over an aromatic sulfonic acid solid-phase extraction column followed by HPLC or LC-ESI-MS-MS analysis. Ascorbic acid and N,N,N',N'-tetramethyl-1,4-phenylenediamine dihydrochloride were added to reduce de-methylation of the dye. Responses were recorded at 620 nm (HPLC) or by multiple-reaction-monitoring (LC-MS-MS) after post-column oxidation using PbO(2). MG and its primary metabolite leuco-malachite green (LMG) were successfully determined at 2.5-2000 microg/kg in catfish, eel, rainbow trout, salmon, tropical prawns and turbot, with a limit of detection at 1 microg/kg (HPLC) and 0.2 microg/kg (LC-MS-MS) for both MG and LMG. Recoveries for LMG were between 86+/-15% (prawn) and 105+/-14% (eel). Freeze-thawing cycles, and storage at 4 degrees C and -20 degrees C affected the recovery of both MG and LMG. Analyses of eel, trout and (processed) salmon field samples collected at local retailers, fish-market and -shops demonstrated trace levels of MG-residues.

  5. Biodegradation of malachite green by Brevibacillus laterosporus MTCC 2298.

    PubMed

    Gomare, Sushama S; Parshetti, Ganesh K; Govindwar, Sanjay P

    2009-11-01

    Brevibacillus laterosporus MTCC 2298 was screened for the decolorization of eight triphenylmethane dyes. Decolorization of malachite green was found to be fastest (87% within 3 hours, at the concentration 0.1 g/L) among the screened dyes. Various triphenylmethane dyes showed differential induction patterns of the dye-degrading enzymes. The activities of the laccase, nicotinamide adenine dinucleotide-dichlorophenolindophenol reductase (NADH-DCIP reductase), malachite green reductase, and aminopyrine N-demethylase were increased in the cell-free extract obtained after decolorization of malachite green. Fourier transform infrared spectral analysis indicated formation of N-demethylated products, including primary and secondary aryl amines. High-performance liquid chromatography analysis confirmed the transformation of malachite green into new metabolites rather than its reduced form, leucomalachite green. Gas chromatography-mass spectroscopy analysis detected new degradation products, such as reduced tetradesmethyl leucomalachite green (m/z 283) and [4-(1-cyclohexyl)-(1'-phenyl)-methyl]-2, 4-hexenoic acid (m/z 282). Complete decolorization of malachite green also was observed by the partially purified laccase from B. laterosporus.

  6. Development of a fast ELISA for the specific detection of both leucomalachite green and malachite green

    NASA Astrophysics Data System (ADS)

    Jiang, Yousheng; Chen, Li; Hu, Kun; Yu, Wenjuan; Yang, Xianle; Lu, Liqun

    2015-04-01

    Malachite green (MG), a dye, is an antifungal agent that has been used to treat and prevent fish diseases. It is metabolized into reduced leucomalachite green forms (LMG) that may reside in fish muscles for a long period, thus being harmful to human health. The aim of this study was to develop a competitive and direct enzyme-linked immunosorbent assay (ELISA) to detect MG and LMG specifically. The monoclonal antibody (mAb) to LMG was generated using a hybridoma technique. The obtained mAb showed good cross-reactivity (CR) to malachite green (MG), but not to crystal violet (CV) and Brilliant Green (BG). The mAb was used to develop a fast detecting ELISA of MG and LMG in fish. By introducing the conjugation LMG-HRP, the detection capability was 0.37 ng mL-1 for MG and LMG. The mean recovery from spiked grass carp tissues ranged from 76.2% to 82.9% and the coefficients of variation varied between 1.8% and 7.5%. The stable and efficient monoclonal cell line obtained is a sustainable source of sensitive and specific antibody to MG and LMG.

  7. Determination of adulteration of malachite green in green pea and some prepared foodstuffs by micellar liquid chromatography.

    PubMed

    Ashok, Vipin; Agrawal, Nitasha; Durgbanshi, Abhilasha; Esteve-Romero, Josep; Bose, Devasish

    2014-01-01

    A simple, fast, and robust micellar LC method was developed for the separation and identification of the nonpermitted color malachite green in green pea and some ready-to-eat foodstuffs. Malachite green (4-[(4-dimethylaminophenyl) phenyl-methyl]-N,N-dimethylaniline) is a hazardous dye that is used to treat fungal and protozoan infections in fish and is a common adulterant (coloring agent) in green pea and other green vegetables because of its green color. In the present work, malachite green was determined in various foodstuffs using a direct injection technique on an RP C18 column with isocratic elution. The optimum mobile phase consisted of 0.15 M sodium dodecyl sulfate (SDS), 6% pentanol buffered at pH 5. Detection was carried out at 620 nm. Malachite green was eluted in 9.2 min without any interference caused by endogenous compounds. Linearities (r > 0.9999), intraday and interday precision (RSD less than 1.00%) in micellar media, and robustness were studied for method validation. LOD and LOQ were 0.10 and 0.25 ppm, respectively. The simplicity of the developed method makes it useful for routine analysis in the area of food QC.

  8. Development of a carbon filter system for removing malachite green from hatchery effluents

    SciTech Connect

    Marking, L.L. ); Leith, D. ); Davis, J. )

    1990-04-01

    The US Fish and Wildlife Service was granted an investigational New Animal Drug permit by the US Food and Drug Administration for the use of malachite green as a fungicide at selected state and federal fish hatcheries. However, the permit required that the fungicide be removed from all treated water after March 1989. A study was designed to (1) determine the type of filter and kind of carbon that was most efficient for removal of malachite green and (2) demonstrate that carbon filters can be used to remove malachite green from water used for egg incubation or to hold adult salmon before spawning. Minicolumn simulation studies showed that 8 {times} 30-mesh granular carbon was effective for continuously removing malachite green from water for 230 d at a flow rate of 500 gal/min and for only 62 d at a flow rate of 1,000 gal/min. The removal capacity at the slower flow rate was 1.1 oz of malachite green per pound of carbon. A filter system that contained 20,000 lb of activated carbon in each of two chambers was effective for removal of malachite green from treated water in adult salmon holding ponds at flows of 500 gal/min (6.4 gal/min per ft{sup 2}) and greater. The removal efficiency was 99.8% after 105 h of operation, and the adsorption capacity of the system was projected to be sufficient for 20 or more years of routine hatchery operation. A filter system that contained 2,000 lb of activated carbon in each of two chambers was effective for removal of malachite green from treated water in salmon egg incubation units at the designated flow rate of 50 gal/min (4.0 gal/min per ft{sup 2}) and also at faster flow rates. Removal efficiency decreased only slightly for faster flows in both filter systems, and the efficiency improved when treated water was passed through two filter chambers in series.

  9. Electrochemical degradation of malachite green using nanoporous carbon paste electrode

    NASA Astrophysics Data System (ADS)

    Harsini, Muji; Fitria, Faizatul; Pudjiastuti, Pratiwi

    2016-03-01

    Malachite green is a dye which is often used in the textile industry which potentially generates hazardous compound to the environment. Electrochemical degradation is a method that can decipher malachite green into harmless compounds. In this study, nanoporous carbon paste used as the anode and silver wire as the cathode. A number of the sample solution with a certain concentration containing supporting electrolyte inserted into a electrolysis cell, certain potential and current is passed through the electrode into the solution. During the degradation process, the solution stirred by a magnetic stirrer. The results showed that the optimum state of degradation at 10 volts potential with an electrolyte solution of 0.1 M NaCl, pH does not affect the results of degradation. The optimum time to degrade 50 ppm malachite green is 30 to 40 minutes to produce a harmless compound that can be indicated from the impairment COD that up to 95,05%. Results of UV-Vis spectra showed that malachite green has been degraded completely.

  10. Determination of malachite green residues in the eggs, fry, and adult muscle-tissue of rainbow-trout (Oncorhynchus-mykiss)

    USGS Publications Warehouse

    Allen, John L.; Gofus, J.E.; Meinertz, Jeffery R.

    1994-01-01

    Malachite green, an effective antifungal therapeutant used in fish culture, is a known teratogen. We developed a method to simultaneously detect both the chromatic and leuco forms of malachite green residues in the eggs, fry, and adult muscle tissue of rainbow trout (oncorhynchus mykiss). Homogenates of these tissues were fortified with [c-14] malachite green chloride and extracted with 1% (v/v) acetic acid in acetonitrile or in methanol. The extracts were partitioned with chloroform, dried, redissolved in mobile phase, and analyzed by liquid chromatography (lc) with postcolumn oxidation of leuco malachite green to the chromatic form. Lc fractions were collected every 30 s for quantitation by scintillation counting. Recoveries of total [c-14] malachite green chloride residue were 85 and 98% in eggs fortified with labeled malachite green at concentrations of 0.5 And 1.00 Mug/g, respectively; 68% in fry similarly fortified at a concentration of 0.65 Mug/g; and 66% in muscle homogenate similarly fortified at a level of 1.00 Mug/g. The method was tested under operational conditions by exposing adult rainbow trout to 1.00 Mg/l [c-14] malachite green chloride bath for 1 h. Muscle samples analyzed by sample oxidation and scintillation counting contained 1.3 And 0.5 Mug/g total malachite green chloride residues immediately after exposure and after a 5-day withdrawal period, respectively.

  11. Quantitative Detection of Trace Malachite Green in Aquiculture Water Samples by Extractive Electrospray Ionization Mass Spectrometry

    PubMed Central

    Fang, Xiaowei; Yang, Shuiping; Chingin, Konstantin; Zhu, Liang; Zhang, Xinglei; Zhou, Zhiquan; Zhao, Zhanfeng

    2016-01-01

    Exposure to malachite green (MG) may pose great health risks to humans; thus, it is of prime importance to develop fast and robust methods to quantitatively screen the presence of malachite green in water. Herein the application of extractive electrospray ionization mass spectrometry (EESI-MS) has been extended to the trace detection of MG within lake water and aquiculture water, due to the intensive use of MG as a biocide in fisheries. This method has the advantage of obviating offline liquid-liquid extraction or tedious matrix separation prior to the measurement of malachite green in native aqueous medium. The experimental results indicate that the extrapolated detection limit for MG was ~3.8 μg·L−1 (S/N = 3) in lake water samples and ~0.5 μg·L−1 in ultrapure water under optimized experimental conditions. The signal intensity of MG showed good linearity over the concentration range of 10–1000 μg·L−1. Measurement of practical water samples fortified with MG at 0.01, 0.1 and 1.0 mg·L−1 gave a good validation of the established calibration curve. The average recoveries and relative standard deviation (RSD) of malachite green in lake water and Carassius carassius fish farm effluent water were 115% (6.64% RSD), 85.4% (9.17% RSD) and 96.0% (7.44% RSD), respectively. Overall, the established EESI-MS/MS method has been demonstrated suitable for sensitive and rapid (<2 min per sample) quantitative detection of malachite green in various aqueous media, indicating its potential for online real-time monitoring of real life samples. PMID:27529262

  12. Quantitative Detection of Trace Malachite Green in Aquiculture Water Samples by Extractive Electrospray Ionization Mass Spectrometry.

    PubMed

    Fang, Xiaowei; Yang, Shuiping; Chingin, Konstantin; Zhu, Liang; Zhang, Xinglei; Zhou, Zhiquan; Zhao, Zhanfeng

    2016-08-11

    Exposure to malachite green (MG) may pose great health risks to humans; thus, it is of prime importance to develop fast and robust methods to quantitatively screen the presence of malachite green in water. Herein the application of extractive electrospray ionization mass spectrometry (EESI-MS) has been extended to the trace detection of MG within lake water and aquiculture water, due to the intensive use of MG as a biocide in fisheries. This method has the advantage of obviating offline liquid-liquid extraction or tedious matrix separation prior to the measurement of malachite green in native aqueous medium. The experimental results indicate that the extrapolated detection limit for MG was ~3.8 μg·L(-1) (S/N = 3) in lake water samples and ~0.5 μg·L(-1) in ultrapure water under optimized experimental conditions. The signal intensity of MG showed good linearity over the concentration range of 10-1000 μg·L(-1). Measurement of practical water samples fortified with MG at 0.01, 0.1 and 1.0 mg·L(-1) gave a good validation of the established calibration curve. The average recoveries and relative standard deviation (RSD) of malachite green in lake water and Carassius carassius fish farm effluent water were 115% (6.64% RSD), 85.4% (9.17% RSD) and 96.0% (7.44% RSD), respectively. Overall, the established EESI-MS/MS method has been demonstrated suitable for sensitive and rapid (<2 min per sample) quantitative detection of malachite green in various aqueous media, indicating its potential for online real-time monitoring of real life samples.

  13. [Studies on photo-electron-chemical catalytic degradation of the malachite green].

    PubMed

    Li, Ming-yu; Diao, Zeng-hui; Song, Lin; Wang, Xin-le; Zhang, Yuan-ming

    2010-07-01

    A novel two-compartment photo-electro-chemical catalytic reactor was designed. The TiO2/Ti thin film electrode thermally formed was used as photo-anode, and graphite as cathode and a saturated calomel electrode (SCE) as the reference electrode in the reactor. The anode compartment and cathode compartment were connected with the ionic exchange membrane in this reactor. Effects of initial pH, initial concentration of malachite green and connective modes between the anode compartment and cathode compartment on the decolorization efficiency of malachite green were investigated. The degradation dynamics of malachite green was studied. Based on the change of UV-visible light spectrum, the degradation process of malachite green was discussed. The experimental results showed that, during the time of 120 min, the decolouring ratio of the malachite green was 97.7% when initial concentration of malachite green is 30 mg x L(-1) and initial pH is 3.0. The catalytic degradation of malachite green was a pseudo-first order reaction. In the degradation process of malachite green the azo bond cleavage and the conjugated system of malachite green were attacked by hydroxyl radical. Simultaneity, the aromatic ring was oxidized. Finally, malachite green was degraded into other small molecular compounds.

  14. Lipoprotein processing is essential for resistance of Mycobacterium tuberculosis to malachite green.

    PubMed

    Banaei, Niaz; Kincaid, Eleanor Z; Lin, S-Y Grace; Desmond, Edward; Jacobs, William R; Ernst, Joel D

    2009-09-01

    Malachite green, a synthetic antimicrobial dye, has been used for over 50 years in mycobacterial culture medium to inhibit the growth of contaminants. The molecular basis of mycobacterial resistance to malachite green is unknown, although the presence of malachite green-reducing enzymes in the cell envelope has been suggested. The objective of this study was to investigate the role of lipoproteins in resistance of Mycobacterium tuberculosis to malachite green. The replication of an M. tuberculosis lipoprotein signal peptidase II (lspA) mutant (DeltalspA::lspAmut) on Middlebrook agar with and without 1 mg/liter malachite green was investigated. The lspA mutant was also compared with wild-type M. tuberculosis in the decolorization rate of malachite green and sensitivity to sodium dodecyl sulfate (SDS) detergent and first-line antituberculosis drugs. The lspA mutant has a 10(4)-fold reduction in CFU-forming efficiency on Middlebrook agar with malachite green. Malachite green is decolorized faster in the presence of the lspA mutant than wild-type bacteria. The lspA mutant is hypersensitive to SDS detergent and shows increased sensitivity to first-line antituberculosis drugs. In summary, lipoprotein processing by LspA is essential for resistance of M. tuberculosis to malachite green. A cell wall permeability defect is likely responsible for the hypersensitivity of lspA mutant to malachite green.

  15. Photodegradation of malachite green and malachite green carbinol under irradiation with different wavelength ranges.

    PubMed

    Fischer, A R; Werner, P; Goss, K-U

    2011-01-01

    The dye malachite green (MG) is used worldwide as a fungicide in aquaculture. It is a toxic substance which in aqueous solutions is partly converted into its non-ionic colorless form (leucocarbinol). The equilibrium between these two forms is pH-dependent (pK=6.9). To assess the photodegradation of MG under sunlight conditions, both species were irradiated separately in aqueous solutions with different pH values (4.0 and 12.0) using various ultraviolet and visible wavelength ranges (UV/VIS). A 700 W high-pressure mercury lamp with special filters was used. No artificial photooxidizers such as H₂O₂ or TiO₂ were added. MG leucocarbinol proved to be much more sensitive to irradiation than the dye form. Quantum yields Φ were calculated for some wavelength ranges as follows: MG carbinol: Φ((280-312 nm)) is 4.3 × 10⁻³, Φ((313 - 410 nm)) is 5.8 × 10⁻³, and MG dye: Φ((280 - 312 nm)) is 4.8 × 10(-5), Φ((313-365nm)) is 1.1×10⁻⁵, and Φ((> 365nm)) is 0, respectively. Therefore, the solar photolysis of MG is an important sink and primarily depends on the photodegradation of the colorless leucocarbinol. During the irradiation of MG leucocarbinol with wavelengths > 365 nm, an intermediate was formed which has photocatalytical properties.

  16. Effect of malachite green toxicity on non target soil organisms.

    PubMed

    Gopinathan, R; Kanhere, J; Banerjee, J

    2015-02-01

    Although malachite green (MG), is banned in Europe and US for its carcinogenic and teratogenic effect, the dye being cheap, is persistently used in various countries for fish farming, silk, dye, leather and textile industries. Current research, however, fails to elucidate adequate knowledge concerning the effects of MG in our ecosystem. In the present investigation, for the first time, an attempt has been made to study the effects of MG on soil biota by testing Bacillus subtilis, Azotobacter chroococcum, Saccharomyces cerevisiae, Penicillium roqueforti, Eisenia fetida and seeds of three crop plants of different families. Various tests were conducted for determining cytotoxicity, genotoxicity, acute toxicity, morphological and germination effect. Our data confirmed MG toxicity on fungi and bacteria (gram positive and gram negative organisms) showing elevated level of ROS. Genotoxicity caused in the microorganisms was detected by DNA polymorphism and fragmentation. Also, scanning electron microscopy data suggests that the inhibitory effect of MG to these beneficial microbes in the ecosystem might be due to pore formation in the cell and its eventual disruption. Filter paper and artificial soil test conducted on earthworms demonstrated a LC 50 of 2.6 mg cm(-2) and 1.45 mg kg(-1) respectively with severe morphological damage. However, seed germination of Mung bean, Wheat and Mustard was found to be unaffected in presence of MG up to 100 mL(-1) concentration. Thus, understanding MG toxicity in non target soil organisms and emphasis on its toxicological effects would potentially explicate its role as an environmental contaminant.

  17. Organic additives stabilize RNA aptamer binding of malachite green.

    PubMed

    Zhou, Yubin; Chi, Hong; Wu, Yuanyuan; Marks, Robert S; Steele, Terry W J

    2016-11-01

    Aptamer-ligand binding has been utilized for biological applications due to its specific binding and synthetic nature. However, the applications will be limited if the binding or the ligand is unstable. Malachite green aptamer (MGA) and its labile ligand malachite green (MG) were found to have increasing apparent dissociation constants (Kd) as determined through the first order rate loss of emission intensity of the MGA-MG fluorescent complex. The fluorescent intensity loss was hypothesized to be from the hydrolysis of MG into malachite green carbinol base (MGOH). Random screening organic additives were found to reduce or retain the fluorescence emission and the calculated apparent Kd of MGA-MG binding. The protective effect became more apparent as the percentage of organic additives increased up to 10% v/v. The mechanism behind the organic additive protective effects was primarily from a ~5X increase in first order rate kinetics of MGOH→MG (kMGOH→MG), which significantly changed the equilibrium constant (Keq), favoring the generation of MG, versus MGOH without organic additives. A simple way has been developed to stabilize the apparent Kd of MGA-MG binding over 24h, which may be beneficial in stabilizing other triphenylmethane or carbocation ligand-aptamer interactions that are susceptible to SN1 hydrolysis.

  18. The catalytic oxidation of malachite green by the microwave-Fenton processes.

    PubMed

    Zheng, Huaili; Zhang, Huiqin; Sun, Xiaonan; Zhang, Peng; Tshukudu, Tiroyaone; Zhu, Guocheng

    2010-01-01

    Catalytic oxidation of malachite green using the microwave-Fenton process was investigated. 0% of malachite green de-colorization using the microwave process and 23.5% of malachite green de-colorization using the Fenton process were observed within 5 minutes. In contrast 95.4% of malachite green de-colorization using the microwave-Fenton was observed in 5 minutes. During the microwave-Fenton process, the optimum operating conditions for malachite green de-colorization were found to be 3.40 of initial pH, 0.08 mmol/L of Fe2+ concentration and 12.5 mmol/L of H2O2 concentration. Confirmatory tests were carried out under the optimum conditions and the COD removal rate of 82.0% and the de-colorization rate of 99.0% were observed in 5 minutes. The apparent kinetics equation of -dC/dt=0.0337 [malachite green]0.9860[Fe2+)]0.8234[H2O2]0.1663 for malachite green de-colorization was calculated, which implied that malachite green was the dominant factor in determining the removal efficiency of malachite green based on microwave-Fenton process.

  19. Preconcentration and spectrophotometric determination of low concentrations of malachite green and leuco-malachite green in water samples by high performance solid phase extraction using maghemite nanoparticles.

    PubMed

    Afkhami, Abbas; Moosavi, Razieh; Madrakian, Tayyebeh

    2010-07-15

    A novel and sensitive extraction procedure using maghemite nanoparticles (gamma-Fe(2)O(3)) modified with sodium dodecyl sulfate (SDS), as an efficient solid phase, was developed for removal, preconcentration and spectrophotometric determination of trace amounts of malachite green (MG) and leuco-malachite green (LMG). Combination of nanoparticle adsorption and easily magnetic separation was used to extraction and desorption of MG and LMG. The adsorption capacity was evaluated using both the Langmuir and Freundlich adsorption isotherm models. Maghemite nanoparticles were prepared by co-precipitation method and their surfaces were modified by SDS. The size and properties of the produced maghemite nanoparticles was determined by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and BET analysis. MG and LMG became adsorbed at pH 3.0. LMG was oxidized to MG by adsorption on maghemite nanoparticles. The adsorbed MG was then desorbed and determined spectrophotometrically. The calibration graph was linear in the range 0.50-250.00 ng mL(-1) of MG and LMG with a correlation coefficient of 0.9991. The detection limit of the method for determination of MG was 0.28 ng mL(-1) and the relative standard deviation (R.S.D.) for 10.00 and 50.00 ng mL(-1) of malachite green was 1.60% (n=3) and 0.86% (n=5), respectively. A preconcentration factor of 50 was achieved in this method. The Langmuir adsorption capacity (q(max)) was found to be 227.3 mg g(-1) of the adsorbent. The method was applied to the determination of MG in fish farming water samples.

  20. Competitive adsorption of malachite green and Pb ions on natural zeolite.

    PubMed

    Wang, Shaobin; Ariyanto, Eko

    2007-10-01

    A natural zeolite was employed as adsorbent for removal of malachite green and Pb(2+) ions from aqueous solution. A batch system was applied to study the adsorption behaviour of the dye and heavy metal in single and binary systems on the natural zeolite. Kinetic studies indicate that malachite green and Pb(2+) adsorption on the natural zeolite in a single component system follows the first-order kinetics and the adsorption is diffusion process with single-stage for Pb(2+) and two-stage for malachite green. For the single system, malachite green adsorption isotherm follows the Langmuir model while Pb adsorption follows the Freundlich isotherm. The adsorption capacities of malachite green and Pb at 30 degrees C, pH 6 are 5x10(-5) and 10x10(-5)mol/g, respectively. In the binary system, malachite green and Pb(2+) exhibit competitive adsorption on the natural zeolite. The adsorption is reduced to 90 and 80% of single component of Pb(2+) and malachite green, respectively. However, the total adsorption is higher. In the binary system, Pb(2+) exhibits relative higher affinity and selectivity to be adsorbed on zeolite. The dynamic adsorption of malachite green and Pb(2+) still follows the first-order kinetics.

  1. Potential toxicity and affinity of triphenylmethane dye malachite green to lysozyme.

    PubMed

    Ding, Fei; Li, Xiu-Nan; Diao, Jian-Xiong; Sun, Ye; Zhang, Li; Ma, Lin; Yang, Xin-Ling; Zhang, Li; Sun, Ying

    2012-04-01

    Malachite green is a triphenylmethane dye that is used extensively in many industrial and aquacultural processes, generating environmental concerns and health problems to human being. In this contribution, the complexation between lysozyme and malachite green was verified by means of computer-aided molecular modeling, steady state and time-resolved fluorescence, and circular dichroism (CD) approaches. The precise binding patch of malachite green in lysozyme has been identified from molecular modeling and ANS displacement, Trp-62, Trp-63, and Trp-108 residues of lysozyme were earmarked to possess high-affinity for this dye, the principal forces in the lysozyme-malachite green adduct are hydrophobic and π-π interactions. Steady state fluorescence proclaimed the complex of malachite green with lysozyme yields quenching through static type, which substantiates time-resolved fluorescence measurements that lysozyme-malachite green conjugation formation has an affinity of 10(3)M(-1). Moreover, via molecular modeling and also CD data, we can safely arrive at a conclusion that the polypeptide chain of lysozyme partially destabilized upon complexation with malachite green. The data emerged here will help to further understand the toxicological action of malachite green in human body.

  2. [Studies on light catalysis oxidation degradation of Malachite Green by Photo-Fenton reagent].

    PubMed

    Zheng, Huai-li; Peng, De-jun; Li, Hong; Li, Xiao-hong; Wang, Bai-xue; Xie, Li-guo

    2007-05-01

    In the present paper, light catalysis oxidation degradation of Malachite Green by Photo-Fenton reagent was researched. The influences of various parameters such as the wave length-absorbency curve of Malachite Green, the concentration-absorbency curve of Malachite Green, initial pH, optimum dosage of Fe2+, optimum dosage of H2O2, different light sources and cation-exchange resin, on dye degradation were researched. Through numerous experiments, the optimum condition for Malachite Green degradation was given. Under the optimal conditions, the sun light can promote this reaction apparently and the reaction time can greatly be shortened too. After the cation-exchange resin was introduced into Fenton system, the activation of Fenton reagent for degradation reaction was enhanced to a great extent, and the degradation effect of Malachite Green was better.

  3. Resonant impulsive-stimulated Raman scattering on malachite green

    SciTech Connect

    Chesnoy, J.; Mokhtari, A.

    1988-10-01

    We have studied in the femtosecond regime the transient dynamics of dichroism (anisotropic absorption), birefringence, and frequency shift induced by an intense femtosecond pump beam in the dye malachite green in solution. Vibrational quantum beats were observed superimposed on the saturated absorption and dispersion signals and quantitatively explained in terms of impulsive-stimulated Raman scattering close to an electronic resonance. The selectivity for observation of the vibrations in the two electronic states is described for the different experimental schemes. We discuss the access to vibrational and electronic dynamics in both ground and excited electronic states and compare the possibilities to those of previous techniques.

  4. Morphological changes in vesicles and release of an encapsulated compound triggered by a photoresponsive Malachite Green leuconitrile derivative.

    PubMed

    Uda, Ryoko M; Hiraishi, Eri; Ohnishi, Ryo; Nakahara, Yoshio; Kimura, Keiichi

    2010-04-20

    Photoinduced morphological changes in phosphatidylcholine vesicles are triggered by a Malachite Green leuconitrile derivative dissolved in the lipidic membrane, and are observed at Malachite Green derivative/lipid ratios <5 mol %. This Malachite Green derivative is a photoresponsive compound that undergoes ionization to afford a positive charge on the molecule by UV irradiation. The Malachite Green derivative exhibits amphiphilicity when ionized photochemically, whereas it behaves as a lipophilic compound under dark conditions. Cryo-transmission electron microscopy was used to determine vesicle morphology. The effects of the Malachite Green derivative on vesicles were studied by dynamic light scattering and fluorescence resonance energy transfer. Irradiation of vesicles containing the Malachite Green derivative induces nonspherical vesicle morphology, fusion of vesicles, and membrane solubilization, depending on conditions. Furthermore, irradiation of the Malachite Green derivative induces the release of a vesicle-encapsulated compound.

  5. Synthesis and characterization of N-demethylated metabolites of malachite green and leucomalachite green.

    PubMed

    Cho, Bongsup P; Yang, Tianle; Blankenship, Lonnie R; Moody, Joanna D; Churchwell, Mona; Beland, Frederick A; Culp, Sandra J

    2003-03-01

    Malachite green (MG), a triphenylmethane dye used to treat fungal and protozoan infections in fish, undergoes sequential oxidation to produce various N-demethylated derivatives (monodes-, dides(sym)-, dides(unsym)-, trides-, and tetrades-) both before and after reduction to leucomalachite green (LMG). The close structure resemblance of the metabolites with aromatic amine carcinogens implicates a potential genotoxicity from exposure to MG. The availability of the synthetic standards is important for metabolic and DNA adduct studies of MG. This paper describes a simple and versatile method for the synthesis of MG, LMG, and their N-demethylated metabolites. The synthesis involves a coupling of 4-(dimethylamino)benzophenone or 4-nitrobenzophenone with the aryllithium reagents derived from appropriately substituted 4-bromoaniline derivatives, followed by treatment with HCl in methanol. The resulting cationic MG and their leuco analogues showed systematic UV/vis spectral and tandem mass fragmentation patterns consistent with sequential N-demethylation. The extensive (1)H and (13)C spectral assignments of the metabolites were aided by the availability of (13)C(7)-labeled MG and LMG. The results indicate the existence of a resonance structure with the cationic charge located in the central methane carbon (C(7)). The synthetic procedure is general in scope so that it can be extended to the preparation of N-demethylated metabolites of other structurally related N-methylated triphenylmethane dyes.

  6. Permanent draft genome of the malachite-green-tolerant bacterium Rhizobium sp. MGL06.

    PubMed

    Liu, Yang; Wang, Runping; Zeng, Runying

    2014-12-01

    Rhizobium sp. MGL06, the first Rhizobium isolate from a marine environment, is a malachite-green-tolerant bacterium with a broader salinity tolerance (range: 0.5% to 9%) than other rhizobia. This study sequences and annotates the draft genome sequence of this strain. Genome sequence information provides a basis for analyzing the malachite green tolerance, broad salinity adaptation, nitrogen fixation properties, and taxonomic classification of the isolate.

  7. Malachite green and chloramphenicol in aquatic products from regions around Dongting Lake in Hunan, China.

    PubMed

    He, Jiang; Cui, Jingzhen

    2016-01-01

    Aquatic products are important sources of animal proteins in human diet, especially in developing countries. As such, the safety of aquatic products is of primary concern. In this study, a standard method is used to detect malachite green (MG) and chloramphenicol (CAP) and to analyse the contents of these banned chemicals in turtle, mandarin fish and grass carp sampled from the region surrounding Dongting Lake area in Hunan, China. Results showed that 10.6% of the samples were MG-positive, most of them turtles. CAP was found in 8.3% of the samples, mostly in mandarin fish. These data indicated that these banned substances are still used in the surveyed area. Hence, adequate strategies must be implemented by the local government to control these banned substances.

  8. Degradation pathway of malachite green in a novel dual-tank photoelectrochemical catalytic reactor.

    PubMed

    Diao, Zenghui; Li, Mingyu; Zeng, Fanyin; Song, Lin; Qiu, Rongliang

    2013-09-15

    A novel dual-tank photoelectrochemical catalytic reactor was designed to investigate the degradation pathway of malachite green. A thermally formed TiO₂/Ti thin film electrode was used as photoanode, graphite was used as cathode, and a saturated calomel electrode was employed as the reference electrode in the reactor. In the reactor, the anode and cathode tanks were connected by a cation exchange membrane. Results showed that the decolorization ratio of malachite green in the anode and cathode was 98.5 and 96.5% after 120 min, respectively. Malachite green in the two anode and cathode tanks was oxidized, achieving the bipolar double effect. Malachite green in both the anode and cathode tanks exhibited similar catalytic degradation pathways. The double bond of the malachite green molecule was attacked by strong oxidative hydroxyl radicals, after which the organic compound was degraded by the two pathways into 4,4-bis(dimethylamino) benzophenone, 4-(dimethylamino) benzophenone, 4-(dimethylamino) phenol, and other intermediate products. Eventually, malachite green was degraded into oxalic acid as a small molecular organic acid, which was degraded by processes such as demethylation, deamination, nitration, substitution, addition, and other reactions.

  9. A study of the interaction between malachite green and lysozyme by steady-state fluorescence.

    PubMed

    Ding, Fei; Liu, Wei; Liu, Feng; Li, Zhi-Yuan; Sun, Ying

    2009-09-01

    The interaction of a N-methylated diaminotriphenylmethane dye, malachite green, with lysozyme was investigated by fluorescence spectroscopic techniques under physiological conditions. The binding parameters have been evaluated by fluorescence quenching methods. The results revealed that malachite green caused the fluorescence quenching of lysozyme through a static quenching procedure. The thermodynamic parameters like DeltaH and DeltaS were calculated to be -15.33 kJ mol(-1) and 19.47 J mol(-1) K(-1) according to van't Hoff equation, respectively, which proves main interaction between malachite green and lysozyme is hydrophobic forces and hydrogen bond contact. The distance r between donor (lysozyme) and acceptor (malachite green) was obtained to be 3.82 nm according to Frster's theory. The results of synchronous fluorescence, UV/vis and three-dimensional fluorescence spectra showed that binding of malachite green with lysozyme can induce conformational changes in lysozyme. In addition, the effects of common ions on the constants of lysozyme-malachite green complex were also discussed.

  10. Treatment of malachite green-containing wastewater using poultry feathers as adsorbent.

    PubMed

    Beak, Mi H; Ijagbemi, Christianah O; Kim, Dong S

    2009-04-01

    The feasibility of using feathers, a waste from poultry as an absorbent for malachite green in dye wastewater was studied. The batch adsorption tests were shown to be influenced by the concentration of the dye, reaction temperature, solution pH, and pre-treatment with ethanol. In order to establish the equilibrium state of the process, a kinetic study was conducted for an optimal practice of adsorption treatment process. The adsorption reached equilibrium within 120 min in the range of dye concentration studied. It was found that the adsorption rate increases especially at low concentrations of dye and the adsorption data fitted well to the first-order reaction kinetics over all dye concentration range. Absolute amount of adsorbed malachite green at equilibrium condition decreased as concentration decreases. Adsorption of malachite green on poultry feathers fitted well to the Langmuir isotherm model. As temperature increases, the adsorbed amount of malachite green at equilibrium also increased, indicating an endothermic adsorption reaction. In addition, the color removal of malachite green rapidly increased with increase in dye's water pH. The pre-treatment of adsorbent with ethanol produced initial slow rate of malachite green removal but after about 100 min of reaction time, same removal rate was observed compare with the untreated feathers.

  11. A sensitive electrochemical impedance immunosensor for determination of malachite green and leucomalachite green in the aqueous environment.

    PubMed

    Zhu, Dan; Li, Qiangqiang; Pang, Xiumei; Liu, Yue; Wang, Xue; Chen, Gang

    2016-08-01

    Application of malachite green (MG) and leucomalachite green (LMG) in fish farm water causes an environmental problem. This study proposes for the first time a sensitive and convenient electrochemical impedance spectroscopy (EIS) method for determining MG and LMG by a bovine serum albumin-decorated gold nanocluster (BSA-AuNC)/antibody composite film-based immunosensor. In order to improve the analytical performance, the glassy carbon electrode (GCE) was modified with 1, 4-phenylenediamine to form a stable layer, and then, BSA-AuNCs were covalently bound to the GCE. An adequate quantity of the polyclonal antibody of LMG was immobilized onto the surface of the BSA-AuNCs by the chemical reaction of EDC/NHS. The sensors can respond to the specific target based on specific covalent bonding. The experimental parameters, such as the pH, incubating concentration, and time, have been investigated and optimized. The calibration curve for LMG was linear in the range of 0.1~10.0 ng/mL with the limit of detection (LOD) 0.03 ng/mL. Furthermore, the sum of MG and LMG was detected in fish farm water by MG reduction. The recovery was between 89.7 % and 99.2 % in spiked samples. The EC sensor method was also compared with the ELISA method and validated by the LC-MS/MS method, which proves its great promise as a field instrument for the rapid monitoring of MG and LMG pollution. Graphical abstract 1, 4-Phenylenediamine and BSA-AuNC/antibody-decorated glassy carbon electrodes have been used for the impedimetric detection of the sum of malachite green and leucomalachite green via specific immuno-binding.

  12. Biological decolorization of malachite green by Deinococcus radiodurans R1.

    PubMed

    Lv, Guo-Ying; Cheng, Jian-Hui; Chen, Xiao-Yang; Zhang, Zuo-Fa; Fan, Lei-Fa

    2013-09-01

    Cultures of Deinococcus radiodurans R1 were observed to decolorize malachite green (MG) dye. The effects of various factors on decolorization efficiency were investigated. The optimal decolorization temperature and pH ranges were 25-50°C and 6.0-8.0, respectively. With increasing initial MG concentration, the decolorization efficiency decreased, and the kinetic parameters, R(MG,max) and K(m) were 416.7 mg-MG/g-cell/h and 1033.7 mg/L, respectively. The D. radiodurans R1 cells were capable of tolerating and rapidly degrading high concentrations of the dye. When MG concentration was 200 mg/L, decolorization efficiency was up to 97.2% within 30 min. The intermediate products of MG biodegradation were 4-(dimethylamino)phenol and 4-(dimethylamino)benzophenone, as identified by gas chromatography/mass spectrometry analysis. Toxicity tests indicated that D. radiodurans R1 did not detoxify an MG solution completely, but clearly reduced its toxicity. This study demonstrated that this strain was an efficient degrader compared to other microorganisms.

  13. Permethylated-β-Cyclodextrin Capped CdTe Quantum Dot and its Sensitive Fluorescence Analysis of Malachite Green.

    PubMed

    Cao, Yujuan; Wei, Jiongling; Wu, Wei; Wang, Song; Hu, Xiaogang; Yu, Ying

    2015-09-01

    In the present work, the CdTe quantum dots were covalently conjugated with permethylated-β-cyclodextrin (OMe-β-CD) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride as cross-linking reagent. The obtained functional quantum dots (OMe-β-CD/QDs) showed highly luminescent, water solubility and photostability as well as good inclusion ability to malachite green. A sensitive fluorescence method was developed for the analysis of malachite green in different samples. The good linearity was 2.0 × 10(-7)-1.0 × 10(-5) mol/L and the limit of detect was 1.7 × 10(-8) mol/L. The recoveries for three environmental water samples were 92.0-108.2 % with relative standard deviation (RSD) of 0.24-1.87 %, while the recovery for the fish sample was 94.3 % with RSD of 1.04 %. The results showed that the present method was sensitive and convenient to determine malachite green in complex samples. Graphical Abstract The analytical mechanism of OMe-β-CD/QDs and its linear response to MG.

  14. A nanosilver-based spectrophotometric method for determination of malachite green in surface water samples.

    PubMed

    Sahraei, R; Farmany, A; Mortazavi, S S; Noorizadeh, H

    2013-07-01

    A new spectrophotometric method is reported for the determination of nanomolar level of malachite green in surface water samples. The method is based on the catalytic effect of silver nanoparticles on the oxidation of malachite green by hexacyanoferrate (III) in acetate-acetic acid medium. The absorbance is measured at 610 nm with the fixed-time method. Under the optimum conditions, the linear range was 8.0 × 10(-9)-2.0 × 10(-7) mol L(-1) malachite green with a correlation coefficient of 0.996. The limit of detection (S/N = 3) was 2.0 × 10(-9) mol L(-1). Relative standard deviation for ten replicate determinations of 1.0 × 10(-8) mol L(-1) malachite green was 1.86%. The method is featured with good accuracy and reproducibility for malachite green determination in surface water samples without any pre-concentration and separation step.

  15. Disrupting actions of bisphenol A and malachite green on growth hormone receptor gene expression and signal transduction in seabream.

    PubMed

    Jiao, Baowei; Cheng, Christopher H K

    2010-06-01

    Environmental estrogen could mimic natural estrogens thereby disrupting the endocrine systems of human and animals. The actions of such endocrine disruptors have been studied mainly on reproduction and development. However, estrogen could also affect the somatotropic axis via multiple targets such as growth hormone (GH). In the present study, two endocrine disruptors were chosen to investigate their effects on the expression level and signal transduction of growth hormone receptor (GHR) in fish. Using real-time PCR, it was found that exposure to both the estrogenic (bisphenol A) and anti-estrogenic (malachite green) compounds could attenuate the expression levels of GHR1 and GHR2 in black seabream (Acanthopagrus schlegeli) hepatocytes. The expression level of IGF-I, the downstream effector of GHR activation in the liver, was decreased by bisphenol A but not by malachite green. Luciferase reporter assay of the beta-casein promoter was used to monitor GHR signaling in transfected cells. In the fish liver cell line Hepa-T1, both GHR1 and GHR2 signaling were attenuated by bisphenol A and malachite green. This attenuation could only occur in the presence of estrogen receptor, indicating that these agents probably produce their actions via the estrogen receptor. Results of the present study demonstrated that estrogenic or anti-estrogenic compounds could down-regulate the somatotropic axis in fish by affecting both the gene expression and signaling of GHR. In view of the increasing prevalence of these compounds in the environment, the impact on fish growth and development both in the wild and in aquaculture would be considerable.

  16. Investigation kinetics mechanisms of adsorption malachite green onto activated carbon.

    PubMed

    Onal, Y; Akmil-Başar, C; Sarici-Ozdemir, C

    2007-07-19

    Lignite was used to prepare activated carbon (T3K618) by chemical activation with KOH. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by t-plot based on N2 adsorption isotherm. BET surface area of activated carbon is determined as 1000 m2/g. Adsorption capacity of malachite green (MG) onto T3K618 activated carbon was investigated in a batch system by considering the effects of various parameters like initial concentration (100, 150 and 200 mg/L) and temperature (25, 40 and 50 degrees C). The adsorption process was relatively fast and equilibrium was reached after about 20 min for 100, 150 mg/L at all adsorption temperature. Equilibrium time for 200 mg/L was determined as 20 min and 40 min at 298, 313 and 323 K, respectively. Simple mass and kinetic models were applied to the experimental data to examine the mechanisms of adsorption and potential rate controlling steps such as external mass transfer, intraparticle diffusion. Pseudo second-order model was found to explain the kinetics of MG adsorption most effectively. It was found that both mass transfer and pore diffusion are important in determining the adsorption rates. The intraparticle diffusion rate constant, external mass transfer coefficient, film and pore diffusion coefficient at various temperatures were evaluated. The activation energy (Ea) was determined as 48.56, 63.16, 67.93 kJ/mol for 100, 150, 200 mg/L, respectively. The Langmiur and Freundlich isotherm were used to describe the adsorption equilibrium studies at different temperatures. Langmiur isotherm shows better fit than Freundlich isotherm in the temperature range studied. The thermodynamic parameters, such as DeltaG degrees, DeltaS and DeltaH degrees were calculated. The thermodynamics of dyes-T3K618 system indicates endothermic process.

  17. Improved removal of malachite green from aqueous solution using chemically modified cellulose by anhydride.

    PubMed

    Zhou, Yanmei; Min, Yinghao; Qiao, Han; Huang, Qi; Wang, Enze; Ma, Tongsen

    2015-03-01

    Cellulose modified with maleic (M) and phthalic (P) anhydride, to be named CMA and CPA, were tested as feasible adsorbents for the removal of malachite green from aqueous solution. At the same time, the uptake ability of natural cellulose was also studied for comparison. The structure of material was characterized by FT-IR and XRD. The effects of solution pH, initial dye concentration, contact time and temperature were investigated in detail by batch adsorption experiments. The kinetic and isotherm studies suggested that the adsorption followed the pseudo-second-order model and Langmuir isotherm. The maximum adsorption capacity on CMA and CPA were 370 mg g(-1) and 111 mg g(-1), respectively. Furthermore, the thermodynamics studies indicated the spontaneous nature of adsorption of malachite green on adsorbents. All the studied results showed that the modified cellulose could be used as effective adsorption material for the removal of malachite green from aqueous solutions.

  18. Study of Characterization of Pure and Malachite Green Doped Samples Using Spectroscopic Studies

    NASA Astrophysics Data System (ADS)

    Mishra, Jyoti; Mishra, Pankaj K.; Khare, P. K.

    2011-07-01

    This paper describes the results of SEM, EDX, UV-vis and TSDC study of malachite green doped PVK thermelectrets. TSDC study has been carried out in the temperature range 300 °C to 1500 °C with four different polarizing fields. One peak was observed at 110±10 °C which shifts toward high temperature with the increase in polarizing field. The activation energy found by initial rise method are 0.27±0.02 eV for pure and 0.40±0.03 eV for malachite green doped PVK thermoelectrets. Spectroscopic study concluded that impregnation of malachite green in polymer matrix forms charge transfer complexes.

  19. Investigation on the interaction between an antimicrobial in aquaculture, malachite green and hemocyanin from Mud Crab Scylla paramamosain

    NASA Astrophysics Data System (ADS)

    Li, Zhenxing; Tang, Boping; Zhang, Hongmei

    2015-01-01

    Interaction between malachite green and hemocyanin of crab plays a crucial role in the metabolism, distribution, and efficacy of toxic dyes in aquaculture. The mechanism of interaction between malachite green and Hc from mud crab was studied by using multi-spectral methods and molecular modeling in this work. The spectroscopic and thermodynamic data show that the interaction is a spontaneous process with the estimated enthalpy and entropy changes of -14.85(±1.86) kJ mol-1 and 30.38(±5.21) J mol-1 K-1, respectively. The binding sites of malachite green in hemocyanin mainly locate in the interface of protein. The hydrophobic and electrostatic forces are the primary contributors to the interaction between hemocyanin and malachite green. The results of ultraviolet-vis absorbance, circular dichroism, and synchronous fluorescence spectroscopy suggest that the binding of malachite green to hemocyanin induces some conformational changes of protein.

  20. Investigation on the interaction between an antimicrobial in aquaculture, malachite green and hemocyanin from mud crab Scylla paramamosain.

    PubMed

    Li, Zhenxing; Tang, Boping; Zhang, Hongmei

    2015-01-25

    Interaction between malachite green and hemocyanin of crab plays a crucial role in the metabolism, distribution, and efficacy of toxic dyes in aquaculture. The mechanism of interaction between malachite green and Hc from mud crab was studied by using multi-spectral methods and molecular modeling in this work. The spectroscopic and thermodynamic data show that the interaction is a spontaneous process with the estimated enthalpy and entropy changes of -14.85(±1.86) kJ mol(-1) and 30.38(±5.21) J mol(-1) K(-1), respectively. The binding sites of malachite green in hemocyanin mainly locate in the interface of protein. The hydrophobic and electrostatic forces are the primary contributors to the interaction between hemocyanin and malachite green. The results of ultraviolet-vis absorbance, circular dichroism, and synchronous fluorescence spectroscopy suggest that the binding of malachite green to hemocyanin induces some conformational changes of protein.

  1. Site-Dependent Fluorescence Decay of Malachite Green Doped in Onion Cell

    NASA Astrophysics Data System (ADS)

    Nakatsuka, Hiroki; Sekine, Masaya; Suzuki, Yuji; Hattori, Toshiaki

    1999-03-01

    Time-resolved fluorescence measurements of malachite green dye moleculesdoped in onion cells were carried out.The fluorescence decay time was dependent on the individual cell and on theposition of the dye in a cell, which reflect the microscopic dynamics of each boundsite.Upon cooling, the decay time increased and this increase was accelerated ataround the freezing point of the onion cell.

  2. [Biosorption of crystal violet and malachite green by Rhodotorula graminis Y-5].

    PubMed

    Hu, Rong; Huang, Jian-Bo; Yang, Zhou-Ping; Cheng, Zi-Zhang; Jing, De-Jun; Huang, Qian-Ming

    2011-12-01

    With a shaker, this paper studied the characteristics of the biosorption of crystal violet and malachite green by Rhodotorula graminis Y-5 under different adsorption time, initial pH, and temperature, as well as the desorption and recycling use of the dyes. The biosorption of crystal violet and malachite green by R. graminis Y-5 had the peaks (93.8% and 87.7%, respectively) at pH 7.0, dye concentration 50 mg x L(-1), 150 r x min(-1), 30 degrees C, and lasting 10 hours. After desorption, the biosorption rate of crystal violet and malachite green by R. graminis was 85.5% and 78.5%, respectively, indicating that the biosorption of crystal violet and malachite green was reversible, and the recycling use of the dyes by R. graminis was quite good, i. e., the dyes were renewable and could be recycled. Biosorption could be the mechanism of the decolorization of the dyes. The dyes were mostly adsorbed on the R. graminis surface -OH. The adsorption process was fast, efficient, and reversible, suggesting that R. graminis had a high potential for waste water treatment.

  3. Solvent dependence of ultrafast ground state recovery of the triphenylmethane dyes, brilliant green and malachite green

    NASA Astrophysics Data System (ADS)

    Nagasawa, Yutaka; Ando, Yoshito; Okada, Tadashi

    1999-10-01

    We have studied femtosecond ground state recovery dynamics of the triphenylmethane dyes brilliant green (BG) and malachite green (MG) by pump-probe spectroscopy at the center wavelength of 635 nm with a time resolution of 33 fs. The ultrafast recovery of the ground state bleach was highly nonexponential and depended on the solvent viscosity, although all time constants were shorter than the solvation times obtained from other measurements. We observed a plateau or a rise component in the signal, which indicates an intermediate state. The rise time showed a viscosity dependence, even in the ultrafast time domain. It should be noted that the decay times were always longer for BG than MG, while the rise time did not show a solute dependence. The torsional motion of the amino-substituted phenyl group may be involved in the ultrafast process to the intermediate state, but lack of a solute dependence indicates that only a small conformational change is involved.

  4. Demonstration [sic] of a System for Removing Malachite Green : Final Report.

    SciTech Connect

    Marking, Leif L.

    1989-04-01

    Activated carbon has been used effectively to remove tastes, odors, and contaminants from public water supplies. The adsorption efficiency is influenced by the size of carbon granules, flow rate, column depth, and retention time. A study was designed to (1) determine the type of filter and kind of carbon that was most efficient and (2) demonstrate that carbon filters can be used to remove malachite green from water used for egg incubation or to hold adult salmon before spawning. Minicolumn simulation studies showed that 8 /times/ 30 mesh granular carbon manufactured from bituminous coal was effective for continuously removing malachite green from water for 230 days at a flow rate of 500 gpm and for 62 days at a flow rate of 1000 gpm. The removal capacity at the slower flow rate was 69 mg of malachite green per gram of carbon. A filter system that contained 20,000 pounds of activated carbon in each of two chambers was effective for removal of malachite green from treated water in adult salmon holding ponds at flows of 500 gpm and greater. The removal efficiency was 99.8% after 105 hours of operation, and the adsorption capacity of the system was projected to be 20 or more years of routine hatchery operation. A filter system that contained 2000 pounds of activated carbon in each of two chambers was effective for removal of malachite green from treated water in salmon egg incubation units at the designated flow rate of 50 gpm and also at faster flow rates. 14 refs., 5 figs., 6 tabs.

  5. Isolation of a malachite green-degrading Pseudomonas sp. MDB-1 strain and cloning of the tmr2 gene.

    PubMed

    Li, Lian-tai; Hong, Qing; Yan, Xin; Fang, Gui-hua; Ali, Shinawar Waseem; Li, Shun-peng

    2009-11-01

    The release of malachite green, a commonly used triphenylmethane dye, into the environment is causing increasing concern due to its toxicity, mutagenicity, and carcinogenicity. A bacterial strain that could degrade malachite green was isolated from the water of an aquatic hatchery. It was identified as a Pseudomonas sp. based on the morphological, physiological, and biochemical characteristics, as well as the analysis of 16S rRNA gene sequence and designated as MDB-1. This strain was capable of degrading both malachite green and leucomalachite green, as well as other triphenylmethane dyes including Crystal Violet and Basic Fuchsin. The gene tmr2, encoding the triphenylmethane reductase from MDB-1, was cloned, sequenced and effectively expressed in E. coli. These results highlight the potential of this bacterium for the bioremediation of aquatic environments contaminated by malachite green.

  6. Enhanced sensitive immunoassay: noncompetitive phage anti-immune complex assay for the determination of malachite green and leucomalachite green.

    PubMed

    Dong, Jie-Xian; Xu, Chao; Wang, Hong; Xiao, Zhi-Li; Gee, Shirley J; Li, Zhen-Feng; Wang, Feng; Wu, Wei-Jian; Shen, Yu-Dong; Yang, Jin-Yi; Sun, Yuan-Ming; Hammock, Bruce D

    2014-08-27

    To develop a more sensitive immunoassay for malachite green (MG) and leucomalachite green (LMG), we identified the immunocomplex binding phage-borne peptides for use in the noncompetitive phage anti-immunocomplex assay (PHAIA). An anti-LMG monoclonal antibody (mAb) was used to select immunocomplex binding peptides from a circular random eight-amino-acid phage-displayed library. After three rounds of panning-elution, five peptides that bound the LMG-mAb immunocomplex were obtained. One of the phage-borne peptide clones that resulted in an assay with the highest sensitivity was chosen for further research. The concentration of LMG producing 50% of the saturated signal and the limit of detection of the assay were 7.02 and 0.55 ng/mL, respectively, with a linear range of 1.35 to 21.56 ng/mL. The PHAIA based on the same antibody was 16 times more sensitive compared to the competitive immunoassay. PHAIA was used to analyze LMG, MG, and two mixtures of spiked fish samples, with validation by high-performance liquid chromatography (HPLC) with fluorescence detector. Results showed a good correlation (R(2)LMG = 0.9841; R(2)MG = 0.993; R(2)Mixture = 0.9903) between the data of PHAIA and HPLC, thus the assay was an efficient method for monitoring food safety.

  7. Partial degradation mechanisms of malachite green and methyl violet B by Shewanella decolorationis NTOU1 under anaerobic conditions.

    PubMed

    Chen, C-H; Chang, C-F; Liu, S-M

    2010-05-15

    This work demonstrated that Shewanella decolorationis NTOU1 decolorized 200 mg l(-1) of crystal violet, malachite green, or methyl violet B within 2-11h under anaerobic conditions at 35 degrees C. The initial color removal rate of malachite green was highest, while that of methyl violet was lowest. GC/MS analyses of the intermediate compounds produced during and after decolorization of malachite green and methyl violet B suggested that biodegradation of these dyes involved reduction to leuco form, N-demethylation, and reductive splitting of the triphenyl rings. The number of N-methylated groups of these dyes might have influenced decolorization rates and the reductive splitting of the triphenyl rings of these dyes. Cytotoxicity and antimicrobial test data showed that malachite green and methyl violet B solution (100 mg l(-1)) were toxic. Toxicity of the dyes decreased after their decolorization, but further incubation resulted in increased toxicity.

  8. Biomimetic ELISA detection of malachite green based on magnetic molecularly imprinted polymers.

    PubMed

    Li, Lu; Lin, Zheng-Zhong; Peng, Ai-Hong; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

    2016-11-01

    A direct competitive enzyme-linked immunosorbent assay (ELISA) method was used for the detection of malachite green (MG) with a high sensitivity and selectivity using magnetic molecularly imprinted polymers (MMIPs) as a bionic antibody. MMIPs were prepared through emulsion polymerization using Fe3O4 nanoparticles as magnetic nuclei, MG as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent and span-80/tween-80 as mixed emulsifiers. The MMIPs were characterized by scanning electron micrographs (SEM), thermal-gravimetric analyzer (TGA), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. A high magnetic saturation value of 54.1emug(-1) was obtained, resulting in rapid magnetic separation of MMIPs with an external magnet. The IC50 of the established ELISA method was 20.1μgL(-1) and the detection limit (based on IC85) was 0.1μgL(-1). The MMIPs exhibited high selective binding capacity for MG with cross-reactivities less than 3.9% for MG structural analogues. The MG spiking recoveries were 85.0%-106% with the relative standard deviations less than 4.7%. The results showed that the biomimetic ELISA method by using MMIPs as bionic antibody could be used to detect MG rapidly in fish samples with a high sensitivity and accuracy.

  9. Molecular recognition of malachite green by hemoglobin and their specific interactions: insights from in silico docking and molecular spectroscopy.

    PubMed

    Peng, Wei; Ding, Fei; Peng, Yu-Kui; Sun, Ying

    2014-01-01

    Malachite green is an organic compound that can be widely used as a dyestuff for various materials; it has also emerged as a controversial agent in aquaculture. Since malachite green is proven to be carcinogenic and mutagenic, it may become a hazard to public health. For this reason, it is urgently required to analyze this controversial dye in more detail. In our current research, the interaction between malachite green and hemoglobin under physiological conditions was investigated by the methods of molecular modeling, fluorescence spectroscopy, circular dichroism (CD) as well as hydrophobic ANS displacement experiments. From the molecular docking, the central cavity of hemoglobin was assigned to possess high-affinity for malachite green, this result was corroborated by time-resolved fluorescence and hydrophobic ANS probe results. The recognition mechanism was found to be of static type, or rather the hemoglobin-malachite green complex formation occurred via noncovalent interactions such as π-π interactions, hydrogen bonds and hydrophobic interactions with an association constant of 10(4) M(-1). Moreover, the results also show that the spatial structure of the biopolymer was changed in the presence of malachite green with a decrease of the α-helix and increase of the β-sheet, turn and random coil suggesting protein damage, as derived from far-UV CD and three-dimensional fluorescence. Results of this work will help to further comprehend the molecular recognition of malachite green by the receptor protein and the possible toxicological profiles of other compounds, which are the metabolites and ramifications of malachite green.

  10. TSDC and X-ray diffraction analysis of pure and malachite green sensitized polyvinyl carbazole films

    SciTech Connect

    Mishra, Pankaj Kumar; Kathal, Rachana; Mishra, Jyoti; Pandey, Hariom; Khare, P. K.

    2013-02-05

    This paper describes the method for investigating the electrical properties of high solids via the study of thermal relaxation effects and offers an alternative scheme to the conventional bridge methods or the current voltage temperature measurements. For standard TSD experiment, this is comparable to a dielectric loss measurement, the low equivalent frequency and high sensitivity (ability to detect dipole concentration). The activation energies found by initial rise method are 0.31 {+-} 0.02 eV for pure and 0.43 {+-} 0.03 eV for malachite green sensitized PVK thermoelectrets. The peak current charges and activation energy associated with the peaks are affected by concentration of malachite green and have been explained in terms of formation of charge transfer complexes and molecular aggregates. The microscopic origin of a given current spectrum is explained by comparing the predictions of the general theories regarding the main polarization processes with the experimental data.

  11. TSDC and X-ray diffraction analysis of pure and malachite green sensitized polyvinyl carbazole films

    NASA Astrophysics Data System (ADS)

    Mishra, Pankaj Kumar; Mishra, Jyoti; Kathal, Rachana; Pandey, Hariom; Khare, P. K.

    2013-02-01

    This paper describes the method for investigating the electrical properties of high solids via the study of thermal relaxation effects and offers an alternative scheme to the conventional bridge methods or the current voltage temperature measurements. For standard TSD experiment, this is comparable to a dielectric loss measurement, the low equivalent frequency and high sensitivity (ability to detect dipole concentration). The activation energies found by initial rise method are 0.31 ± 0.02 eV for pure and 0.43 ± 0.03 eV for malachite green sensitized PVK thermoelectrets. The peak current charges and activation energy associated with the peaks are affected by concentration of malachite green and have been explained in terms of formation of charge transfer complexes and molecular aggregates. The microscopic origin of a given current spectrum is explained by comparing the predictions of the general theories regarding the main polarization processes with the experimental data.

  12. Use of the reaction of malachite green with 11-molybdogermanic heteropolyacid

    SciTech Connect

    Mirzoyan, F.V.; Airiyan, E.K.; Tarayan, V.M.

    1985-05-01

    This paper presents the results of an investigation of the interaction of malachite green (MG) with molybdogermanic heteropolyacid (MGA) in a wide range of acidity and concentrations of the reacting componenets in order to establish the optimum conditions of formation and isolation of more highly substituted salts of MGA and to increase the sensitivity of the photometric determination of germanium. It is shown that 11-molybdogermanic acid interacts quantitatively with malachite green in a wide range of acidity, forming three solid phase compounds of different compositions, contining 2, 4, and 8 associated cations of the dye. The compound with composition 8:1 was used to develop a highly sensitive method of determining submicro- and microgram quantities of germanium after its extraction determination in the form of GeC1/sub 4/.

  13. Polyvinyl butyral films containing leuco-malachite green as low-dose dosimeters

    NASA Astrophysics Data System (ADS)

    Mai, Hoang Hoa; Solomon, H. M.; Taguchi, M.; Kojima, T.

    2008-04-01

    Thin films containing leuco-malachite green (LMG) dye in polyvinyl butyral (PVB) have been developed for dose measurements of a few hundreds Gy level. The film shows significant color change in the visible range, and the sensitivity of the film to absorbed dose was enhanced by addition of chloride-containing compounds, such as chloral hydrate or 2,2,2-trichloroethanol. The film is suitable as dosimeters for dose measurements, e.g. in food irradiation and environmental protection.

  14. Sensitive detection of malachite green and crystal violet by nonlinear laser wave mixing and capillary electrophoresis.

    PubMed

    Maxwell, Eric J; Tong, William G

    2016-05-01

    An ultrasensitive label-free antibody-free detection method for malachite green and crystal violet is presented using nonlinear laser wave-mixing spectroscopy and capillary zone electrophoresis. Wave-mixing spectroscopy provides a sensitive absorption-based detection method for trace analytes. This is accomplished by forming dynamic gratings within a sample cell, which diffracts light to create a coherent laser-like signal beam with high optical efficiency and high signal-to-noise ratio. A cubic dependence on laser power and square dependence on analyte concentration make wave mixing sensitive enough to detect molecules in their native form without the use of fluorescent labels for signal enhancement. A 532 nm laser and a 635 nm laser were used for malachite green and crystal violet sample excitation. The use of two lasers of different wavelengths allows the method to simultaneously detect both analytes. Selectivity is obtained through the capillary zone electrophoresis separation, which results in characteristic migration times. Measurement in capillary zone electrophoresis resulted in a limit of detection of 6.9 × 10(-10)M (2.5 × 10(-19) mol) for crystal violet and 8.3 × 10(-11)M (3.0 × 10(-20) mol) for malachite green at S/N of 2.

  15. Photodegradation of malachite green under simulated and natural irradiation: kinetics, products, and pathways.

    PubMed

    Yong, Li; Zhanqi, Gao; Yuefei, Ji; Xiaobin, Hu; Cheng, Sun; Shaogui, Yang; Lianhong, Wang; Qingeng, Wang; Die, Fang

    2015-03-21

    In this work photodegradation rates and pathways of malachite green were studied under simulated and solar irradiation with the goal of assessing the potential of photolysis as a removal mechanism in real aquatic environment. Factors influencing the photodegradation process were investigated, including pH, humic acid, Fe(2+), Ca(2+), HCO3(-), and NO3(-), of which favorable conditions were optimized by the orthogonal array design under simulated sunlight irradiation in the presence of dissolved oxygen. The degradation processes of malachite green conformed to pseudo first-order kinetics and their degradation rate constants were between 0.0062 and 0.4012 h(-1). Under solar irradiation, the decolorization efficiency of most tests can reach almost 100%, and relatively thorough mineralization could be observed. Forty degradation products were detected by liquid chromatography-mass spectrometry, and thirteen small molecular products were identified by gas chromatography-mass spectrometry. Based on the analyses of the degradation products and calculation of the frontier electron density, the pathways were proposed: decomposition of conjugated structure, N-demethylation reactions, hydroxyl addition reactions, the removal of benzene ring, and the ring-opening reaction. This study has provided a reference, both for photodegradation of malachite green and future safety applications and predictions of decontamination of related triphenylmethane dyes under real conditions.

  16. Green synthesized conditions impacting on the reactivity of Fe NPs for the degradation of malachite green

    NASA Astrophysics Data System (ADS)

    Huang, Lanlan; Luo, Fang; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2015-02-01

    This study investigates green tea extract synthesized conditions impacting on the reactivity of iron nanoparticles (Fe NPs) used for the degradation of malachite green (MG), including the volume ratio of Fe2+ and tea extract, the solution pH and temperature. Results indicated that the reactivity of Fe NPs increased with higher temperature, but fell with increasing pH and the volume ratio of Fe2+ and tea extract. Scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), Fourier transform infrared spectroscope (FTIR) and X-ray diffraction (XRD) indicated that Fe NPs were spherical in shape, their diameter was 70-80 nm and they were mainly composed of iron oxide nanoparticles. UV-visible (UV-vis) indicated that reactivity of Fe NPs used in degradation of MG significantly depended on the synthesized conditions of Fe NPs. This was due to their impact on the reactivity and morphology of Fe NPs. Finally, degradation of MG showed that 90.56% of MG was removed using Fe NPs.

  17. Green synthesized conditions impacting on the reactivity of Fe NPs for the degradation of malachite green.

    PubMed

    Huang, Lanlan; Luo, Fang; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2015-02-25

    This study investigates green tea extract synthesized conditions impacting on the reactivity of iron nanoparticles (Fe NPs) used for the degradation of malachite green (MG), including the volume ratio of Fe(2+) and tea extract, the solution pH and temperature. Results indicated that the reactivity of Fe NPs increased with higher temperature, but fell with increasing pH and the volume ratio of Fe(2+) and tea extract. Scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), Fourier transform infrared spectroscope (FTIR) and X-ray diffraction (XRD) indicated that Fe NPs were spherical in shape, their diameter was 70-80 nm and they were mainly composed of iron oxide nanoparticles. UV-visible (UV-vis) indicated that reactivity of Fe NPs used in degradation of MG significantly depended on the synthesized conditions of Fe NPs. This was due to their impact on the reactivity and morphology of Fe NPs. Finally, degradation of MG showed that 90.56% of MG was removed using Fe NPs.

  18. Malachite green adsorption onto natural zeolite and reuse by microwave irradiation.

    PubMed

    Han, Runping; Wang, Yu; Sun, Qing; Wang, Lulu; Song, Jiyun; He, Xiaotian; Dou, Chanchan

    2010-03-15

    Natural zeolite was used for the removal of malachite green (MG) from aqueous solution in batch mode and reused by microwave irradiation. The isotherm data were analyzed by the Langmuir, Freundlich, Redlich-Peterson, and Koble-Corrigan isotherm model. The better fit for the equilibrium process was Koble-Corrigan model. The kinetic studies indicated that the adsorption followed the pseudo-second-order kinetic. Thermodynamic calculations showed that the adsorption was spontaneous and endothermic process. Spent zeolite was treated by microwave irradiation and it was found that yield of regeneration was 85.8% in the case of microwave irradiated time 10 min at 160 W.

  19. Graphene oxide caged in cellulose microbeads for removal of malachite green dye from aqueous solution.

    PubMed

    Zhang, Xiaomei; Yu, Hongwen; Yang, Hongjun; Wan, Yuchun; Hu, Hong; Zhai, Zhuang; Qin, Jieming

    2015-01-01

    A simple sol-gel method using non-toxic and cost-effective precursors has been developed to prepare graphene oxide (GO)/cellulose bead (GOCB) composites for removal of dye pollutants. Taking advantage of the combined benefits of GO and cellulose, the prepared GOCB composites exhibit excellent removal efficiency towards malachite green (>96%) and can be reused for over 5 times through simple filtration method. The high-decontamination performance of the GOCB system is strongly dependent on encapsulation amount of GO, temperature and pH value. In addition, the adsorption behavior of this new adsorbent fits well with the Langmuir isotherm and pseudo-second-order kinetic model.

  20. Pathway and Molecular Mechanisms for Malachite Green Biodegradation in Exiguobacterium sp. MG2

    PubMed Central

    Wang, Ji’ai; Gao, Feng; Liu, Zhongzhong; Qiao, Min; Niu, Xuemei; Zhang, Ke-Qin; Huang, Xiaowei

    2012-01-01

    Malachite green (MG), N-methylated diaminotriphenylmethane, is one of the most common dyes in textile industry and has also been used as an effective antifungal agent. However, due to its negative impact on the environment and carcinogenic effects to mammalian cells, there is a significant interest in developing microbial agents to degrade this type of recalcitrant molecules. Here, an Exiguobacterium sp. MG2 was isolated from a river in Yunnan Province of China as one of the best malachite green degraders. This strain had a high decolorization capability even at the concentration of 2500 mg/l and maintained its stable activity within the pH range from 5.0 to 9.0. High-pressure liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography–mass spectrometry were employed to detect the catabolic pathway of MG. Six intermediate products were identified and a potential biodegradation pathway was proposed. This pathway involves a series of reactions of N-demethylation, reduction, benzene ring-removal, and oxidation, which eventually converted N-methylated diaminotriphenylmethane into N, N-dimethylaniline that is the key precursor to MG. Furthermore, our molecular biology experiments suggested that both triphenylmethane reductase gene tmr and cytochrome P450 participated in MG degradation, consistent with their roles in the proposed pathway. Collectively, our investigation is the first report on a biodegradation pathway of triphenylmethane dye MG in bacteria. PMID:23251629

  1. Investigation on removal of malachite green using EM based compost as adsorbent.

    PubMed

    Bhagavathi Pushpa, T; Vijayaraghavan, J; Sardhar Basha, S J; Sekaran, V; Vijayaraghavan, K; Jegan, J

    2015-08-01

    The discarded materials from different sources can be utilized as effective materials in wastewater remediation. This proposed study was aimed mainly to investigate the possibility of Effective Microorganisms based compost (EMKC), which is derived from the kitchen solid waste, as a non-conventional low cost adsorbent for the removal of malachite green from aqueous solution. Batch experiments were carried out to evaluate the optimum operating parameters like pH (2-9), initial dye concentration (50-1000mg/L), adsorbent particle size (0.6-2.36mm) and adsorbent dosage (2-12g/L). EMKC recorded maximum uptake of 136.6mg/g of MG at pH 8, initial dye concentration 1000mg/L, adsorbent particle size 1.18mm and adsorbent dosage 4g/L. Two and three parameter adsorption models were employed to describe experimental biosorption isotherm data. The results revealed that the Sips model resulted in better fit than other models. The pseudo-first and -second order models were applied to describe kinetic data, of which the pseudo-second order described experimental data better with high correlation coefficient. This investigation suggested that EMKC could be an effective and low cost material for the removal of malachite green dye from aqueous solution.

  2. Nanobeads-based rapid magnetic solid phase extraction of trace amounts of leuco-malachite green in Chinese major carps.

    PubMed

    Guo, Liang; Zhang, Jianwen; Wei, Hua; Lai, Weihua; Aguilar, Zoraida P; Xu, Hengyi; Xiong, Yonghua

    2012-08-15

    A proof-of-concept for the use of oleic acid coated magnetic nanobeads (OA-MNBs) for the magnetic solid phase extraction (MSPE) of trace amounts of leuco-malachite green (LMG) from fish samples was developed. The OA-MNBs were prepared by covalently conjugating oleic acid on amino-modified magnetic polystyrene beads. The OA-MNBs were characterized with transmission electron microscopy, Fourier transform infrared spectroscopy and zeta-potential analyzer. The optimized parameters for MSPE with OA-MNBs of LMG from fish muscle involved a combination of pH 10.0 in 10% acetonitrile, 1.5 M sodium chloride as an adsorption solution, and an extraction procedure involving 6 mg OA-MNBs in 18 mL LMG adsorption solution. This was optimized for 0.5 g fish muscles with an incubation period of 10 min using 200 μL acetonitrile for elution. Using the optimized parameters, the performance of MSPE with OA-MNBs was evaluated by analyzing LMG-spiked fish extracts with liquid chromatography-mass spectrometry (LC-MS/MS) method. The results indicated that recoveries of LMG (from 0.1 to 2 ng/g) ranged from 71.2%-112.6% with relative standard deviations as low as 0.6%. Out of 57 field fish samples, eight LMG positive samples were confirmed using MSPE with OA-MNBs. Compared with traditional liquid-liquid extraction methods, the results showed that MSPE with OA-MNBs had a higher sensitivity for samples with low LMG concentration. Furthermore, the MSPE with OA-MNB took only 40 min to perform without the need for time consuming sample-pretreatment process. Therefore, MSPE with OA-MNBs holds promise for rapid, sensitive, and cost effective screening for LMG in fish samples.

  3. Synthesis of iron-based nanoparticles using oolong tea extract for the degradation of malachite green

    NASA Astrophysics Data System (ADS)

    Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-01-01

    Iron-based nanoparticles (OT-FeNP) were synthesized using oolong tea extracts. Their morphology, structure and size were confirmed by scanning electron microscopy (SEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), UV-visible (UV-vis) and Fourier Transform Infrared spectroscopy (FTIR). Formation of FeNP results in mostly spherical particles with diameters ranging from 40 to 50 nm. Degradation of malachite green (MG) using OT-FeNP demonstrated that kinetics fitted well to the pseudo first-order reaction by removing 75.5% of MG (50 mg/L). This indicated that OT-FeNP has the potential to serve as a green nanomaterial for environmental remediation.

  4. Kinetics and equilibrium studies of malachite green adsorption on rice straw-derived char.

    PubMed

    Hameed, B H; El-Khaiary, M I

    2008-05-01

    In this work, the potential feasibility of rice straw-derived char (RSC) for removal of C.I. Basic Green 4 (malachite green (MG)), a cationic dye from aqueous solution was investigated. The isotherm parameters were estimated by non-linear regression analysis. The equilibrium process was described well by the Langmuir isotherm model. The maximum RSC sorption capacity was found to be 148.74 mg/L at 30 degrees C. The kinetics of MG sorption on RSC followed the Lagergren's pseudo-first-order model and the overall rate of dye uptake was found to be controlled by external mass transfer at the beginning of adsorption, while intraparticle diffusion controlled the overall rate of adsorption at a later stage. The results indicated that RSC was an attractive adsorbent for removing basic dye from aqueous solutions.

  5. Synthesis of iron-based nanoparticles using oolong tea extract for the degradation of malachite green.

    PubMed

    Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-01-03

    Iron-based nanoparticles (OT-FeNP) were synthesized using oolong tea extracts. Their morphology, structure and size were confirmed by scanning electron microscopy (SEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), UV-visible (UV-vis) and Fourier Transform Infrared spectroscopy (FTIR). Formation of FeNP results in mostly spherical particles with diameters ranging from 40 to 50 nm. Degradation of malachite green (MG) using OT-FeNP demonstrated that kinetics fitted well to the pseudo first-order reaction by removing 75.5% of MG (50 mg/L). This indicated that OT-FeNP has the potential to serve as a green nanomaterial for environmental remediation.

  6. HPLC Determination and MS Confirmation of Malachite Green, Gentian Violet, and Their Leuco Metabolites in Catfish Muscle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in catfish muscle were individually determined by HPLC using visible and fluorescence detectors. This detection scheme obviated a PbO2 column that converts leuco forms to chromatic forms for visible detection, thus el...

  7. Decolorizing activity of malachite green and its mechanisms involved in dye biodegradation by Achromobacter xylosoxidans MG1.

    PubMed

    Wang, Ji'ai; Qiao, Min; Wei, Kangbi; Ding, Junmei; Liu, Zhongzhong; Zhang, Ke-Qin; Huang, Xiaowei

    2011-01-01

    An Achromobacter xylosoxidans MG1 strainisolated from the effluent treatment plant of a textile and dyeing factory from Yunnan Province in China was found capable of decolorizing the malachite green dye at a high efficacy. Strain MG1 reduced 86% malachite green at the concentration of 2,000 mg/l within 1 h, representing a greater ability for decolorizing and a higher tolerance of this compound than all previously reported bacteria. Color removal was optimal at pH 6 and 38°C. Further experimental evidences demonstrated that both cytoplasmic and extracellular biodegradation contributed to the decolorization of malachite green. Nested PCR was employed to identify the candidate genes responsible for malachite green decolorization, and we identified a cytoplasmic triphenylmethane reductase gene with 100% amino acid similarity to the corresponding gene in Citrobacter sp. strain. In contrast to our expectation, the addition of metyrapone had little effect on the cytoplasmic biodegradation, suggesting that cytochrome P450 was not involved in the high-performance reduction. The extracellular biodegradation was likely attributable to the secretion of extracellular proteases and some heat-resistant compounds.

  8. Malachite green toxicity assessed on Asian catfish primary cultures of peripheral blood mononuclear cells by a proteomic analysis.

    PubMed

    Pierrard, Marie-Aline; Kestemont, Patrick; Delaive, Edouard; Dieu, Marc; Raes, Martine; Silvestre, Frédéric

    2012-06-15

    The potential genotoxic and carcinogenic properties reported for malachite green (MG) and the frequent detection of MG residues in fish and fish products, despite the ban of MG, have recently generated great concern. Additional toxicological data are required for a better understanding of the mechanism of action and a more comprehensive risk assessment for the exposure of fish to this fungicide. To date, the use of fish peripheral blood mononuclear cells (PBMCs) has not been exploited as a tool in the assessment of the toxicity of chemicals. However, PBMCs are exposed to toxicants and can be easily collected by blood sampling. The present study aims at better understanding the effects of MG by a proteomic analysis of primary cultured PBMC from the Asian catfish, Pangasianodon hypophthalmus, exposed to MG. The two lowest concentrations of 1 and 10 ppb were selected based on the MTS (water soluble tetrazolium salts) cytotoxicity test. Using a proteomic analysis (2D-DIGE), we showed that 109 proteins displayed significant changes in abundance in PBMC exposed during 48 h to MG. Most of these proteins were successfully identified by nano LC-MS/MS and validated through the Peptide and Protein Prophet of Scaffold™ software, but only 19 different proteins were considered corresponding to a single identification per spot. Our data suggest that low concentrations of MG could affect the mitochondrial metabolic functions, impair some signal transduction cascades and normal cell division, stimulate DNA repair and disorganize the cytoskeleton. Altogether, these results confirm that the mitochondrion is a target of MG toxicity. Further studies on the identified proteins are needed to better understand the mechanisms of MG toxicity in fish produced for human consumption.

  9. The effect of toxic malachite green on the bacterial community in Antarctic soil and the physiology of malachite green-degrading Pseudomonas sp. MGO.

    PubMed

    Jung, Jaejoon; Seo, Hyoju; Lee, Se Hee; Jeon, Che Ok; Park, Woojun

    2013-05-01

    The effects of malachite green (MG) on the bacterial community in Antarctic soil were assessed. Culture-independent community analysis using 16S rRNA gene pyrosequencing showed that, in the presence of MG, the relative abundance of Pseudomonas dramatically increased from 2.2 % to 36.6 % (16.6-fold), and Pseudomonas became the predominant genus. The reduction in bacterial biodiversity was demonstrated by diversity indices and rarefaction curves. MG-degrading Pseudomonas sp. MGO was isolated from Antarctic soil. MG tolerance and decolorization activity were confirmed by growth, spectrophotometric, high-performance liquid chromatography, and thin-layer chromatography analyses in high MG concentrations. Our data showed that the decolorization process occurred via biodegradation, while biosorption also occurred after some time during the fed-batch decolorization process. Significant inductions in laccase, nicotinamide adenine dinucleotide-2,6 dichlorophenol indophenol reductase, and MG reductase activities suggested their involvement in the decolorization process. We also showed that the high tolerance of strain MGO to toxic MG might be mediated by upregulation of oxidative stress defense systems such as superoxide dismutase and protease. Collectively, these results demonstrated the response of the Antarctic soil bacterial community to MG and provided insight into the molecular mechanism of MG-tolerant Pseudomonas strains isolated from Antarctic soil.

  10. Function and dynamics of aptamers: A case study on the malachite green aptamer

    SciTech Connect

    Wang, Tianjiao

    2008-01-01

    Aptamers are short single-stranded nucleic acids that can bind to their targets with high specificity and high affinity. To study aptamer function and dynamics, the malachite green aptamer was chosen as a model. Malachite green (MG) bleaching, in which an OH- attacks the central carbon (C1) of MG, was inhibited in the presence of the malachite green aptamer (MGA). The inhibition of MG bleaching by MGA could be reversed by an antisense oligonucleotide (AS) complementary to the MGA binding pocket. Computational cavity analysis of the NMR structure of the MGA-MG complex predicted that the OH- is sterically excluded from the C1 of MG. The prediction was confirmed experimentally using variants of the MGA with changes in the MG binding pocket. This work shows that molecular reactivity can be reversibly regulated by an aptamer-AS pair based on steric hindrance. In addition to demonstrate that aptamers could control molecular reactivity, aptamer dynamics was studied with a strategy combining molecular dynamics (MD) simulation and experimental verification. MD simulation predicted that the MG binding pocket of the MGA is largely pre-organized and that binding of MG involves reorganization of the pocket and a simultaneous twisting of the MGA terminal stems around the pocket. MD simulation also provided a 3D-structure model of unoccupied MGA that has not yet been obtained by biophysical measurements. These predictions were consistent with biochemical and biophysical measurements of the MGA-MG interaction including RNase I footprinting, melting curves, thermodynamic and kinetic constants measurement. This work shows that MD simulation can be used to extend our understanding of the dynamics of aptamer-target interaction which is not evident from static 3D-structures. To conclude, I have developed a novel concept to control molecular reactivity by an aptamer based on steric protection and a strategy to study the dynamics of aptamer-target interaction by combining MD

  11. High accuracy determination of malachite green and leucomalachite green in salmon tissue by exact matching isotope dilution mass spectrometry.

    PubMed

    Hall, Zoe; Hopley, Chris; O'Connor, Gavin

    2008-10-15

    A high accuracy method for the quantification of malachite green (MG) and leucomalachite green (LMG) in salmon is described. Analytical challenges including the effects of analyte instability and matrix suppression were minimised by the use of exact matching isotope dilution mass spectrometry. The developed method included overnight extraction in acidified acetonitrile/ammonium acetate buffer and analysis by LC-MS/MS utilising isotopic internal standards. This method was used to determine the level of MG and LMG in a sample of salmon used in an international inter-comparison organised by the Comité Consultatif pour la Quantité de Matière (CCQM). The sum of MG and LMG was found to be 9.32+/-0.98ngg(-1) at the 95% confidence interval (relative expanded uncertainty 10.5% (k=2)). This encompassed the mean and median of the CCQM inter-comparison.

  12. Study of malachite green adsorption by organically modified clay using a batch method

    NASA Astrophysics Data System (ADS)

    Arellano-Cárdenas, Sofía; López-Cortez, Socorro; Cornejo-Mazón, Maribel; Mares-Gutiérrez, Juan Carlos

    2013-09-01

    The adsorption of toxic dye malachite green from aqueous effluents by organically modified clay was studied in a batch system. The organoclay (OC) used was prepared by the intercalation of cationic surfactant hexadecyltrimethylammonium bromide in a Mexican montmorillonite. The effects of initial dye concentration, temperature, pH, and contact time were investigated. The OC showed a high dye removal (99.6%) from an initial dye concentration of 60 mg L-1 at pH 6 and 25 °C. The adsorption capacity was independent of pH and increased with the temperature. Equilibrium data were well fitted by Langmuir adsorption model. The rate of sorption was adjusted to a pseudo second-order kinetic model.

  13. Use of Enzymatic Bio-Fenton as a New Approach in Decolorization of Malachite Green

    PubMed Central

    Karimi, Afzal; Aghbolaghy, Mostafa; Khataee, Alireza; Shoa Bargh, Shabnam

    2012-01-01

    An enzymatic reaction using glucose oxidase was applied for in situ production of hydrogen peroxide for use in simultaneously Fenton's reaction in decolorization of malachite green. It was found that decolorization rate increased by increasing of glucose concentration from 0.2 g/L to 1.5 g/L. Decolorization rate showed different behaviors versus temperature changes. Initial rate of decolorization process was increased by increasing of temperature; after 30 minutes, especially at temperatures above 30°C, the decolorization rate was gradually reduced. The pH value in the reaction media was decreased from natural to about pH = 3 which had synergic effect on the Fenton process by stabilizing of Fe2+ ions. PMID:22649310

  14. Fast and sensitive trace analysis of malachite green using a surface-enhanced Raman microfluidic sensor.

    PubMed

    Lee, Sangyeop; Choi, Junghyun; Chen, Lingxin; Park, Byungchoon; Kyong, Jin Burm; Seong, Gi Hun; Choo, Jaebum; Lee, Yeonjung; Shin, Kyung-Hoon; Lee, Eun Kyu; Joo, Sang-Woo; Lee, Kyeong-Hee

    2007-05-08

    A rapid and highly sensitive trace analysis technique for determining malachite green (MG) in a polydimethylsiloxane (PDMS) microfluidic sensor was investigated using surface-enhanced Raman spectroscopy (SERS). A zigzag-shaped PDMS microfluidic channel was fabricated for efficient mixing between MG analytes and aggregated silver colloids. Under the optimal condition of flow velocity, MG molecules were effectively adsorbed onto silver nanoparticles while flowing along the upper and lower zigzag-shaped PDMS channel. A quantitative analysis of MG was performed based on the measured peak height at 1615 cm(-1) in its SERS spectrum. The limit of detection, using the SERS microfluidic sensor, was found to be below the 1-2 ppb level and this low detection limit is comparable to the result of the LC-Mass detection method. In the present study, we introduce a new conceptual detection technology, using a SERS microfluidic sensor, for the highly sensitive trace analysis of MG in water.

  15. Entropy and Mg2+ control ligand affinity and specificity in the malachite green binding RNA aptamer.

    PubMed

    Bernard Da Costa, Jason; Dieckmann, Thorsten

    2011-07-01

    The binding of small molecule targets by RNA aptamers provides an excellent model to study the versatility of RNA function. The malachite green aptamer binds and recognizes its ligand via stacking and electrostatic interactions. The binding of the aptamer to its original selection target and three related molecules was determined by isothermal titration calorimetry, equilibrium dialysis, and fluorescence titration. The results reveal that the entropy of complex formation plays a large role in determining binding affinity and ligand specificity. These data combined with previous structural studies show that metal ions are required to stabilize the complexes with non-native ligands whereas the complex with the original selection target is stable at low salt and in the absence of divalent metal ions.

  16. Extraction-spectrophotometric determination of germanium(IV) with mandelic acid and malachite green.

    PubMed

    Sato, S; Tanaka, H

    1989-03-01

    A method has been developed for determination of germanium, based on complexation with mandelic acid and extraction of the ion-associate formed with Malachite Green (MG) into chlorobenzene. A weakly acidic aqueous solution (pH 2.5-3.5) at room temperature is used and indirect determination is achieved by measuring the absorbance of MG in the extract, at 628 mn. The calibration graph is linear over the range (0.17-8.63) x 10(-6) (0.05-2.50 mug of germanium); the apparent molar absorptivity is 1.33 x 10(5) 1.mole(-1).cm(-1). The interferences from Fe, Ti, Sn(IV), Mo, and SB(III) can be eliminated by addition of trans-1,2-diaminocyclohexanetetra-acetic acid and sodium diethyldithiocarbamate.

  17. Thermodynamics and kinetics of adaptive binding in the malachite green RNA aptamer.

    PubMed

    Da Costa, Jason B; Andreiev, Aurelia I; Dieckmann, Thorsten

    2013-09-24

    Adaptive binding, the ability of molecules to fold themselves around the structure of a ligand and thereby incorporating it into their three-dimensional fold, is a key feature of most RNA aptamers. The malachite green aptamer (MGA) has been shown to bind several closely related triphenyl dyes with planar and nonplanar structures in this manner. Competitive binding studies using isothermal titration calorimetry and stopped flow kinetics have been conducted with the aim of understanding the adaptive nature of RNA-ligand interaction. The results of these studies reveal that binding of one ligand can reduce the ability of the aptamer pocket to adapt to another ligand, even if this second ligand has a significantly higher affinity to the free aptamer. A similar effect is observed in the presence of Mg(2+) ions which stabilize the binding pocket in a more ligand bound-like conformation.

  18. Determination of trace amount of formaldehyde base on a bromate-Malachite Green system

    NASA Astrophysics Data System (ADS)

    Tang, Yufang; Chen, Hao; Weng, Chao; Tang, Xiaohui; Zhang, Miaoling; Hu, Tao

    2015-01-01

    A novel catalytic kinetic spectrophotometric method for determination of trace amount of formaldehyde (FA) has been established, based on catalytic effect of trace amount of FA on the oxidation of Malachite Green (MG) by potassium bromate in presence of sulfuric acid medium, and was reported for the first time. The method was monitored by measuring the decrease in absorbance of MG at 617 nm and allowed a precise determination of FA in the range of 0.003-0.08 μg mL-1, with a limit of detection down to 1 ng mL-1. The relative standard deviation of 10 replicate measurements was 1.63%. The method developed was approved to be sensitive, selective and accurate, and adopted to determinate free FA in samples directly with good accuracy and reproducibility.

  19. Colorimetric determination of low pH with malachite green. Revision 1

    SciTech Connect

    Cloessner, P.F.; Baumann, E.W.

    1994-04-01

    A spectrophotometric method was developed for determination of concentration-based pH values from 0 to 2 with malachite green indicator. A quadratic model equation was based on the ratio of the absorbances of the peak at 618 nm and the isosbestic point at 518 nm. Normalization to the isosbestic point was used to stabilize the response because the color faded; the useful time interval was within 5 minutes after indicator addition. Model and verification sets agreed within {plus_minus}0.02 pH units between pH 0.3 and 1.8. This excellent precision makes the colorimetric method useful for acid determinations with a relative precision of >{plus_minus}5%. The presence of salts at a salt/acid equivalent ratio >0.l caused a low pH bias.

  20. Quest for the binding mode of malachite green with humic acid

    NASA Astrophysics Data System (ADS)

    Zhang, Hongmei; Yin, Mingxing; Shi, Jinghua; Wang, Yanqing

    2015-02-01

    The association of malachite green (MG) with humic acid (HA) was investigated by using fluorescence, UV-vis spectroscopy and molecular Modelling method. The fluorescence spectral results indicated that the binding between MG and HA occurred by mainly hydrophobic and electrostatic forces with association constants of KA (298 K) = 6.24 × 105 L/mol and KA (310 K) = 10.20 × 105 L/mol. There were more than one binding sites on HA to bind with MG. The binding sites of MG with HA primarily located at the aromatic rings of HA. MG could enter into the hydrophobic cavities of HA to quench the fluorescence of HA. On the contrary, HA binding caused MG to a coplanar conformation with more extended π bond distribution by π-π stacking interactions. The experiment and calculation data both showed that the hydrophobic binding cavities in HA played a key role in its binding with MG.

  1. Biosorption of malachite green by eggshells: mechanism identification and process optimization.

    PubMed

    Podstawczyk, Daria; Witek-Krowiak, Anna; Chojnacka, Katarzyna; Sadowski, Zygmunt

    2014-05-01

    In the present work, eggshells were used to remove a dye (malachite green) from wastewater. The study was focused on identification and describing the binding mechanism of the dye by eggshells in a biosorption process optimized by Response Surface Methodology based on the Box-Behnken Design. The mechanism of biosorption was determined by characterization of the biosorbent before and after biosorption using scanning electron microscopy, X-ray diffraction analysis, the Brunauer-Emmett-Teller isotherm method, Fourier transform infrared spectroscopy. The second-order polynomial equation and 3D response surface plots were used to quantitatively determine the relationships between dependent and independent variables. The obtained results suggested the mechanism of wastewater treatment that included physical adsorption, alkaline fading phenomenon and microprecipitation. The results of the present study showed that waste eggshells have the potential to be used as an inexpensive but effective biosorbent useful in wastewater treatment.

  2. Determination of trace amount of formaldehyde base on a bromate-Malachite Green system.

    PubMed

    Tang, Yufang; Chen, Hao; Weng, Chao; Tang, Xiaohui; Zhang, Miaoling; Hu, Tao

    2015-01-25

    A novel catalytic kinetic spectrophotometric method for determination of trace amount of formaldehyde (FA) has been established, based on catalytic effect of trace amount of FA on the oxidation of Malachite Green (MG) by potassium bromate in presence of sulfuric acid medium, and was reported for the first time. The method was monitored by measuring the decrease in absorbance of MG at 617 nm and allowed a precise determination of FA in the range of 0.003-0.08 μg mL(-1), with a limit of detection down to 1 ng mL(-1). The relative standard deviation of 10 replicate measurements was 1.63%. The method developed was approved to be sensitive, selective and accurate, and adopted to determinate free FA in samples directly with good accuracy and reproducibility.

  3. Malachite green decolorization by the filamentous fungus Myrothecium roridum--Mechanistic study and process optimization.

    PubMed

    Jasińska, Anna; Paraszkiewicz, Katarzyna; Sip, Anna; Długoński, Jerzy

    2015-10-01

    The filamentous fungus Myrothecium roridum isolated from a dye-contaminated area was investigated in terms of its use for the treatment of Malachite green (MG). The mechanisms involved in this process were established. Peroxidases and cytochrome P-450 do not mediate MG elimination. The laccase of M. roridum IM 6482 was found to be responsible for the decolorization of 8-11% of MG. Thermostable low-molecular-weight factors (LMWF) resistant to sodium azide were found to be largely involved in dye decomposition. In addition, MG decolorization by M. roridum IM 6482 occurred in a non-toxic manner. Data from antimicrobial tests showed that MG toxicity decreased after decolorization. To optimize the MG decolorization process, the effects of operational parameters (such as the medium pH and composition, process temperature and culture agitation) were examined. The results demonstrate that M. roridum IM 6482 may be used effectively as an alternative to traditional decolorization agents.

  4. Adsorption and photocatalytic degradation of malachite green by vanadium doped zinc oxide nanoparticles.

    PubMed

    Khezami, L; Taha, Kamal K; Ghiloufi, Imed; El Mir, Lassaad

    2016-01-01

    Herein the degradation of malachite green (MG) dye from aqueous medium by vanadium doped zinc oxide (ZnO:V3%) nanopowder was investigated. The specific surface area and pore volume of the nanopowder was characterized by nitrogen adsorption method. Batch experimental procedures were conducted to investigate the adsorption and photocatalytic degradation of MG dye. Adsorption kinetics investigations were performed by varying the amount of the catalyst and the initial dye concentrations. Adsorption and photocatalytic degradation data were modeled using the Lagergren pseudo-first-order and second-order kinetic equation. The results showed that the ZnO:V3% nanopowder was particularly effective for the removal of MG and data were found to comply with Lagergreen pseudo-first-order kinetic model.

  5. Malachite green "a cationic dye" and its removal from aqueous solution by adsorption

    NASA Astrophysics Data System (ADS)

    Raval, Nirav P.; Shah, Prapti U.; Shah, Nisha K.

    2016-12-01

    Adsorption can be efficiently employed for the removal of various toxic dyes from water and wastewater. In this article, the authors reviewed variety of adsorbents used by various researchers for the removal of malachite green (MG) dye from an aqueous environment. The main motto of this review article was to assemble the scattered available information of adsorbents used for the removal of MG to enlighten their wide potential. In addition to this, various optimal experimental conditions (solution pH, equilibrium contact time, amount of adsorbent and temperature) as well as adsorption isotherms, kinetics and thermodynamics data of different adsorbents towards MG were also analyzed and tabulated. Finally, it was concluded that the agricultural solid wastes and biosorbents such as biopolymers and biomass adsorbents have demonstrated outstanding adsorption capabilities for removal of MG dye.

  6. NTP technical report on the toxicity studies of malachite green chloride and leucomalachite green (CAS Nos. 569-64-2 and 129-73-7) administered in feed to F344/N rats and B6C3F1 mice.

    PubMed

    Culp, Sandra J

    2004-06-01

    Malachite green chloride is a triphenylmethane dye used in the fish and dye industries. Leucomalachite green is prepared by the reduction of malachite green chloride. Malachite green chloride was nominated for toxicity and carcinogenicity testing by the Food and Drug Administration and selected by the National Institutes of Environmental Health Sciences for carcinogenicity testing by the National Toxicology Program (NTP) due to the potential for significant worker and consumer exposure and lack of carcinogenicity data. The current 28-day studies were conducted as part of an overall effort by the NTP to determine the toxicity and carcinogenicity of malachite green chloride. Male and female F344/N Nctr BR rats and B6C3F1/Nctr BR (C57BL/6N x C3H/HeN MTV-) mice were exposed to malachite green chloride (95% pure) or leucomalachite green (99% pure) (male rats and female mice only) in feed for 28 days. Animals were evaluated for clinical pathology and histopathology. Genetic toxicity studies formalachite green chloride were conducted in vitro in Salmonella typhimurium and in vivo in rat bone marrow erythrocytes and in mouse peripheral blood erythrocytes. Genetic toxicity studies for leucomalachite green were conducted in vivo in mouse peripheral blood erythrocytes. Groups of eight male and eight female rats and mice were fed diets containing 0, 25, 100, 300, 600, or 1,200 ppm malachite green chloride for 28 days. Additional groups of eight male and eight female rats designated for thyroid hormone assays were fed diets containing 0 or 1,200 ppm malachite green chloride. Groups of eight male rats and eight female mice were fed diets containing 0, 290, 580, or 1,160 ppm leucomalachite green for 28 days. Additional groups of eight male rats designated for thyroid hormone assays were fed diets containing 0 or 1,160 ppm leucomalachite green. All rats and mice survived to the end of the studies. In the malachite green chloride study, the body weight gain of males rats in the 1

  7. Surface-hopping dynamics simulations of malachite green: a triphenylmethane dye.

    PubMed

    Xie, Bin-Bin; Xia, Shu-Hua; Liu, Li-Hong; Cui, Ganglong

    2015-06-04

    Malachite green is a typical triphenylmethane dye widely used in fundamental and industrial research; however, its excited-state relaxation dynamics remains elusive. In this work we simulate its photodynamics from the S2 and S1 states using the fewest-switches surface-hopping scheme. In the S2 photodynamics, the system first relaxes to the S2 minimum, which immediately hops to the S1 state via an S2/S1 conical intersection. In the S1 state, 90% trajectories evolve into a structurally symmetric S1 minimum; the remaining ones proceed toward two propeller-like S1 minima. Two kinds of S1 minima then decay to the S0 state via the S1/S0 conical intersections. The S1 photodynamics is overall similar to the S1 excited-state dynamics as a result of the ultrafast S2 → S1 internal conversion in the S2 photodynamics, but the weights of the trajectories that decay to the S0 state via three different S1/S0 conical intersections are variational. Moreover, the S2 relaxation dynamics mainly happens in a concerted synchronous rotation of three phenyl rings. In comparison, in the S1 relaxation dynamics, the rotations of two aminophenyl rings can proceed in the same and opposite directions. In certain trajectories, only the rotation of an aminophenyl ring is active. On the basis of the results, the S2 and S1 excited-state lifetimes of malachite green in vacuo are calculated to be 424 fs and 1.2 ps, respectively. The present work provides important mechanistic insights for similar triphenylmethane dyes.

  8. Thermodynamics of Ligand Binding to a Heterogeneous RNA Population in the Malachite Green Aptamer

    PubMed Central

    Sokoloski, Joshua E.; Dombrowski, Sarah E.; Bevilacqua, Philip C.

    2011-01-01

    The malachite green aptamer binds two closely related ligands, malachite green (MG) and tetramethylrosamine (TMR), with near equal affinity. The MG ligand consists of three phenyl rings emanating from a central carbon, while TMR has two of the three rings connected by an ether linkage. The binding pockets for MG and TMR in the aptamer, known from high-resolution structure, differ only in the conformation of a few nucleotides. Herein, we applied isothermal titration calorimetry (ITC) to compare the thermodynamics for binding of MG and TMR to the aptamer. Binding heat capacities were obtained from ITC titrations over the temperature range of 15 to 60 °C. Two temperature regimes were found for MG binding: one from 15 to 45 °C where MG bound with a large negative heat capacity and an apparent stoichiometry (n) of ~0.4, and another from 50 to 60 °C where MG bound with positive heat capacity and n~1.1. The binding of TMR, on the other hand, revealed only one temperature regime for binding, with a more modest negative heat capacity and n~1.2. The large difference in heat capacity between the two ligands suggests that significantly more conformational rearrangement occurs upon the binding of MG than TMR, which is consistent with differences in solvent accessible surface area calculated for available ligand-bound structures. Lastly, we note that binding stoichiometry of MG was improved not only by raising the temperature, but also by lowering the concentration of Mg2+ or increasing the time between ITC injections. These studies suggest that binding of a dynamical ligand to a functional RNA requires the RNA itself to have significant dynamics. PMID:22192051

  9. Analysis of malachite green in aquatic products by carbon nanotube-based molecularly imprinted - matrix solid phase dispersion.

    PubMed

    Wang, Yu; Chen, Ligang

    2015-10-01

    A simple method based on matrix solid phase dispersion (MSPD) using molecularly imprinted polymers (MIPs) as sorbents for selective extraction of malachite green (MG) from aquatic products was developed. The MIPs were prepared by using carbon nanotube as support, MG as template, methacrylic acid as functional monomer, ethyleneglycol dimethacrylate as crosslinker and methylene chloride as solvent. The MIPs were characterized by Fourier transform infrared spectrometry and transmission electron microscopy. The isothermal adsorption, kinetics absorption and selective adsorption experiments were carried out. We optimized the extraction conditions as follows: the ratio of MIPs to sample was 2:3, the dispersion time was 15min, washing solvent was 4mL 50% aqueous methanol and elution solvent was 3mL methanol-acetic acid (98: 2, v/v). Once the MSPD process was completed, the MG extracted from aquatic products was determined by high performance liquid chromatography. The detection limit of MG was 0.7μgkg(-1). The relative standard deviations of intra-day and inter-day were obtained in the range of 0.9%-4.7% and 3.4%-9.8%, respectively. In order to evaluate the applicability and reliability of the proposed method, it was applied to determine MG in different aquatic products samples including fish, shrimp, squid and crabs. The satisfied recoveries were in the range of 89.2%-104.6%. The results showed that this method is faster, simpler and makes extraction and purification in the same system.

  10. Establishment of a transgenic yeast screening system for estrogenicity and identification of the anti-estrogenic activity of malachite green.

    PubMed

    Jiao, Baowei; Yeung, Eric K C; Chan, Chi Bun; Cheng, Christopher H K

    2008-12-15

    Endocrine disruptors refer to chemical compounds in the environment which interfere with the endocrine systems of organisms. Among them, environmental estrogens pose serious problems to aquatic organisms, in particular fish. It is therefore important and necessary to have a fast and low-cost system to screen the large number of different chemical compounds in the aquatic environment for their potential endocrine disrupting actions. In this study, a screening platform was developed to detect xenoestrogens in the aquatic environment using the fission yeast Schizosaccharomyces pombe, and applied for compound screening. The aim was to demonstrate any significant potential differences between the fish screening system and the human screening system. To this end, a yeast expression vector harboring a fish estrogen receptor alpha and a reporter vector containing the estrogen responsive element fused with the Escherichia coli LacZ gene were constructed. After transformation with these two vectors, the transformed yeast clones were confirmed by Western blotting and selected on the basis of the beta-galactosidase activity. In this transgenic yeast system, the natural estrogen (estradiol) and other known xenoestrogens such as diethylstilbestrol, bisphenol A, genistein and dichloro-diphenyl-trichloroethane exhibited dose-dependent activities. Using this system, more than 40 putative endocrine disruptors including phytoestrogens, pesticides, herbicides, industrial dyes and other industrial chemicals were screened. Ten of them were demonstrated to exhibit estrogenic actions. Industrial dyes such as malachite green (MG) that disrupt thyroid hormone synthesis are extensively used and are widely distributed in the aquatic environment. Using this system, MG did not show any estrogenic action, but was demonstrated to exhibit anti-estrogenic activity.

  11. Exploring redox-mediating characteristics of textile dye-bearing microbial fuel cells: thionin and malachite green.

    PubMed

    Chen, Bor-Yann; Xu, Bin; Qin, Lian-Jie; Lan, John Chi-Wei; Hsueh, Chung-Chuan

    2014-10-01

    Prior studies indicated that biodecolorized intermediates of azo dyes could act as electron shuttles to stimulate wastewater decolorization and bioelectricity generation (WD&BG) in microbial fuel cells (MFCs). This study tended to explore whether non-azo textile dyes (i.e., thionin and malachite green) could also own such redox-mediating capabilities for WD&BG. Prior findings mentioned that OH and/or NH2 substitute-containing auxochrome compounds (e.g., 2-aminophenol and 1,2-dihydroxybenzene) could effectively mediate electron transport in MFCs for simultaneous WD&BG. This work clearly suggested that the presence of electron-mediating textile dyes (e.g., thionin and malachite green (MG)) in MFCs is promising to stimulate color removal and bioelectricity generation. That is, using MFCs as operation strategy for wastewater biodecolorization is economically promising in industrial applications due to autocatalytic acceleration of electron-flux for WD&BG in MFCs.

  12. Development of cloud point extraction using pH-sensitive hydrogel for preconcentration and determination of malachite green.

    PubMed

    Bahram, Morteza; Keshvari, Foroogh; Najafi-Moghaddam, Peyman

    2011-08-15

    A novel and sensitive cloud point extraction procedure using pH-sensitive hydrogel was developed for preconcentration and spectrophotometric determination of trace amounts of malachite green (MG). In this extraction method, appropriate amounts of poly(styrene-alt-maleic acid), as a pH-sensitive hydrogel, and HCl were added respectively into the aqueous sample so a cloudy solution was formed. The cloudy phase consists of hydrogel particles distributed entirely into the aqueous phase. Organic or inorganic compounds having the potential to interact with polymer particles (chemical interaction or physical adsorption) could be extracted to cloudy phase. After centrifuging, these particles of hydrogel were sedimented in the bottom of sample tube. The sedimented hydrogel-rich phase was diluted with acetonitrile and its absorbance was measured at 617 nm (λ(max) of malachite green in hydrogel). Central composite design and response surface method were applied to design the experiments and optimize the experimental parameters such as, concentration of hydrogel and HCl, extraction time and salting out effect. Under the optimum conditions, the linear range was 1 × 10(-8)-5 × 10(-7)mol L(-1) malachite green with a correlation coefficient of 0.992. The limit of detection (S/N=3) was 4.1 × 10(-9) mol L(-1). Relative standard deviation (RSD) for 7 replicate determinations of 10(-7) mol L(-1) malachite green was 3.03%. In this work, the concentration factor of 20 was reached. Also the improvement factor of the proposed method was 23. The advantages of this method are simplicity of operation, rapidity and low cost.

  13. Biosorptive removal of malachite green from aqueous solution using chemically modified brown marine alga Sargassum swartzii.

    PubMed

    Jerold, M; Sivasubramanian, V

    2017-02-01

    Sargassum swartzii, marine macro brown alga, showed a high malachite green (MG) biosorption capacity in batch mode of operation. The analytical evidence from Fourier transform infrared spectra confirmed the involvement of amine group in the biosorption of MG and electrostatic interaction type of mechanism was proposed to occur between the amine group of dye and the cationic MG dye solution. Scanning electron micrograph shows the morphological features and the attachment of dye onto the biosorbent. pH edge experiment shows that biosorption capacity was maximum at pH 10. The effect of biosorbent concentration, pH, temperature, adsorption time was studied for the biosorption of MG using S. swartzii. Langmuir, Freundlich and Temkin models were used to describe the isotherm data, of which Langmuir model described the isotherm data with high coefficient of determination R(2) = 0.999. The maximum dye uptake of 111.1 mg/g was reported at pH 10 based on Langmuir model. Kinetics and temperature profiles were evaluated and reported. Desorption study was carried out with 0.1 M HCl. Efforts were also made to continuously treat MG bearing wastewater using up-flow packed column. Investigations proved that S. swartzii is an excellent biosorbent for the sequestration of MG in aqueous media.

  14. Laccase-catalyzed decolorization of malachite green: performance optimization and degradation mechanism.

    PubMed

    Yang, Jie; Yang, Xiaodan; Lin, Yonghui; Ng, Tzi Bun; Lin, Juan; Ye, Xiuyun

    2015-01-01

    Malachite green (MG) was decolorized by laccase (LacA) of white-rot fungus Cerrena sp. with strong decolorizing ability. Decolorization conditions were optimized with response surface methodology. A highly significant quadratic model was developed to investigate MG decolorization with LacA, and the maximum MG decolorization ratio of 91.6% was predicted under the conditions of 2.8 U mL(-1) LacA, 109.9 mg L(-1) MG and decolorization for 172.4 min. Kinetic studies revealed the Km and kcat values of LacA toward MG were 781.9 mM and 9.5 s(-1), respectively. UV-visible spectra confirmed degradation of MG, and the degradation mechanism was explored with liquid chromatography-mass spectrometry (LC-MS) analysis. Based on the LC-MS spectra of degradation products, LacA catalyzed MG degradation via two simultaneous pathways. In addition, the phytotoxicity of MG, in terms of inhibition on seed germination and seedling root elongation of Nicotiana tabacum and Lactuca sativa, was reduced after laccase treatment. These results suggest that laccase of Cerrena was effective in decolorizing MG and promising in bioremediation of wastewater in food and aquaculture industries.

  15. Biodegradation of dye solution containing Malachite Green: optimization of effective parameters using Taguchi method.

    PubMed

    Daneshvar, N; Khataee, A R; Rasoulifard, M H; Pourhassan, M

    2007-05-08

    In this paper, optimization of biological decolorization of synthetic dye solution containing Malachite Green was investigated. The effect of temperature, initial pH of the solution, type of algae, dye concentration and time of the reaction was studied and optimized using Taguchi method. Sixteen experiments were required to study the effect of parameters on biodegradation of the dye. Each of experiments was repeated three times to calculate signal/noise (S/N). Our results showed that initial pH of the solution was the most effective parameter in comparison with others and the basic pH was favorable. In this study, we also optimized the experimental parameters and chose the best condition by determination effective factors. Based on the S/N ratio, the optimized conditions for dye removal were temperature 25 degrees C, initial pH 10, dye concentration 5 ppm, algae type Chlorella and time 2.5h. The stability and efficiency of Chlorella sp. in long-term repetitive operations were also examined.

  16. Biosorption of malachite green from aqueous solutions by Pleurotus ostreatus using Taguchi method.

    PubMed

    Chen, Zhengsuo; Deng, Hongbo; Chen, Can; Yang, Ying; Xu, Heng

    2014-03-12

    Dyes released into the environment have been posing a serious threat to natural ecosystems and aquatic life due to presence of heat, light, chemical and other exposures stable. In this study, the Pleurotus ostreatus (a macro-fungus) was used as a new biosorbent to study the biosorption of hazardous malachite green (MG) from aqueous solutions. The effective disposal of P. ostreatus is a meaningful work for environmental protection and maximum utilization of agricultural residues.The operational parameters such as biosorbent dose, pH, and ionic strength were investigated in a series of batch studies at 25°C. Freundlich isotherm model was described well for the biosorption equilibrium data. The biosorption process followed the pseudo-second-order kinetic model. Taguchi method was used to simplify the experimental number for determining the significance of factors and the optimum levels of experimental factors for MG biosorption. Biosorbent dose and initial MG concentration had significant influences on the percent removal and biosorption capacity. The highest percent removal reached 89.58% and the largest biosorption capacity reached 32.33 mg/g. The Fourier transform infrared spectroscopy (FTIR) showed that the functional groups such as, carboxyl, hydroxyl, amino and phosphonate groups on the biosorbent surface could be the potential adsorption sites for MG biosorption. P. ostreatus can be considered as an alternative biosorbent for the removal of dyes from aqueous solutions.

  17. Adsorption of malachite green by polyaniline-nickel ferrite magnetic nanocomposite: an isotherm and kinetic study

    NASA Astrophysics Data System (ADS)

    Patil, Manohar R.; Shrivastava, V. S.

    2014-11-01

    This work deals with the development of an efficient method for the removal of a MG (malachite green) dye from aqueous solution using polyaniline (PANI)-Nickel ferrite (NiFe2O4) magnetic nanocomposite. It is successfully synthesised in situ through self polymerisation of monomer aniline. Adsorptive removal studies are carried out for water soluble MG dye using PANI-Nickel ferrite magnetic nanocomposite in aqueous solution. Different parameters like dose of adsorbent, contact time, different initial conc., and pH have been studied to optimise reaction condition. It is concluded that adsorptive removal by PANI-Nickel ferrite magnetic nanocomposite is an efficient method for removing a MG dye from aqueous solution than work done before. The optimum conditions for the removal of the dye are initial concentration 30 mg l-1, adsorbent dose 5gm l-1 and pH 7. The adsorption capacity is found 4.09 mg g-1 at optimum condition 30 mg l-1. The adsorption followed pseudo-second-order kinetics. The experimental isotherm is found to fit with Langmuir equation. The prepared adsorbent is characterised by techniques SEM, EDS, XRD and VSM.

  18. Efficient photo-catalytic degradation of malachite green using nickel tungstate material as photo-catalyst.

    PubMed

    Helaïli, N; Boudjamaa, A; Kebir, M; Bachari, K

    2017-01-10

    The present study focused on the evaluation of photo-catalytic and photo-electrochemical properties of the photo-catalyst based on nickel tungstate material prepared by a nitrate method through the degradation of malachite green (MG) dye's. The effect of catalyst loading and dye concentration was examined. Physico-chemical, optical, electrical, electrochemical, and photo-electrochemical properties of the prepared material were analyzed by X-ray diffraction (XRD), fourier transform-infrared spectroscopy (FTIR), BET analysis, optical reflectance diffuse (DR), scanning electron microscopy (SEM/EDX), electrical conductivity, cyclic voltammetry (CV), current intensity, mott-shottky, and nyquist. XRD revealed the formation of monoclinic structure with a small particle size. BET surface area of the sample was around 10 m(2)/g. The results show that the degradation of MG was more than 80%, achieved after 3 h of irradiation at pH 4.6 and with a catalyst loading of 75 mg. Also, it was found that the dye photo-degradation obeyed the pseudo-first order kinetic via Langmuir Hinshelwood model.

  19. Functionalization of sawdust with monosodium glutamate for enhancing its malachite green removal capacity.

    PubMed

    Gong, Renmin; Feng, Min; Zhao, Jiajing; Cai, Wenkai; Liu, Lingling

    2009-01-01

    In this paper, waste sawdust was functionalized by monosodium glutamate for improving its cationic sorption capacity. The functionalized sawdust (FS) and crude sawdust (CS) were compared for their malachite green (MG) sorption behaviors with a batch system. The effects of various experimental parameters (e.g. initial pH, sorbent dose, dye concentration, contact time, and temperature etc.) were investigated and the sorption kinetic and thermodynamic characteristics were understood. The MG removal ratios on FS and on CS increased with increasing initial pH and came up to the maximum value beyond pH 6 for FS and pH 8 for CS, respectively. The ratio of sorbed MG kept above 95% for 250 mg/l of MG solution when 2.0 g/l or more of FS was used. The MG removal percentage decreased more on CS than on FS with increasing initial MG concentration. The isothermal data of MG sorbed on FS and on CS followed the Langmuir model. By functionalizing, the sorption capacity (Q(m)) of sawdust for MG was increased from 85.47 to 196.08 mg/g and the sorption equilibrium time of MG was shortened from 23 to 4.5 h. The MG sorption processes on FS and on CS followed the pseudo-second-order rate kinetics. The sorptions of MG on FS and on CS were spontaneous and exothermic processes and lower temperatures were favorable for the sorption processes.

  20. Determination of malachite green in aquatic products based on magnetic molecularly imprinted polymers.

    PubMed

    Lin, Zheng-zhong; Zhang, Hong-yuan; Peng, Ai-hong; Lin, Yi-dong; Li, Lu; Huang, Zhi-yong

    2016-06-01

    Magnetic molecularly imprinted polymers (MMIPs) were synthesized through precipitation polymerization using malachite green (MG) as template, methacrylic acid as monomer, ethylene dimethacrylate as crosslinker, and Fe3O4 magnetite as magnetic component. MMIPs were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, and vibrating sample magnetometry. Under the optimum condition, the MMIPs obtained exhibited quick binding kinetics and high affinity to MG in the solution. Scatchard plot analysis revealed that the MMIPs contained only one type of binding site with dissociation constant of 24.0 μg mL(-1). The selectivity experiment confirmed that the MMIPs exhibited higher selective binding capacity for MG than its structurally related compound (e.g., crystal violet). As a sorbent for the extraction of MG in sample preparation, MMIPs together with the absorbed analytes could easily be separated from the sample matrix with an external magnet. After elution with methanol/acetic acid (9:1, v/v), MG in the eluent was determined by high-performance liquid chromatography coupled with UV detector with recoveries of 94.0-115%. Results indicated that the as-prepared MMIPs are promising materials for MG analysis in aquatic products.

  1. Adsorption of malachite green by magnetic litchi pericarps: A response surface methodology investigation.

    PubMed

    Zheng, Hao; Qi, Jinqiu; Jiang, Ruixue; Gao, Yan; Li, Xiaochen

    2015-10-01

    In this work, we synthesized a novel magnetic adsorbent containing litchi pericarps, denoted as MLP, for the removal of malachite green (MG) from solution. The factors influencing MG adsorption, such as contact time, adsorbent dosage, and initial dye concentration, were optimized using the Box-Behnken response surface methodology (RSM). The adsorption isotherms as well as the kinetics and thermodynamics of the adsorption of MG onto MLP are discussed. The results showed that MLP has a maximum adsorption efficiency of 99.5% when the temperature, pH, contact time, adsorbent dosage, and initial MG concentration were optimally set as 25 °C, 6.0, 66.69 min, 5.14 g/L, and 150 mg/L, respectively. The best model to describe this process is the Langmuir isotherm, with the maximum adsorption capacity being 70.42 mg/g. In addition, the kinetics of MG adsorption onto MLP followed a pseudo-second-order model; moreover, thermodynamic analysis suggested that MG adsorption onto MLP is spontaneous and endothermic. Finally, it was found that the new magnetic adsorbent can be separated easily and rapidly from mixed solutions in the presence of an external magnetic field.

  2. Bioremoval of the synthetic dye malachite green by marine Trichoderma sp.

    PubMed

    Saravanakumar, Kandasamy; Kathiresan, Kandasamy

    2014-01-01

    In the present study, a marine strain of Trichoderma sp was used for degradation of a synthetic dye, malachite green. Individual and interaction effects of the physical and chemical factors that influenced the percentage of dye degradation were tested by response surface methodology. For optimization, enzyme production and dye degradation were assessed under different temperatures (5-40°C), pH values (3-11), yeast extract (5-9 g L(-1)) and incubation period (0-15 days). The optimum conditions found for dye degradation, were 30°C, pH 5.8, 5.81 mg L(-1) yeast extract for an incubation period of 10 days. Whereas for laccase production they were 29°C, pH 5.3, 7.7 mg L(-1) yeast extract for an incubation period of 12 days. It was confirmed that laccase production required the higher nitrogen source. Degradation of dye was confirmed by using analytical techniques such as FTIR, UV-vis spectral and scanning electron microscope analysis. Furthermore, toxicity effect of degraded and undegraded dye solutions was tested with Artemia salina. Hundred percent mortality was observed in undegraded dye solution as against only 2-5% in degraded dye solution. This work proved the potential of marine strain of Trichoderma Hypocrea lixii on dye degradation.

  3. Wavelength dependent resonance Raman band intensity of broadband stimulated Raman spectroscopy of malachite green in ethanol

    NASA Astrophysics Data System (ADS)

    Cen, Qiongyan; He, Yuhan; Xu, Mei; Wang, Jingjing; Wang, Zhaohui

    2015-03-01

    Resonance broadband stimulated Raman spectroscopy of malachite green in ethanol has been performed. With a tuning picosecond visible laser source and a broadband Raman probe, the Raman gain and loss spectra have been measured simultaneously. By scanning the Raman pump across the first absorption band of the molecule, we found that the resonant Raman bands could be only seen when the pump laser tuned in the range of the red edge of the S1←S0 transition. Dispersive lineshapes of resonant Raman bands have been observed in the Raman loss spectra, while the line shape is normal (same as spontaneous Raman) in the Raman gain spectra. Although, the resonant bands in the loss spectrum are usually stronger than that in the gain spectrum, the band intensities of both loss and gain linearly increase with the pump energy. The relative magnitude of each corresponding resonant band in the Raman loss and gain varies with the pump wavelength. Mode specified Raman excitation profiles have been obtained through broadband stimulated Raman measurement.

  4. Biosorption of malachite green from aqueous solutions by Pleurotus ostreatus using Taguchi method

    PubMed Central

    2014-01-01

    Dyes released into the environment have been posing a serious threat to natural ecosystems and aquatic life due to presence of heat, light, chemical and other exposures stable. In this study, the Pleurotus ostreatus (a macro-fungus) was used as a new biosorbent to study the biosorption of hazardous malachite green (MG) from aqueous solutions. The effective disposal of P. ostreatus is a meaningful work for environmental protection and maximum utilization of agricultural residues. The operational parameters such as biosorbent dose, pH, and ionic strength were investigated in a series of batch studies at 25°C. Freundlich isotherm model was described well for the biosorption equilibrium data. The biosorption process followed the pseudo-second-order kinetic model. Taguchi method was used to simplify the experimental number for determining the significance of factors and the optimum levels of experimental factors for MG biosorption. Biosorbent dose and initial MG concentration had significant influences on the percent removal and biosorption capacity. The highest percent removal reached 89.58% and the largest biosorption capacity reached 32.33 mg/g. The Fourier transform infrared spectroscopy (FTIR) showed that the functional groups such as, carboxyl, hydroxyl, amino and phosphonate groups on the biosorbent surface could be the potential adsorption sites for MG biosorption. P. ostreatus can be considered as an alternative biosorbent for the removal of dyes from aqueous solutions. PMID:24620852

  5. UV light induced photodegradation of malachite green on TiO2 nanoparticles.

    PubMed

    Chen, C C; Lu, C S; Chung, Y C; Jan, J L

    2007-03-22

    The photodegradation of malachite green (MG), a cationic triphenylmethane dye, is examined both under different pH values and amounts of TiO(2). After 15W UV-365nm irradiation for 4h, ca. 99.9% of MG was degraded with addition of 0.5gL(-1) TiO(2) to solutions containing 50mgL(-1) of the MG dye. The HPLC-PDA-ESI-MS technique was used to obtain a better understanding on the mechanistic details of this TiO(2)-assisted photodegradation of the MG dye with UV irradiation. Five intermediates of the process were separated, identified, and characterized for the first time. The results indicated that the N-de-methylation degradation of MG dye took place in a stepwise manner to yield mono-, di-, tri-, and tetra-N-de-methylated MG species generated during the processes. Under acidic conditions, the results indicated that the photodegradation mechanism is favorable to cleavage of the whole conjugated chromophore structure of the MG dye. Under basic conditions, the results showed that the photodegradation mechanism is favorable to a formation of a series of N-de-methylated intermediates of the MG dye.

  6. Photodegradation of malachite green under natural sunlight irradiation: kinetic and toxicity of the transformation products.

    PubMed

    Pérez-Estrada, L A; Agüera, A; Hernando, M D; Malato, S; Fernández-Alba, A R

    2008-02-01

    This article describes the photolytic degradation of malachite green (MG), a cationic triphenylmethane dye used worldwide as a fungicide and antiseptic in the aquaculture industry. Photolysis experiments were performed by direct exposure of a solution of MG in water to natural sunlight. The main transformation products (TPs) generated during the process were identified by liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) and gas chromatography mass spectrometry (GC-MS). The 28 TPs identified with this strategy indicate that MG undergoes three main reactions, N-demethylation, hydroxylation and cleavage of the conjugated structure forming benzophenone derivatives. These processes involve hydroxyl radical attack on the phenyl ring, the N,N-dimethylamine group and the central carbon atom. The Vibrio fischeri acute toxicity test showed that the solution remains toxic after MG has completely disappeared. This toxicity could be assigned, at least in part, to the formation of 4-(dimethylamine)benzophenone, which has an EC(50,30 min) of 0.061 mg l(-1), and is considered "very toxic to aquatic organisms" by current EU legislation.

  7. Spent coffee grounds-based activated carbon preparation for sequestering of malachite green

    NASA Astrophysics Data System (ADS)

    Lim, Jun-Wei; Lam, Keat-Ying; Bashir, Mohammed J. K.; Yeong, Yin-Fong; Lam, Man-Kee; Ho, Yeek-Chia

    2016-11-01

    The key of reported work was to optimize the fabricating factors of spent coffee grounds-based activated carbon (SCG-bAC) used to sequester Malachite Green (MG) form aqueous solution via adsorption process. The fabricating factors of impregnation ratio with ortho-phosphoric acid, activation temperature and activation time were simultaneously optimized by central composite design (CCD) of response surface methodology (RSM) targeting on maximum removal of MG. At the optimum condition, 96.3% of MG was successfully removed by SCG-bAC at the impregnation ratio with ortho-phosphoric acid of 0.50, activation temperature of 554°C and activation time of 31.4 min. Statistical model that could predict the MG removal percentage was also derived and had been statistically confirmed to be significant. Subsequently, the MG adsorption equilibrium data was found well-fitted to Langmuir isotherm model, indicating the predominance of monolayer adsorption of MG on SCG-bAC surface. To conclude, the findings from the this study unveil the potential of spent coffee grounds as an alternative precursor in fabricating low-cost AC for the treatment of wastewater loaded with MG pollutant.

  8. Laccase-Catalyzed Decolorization of Malachite Green: Performance Optimization and Degradation Mechanism

    PubMed Central

    Yang, Jie; Yang, Xiaodan; Lin, Yonghui; Ng, Tzi Bun; Lin, Juan; Ye, Xiuyun

    2015-01-01

    Malachite green (MG) was decolorized by laccase (LacA) of white-rot fungus Cerrena sp. with strong decolorizing ability. Decolorization conditions were optimized with response surface methodology. A highly significant quadratic model was developed to investigate MG decolorization with LacA, and the maximum MG decolorization ratio of 91.6% was predicted under the conditions of 2.8 U mL-1 LacA, 109.9 mg L-1 MG and decolorization for 172.4 min. Kinetic studies revealed the Km and kcat values of LacA toward MG were 781.9 mM and 9.5 s-1, respectively. UV–visible spectra confirmed degradation of MG, and the degradation mechanism was explored with liquid chromatography–mass spectrometry (LC-MS) analysis. Based on the LC-MS spectra of degradation products, LacA catalyzed MG degradation via two simultaneous pathways. In addition, the phytotoxicity of MG, in terms of inhibition on seed germination and seedling root elongation of Nicotiana tabacum and Lactuca sativa, was reduced after laccase treatment. These results suggest that laccase of Cerrena was effective in decolorizing MG and promising in bioremediation of wastewater in food and aquaculture industries. PMID:26020270

  9. Adsorption of neutral red and malachite green onto grapefruit peel in single and binary systems.

    PubMed

    Zou, Weihua; Gao, Shuaipeng; Zou, Xiuli; Bai, Hongjuan

    2013-05-01

    This study characterized the properties of NaOH-modified grapefruit peel (MGP) and investigated its adsorption properties, specifically the adsorption of the synthetic dyes neutral red (NR) and malachite green (MG) onto MGP, in single and binary systems by means of batch techniques. The adsorption equilibrium data of NR onto MGP fit well with both the Langmuir and Koble-Corrigan models, while the Koble-Corrigan and Dubinin-Radushkevich models seemed to agree better with MG adsorption. The maximum equilibrium quantities of NR and MG from the Langmuir model were 640.3 and 314.9 mg/g at 298 K, respectively. The Elovich model was a better fit with the kinetic process, which suggested that ion exchange was one of the main mechanisms at work. The thermodynamic parameters of adsorption systems indicated spontaneous and endothermic processes. In the binary system experiments, NR and MG exhibited competitive adsorption. The quantity of MG adsorbed was more strongly influenced by NR, due to the higher affinity of MGP for the latter.

  10. Determination of residues of three triphenylmethane dyes and their metabolites (malachite green, leuco malachite green, crystal violet, leuco crystal violet, and brilliant green) in aquaculture products by LC/MS/MS: first action 2012.25.

    PubMed

    Hurtaud-Pessel, Dominique; Couëdor, Pierrick; Verdon, Eric; Dowell, Dawn

    2013-01-01

    During the AOAC Annual Meeting held from September 30 to October 3, 2012 in Las Vegas, NV, the Expert Review Panel (ERP) on Veterinary Drug Residues reviewed data for the method for determination of residues of three triphenylmethane dyes and their metabolites (malachite green, leuco malachite green, crystal violet, leuco crystal violet, and brilliant green) in aquaculture products by LC/MS/MS, previously published in the Journal of Chromatography A 1218, 1632-1645 (2006). The method data were reviewed and compared to the standard method performance requirements (SMPRs) found in SMPR 2009.001, published in AOAC's Official Methods of Analysis, 19th Ed. (2012). The ERP determined that the data were acceptable, and the method was approved AOAC Official First Action. The method uses acetonitrile to isolate the analyte from the matrix. Then determination is conducted by LCIMS/MS with positive electrospray ionization. Accuracy ranged from 100.1 to 109.8% for samples fortified at levels of 0.5, 0.75, 1.0, and 2.0 microg/kg. Precision ranged from 2.0 to 10.3% RSD for the intraday samples and 1.9 to 10.6% for the interday samples analyzed over 3 days. The described method is designed to accurately operate in the analytical range from 0.5 to 2 microg/kg, where the minimum required performance limit for laboratories has been fixed in the European Union at 2.0 microg/kg for these banned substances and their metabolites. Upper levels of concentrations (1-100 microg/kg) can be analyzed depending on the different optional calibrations used.

  11. One-pot green synthesis of graphene oxide/gold nanocomposites as SERS substrates for malachite green detection.

    PubMed

    Fu, Wen Liang; Zhen, Shu Jun; Huang, Cheng Zhi

    2013-05-21

    In this contribution, graphene oxide/gold nanoparticle (GO/AuNPs) hybrids were in situ fabricated through a green one-pot procedure by using tyrosine as an environment friendly and biocompatible reducing agent, which can be used as highly efficient surface enhanced Raman scattering (SERS) substrates with the enhancement factor at 3.8 × 10(3). The as-prepared GO/AuNPs hybrids have good biocompatibility, providing the prospect of applications for biomedicine determinations. In addition, taking the advantages of the electromagnetic and chemical enhancement mechanism and the high affinity of GO and AuNPs towards positive dyes, a sensitive, selective and label-free malachite green (MG) detection method was demonstrated. The SERS measurement showed that the minimum detection concentration of MG in water was as low as 2.5 μmol L(-1) with a linear response range from 2.5 to 100 μmol L(-1) (R(2) = 0.996). Moreover, this method can be applied to detect MG in a fishery water sample with satisfactory results.

  12. Surfactant-modified alumina: an efficient adsorbent for malachite green removal from water environment.

    PubMed

    Das, Asit K; Saha, Sandip; Pal, Anjali; Maji, Sanjoy K

    2009-07-15

    Surface of alumina was modified with sodium dodecyl sulfate (SDS), an anionic surfactant. The surfactant-modified alumina (SMA) was characterized by FTIR and thermal analysis. The SMA was then used for the removal of malachite green (MG; Basic Green 4), a well-known toxic cationic dye from aqueous environment. The removal of MG takes place in the micellar structure formed on alumina surface, and the process is called adsolubilization. All the studies were carried out in batch mode. The kinetic studies showed that 1 h contact time was sufficient to attain equilibrium. SMA was very efficient to remove MG up to 99% under optimum conditions. The concentration range of MG was 20-100 mg/L. The isotherm studies showed that it follows Langmuir model better than the Freundlich model. The maximum adsorption capacity was 185 mg/g. The effects of various parameters such as pH, presence of interfering ions (Cl-, NO3-, H2PO4-, SO4(2-), Fe2+, Ca2+) and organics (pesticides such as 2,4-dichlorophenoxyacetic acid, atrazine, endosulfan, and humic acid) are evaluated. It was observed that H2PO4-, Fe2+, endosulfan, and humic acid have maximum interference. Desorption of MG from exhausted SMA using acetone, and its reuse was studied. The regenerated adsorbent shows approximately 80% efficiency on the removal of MG. The usability of SMA for the removal of MG from real wastewater was also examined. The kinetic equilibrium was attained within 1 h and the removal could be achieved up to approximately 95% at a dose of 20 g/L. The adsorption followed Freundlich isotherm model better than the Langmuir model.

  13. [Fe₃O₄-β-Cyclodextrin Polymer Nano Composites Solid-Phase Extraction-UV-Vis Spectrophotometry for Separation Analysis Malachite Green].

    PubMed

    Feng, Gang; Ping, Wen-hui; Zhu, Xia-shi

    2016-02-01

    In this paper, carboxymethyl-hydroxypropyl-β-cyclodextrin polymer modified magnetic particles Fe₃O₄ (CM-HP-β-CD- CP-MNPs) were prepared and applied to magnetic solid phase extraction of malachite green combined with UV-Visible spectrom- etry detection. The synthesized magnetic particles were characterized by element analysis, Fourier transform infrared spectra and transmission electron microscopy. Several variables affecting the extraction and desorption of malachite green such as pH, the amount of adsorbent, the type and volume of eluent, extraction and desorption time, and temperature were investigated. Under the optimum conditions, malachite green could be adsorbed by CM-HP-β-CDCP-MNPs (RE% = 92), and elution by C₂H₅OH (EE% = 90). the preconcentration factor of the proposed method was approximately 7.5, the CM-HP-β-CDCP-MNPs could be used repeatedly for 5 times and offered better recovery. The linear range and detection limit (DL) were found to be 0.08~8.00 µg · mL⁻¹ and 5.6 ng · mL⁻¹ respectively. This technique had been successfully applied to the determination of malachite green in real samples. The inclusion interaction of CM-HP--CDCP-MNPs with malachite green was studied through FTIR.

  14. Molecularly imprinted polymer for selective extraction of malachite green from seawater and seafood coupled with high-performance liquid chromatographic determination.

    PubMed

    Lian, Ziru; Wang, Jiangtao

    2012-12-01

    In this paper, a highly selective sample cleanup procedure combining molecular imprinting technique (MIT) and solid-phase extraction (SPE) was developed for the isolation of malachite green in seawater and seafood samples. The molecularly imprinted polymer (MIP) was prepared using malachite green as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The imprinted polymer and non-imprinted polymer were characterized by scanning electron microscope and static adsorption experiments. The MIP showed a high adsorption capacity and was used as selective sorbent for the SPE of malachite green. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chromatography with diodearray detection for the analysis of malachite green in seawater and seafood samples was also established. Finally, five samples were determined. The results showed that malachite green concentration in one seawater sample was at 1.30 μg L⁻¹ and the RSD (n=3) was 4.15%.

  15. Adsorption of malachite green on groundnut shell waste based powdered activated carbon

    SciTech Connect

    Malik, R.; Ramteke, D.S. Wate, S.R.

    2007-07-01

    In the present technologically fast changing situation related to waste management practices, it is desirable that disposal of plant waste should be done in a scientific manner by keeping in view economic and pollution considerations. This is only possible when the plant waste has the potential to be used as raw material for some useful product. In the present study, groundnut shell, an agricultural waste, was used for the preparation of an adsorbent by chemical activation using ZnCl{sub 2} under optimized conditions and its comparative characterisation was conducted with commercially available powdered activated carbon (CPAC) for its physical, chemical and adsorption properties. The groundnut shell based powdered activated carbon (GSPAC) has a higher surface area, iodine and methylene blue number compared to CPAC. Both of the carbons were used for the removal of malachite green dye from aqueous solution and the effect of various operating variables, viz. adsorbent dose (0.1-1 g l{sup -1}), contact time (5-120 min) and adsorbate concentrations (100-200 mg l{sup -1}) on the removal of dye, has been studied. The experimental results indicate that at a dose of 0.5 g l{sup -1} and initial concentration of 100 mg l{sup -1}, GSPAC showed 94.5% removal of the dye in 30 min equilibrium time, while CPAC removed 96% of the dye in 15 min. The experimental isotherm data were analyzed using the linearized forms of Freundlich, Langmuir and BET equations to determine maximum adsorptive capacities. The equilibrium data fit well to the Freundlich isotherm, although the BET isotherm also showed higher correlation for both of the carbons. The results of comparative adsorption capacity of both carbons indicate that groundnut shell can be used as a low-cost alternative to commercial powdered activated carbon in aqueous solution for dye removal.

  16. Use of Malachite Green-Loop Mediated Isothermal Amplification for Detection of Plasmodium spp. Parasites.

    PubMed

    Lucchi, Naomi W; Ljolje, Dragan; Silva-Flannery, Luciana; Udhayakumar, Venkatachalam

    2016-01-01

    Malaria elimination efforts are hampered by the lack of sensitive tools to detect infections with low-level parasitemia, usually below the threshold of standard diagnostic methods, microscopy and rapid diagnostic tests. Isothermal nucleic acid amplification assays such as the loop-mediated isothermal amplification (LAMP), are well suited for field use as they do not require thermal cyclers to run the test. However, the use of specialized equipment, as described by many groups, reduces the versatility of the LAMP technique as a simple tool for use in endemic countries. In this study, the use of the malachite green (MG) dye, as a visual endpoint readout, together with a simple mini heat block was evaluated for the detection of malaria parasites. The assay was performed for 1 hour at 63°C and the results scored by 3 independent human readers. The limit of detection of the assay was determined using well-quantified Plasmodium spp. infected reference samples and its utility in testing clinical samples was determined using 190 pre-treatment specimens submitted for reference diagnosis of imported malaria in the United States. Use of a simplified boil and spin methods of DNA extraction from whole blood and filter paper was also investigated. We demonstrate the accurate and sensitive detection of malaria parasites using this assay with a detection limit ranging between 1-8 parasites/μL, supporting its applicability for the detection of infections with low parasite burden. This assay is compatible with the use of a simple boil and spin sample preparation method from both whole blood and filter papers without a loss of sensitivity. The MG-LAMP assay described here has great potential to extend the reach of molecular tools to settings where they are needed.

  17. Synthesis of Large Pore Carbon Nanoparticles for Removal of Malachite Green.

    PubMed

    Tripathi, Pranav K; Gan, Lihua; Liu, Mingxian

    2016-01-01

    In this work, we have synthesized high surface area and large pore volume carbon nanoparticles (CNP) by a simple and easy sol-gel approach. The sol was prepared by mixing Pluronic F127 and phloroglucinol-terephthalaldehyde in acidic ethanol solution and the gel was formed after the vacuum removal of ethanol. In the sol-gel process, hydrophobic segments of Pluronic F127 forms enhanced hydrogen bonding with trihydroxyl groups of phloroglucinol. A polymeric network of carbon precursor was also prepared by making the interconnectivity between four phloroglucinol and one terephthalaldehyde molecules. After thermal polymerization and carbonization of the gel, the CNP had a very high surface area (1441 m² g⁻¹) and large pore volume (1.7 cm³ g⁻¹) with narrow micropore (1.0 nm) and mesopore (2.3 nm) diameters. The mesopore was developed due to the enhanced hydrogen bonding between Pluronic F127 and phloroglucinol, while the micropores were generated due to hydrocarbon polymeric network of phloroglucinol-terephthalaldehyde. The CNP had a size about ca. 20 nm. The CNP were applied for the removal of the highly hazardous water pollutant malachite green (MG) and achieved a very high adsorption capacity (1892 mg g⁻¹). The commercials powder activated carbon (PAC) was also applied for the removal of MG and achieved an adsorption capacity of PAC was 1390 mg g⁻¹. It believes that shape and size of CNP and PAC played an important role in the adsorptive removal of MG.

  18. Use of Malachite Green-Loop Mediated Isothermal Amplification for Detection of Plasmodium spp. Parasites

    PubMed Central

    Lucchi, Naomi W.; Ljolje, Dragan; Silva-Flannery, Luciana; Udhayakumar, Venkatachalam

    2016-01-01

    Malaria elimination efforts are hampered by the lack of sensitive tools to detect infections with low-level parasitemia, usually below the threshold of standard diagnostic methods, microscopy and rapid diagnostic tests. Isothermal nucleic acid amplification assays such as the loop-mediated isothermal amplification (LAMP), are well suited for field use as they do not require thermal cyclers to run the test. However, the use of specialized equipment, as described by many groups, reduces the versatility of the LAMP technique as a simple tool for use in endemic countries. In this study, the use of the malachite green (MG) dye, as a visual endpoint readout, together with a simple mini heat block was evaluated for the detection of malaria parasites. The assay was performed for 1 hour at 63°C and the results scored by 3 independent human readers. The limit of detection of the assay was determined using well-quantified Plasmodium spp. infected reference samples and its utility in testing clinical samples was determined using 190 pre-treatment specimens submitted for reference diagnosis of imported malaria in the United States. Use of a simplified boil and spin methods of DNA extraction from whole blood and filter paper was also investigated. We demonstrate the accurate and sensitive detection of malaria parasites using this assay with a detection limit ranging between 1–8 parasites/μL, supporting its applicability for the detection of infections with low parasite burden. This assay is compatible with the use of a simple boil and spin sample preparation method from both whole blood and filter papers without a loss of sensitivity. The MG-LAMP assay described here has great potential to extend the reach of molecular tools to settings where they are needed. PMID:26967908

  19. Sonocatalytic degradation of malachite green oxalate by a semiconductor metal oxide nanocatalyst.

    PubMed

    Bhavani, R; Sivasamy, A

    2016-12-01

    Advanced Oxidation Process (AOP) technologies are considered to be better technique for the degradation or mineralization of many recalcitrant compounds and pollutants. In the present study heterogeneous sonocatalytic degradation of a model organic compound such as Malachite green oxalate (MGO) was carried out in the aqueous phase. Zinc oxide nanorods were prepared by precipitation method employing zinc acetates as precursors and were characterized by FT-IR, XRD, FE-SEM and EDAX analysis. Degradation of MGO in the aqueous phase was studied in detail under the sonocatalytic process. Effects of pH, dye concentration, oxidant concentration, kinetics and effect of electrolytes on dye degradation were carried out to check the efficiency of the sonocatalyst. Effect of energy input on the degradation processes was also investigated. The degradation of dye molecules were monitored by UV-visible spectrophotometer and Chemical Oxygen demand (COD). The dye molecules were readily degraded at above 90% in the pH range 5.0-7.0 under ultrasound with zinc oxide nanorods. The interference of electrolytes like NaCl, KCl, Na2CO3, NaHCO3 and MgSO4 on the degradation of dye molecules were also studied on the sonocatalytic degradation of MGO. From the kinetic studies it was observed that at lower initial concentration of dye molecules the degradation efficiency was above 90%. The rate of the reaction decreased on increasing the initial dye concentrations of the dye molecules. It was observed that the complete mineralization of dye molecules was achieved without the formation of toxic by-products. The reusability of the catalyst also showed the effective degradation of the dye molecules up to five cycles without loss of the catalytic activities.

  20. Removal of malachite green from aqueous solution by activated carbon prepared from the epicarp of Ricinus communis by adsorption.

    PubMed

    Santhi, T; Manonmani, S; Smitha, T

    2010-07-15

    The use of low-cost, locally available, highly efficient and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from the epicarp of Ricinus communis for the removal of malachite green (MG) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were investigated and optimal experimental conditions were ascertained. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Optimum pH value for dye adsorption was 7.0. Maximum dye was sequestered within 50 min of the start of every experiment. The adsorption of malachite green followed the pseudo-second-order rate equation and fits the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Tempkin equations well. The maximum removal of MG was obtained at pH 7 as 99.04% for adsorbent dose of 1 g 50 mL(-1) and 25 mg L(-1) initial dye concentration at room temperature. Activated carbon developed from R. communis can be an attractive option for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater showed better removal percentage of MG.

  1. An enzyme-free strategy for ultrasensitive detection of adenosine using a multipurpose aptamer probe and malachite green.

    PubMed

    Zhao, Hui; Wang, Yong-Sheng; Tang, Xian; Zhou, Bin; Xue, Jin-Hua; Liu, Hui; Liu, Shan-Du; Cao, Jin-Xiu; Li, Ming-Hui; Chen, Si-Han

    2015-08-05

    We report on an enzyme-free and label-free strategy for the ultrasensitive determination of adenosine. A novel multipurpose adenosine aptamer (MAAP) is designed, which serves as an effective target recognition probe and a capture probe for malachite green. In the presence of adenosine, the conformation of the MAAP is converted from a hairpin structure to a G-quadruplex. Upon addition of malachite green into this solution, a noticeable enhancement of resonance light scattering was observed. The signal response is directly proportional to the concentration of adenosine ranging from 75 pM to 2.2 nM with a detection limit of 23 pM, which was 100-10,000 folds lower than those obtained by previous reported methods. Moreover, this strategy has been applied successfully for detecting adenosine in human urine and blood samples, further proving its reliability. The mechanism of adenosine inducing MAAP to form a G-quadruplex was demonstrated by a series of control experiments. Such a MAAP probe can also be used to other strategies such as fluorescence or spectrophotometric ones. We suppose that this strategy can be expanded to develop a universal analytical platform for various target molecules in the biomedical field and clinical diagnosis.

  2. Application of ionic liquid-based microwave-assisted extraction of malachite green and crystal violet from water samples.

    PubMed

    Gao, Zhanqi; Liu, Tingfeng; Yan, Xiaoju; Sun, Cheng; He, Huan; Yang, Shaogui

    2013-03-01

    A simple, environment friendly and efficient technique, ionic liquid-based microwave-assisted extraction was first used to determine malachite green and crystal violet (CV) from water samples coupled to HPLC. The key parameters influencing extraction efficiency were investigated, such as the type of ionic liquids, the volume of ionic liquid, extraction time, and so on. Under the optimum conditions, good reproducibility of the extraction performance was obtained (RSD, 1.0% for malachite green (MG) and 5.9% for CV, n = 5). Good linearity (0.10-25 μg L(-1)) was observed with correlation coefficients between 0.9991 and 0.9964. The detection limits of MG and CV were 0.080 and 0.030 μg L(-1), respectively. The proposed method had been successfully applied to determine MG and CV in real water samples with recoveries ranging from 95.4 to 102.8%. Compared with the previous technologies, the proposed method required less extraction time (2 min), and provided lower detection limits and higher enrichment factors. Moreover, there were no volatile and hazardous organic solvents released. Based on these simple, environment friendly, rapid, and highly efficient results, the proposed approach provides a new and promising alternative for simultaneously extracting trace amounts of MG and CV from water.

  3. Removal of malachite green dye from aqueous solution using mesoporous silica synthesized from 1-octyl-3-methylimidazolium chloride ionic liquid

    NASA Astrophysics Data System (ADS)

    Ekka, Basanti; Nayak, Soumitra Ranjan; Dash, Priyabrat; Patel, Raj Kishore

    2016-04-01

    In this research, mesoporous silica was synthesized via a modified sol-gel route using 1-octyl-3-methylimidazolium chloride and was employed to remove malachite green (MG) dye from aqueous solution. Subsequently, this material was characterized and identified by different techniques such as Fourier transform infrared spectroscopy (FT-IR), N2 adsorption-desorption method, scanning electron microscopy (SEM), and thermosgravimetric analysis (TGA). Unique properties such as high surface area and pore diameter, in addition to highly reactive atoms and presence of various functional groups make the mesoporous silica possible for efficient removal of malachite green (MG). In batch experimental set-up, optimum conditions for quantitative removal of MG by mesoporous silica was attained by varying different variables such as adsorbent dosage, initial dye concentration, contact time, and pH. Optimum values were set as pH of 8.0, 0.5 g of adsorbent at contact time of 120 min. The adsorption of MG follows the pseudo-second-order rate equation. Equilibrium data fitted well with the Freundlich model at all amount of adsorbent, while maximum adsorption capacity was 5.981 mg g-1 for 0.5 g mesoporous silica synthesized in IL.

  4. Rhizobium marinum sp. nov., a malachite-green-tolerant bacterium isolated from seawater.

    PubMed

    Liu, Yang; Wang, Run-Ping; Ren, Chong; Lai, Qi-Liang; Zeng, Run-Ying

    2015-12-01

    A motile, Gram-stain-negative, non-pigmented bacterial strain, designated MGL06T, was isolated from seawater of the South China Sea on selection medium containing 0.1 % (w/v) malachite green. Strain MGL06T showed highest 16S rRNA gene sequence similarity to Rhizobium vignae CCBAU 05176T (97.2 %), and shared 93.2-96.9 % with the type strains of other recognized Rhizobium species. Phylogenetic analyses based on 16S rRNA and housekeeping gene sequences showed that strain MGL06T belonged to the genus Rhizobium. Mean levels of DNA-DNA relatedness between strain MGL06T and R. vignae CCBAU 05176T, Rhizobium huautlense S02T and Rhizobium alkalisoli CCBAU 01393T were 20 ± 3, 18 ± 2 and 14 ± 3 %, respectively, indicating that strain MGL06T was distinct from them genetically. Strain MGL06T did not form nodules on three different legumes, and the nodD and nifH genes were also not detected by PCR or based on the draft genome sequence. Strain MGL06T contained Q-10 as the predominant ubiquinone. The major fatty acid was C18 : 1ω7c/C18 : 1ω6c with minor amounts of C19 : 0 cyclo ω8c, C16 : 0 and C18 : 1ω7c 11-methyl. Polar lipids of strain MGL06T included unknown glycolipids, phosphatidylcholine, aminolipid, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unknown polar lipid and aminophospholipid. Based on its phenotypic and genotypic data, strain MGL06T represents a novel species of the genus Rhizobium, for which the name Rhizobium marinum sp. nov. is proposed. The type strain is MGL06T ( = MCCC 1A00836T = JCM 30155T).

  5. Novel guar gum/Al2O3 nanocomposite as an effective photocatalyst for the degradation of malachite green dye.

    PubMed

    Pathania, Deepak; Katwal, Rishu; Sharma, Gaurav; Naushad, Mu; Khan, Mohammad Rizwan; Al-Muhtaseb, Ala'a H

    2016-06-01

    Guar gum/Al2O3 (GG/AO) nanocomposite was prepared using simple and cost effective sol-gel method. This nanocomposite was characterized by several analytical techniques viz. scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermal analysis (TGA/DTA), Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-vis). The FTIR analysis confirmed that GG/AO composite material was formed. TEM images inferred the particle size in the range between 20 and 45nm. GG/AO nanocomposite exhibited good photocatalytic performance for malachite green (MG) dye (dye initial concentration 1.5×10(-5)M) degradation from aqueous phase. The adsorption followed by photocatalysis and coupled adsorption/photocatalysis reaction achieved about 80% and 90% degradation of MG dye under solar irradiation. Antibacterial test showed the excellent activity of GG/AO nanocomposite against Staphylococcus aureus.

  6. Malachite green bioremoval by a newly isolated strain Citrobacter sedlakii RI11; enhancement of the treatment by biosurfactant addition.

    PubMed

    Mnif, Inès; Fendri, Raouia; Ghribi, Dhouha

    2015-01-01

    Citrobacter sedlackii RI11, isolated from acclimated textile effluent after selective enrichment on synthetic dyes, was assessed for malachite green (MG) biotreatment potency. Results indicate that this bacterium has potential for use in effective treatment of MG contaminated wastewaters under shaking conditions at neutral and alkaline pH value, characteristic of typical textile effluents. Also, the newly isolated strain can tolerate higher doses of dye and decolorize up to 1,000 mg/l of dye. When used as microbial surfactant to enhance MG biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized the decolorization efficiency at an optimal concentration of biosurfactant of about 0.075%. Studies ensured that MG removal by this strain could be due to biodegradation and/or adsorption. Results on germination potencies of different seeds using the treated dyes under different conditions favor the use of SPB1 biosurfactant for the treatment of MG.

  7. Detoxification of malachite green by Pleurotus florida laccase produced under solid-state fermentation using agricultural residues.

    PubMed

    Sathishkumar, Palanivel; Palvannan, Thayumanavan; Murugesan, Kumarasamy; Kamala-Kannan, Seralathan

    2013-01-01

    Laccase was produced from Pleurotus florida under solid-state fermentation, and the production was optimized by response surface methodology. The predicted maximum laccase production of 8.81 U g(-1) was obtained by the optimum concentration of malt extract, banana peel, wheat bran and CuSO4, which was found to be 0.69 g, 10.61 g, 10.68 g and 77.15 ppm, respectively. The validation results suggested that the laccase production was 7.96 U g(-1) in the optimized medium, which was close to the predicted value. Decolorization efficiency of P. florida laccase was evaluated against malachite green (MG). Rapid decolorization of MG dye was observed, and a dark-coloured precipitate was formed in the reaction mixture. HPLC analysis indicated that the laccase enzyme degraded MG by the demethylation process. The toxicity of MG was reduced to 67% after the treatment with laccase, which was confirmed by a phytotoxicity study.

  8. A malachite green procedure for orthophosphate determination and its use in alkaline phosphatase-based enzyme immunoassay.

    PubMed

    Baykov, A A; Evtushenko, O A; Avaeva, S M

    1988-06-01

    An improved procedure for phosphate determination based on a highly colored complex of phosphomolybdate and malachite green is described. All necessary reagents are combined in one concentrated solution, making the assay sensitive and convenient. The procedure is based on the finding that the dye is easily soluble and stable in the presence of 6 N acid. The addition of Tween 20 is required to stabilize the dye-phosphomolybdate complex at phosphate concentrations above 10 microM. The time of color development at 25 degrees C is about 3 min. The procedure was adopted to measure alkaline phosphate activity in heterogeneous enzyme immunoassay with rho-nitrophenyl phosphate and pyrophosphate as substrates. In both cases, a 4-fold increase in sensitivity in terms of absorbance readings was obtained compared to the standard method based on rho-nitrophenol measurement. In visual analysis, the gain in sensitivity was as high as 20-fold, due to contrast color change (yellow to greenish blue).

  9. Efficient removal of malachite green dye using biodegradable graft copolymer derived from amylopectin and poly(acrylic acid).

    PubMed

    Sarkar, Amit Kumar; Pal, Aniruddha; Ghorai, Soumitra; Mandre, N R; Pal, Sagar

    2014-10-13

    This article reports on the application of a high performance biodegradable adsorbent based on amylopectin and poly(acrylic acid) (AP-g-PAA) for removal of toxic malachite green dye (MG) from aqueous solution. The graft copolymer has been synthesized and characterized using various techniques including FTIR, GPC, SEM and XRD analyses. Biodegradation study suggests that the co-polymer is biodegradable in nature. The adsorbent shows excellent potential (Qmax, 352.11 mg g(-1); 99.05% of MG has been removed within 30 min) for removal of MG from aqueous solution. It has been observed that point to zero charge (pzc) of graft copolymer plays significant role in adsorption efficacy. The adsorption kinetics and isotherm follow pseudo-second order and Langmuir isotherm models, respectively. Thermodynamics parameters suggest that the process of dye uptake is spontaneous. Finally desorption study shows excellent regeneration efficiency of adsorbent.

  10. Simultaneous determination of malachite green, gentian violet and their leuco metabolites in catfish or trout tissue by high-performance liquid chromatography with visible detection.

    PubMed

    Rushing, L G; Thompson, H C

    1997-01-24

    A sensitive analytical procedure for the determination of residues of leucomalachite green (LMG)-malachite green (MG) and leucogentian violet (LGV)-gentian violet (GV) in catfish or trout tissue is presented. Frozen (-20 degrees C) fish fillets were cut into small pieces and blended in a Waring blender. A 20-g amount of homogenized fish tissue was extracted with acetonitrile-buffer, partitioned against methylene chloride, and cleaned up on tandem neutral alumina and propylsulfonic acid cation-exchange solid-phase extraction cartridges. Samples of 100 microliters (0.8 g equiv.) were chromatographed isocratically in 10 min using an acetonitrile-buffer mobile phase on a short-chain deactivated (SCD) reversed-phase column (250 x 4.6 mm I.D.) in-line with a post-column PbO2 oxidation reactor. The PbO2 post-column reactor efficiently oxidized LMG to the chromatic MG, and LGV to the chromatic GV permitting visible detection at 588 nm for all four compounds. Linearity was demonstrated with standards over the range of 0.5-50 ng per injection. Recoveries of LMG, MG, LGV and GV from catfish tissues fortified at 10 ng/g were 75.4 +/- 3.0, 61.3 +/- 4.1, 72.6 +/- 3.7 and 87.9 +/- 2.5, respectively, while trout tissues fortified at 10 ng/g yielded recoveries of 82.6 +/- 2.3, 48.6 +/- 1.8, 72.1 +/- 2.1 and 83.8 +/- 4.6 (mean +/- S.D., n = 4), respectively.

  11. Confirmation of malachite green, gentian violet and their leuco analogs in catfish and trout tissue by high-performance liquid chromatography utilizing electrochemistry with ultraviolet-visible diode array detection and fluorescence detection.

    PubMed

    Rushing, L G; Hansen, E B

    1997-10-24

    A sensitive analytical procedure for the confirmation of residues of malachite green (MG), gentian violet (GV) and their leuco analogs (LMG and LGV) in catfish and trout tissue at 10 ng/g is described. Frozen (-20 degrees C) fish fillets were cut into small pieces and homogenized in Waring blendors. The compounds of interest were extracted from 20-g amounts of homogenized fish tissue with acetonitrile-buffer, partitioned against methylene chloride, and isolated with tandem neutral alumina and propylsulfonic acid cation-exchange solid-phase extraction cartridges. Samples of 100 microl (0.8 g equiv.) were chromatographed isocratically in 10 min using an acetonitrile-buffer mobile phase on a short-chain deactivated (SCD) reversed-phase column (150x4.6 mm I.D.) in-line with a post-column oxidation coulometric electrochemical cell (EC), a UV-Vis diode array detector and a fluorescence detector.

  12. Post-column reaction for simultaneous analysis of chromatic and leuco forms of malachite green and crystal violet by high-performance liquid chromatography with photometric detection

    USGS Publications Warehouse

    Allen, J.L.; Meinertz, J.R.

    1991-01-01

    The chromatic and leuco forms of malachite green and crystal violet were readily separated and detected by a sensitive and selective high-performance liquid chromatographic procedure. The chromatic and leuco forms of the dyes were separated within 11 min on a C18 column with a mobile phase of 0.05 M sodium acetate and 0.05 M acetic acid in water (19%) and methanol (81%). A reaction chamber, containing 10% PbO2 in Celite 545, was placed between the column and the spectrophotometric detector to oxidize the leuco forms of the dyes to their chromatic forms. Chromatic and leuco malachite green were quantified by their absorbance at 618 nm; and chromatic and leuco Crystal Violet by their absorbance at 588 nm. Detection limits for chromatic and leuco forms of both dyes ranged from 0.12 to 0.28 ng. A linear range of 1 to 100 ng was established for both forms of the dyes.

  13. Equilibrium, kinetics and mechanism modeling and simulation of basic and acid dyes sorption onto jute fiber carbon: Eosin yellow, malachite green and crystal violet single component systems.

    PubMed

    Porkodi, K; Vasanth Kumar, K

    2007-05-08

    Batch experiments were carried out for the sorption of eosin yellow, malachite green and crystal violet onto jute fiber carbon (JFC). The operating variables studied are the initial dye concentration, initial solution pH, adsorbent dosage and contact time. Experimental equilibrium data were fitted to Freundlich, Langmuir and Redlich-Peterson isotherm by non-linear regression method. Langmuir isotherm was found to be the optimum isotherm for eosin yellow/JFC system and Freundlich isotherm was found to be the optimum isotherm for malachite green/JFC and crystal violet/JFC system at equilibrium conditions. The sorption capacities of eosin yellow, malachite green and crystal violet onto JFC according to Langmuir isotherm were found to 31.49 mg/g, 136.58 mg/g, 27.99 mg/g, respectively. A single stage batch adsorber was designed for the adsorption of eosin yellow, malachite green and crystal violet onto JFC based on the optimum isotherm. A pseudo second order kinetic model well represented the kinetic uptake of dyes studied onto JFC. The pseudo second order kinetic model successfully simulated the kinetics of dye uptake process. The dye sorption process involves both surface and pore diffusion with predominance of surface diffusion at earlier stages. A Boyd plot confirms the external mass transfer as the rate limiting step in the dye sorption process. The influence of initial dye concentration on the dye sorption process was represented in the form of dimensionless mass transfer numbers (Sh/Sc(0.33)) and was found to be agreeing with the expression:

  14. A Highly Sensitive and Selective Method for the Determination of an Iodate in Table-salt Samples Using Malachite Green-based Spectrophotometry.

    PubMed

    Konkayan, Mongkol; Limchoowong, Nunticha; Sricharoen, Phitchan; Chanthai, Saksit

    2016-01-01

    A simple, rapid, and sensitive malachite green-based spectrophotometric method for the selective trace determination of an iodate has been developed and presented for the first time. The reaction mixture was specifically involved in the liberation of iodine in the presence of an excess of iodide in an acidic condition following an instantaneous reaction between the liberated iodine and malachite green dye. The optimum condition was obtained with a buffer solution pH of 5.2 in the presence of 40 mg L(-1) potassium iodide and 1.5 × 10(-5) M malachite green for a 5-min incubation time. The iodate contents in some table-salt samples were in the range of 26 to 45 mg kg(-1), while those of drinking water, tap water, canal water, and seawater samples were not detectable (< 96 ng mL(-1) of limits of detection, LOQ) with their satisfied method of recoveries of between 93 and 108%. The results agreed with those obtained using ICP-OES for comparison.

  15. Batch removal of malachite green from aqueous solutions by adsorption on oil palm trunk fibre: equilibrium isotherms and kinetic studies.

    PubMed

    Hameed, B H; El-Khaiary, M I

    2008-06-15

    Oil palm trunk fibre (OPTF)--an agricultural solid waste--was used as low-cost adsorbent to remove malachite green (MG) from aqueous solutions. The operating variables studied were contact time, initial dye concentration, and solution pH. Equilibrium adsorption data were analyzed by three isotherms, namely the Freundlich isotherm, the Langmuir isotherm, and the multilayer adsorption isotherm. The best fit to the data was obtained with the multilayer adsorption. The monolayer adsorption capacity of OPTF was found to be 149.35 mg/g at 30 degrees C. Adsorption kinetic data were modeled using the Lagergren pseudo-first-order, Ho's pseudo-second-order and Elovich models. It was found that the Lagergren's model could be used for the prediction of the system's kinetics. The overall rate of dye uptake was found to be controlled by external mass transfer at the beginning of adsorption, then for initial MG concentrations of 25, 50, 100, 150, and 300 mg/L the rate-control changed to intraparticle diffusion at a later stage, but for initial MG concentrations 200 and 250 mg/L no evidence was found of intraparticle diffusion at any period of adsorption. It was found that with increasing the initial concentration of MG, the pore-diffusion coefficient increased while the film-diffusion coefficient decreased.

  16. Reusable nanosilver-coated magnetic particles for ultrasensitive SERS-based detection of malachite green in water samples

    PubMed Central

    Song, Dan; Yang, Rong; Wang, Chongwen; Xiao, Rui; Long, Feng

    2016-01-01

    A novel nanosilver-deposited silica-coated Fe3O4 magnetic particle (Fe3O4@SiO2@Ag) with uniform size, good SERS activity and magnetic responsiveness was synthesized using amination polymer. The Fe3O4@SiO2@Ag magnetic particles have been successfully applied for ultrasensitive SERS detection of malachite green (MG) in water samples. The mechanism is that MG can be adsorbed on the silver surface of nanosilver-coated magnetic particles via one nitrogen atom, and the Raman signal intensity of MG is significantly enhanced by the nanosilver layer formed on the magnetic particles. The developed sensing system exhibited a sensitive response to MG in the range of 10 fM to 100 μM with a low limit of detection (LOD) 2 fM under optimal conditions. The LOD was several orders of magnitude lower than those of other methods. This SERS-based sensor showed good reproducibility and stability for MG detection. The silver-coated magnetic particles could easily be regenerated as SERS substrates only using low pH solution for multiple sensing events. The recovery of MG added to several water samples at different concentrations ranged from 90% to 110%. The proposed method facilitates the ultrasensitive analysis of dyes to satisfy the high demand for ensuring the safety of water sources. PMID:26964502

  17. HPLC determination and MS confirmation of malachite green, gentian violet, and their leuco metabolite residues in channel catfish muscle.

    PubMed

    Chen, Guoying; Miao, Shui

    2010-06-23

    Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in channel catfish muscle were individually determined by HPLC using diode array and fluorescence detectors and confirmed by tandem mass spectrometry. This detection scheme obviates a PbO(2) reactor that converts leuco forms to chromatic forms for absorbance detection, therefore eliminating uncertainties in oxidant depletion and data integrity. Extraction was performed once in pH 3 McIlvaine buffer and acetonitrile, followed by cleanup using a polymeric strong cation-exchange column. Liquid-liquid extraction was excluded to provide an environmentally responsible and relatively rapid protocol. Spectrometric limits of detection (LOD; S/N = 3) for MG (lambda = 620 nm) and GV (lambda = 588 nm) were 0.38 and 0.26 ng/g with 44.5-49.2% and 92.2-101.4% recoveries (1-10 ng/g, n = 6), respectively. Fluorometric LOD (S/N = 3) for LMG and LGV (lambda(ex) = 266 nm, lambda(em) = 360 nm) were 0.10 and 0.09 ng/g with 74.3-84.5% and 80.6-86.5% recoveries (1-10 ng/g, n = 6), respectively. This simplified protocol saves costs and meets the sensitivity requirements set by the Food and Drug Administration and the European Union.

  18. Biological decolorization of dye solution containing malachite green by Pandoraea pulmonicola YC32 using a batch and continuous system.

    PubMed

    Chen, Chih-Yu; Kuo, Jong-Tar; Cheng, Chiu-Yu; Huang, Yu-Tang; Ho, I-Hsin; Chung, Ying-Chien

    2009-12-30

    In our study, we have isolated a relatively newly identified bacteria species, Pandoraea pulmonicola YC32, and first assessed its capability to treat malachite green (MG). The effects of various factors on decolorization efficiency were investigated in a batch system. The decolorization efficiency was found to be optimal within a pH of 7-10 and it increased, with increasing initial MG concentration up to 100 mg/l. The relationship between the decolorization rate and MG concentration agreed with Lineweaver-Burk equation. The apparent kinetic parameters, R(MG,max) and K(m), were 6.23 mg-MG/g-cell/h and 153.4 mg/l, respectively. The initial step in the biodegradation pathway of MG by P. pulmonicola YC32 was a reduction or N-demethylation reaction. We achieved a decolorization efficiency of 85.2% with 50mg/l MG in the immobilized P. pulmonicola YC32 continuous column system. This is the first report on the application of a continuous column system to decolorize MG using a microorganism.

  19. Comparative analysis and validation of the malachite green assay for the high throughput biochemical characterization of terpene synthases.

    PubMed

    Vardakou, Maria; Salmon, Melissa; Faraldos, Juan A; O'Maille, Paul E

    2014-01-01

    Terpenes are the largest group of natural products with important and diverse biological roles, while of tremendous economic value as fragrances, flavours and pharmaceutical agents. Class-I terpene synthases (TPSs), the dominant type of TPS enzymes, catalyze the conversion of prenyl diphosphates to often structurally diverse bioactive terpene hydrocarbons, and inorganic pyrophosphate (PPi). To measure their kinetic properties, current bio-analytical methods typically rely on the direct detection of hydrocarbon products by radioactivity measurements or gas chromatography-mass spectrometry (GC-MS). In this study we employed an established, rapid colorimetric assay, the pyrophosphate/malachite green assay (MG), as an alternative means for the biochemical characterization of class I TPSs activity.•We describe the adaptation of the MG assay for turnover and catalytic efficiency measurements of TPSs.•We validate the method by direct comparison with established assays. The agreement of k cat/K M among methods makes this adaptation optimal for rapid evaluation of TPSs.•We demonstrate the application of the MG assay for the high-throughput screening of TPS gene libraries.

  20. Malachite green mediates homodimerization of antibody VL domains to form a fluorescent ternary complex with singular symmetric interfaces

    PubMed Central

    Szent-Gyorgyi, Chris; Stanfield, Robyn L.; Andreko, Susan; Dempsey, Alison; Ahmed, Mushtaq; Capek, Sara; Waggoner, Alan; Wilson, Ian A.; Bruchez, Marcel P.

    2013-01-01

    We report that a symmetric small molecule ligand mediates the assembly of antibody light chain variable domains (VLs) into a correspondent symmetric ternary complex with novel interfaces. The L5* Fluorogen Activating Protein (FAP) is a VL domain that binds malachite green dye (MG) to activate intense fluorescence. Crystallography of liganded L5* reveals a 2:1 protein:ligand complex with inclusive C2 symmetry, where MG is almost entirely encapsulated between an antiparallel arrangement of the two VL domains. Unliganded L5* VL domains crystallize as a similar antiparallel VL/VL homodimer. The complementarity determining regions (CDRs) are spatially oriented to form novel VL/VL and VL/ligand interfaces that tightly constrain a propeller conformer of MG. Binding equilibrium analysis suggests highly cooperative assembly to form a very stable VL/MG/VL complex, such that MG behaves as a strong chemical inducer of dimerization. Fusion of two VL domains into a single protein tightens MG binding over 1,000-fold to low picomolar affinity without altering the large binding enthalpy, suggesting that bonding interactions with ligand and restriction of domain movements make independent contributions to binding. Fluorescence activation of a symmetrical fluorogen provides a selection mechanism for the isolation and directed evolution of ternary complexes where unnatural symmetric binding interfaces are favored over canonical antibody interfaces. As exemplified by L5*, these self-reporting complexes may be useful as modulators of protein association or as high affinity protein tags and capture reagents. PMID:23978698

  1. Remarkable photo-catalytic degradation of malachite green by nickel doped bismuth selenide under visible light irradiation

    NASA Astrophysics Data System (ADS)

    Kulsi, Chiranjit; Ghosh, Amrita; Mondal, Anup; Kargupta, Kajari; Ganguly, Saibal; Banerjee, Dipali

    2017-01-01

    Bismuth selenide (Bi2Se3) and nickel (Ni) doped Bi2Se3 were prepared by a solvothermal approach to explore the photo-catalytic performance of the materials in degradation of malachite green (MG). The presence of nickel was confirmed by X-ray photoelectron spectroscopy (XPS) measurement in doped Bi2Se3. The results showed that the nickel doping played an important role in microstructure and photo-catalytic activity of the samples. Nickel doped Bi2Se3 sample exhibited higher photo-catalytic activity than that of the pure Bi2Se3 sample under visible-light irradiation. The photo-catalytic degradation followed first-order reaction kinetics. Fast degradation kinetics and complete (100% in 5 min of visible light irradiation) removal of MG was achieved by nickel doped Bi2Se3 in presence of hydrogen peroxide (H2O2) due to modification of band gap energies leading to suppression of photo-generated electron-hole recombination.

  2. Malachite green mediates homodimerization of antibody VL domains to form a fluorescent ternary complex with singular symmetric interfaces.

    PubMed

    Szent-Gyorgyi, Chris; Stanfield, Robyn L; Andreko, Susan; Dempsey, Alison; Ahmed, Mushtaq; Capek, Sarah; Waggoner, Alan S; Wilson, Ian A; Bruchez, Marcel P

    2013-11-15

    We report that a symmetric small-molecule ligand mediates the assembly of antibody light chain variable domains (VLs) into a correspondent symmetric ternary complex with novel interfaces. The L5* fluorogen activating protein is a VL domain that binds malachite green (MG) dye to activate intense fluorescence. Crystallography of liganded L5* reveals a 2:1 protein:ligand complex with inclusive C2 symmetry, where MG is almost entirely encapsulated between an antiparallel arrangement of the two VL domains. Unliganded L5* VL domains crystallize as a similar antiparallel VL/VL homodimer. The complementarity-determining regions are spatially oriented to form novel VL/VL and VL/ligand interfaces that tightly constrain a propeller conformer of MG. Binding equilibrium analysis suggests highly cooperative assembly to form a very stable VL/MG/VL complex, such that MG behaves as a strong chemical inducer of dimerization. Fusion of two VL domains into a single protein tightens MG binding over 1000-fold to low picomolar affinity without altering the large binding enthalpy, suggesting that bonding interactions with ligand and restriction of domain movements make independent contributions to binding. Fluorescence activation of a symmetrical fluorogen provides a selection mechanism for the isolation and directed evolution of ternary complexes where unnatural symmetric binding interfaces are favored over canonical antibody interfaces. As exemplified by L5*, these self-reporting complexes may be useful as modulators of protein association or as high-affinity protein tags and capture reagents.

  3. Enhancing adsorption capacity of toxic malachite green dye through chemically modified breadnut peel: equilibrium, thermodynamics, kinetics and regeneration studies.

    PubMed

    Chieng, Hei Ing; Lim, Linda B L; Priyantha, Namal

    2015-01-01

    Breadnut skin, in both its unmodified (KS) and base-modified (BM-KS) forms, was investigated for its potential use as a low-cost adsorbent for the removal of toxic dye, malachite green (MG). Characterization of the adsorbents was carried out using scanning electron microscope, X-ray fluorescence and Fourier transform infra-red spectroscopy. Batch adsorption experiments, carried out under optimized conditions, for the adsorption of MG were fitted using five isotherm models (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin and Sips) and six error functions to determine the best-fit model. The adsorption capacity was greatly enhanced when breadnut skin was chemically modified with NaOH, leading to an adsorption capacity of 353.0 mg g(-1), that was far superior to most reported adsorbents for the removal of MG. Thermodynamics studies indicated that the adsorption of MG was spontaneous on KS and BM-KS, and the reactions were endothermic and exothermic, respectively. Kinetics studies showed that both followed the pseudo-second order. Regeneration experiments on BM-KS indicated that its adsorption capacity was still maintained at>90% even after five cycles. It can be concluded that NaOH-modified breadfruit skin has great potential to be utilized in real-life application as a low-cost adsorbent for the removal of MG in wastewater treatment.

  4. Effect of COOH-functionalized SWCNT addition on the electrical and photovoltaic characteristics of Malachite Green dye based photovoltaic cells

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.; Manik, N. B.

    2014-12-01

    We report the effect of COOH-functionalized single walled carbon nanotubes (COOH-SWCNT) on the electrical and photovoltaic characteristics of Malachite Green (MG) dye based photovoltaic cells. Two different types of photovoltaic cells were prepared, one with MG dye and another by incorporating COOH-SWCNT with this dye. Cells were characterized through different electrical and photovoltaic measurements including photocurrent measurements with pulsed radiation. From the dark current—voltage (I-V) characteristic results, we observed a certain transition voltage (Vth) for both the cells beyond which the conduction mechanism of the cells change sharply. For the MG dye, Vth is 3.9 V whereas for COOH-SWCNT mixed with this dye, Vth drops to 2.7 V. The device performance improves due to the incorporation of COOH-SWCNT. The open circuit voltage and short circuit current density change from 4.2 to 97 mV and from 108 to 965 μA/cm2 respectively. Observations from photocurrent measurements show that the rate of growth and decay of the photocurrent are quite faster in the presence of COOH-SWCNT. This observation indicates a faster charge separation processes due to the incorporation of COOH-SWCNT in the MG dye cells. The high aspect ratio of COOH-SWCNT allows efficient conduction pathways for the generated charge carriers.

  5. Optimization of process variables by response surface methodology for malachite green dye removal using lime peel activated carbon

    NASA Astrophysics Data System (ADS)

    Ahmad, Mohd Azmier; Afandi, Nur Syahidah; Bello, Olugbenga Solomon

    2015-04-01

    This study investigates the adsorptive removal of malachite green (MG) dye from aqueous solutions using chemically modified lime-peel-based activated carbon (LPAC). The adsorbent prepared was characterized using FTIR, SEM, Proximate analysis and BET techniques, respectively. Central composite design (CCD) in response surface methodology (RSM) was used to optimize the adsorption process. The effects of three variables: activation temperature, activation time and chemical impregnation ratio (IR) using KOH and their effects on percentage of dye removal and LPAC yield were investigated. Based on CCD design, quadratic models and two factor interactions (2FI) were developed correlating the adsorption variables to the two responses. Analysis of variance (ANOVA) was used to judge the adequacy of the model. The optimum conditions of MG dye removal using LPAC are: activation temperature (796 °C), activation time (1.0 h) and impregnation ratio (2.6), respectively. The percentage of MG dye removal obtained was 94.68 % resulting in 17.88 % LPAC yield. The percentage of error between predicted and experimental results for the removal of MG dye is 0.4 %. Model prediction was in good agreement with experimental results and LPAC was found to be effective in removing MG dye from aqueous solution.

  6. Ultra-high adsorption capacity of zeolitic imidazole framework-67 (ZIF-67) for removal of malachite green from water.

    PubMed

    Lin, Kun-Yi Andrew; Chang, Hsuan-Ang

    2015-11-01

    Zeolitic imidazole frameworks (ZIFs), a new class of adsorbents, are proposed to adsorb Malachite Green (MG) in water. Particularly, ZIF-67 was selected owing to its stability in water and straightforward synthesis. The as-synthesized ZIF-67 was characterized and used to adsorb MG from water. Factors affecting the adsorption capacity were investigated including mixing time, temperature, the presence of salts and pH. The kinetics, adsorption isotherm and thermodynamics of the MG adsorption to ZIF-67 were also studied. The adsorption capacity of ZIF-67 for MG could be as high as 2430mgg(-1) at 20°C, which could be improved at the higher temperatures. Such an ultra-high adsorption capacity of ZIF-67 was almost 10-times of those of conventional adsorbents, including activated carbons and biopolymers. A mechanism for the high adsorption capacity was proposed and possibly attributed to the π-π stacking interaction between MG and ZIF-67. ZIF-67 also could be conveniently regenerated by washing with ethanol and the regeneration efficiency could remain 95% up to 4 cycles of the regeneration. ZIF-67 was also able to remove MG from the aquaculture wastewater, in which MG can be typically found. These features enable ZIF-67 to be one of the most effective and promising adsorbent to remove MG from water.

  7. Reusable nanosilver-coated magnetic particles for ultrasensitive SERS-based detection of malachite green in water samples.

    PubMed

    Song, Dan; Yang, Rong; Wang, Chongwen; Xiao, Rui; Long, Feng

    2016-03-11

    A novel nanosilver-deposited silica-coated Fe3O4 magnetic particle (Fe3O4@SiO2@Ag) with uniform size, good SERS activity and magnetic responsiveness was synthesized using amination polymer. The Fe3O4@SiO2@Ag magnetic particles have been successfully applied for ultrasensitive SERS detection of malachite green (MG) in water samples. The mechanism is that MG can be adsorbed on the silver surface of nanosilver-coated magnetic particles via one nitrogen atom, and the Raman signal intensity of MG is significantly enhanced by the nanosilver layer formed on the magnetic particles. The developed sensing system exhibited a sensitive response to MG in the range of 10 fM to 100 μM with a low limit of detection (LOD) 2 fM under optimal conditions. The LOD was several orders of magnitude lower than those of other methods. This SERS-based sensor showed good reproducibility and stability for MG detection. The silver-coated magnetic particles could easily be regenerated as SERS substrates only using low pH solution for multiple sensing events. The recovery of MG added to several water samples at different concentrations ranged from 90% to 110%. The proposed method facilitates the ultrasensitive analysis of dyes to satisfy the high demand for ensuring the safety of water sources.

  8. Reusable nanosilver-coated magnetic particles for ultrasensitive SERS-based detection of malachite green in water samples

    NASA Astrophysics Data System (ADS)

    Song, Dan; Yang, Rong; Wang, Chongwen; Xiao, Rui; Long, Feng

    2016-03-01

    A novel nanosilver-deposited silica-coated Fe3O4 magnetic particle (Fe3O4@SiO2@Ag) with uniform size, good SERS activity and magnetic responsiveness was synthesized using amination polymer. The Fe3O4@SiO2@Ag magnetic particles have been successfully applied for ultrasensitive SERS detection of malachite green (MG) in water samples. The mechanism is that MG can be adsorbed on the silver surface of nanosilver-coated magnetic particles via one nitrogen atom, and the Raman signal intensity of MG is significantly enhanced by the nanosilver layer formed on the magnetic particles. The developed sensing system exhibited a sensitive response to MG in the range of 10 fM to 100 μM with a low limit of detection (LOD) 2 fM under optimal conditions. The LOD was several orders of magnitude lower than those of other methods. This SERS-based sensor showed good reproducibility and stability for MG detection. The silver-coated magnetic particles could easily be regenerated as SERS substrates only using low pH solution for multiple sensing events. The recovery of MG added to several water samples at different concentrations ranged from 90% to 110%. The proposed method facilitates the ultrasensitive analysis of dyes to satisfy the high demand for ensuring the safety of water sources.

  9. Photodegradation of malachite green dye catalyzed by Keggin-type polyoxometalates under visible-light irradiation: Transition metal substituted effects

    NASA Astrophysics Data System (ADS)

    Liu, Chun-Guang; Zheng, Ting; Liu, Shuang; Zhang, Han-Yu

    2016-04-01

    In the present paper, Keggin-type polyoxometalates (POMs) (NH4)3[PW12O40] and its mono-transition-metal-substituted species (NH4)5[{PW11O39}MII(H2O)] (M = Mn, Fe, Co, Ni, Cu, Zn) have been synthesized and used as photocatalyst to activate O2 for the degradation of dye molecule under visible-light irradiation. Because of the strong adsorption on the surface of POM catalyst, malachite green (MG) molecule was employed as a molecular probe to test their photocatalytic activity. The photodegradation study shows that introduction of transition metal ion leads to an increase in the degradation of MG in the following order: Mn < Fe < Co < [PW12O40]3- < Ni < Cu < Zn, which indicates that the photocatalytic activity of these POMs is sensitive to the transition metal substituted effects. Electronic structure analysis based on the density functional theory calculations shows that a moderate decrease of oxidizing ability of POM catalyst may improve the photocatalytic activity in the degradation of dye molecule under visible-light irradiation. Meanwhile, intermediate products about the photocatalytic oxidation of MG molecule were proposed on the basis of gas chromatograph mass spectrometer analysis.

  10. Fe(III)-loaded collagen fiber as a heterogeneous catalyst for the photo-assisted decomposition of Malachite Green.

    PubMed

    Liu, Xiaohu; Tang, Rui; He, Qiang; Liao, Xuepin; Shi, Bi

    2010-02-15

    A heterogeneous catalyst for Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber and its catalytic activity for the photo-assisted decomposition of Malachite Green (MG) was investigated. The results indicated that this Fe(III)-immobilized collagen fiber (Fe-CF) can effectively catalyse the decoloration and decomposition/mineralization of MG in aqueous solution. Catalysed by Fe-CF, MG solution was completely decolorized in 30 min, while 55.0% of TOC was removed from the dye solution within 120 min in the presence of H(2)O(2) and UVA irradiation (365 nm, 10 W). Fe-CF was recycled for seven times with certain activity loss (32.6% in decoloration, 18.5% in TOC removal), and its catalytic activity can be easily recovered by re-immobilization of Fe(III). Therefore, Fe-CF could act as an efficient and cost-effective catalyst for the photo-assisted decomposition of MG, and shows potential applications in practice.

  11. Enhanced transformation of malachite green by laccase of Ganoderma lucidum in the presence of natural phenolic compounds.

    PubMed

    Murugesan, Kumarasamy; Yang, In-Hee; Kim, Young-Mo; Jeon, Jong-Rok; Chang, Yoon-Seok

    2009-02-01

    In this study, we investigated the efficacy of phenolic extract of wheat bran and lignin-related phenolic compounds as natural redox mediators on laccase-mediated transformation of malachite green (MG) using purified laccase from the white-rot fungus Ganoderma lucidum. G. lucidum laccase was able to decolorize 40.7% MG dye (at 25 mg l(-1)) after 24 h of incubation. Whereas, the addition of phenolic extract of wheat bran enhanced the decolorization significantly (p<0.001) by two- to threefold than that of purified laccase alone. Among various natural phenolic compounds, acetovanillone, p-coumaric acid, ferulic acid, syringaldehyde, and vanillin were the most efficient mediators, as effective as the synthetic mediator 1-hydroxybenzotriazole. Characterization of MG transformation products by HPLC, UV-Vis, and liquid chromatography-mass spectrometry-electrospray ionization analysis revealed that N-demethylation was the key mechanism of decolorization of MG by laccase. Growth inhibition test based on mycelial growth inhibition of white rot fungus Phanerochaete chrysosporium revealed that treatment with laccase plus natural mediators effectively reduced the growth inhibitory levels of MG than that of untreated one. Among all the tested compounds, syringaldehyde showed the highest enhanced decolorization, as a consequence reduced growth inhibition was observed in syringaldehyde-treated samples. The results of the present study revealed that the natural phenolic compounds could alternatively be used as potential redox mediators for effective laccase-mediated decolorization of MG.

  12. Photocatalytic degradation of Reactive Black 5 and Malachite Green with ZnO and lanthanum doped nanoparticles

    NASA Astrophysics Data System (ADS)

    Kaneva, N.; Bojinova, A.; Papazova, K.

    2016-02-01

    Here we report the preparation of ZnO particles with different concentrations of La3+ doping (0, 0.5 and 1 wt%) via sol-gel method. The nanoparticles are synthesized directly from Zn(CH3COO)2.2H2O in the presence of 1-propanol and triethylamine at 80°C. The conditions are optimized to obtain particles of uniform size, easy to isolate and purify. The nanoparticles are characterized by SEM, XRD and UV-Vis analysis. The photocatalytic properties of pure and La-doped ZnO are studied in the photobleaching of Malachite Green (MG) and Reactive Black 5 (RB5) dyes in aqueous solutions upon UV illumination. It is observed that the rate constant increases with the La loading up to 1 wt%. The doping helps to achieve complete mineralization of MG within a short irradiation time. 1 wt% La-doped ZnO nanoparticles show highest photocatalytic activity. The La3+ doped ZnO particles degrade faster RB5 than MG. The reason is weaker N=N bond in comparison with the C-C bond between the central carbon atom and N,N-dimethylaminobenzyl in MG. The as-prepared ZnO particles can find practical application in photocatalytic purification of textile wastewaters.

  13. A novel magnetic biochar from sewage sludge: synthesis and its application for the removal of malachite green from wastewater.

    PubMed

    Zhang, Jing; Liu, Mao; Yang, Tao; Yang, Kai; Wang, Hongyu

    2016-10-01

    In this study, a novel magnetic sludge biochar (MSBC) from sewage sludge was created by the assembly of strontium hexaferrite (SrFe12O19) onto the surface of sewage sludge biochar (SBC) under high-temperature and oxygen-free conditions. The characterization of MSBC was achieved by Fourier transform infrared spectroscopy, X-ray diffraction and vibrating sample magnetometry, and the adsorption properties of the MSBC towards malachite green (MG) from aqueous solution were systematically investigated. The influence of variables (different mass ratio of SBC and SrFe12O19, initial MG concentration, absorbent dosage, pH and contact time) was also studied in detail. The optimal adsorption amount of MG (388.65 mg MG/g) was obtained with 500 mg MG/L, 2.0 g MSBC/L for 40 min under pH of 7.0, with different mass ratios of SBC and SrFe12O19 (1:4, 1:2, 3:4 and 1:1), when the mass ratio of SBC and SrFe12O19 was 3:4 at room temperature, and the Langmuir model was more suitable than the Freundlich model for equilibrium data. Meanwhile, the kinetic models showed that the overall adsorption process was better described by a pseudo-second-order kinetic model. The results indicated that the MSBC was a novel, efficient, magnetically separable adsorbent for the removal of the dye from wastewater.

  14. Magnetic solid-phase extraction for determination of the total malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water by high-performance liquid chromatography with fluorescence detection.

    PubMed

    Zhao, Jiao; Wei, Daqiao; Yang, Yaling

    2016-06-01

    In this study, magnetic multi-walled carbon nanotube nanoparticles were synthesized and used as the adsorbent for the sums of malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water samples followed by high performance liquid chromatography with fluorescence detection. This method was based on in situ reduction of chromic malachite green, gentian violet to colorless leucomalachite green, leucogentian violet with potassium borohydride, respectively. The obtained adsorbent combines the advantages of carbon nanotubes and Fe3 O4 nanoparticles in one material for separation and preconcentration of the reductive dyes in aqueous media. The structure and properties of the prepared nanoparticles were characterized by transmission and scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The main parameters affecting the adsorption recoveries were investigated and optimized, including reducing agent concentration, type and amount of sorbent, sample pH, and eluting conditions. Under the optimum conditions, the limits of detection in this method were 0.22 and 0.09 ng/mL for malachite green and gentian violet, respectively. Product recoveries ranged from 87.0 to 92.8% with relative standard deviations from 4.6 to 5.9%. The results indicate that the sorbent is a suitable material for the removal and concentration of triphenylmethane dyes from polluted environmental samples.

  15. Treatment of ichthyophthiriasis after malachite green. II. Earth ponds at salmonid farms.

    PubMed

    Rintamäki-Kinnunen, Päivi; Rahkonen, Mika; Mykrä, Heikki; Valtonen, E Tellervo

    2005-08-09

    We tested formalin, chloramine-T-formalin and Desirox-formalin, for use against white spot disease (ichthyophthiriasis) caused by Ichthyophthirius multifiliis at 3 salmonid farms (Salmo salar and S. trutta smolt reared in earth ponds). I. multifiliis disappeared from most individuals 4 to 5 wk after the first treatment (and after the first I. multifiliis were found) with all chemicals, indicating that combinations of these chemicals, and even formalin alone, can be used to lower the parasite burden in earth ponds to such a level that no mortality occurs. This was the case when the fish were treated frequently at the beginning of the infection. Treatment can be stopped once the fish have achieved immunity to ichthyophthiriasis. The developing immunity was also revealed by the distribution of ciliates in the course of the disease. At the beginning of the infection I. multifiliis individuals were randomly distributed among the fish, but after 2 to 3 wk, when all the fish were infected, ciliates had increased in numbers and were aggregated in such a way that some fish carried quite heavy burdens. However, over 60% of the fish were free of the parasites after 4 to 5 wk, and had few or no ciliates, meaning that the distribution was even more aggregated. Sea trout had fewer parasites than salmon, and they also recovered from infection earlier even though the treatments and ponds were similar, indicating variation in resistance to I. multifiliis between fish species. It was also evident that the chemicals and their concentrations must be planned carefully to suit the conditions at each farm.

  16. Degradation and detoxification of the triphenylmethane dye malachite green catalyzed by crude manganese peroxidase from Irpex lacteus F17.

    PubMed

    Yang, Xueting; Zheng, Jinzhao; Lu, Yongming; Jia, Rong

    2016-05-01

    Malachite green (MG), a recalcitrant, carcinogenic, and mutagenic triphenylmethane dye, was decolorized and detoxified using crude manganese peroxidase (MnP) prepared from the white rot fungus Irpex lacteus F17. In this study, the key factors (pH, temperature, MG, Mn(2+), H2O2, MnP) in these processes were investigated. Under optimal conditions, 96 % of 200 mg L(-1) of MG was decolorized when 66.32 U L(-1) of MnP was added for 1 h. The K m, V max, and k cat values were 109.9 μmol L(-1), 152.8 μmol L(-1) min(-1), and 44.5 s(-1), respectively. The decolorization of MG by MnP followed first-order reaction kinetics with a kinetic rate constant of 0.0129 h(-1). UV-vis and UPLC analysis revealed degradation of MG. Furthermore, seven different intermediates formed during the MnP treatment of 0.5 h were identified by LC-TOF-MS. These degradation products were generated via two different routes by either N-demethylation of MG or the oxidative cleavage of the C-C double bond in MG. Based on ecotoxicity analyses performed on bacteria and algae, it was confirmed that MG metabolites produced by the MnP-catalyzed system were appreciably less toxic than the parent compound. These studies indicate the potential use of this enzyme system in the clean-up of aquatic and terrestrial environments.

  17. Design of binary SnO2-CuO nanocomposite for efficient photocatalytic degradation of malachite green dye

    NASA Astrophysics Data System (ADS)

    Kumar, Aniket; Rout, Lipeeka; Achary, L. Satish Kumar; Mohanty, Anurag; Marpally, Jyoshna; Chand, Pradyumna Kumar; Dash, Priyabrat

    2016-04-01

    Semiconductor mediated photocatalysis has got enormous consideration as it has shown immense potential in addressing the overall energy and environmental issues. To overcome the earlier drawbacks concerning quick charge recombination and limited visible-light absorption of semiconductor photocatalysts, numerous methods have been produced in the past couple of decades and the most broadly utilized one is to develop the photocatalytic heterojunctions. In our work, a series of SnO2-CuO nanocomposites of different compositions were synthesized by a combustion method and have been investigated in detail by various characterization techniques, such as wide angle X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The results revealed that the crystal structure and optical properties of the nanocomposites were almost same for all the compositions. FE-SEM images showed that the shape of SnO2-CuO was spherical in nature and the 1: 1 Sn/Cu sample had a well-proportioned morphology. The malachite green dye was used for the photocatalytic studies in a photoreactor and monitored with a UV-visible spectrometer for different composition ratio of metal (Sn: Cu) such as 1:1, 1:2, 2:1, 1:0.5 and 0.5:1. The 1:1 ratio nanocomposite showed excellent photocatalytic degradation of 96 % compared to pure SnO2 and CuO. The mechanism of degradation and charge separation ability of the nanocomposite are also explored using photocurrent measurement study.

  18. Fast removal of malachite green dye using novel superparamagnetic sodium alginate-coated Fe3O4 nanoparticles.

    PubMed

    Mohammadi, Abbas; Daemi, Hamed; Barikani, Mehdi

    2014-08-01

    In this study, superparamagnetic sodium alginate-coated Fe3O4 nanoparticles (Alg-Fe3O4) as a novel magnetic adsorbent were prepared by in situ coprecipitation method, in which Fe3O4 nanoparticles were precipitated from FeCl3 and FeCl2 under alkaline medium in the presence of sodium alginate. The Alg-Fe3O4 nanoparticles were used for removal of malachite green (MG) from aqueous solutions using batch adsorption technique. The characterization of synthesized nanoparticles was performed using XRD, FTIR, TEM, TGA and vibrating sample magnetometer (VSM) techniques. FTIR analysis of synthesized nanoparticles provided the evidence that sodium alginate was successfully coated on the surface of Fe3O4 nanoparticles. The FT-IR and TGA characterization showed that the Alg-Fe3O4 nanoparticles contained about 14% (w/w) of sodium alginate. Moreover, TEM analysis indicated that the average diameter of the Alg-Fe3O4 nanoparticles was about 12nm. The effects of adsorbent dosage, pH and temperature were investigated on the adsorption properties of MG onto Alg-Fe3O4 nanoparticles. The equilibrium adsorption data were modeled using the Langmuir and Freundlich isotherms. The maximum adsorption capacity obtained from Langmuir isotherm equation was 47.84mg/g. The kinetics of adsorption of MG onto Alg-Fe3O4 nanoparticles were investigated using the pseudo-first-order and pseudo-second-order kinetic models. The results showed that the adsorption of MG onto nanoparticles followed pseudo-second-order kinetic model.

  19. Molecular cloning, characterization and expression of heat shock protein 70 gene from the oyster Crassostrea hongkongensis responding to thermal stress and exposure of Cu(2+) and malachite green.

    PubMed

    Zhang, Zhanhui; Zhang, Qizhong

    2012-04-15

    Heat shock protein 70 (HSP70) acts mostly as a molecular chaperone and plays a key role in the process of protecting cells by facilitating the folding of nascent peptides and the cellular stress response. The cDNA of the oyster Crassostrea hongkongensis hsp70 (designated chhsp70) was cloned with the techniques of homological cloning and rapid amplification of cDNA ends (RACE). The full-length chhsp70 cDNA was 2251bp, consisting of a 130bp 5'-UTR, 216bp 3'-UTR with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 1905bp, which encoded a polypeptide of 634 amino acids. Three classical HSP signature motifs were detected in ChHSP70, i.e., DLGTT-S-V, IFDLGGGTFDVSIL and VVLVGGSTRIPKIQK. BLAST analysis revealed that the ChHSP70 shared high identity with other bivalve HSP70. The phylogenetic analysis indicated that the ChHSP70 was a member of the HSP70 family. The chhsp70 mRNA transcripts were quantified by fluorescent real time RT-PCR under both unstressed and stressed conditions, i. e., heat shock and exposure to Cu(2+) and malachite green. Basal expression level was similar in mantle, gill, digestive gland, and heart, but higher in muscle than that in the others. A similar trend showed that the chhsp70 mRNA expression significantly increased at 3-6h, then dropped and returned to control level at 24h in the five tissues and organs mentioned above after heat shock. A clearly time-dependent expression pattern of chhsp70 mRNA in digestive gland and gill of the oyster was observed after exposure of Cu(2+) and malachite green. In the two tissues, the chhsp70 mRNA level reached the maximum at 6h after malachite green exposure and on day 4 after Cu(2+) exposure, and then decreased progressively to the control level. The results indicated that ChHSP70 of the oyster is an inducible protein, and plays an important role in response to the Cu(2+) and malachite green polluted stress, so chhsp70 might be used as a potential molecular

  20. Application of Micro-cloud point extraction for spectrophotometric determination of Malachite green, Crystal violet and Rhodamine B in aqueous samples

    NASA Astrophysics Data System (ADS)

    Ghasemi, Elham; Kaykhaii, Massoud

    2016-07-01

    A novel, green, simple and fast method was developed for spectrophotometric determination of Malachite green, Crystal violet, and Rhodamine B in water samples based on Micro-cloud Point extraction (MCPE) at room temperature. This is the first report on the application of MCPE on dyes. In this method, to reach the cloud point at room temperature, the MCPE procedure was carried out in brine using Triton X-114 as a non-ionic surfactant. The factors influencing the extraction efficiency were investigated and optimized. Under the optimized condition, calibration curves were found to be linear in the concentration range of 0.06-0.60 mg/L, 0.10-0.80 mg/L, and 0.03-0.30 mg/L with the enrichment factors of 29.26, 85.47 and 28.36, respectively for Malachite green, Crystal violet, and Rhodamine B. Limit of detections were between 2.2 and 5.1 μg/L.

  1. Application of Micro-cloud point extraction for spectrophotometric determination of Malachite green, Crystal violet and Rhodamine B in aqueous samples.

    PubMed

    Ghasemi, Elham; Kaykhaii, Massoud

    2016-07-05

    A novel, green, simple and fast method was developed for spectrophotometric determination of Malachite green, Crystal violet, and Rhodamine B in water samples based on Micro-cloud Point extraction (MCPE) at room temperature. This is the first report on the application of MCPE on dyes. In this method, to reach the cloud point at room temperature, the MCPE procedure was carried out in brine using Triton X-114 as a non-ionic surfactant. The factors influencing the extraction efficiency were investigated and optimized. Under the optimized condition, calibration curves were found to be linear in the concentration range of 0.06-0.60mg/L, 0.10-0.80mg/L, and 0.03-0.30mg/L with the enrichment factors of 29.26, 85.47 and 28.36, respectively for Malachite green, Crystal violet, and Rhodamine B. Limit of detections were between 2.2 and 5.1μg/L.

  2. Biodegradation of malachite green by strain Pseudomonas sp. K9 and cloning of the tmr2 gene associated with an ISPpu12.

    PubMed

    Huan-Mei; Lian-Tai, Li; Cai-Fang, Yan; Jin-Jin, Sun; Yuan-Gao; Hong, Qing; Shun-Peng, Li

    2011-06-01

    A bacterial strain K9 capable of degrading malachite green was isolated from the sludge of the wastewater treatment system of a chemical plant. It was identified preliminarily as Pseudomonas sp. Strain K9 was also able to degrade other triphenylmethane dyes, such as Crystal Violet and Basic Fuchsin. The gene tmr2, encoding the triphenylmethane reductase, was cloned from strain K9, and functionally expressed in E. coli. A 5946-bp DNA fragment including the tmr2 gene was cloned from the genomic DNA of strain K9 by chromosome walking. Its sequence analysis showed that tmr2 was associated with a typical mobile element ISPpu12 consisting of tnpA (encoding a transposase), lspA (encoding a lipoprotein signal peptidase) and orf1 (encoding a putative MerR family regulator), orf2 (encoding a CDF family heavy metal/H(+) antiporter). This association was also found in another malachite green-degrading strain Pseudomonas sp. MDB-1, which indicated that the tmr2 gene might be a horizontally transferable gene.

  3. Photocatalytic performance of Sn-doped TiO{sub 2} nanostructured thin films for photocatalytic degradation of malachite green dye under UV and VIS-lights

    SciTech Connect

    Sayilkan, F.; Asiltuerk, M.; Tatar, P.; Kiraz, N.; Sener, S.; Arpac, E.; Sayilkan, H.

    2008-01-08

    Sn-doped and undoped nano-TiO{sub 2} particles have been synthesized by hydrotermal process without acid catalyst at 225 deg. C in 1 h. Nanostructure-TiO{sub 2} based thin films, contain at different solid ratio of TiO{sub 2} in coating, have been prepared on glass surfaces by spin-coating technique. The structure, surface morphology and optical properties of the thin films and the particles have been investigated by element analysis and XRD, BET and UV/VIS/NIR techniques. The photocatalytic performance of the films was tested for degradation of malachite green dye in solution under UV and VIS-lights. The results showed that the hydrothermally synthesized nano-TiO{sub 2} particles are fully anatase crystalline form and are easily dispersed in water, the coated surfaces have nearly super-hydrophilic properties and, the doping of transition metal ion efficiently improved the photocatalytic performance of the TiO{sub 2} thin film. The results also proved that malachite green is decomposed catalytically due to the pseudo first-order reaction kinetics.

  4. Comparison of the photodynamic fungicidal efficacy of methylene blue, toluidine blue, malachite green and low-power laser irradiation alone against Candida albicans.

    PubMed

    Souza, Rodrigo C; Junqueira, Juliana Campos; Rossoni, Rodnei D; Pereira, Cristiane A; Munin, Egberto; Jorge, Antonio O C

    2010-05-01

    This study was to evaluate specific effects of photodynamic therapy (energy density 15.8 J/cm(2), 26.3 J/cm(2) and 39.5 J/cm(2)) using methylene blue, toluidine blue and malachite green as photosensitizers and low-power laser irradiation on the viability of Candida albicans. Suspensions of C. albicans containing 10(6) cells/ml were standardized in a spectrophotometer. For each dye, 120 assays, divided into four groups according to the following experimental conditions, were carried out: laser irradiation in the presence of the photosensitizer; laser irradiation only; treatment with the photosensitizer only; no exposure to laser light or photosensitizer. Next, serial dilutions were prepared and seeded onto Sabouraud dextrose agar for the determination of the number of colony-forming units per milliliter (CFU/ml). The results were subjected to analysis of variance and the Tukey test (P < 0.05). Photodynamic therapy using the photosensitizers tested was effective in reducing the number of C. albicans.. The number of CFU/ml was reduced by between 0.54 log(10) and 3.07 log(10) and depended on the laser energy density used. Toluidine blue, methylene blue and malachite green were effective photosensitizers in antimicrobial photodynamic therapy against C. albicans, as was low-power laser irradiation alone.

  5. Surfactant-free synthesis of octahedral ZnO/ZnFe2O4 heterostructure with ultrahigh and selective adsorption capacity of malachite green

    NASA Astrophysics Data System (ADS)

    Liu, Jue; Zeng, Min; Yu, Ronghai

    2016-05-01

    A new octahedral ZnO/ZnFe2O4 heterostructure has been fabricated through a facile surfactant-free solvothermal method followed by thermal treatment. It exhibits a record-high adsorption capacity (up to 4983.0 mg·g‑1) of malachite green (MG), which is a potentially harmful dye in prevalence and should be removed from wastewater and other aqueous solutions before discharging into the environment. The octahedral ZnO/ZnFe2O4 heterostructure also demonstrates strong selective adsorption towards MG from two kinds of mixed solutions: MG/methyl orange (MO) and MG/rhodamine B (RhB) mixtures, indicating its promise in water treatment.

  6. Photo-triggered release from liposomes without membrane solubilization, based on binding to poly(vinyl alcohol) carrying a malachite green moiety.

    PubMed

    Uda, Ryoko M; Kato, Yutaka; Takei, Michiko

    2016-10-01

    When working with liposomes analogous to cell membranes, it is important to develop substrates that can regulate interactions with the liposome surface in response to light. We achieved a photo-triggered release from liposomes by using a copolymer of poly(vinyl alcohol) carrying a malachite green moiety (PVAMG). Although PVAMG is a neutral polymer under dark conditions, it is photoionized upon exposure to UV light, resulting in the formation of a cationic site for binding to liposomes with a negatively charged surface. Under UV irradiation, PVAMG showed effective interaction with liposomes, releasing the encapsulated compound; however, this release was negligible under dark conditions. The poly(vinyl alcohol) moiety of PVAMG played an important role in the photo-triggered release. This release was caused by membrane destabilization without lipid solubilization. We also investigated different aspects of liposome/PVAMG interactions, including PVAMG-induced fusion between the liposomes and the change in the liposome morphologies.

  7. Surfactant-free synthesis of octahedral ZnO/ZnFe2O4 heterostructure with ultrahigh and selective adsorption capacity of malachite green

    PubMed Central

    Liu, Jue; Zeng, Min; Yu, Ronghai

    2016-01-01

    A new octahedral ZnO/ZnFe2O4 heterostructure has been fabricated through a facile surfactant-free solvothermal method followed by thermal treatment. It exhibits a record-high adsorption capacity (up to 4983.0 mg·g−1) of malachite green (MG), which is a potentially harmful dye in prevalence and should be removed from wastewater and other aqueous solutions before discharging into the environment. The octahedral ZnO/ZnFe2O4 heterostructure also demonstrates strong selective adsorption towards MG from two kinds of mixed solutions: MG/methyl orange (MO) and MG/rhodamine B (RhB) mixtures, indicating its promise in water treatment. PMID:27142194

  8. Compression mechanism of subpicosecond pulses by malachite green dye in passively mode-locked rhodamine 6G/DODCI CW dye lasers

    SciTech Connect

    Watanabe, A.; Hara, M.; Kobayashi, H.; Takemura, H.; Tanaka, S.

    1983-04-01

    The pulse width compression effect of a malachite green (MG) dye upon subpicosecond pulses has been experimentally investigated in a CW passively mode-locked rhodamine 6G/DODCI dye laser. The pulse width reduces as MG concentration increases, and reaches 0.34 ps at 1.5 X 10/sup -6/ M. By adding the MG dye, good mode locking is achieved in a rather wide pumping-power range. A computer simulation of pulse growth has also been carried out by using simple rate equations, in which the fast-recovery component of loss due to the MG dye is taken into account. The simulated results can explain some experimental results qualitatively such as pulse width compression and pumping-power restriction. The pulse width compression results essentially from the fast recovery of cavity loss caused by the MG dye.

  9. Central composite design and genetic algorithm applied for the optimization of ultrasonic-assisted removal of malachite green by ZnO Nanorod-loaded activated carbon.

    PubMed

    Ghaedi, M; Azad, F Nasiri; Dashtian, K; Hajati, S; Goudarzi, A; Soylak, M

    2016-10-05

    Maximum malachite green (MG) adsorption onto ZnO Nanorod-loaded activated carbon (ZnO-NR-AC) was achieved following the optimization of conditions, while the mass transfer was accelerated by ultrasonic. The central composite design (CCD) and genetic algorithm (GA) were used to estimate the effect of individual variables and their mutual interactions on the MG adsorption as response and to optimize the adsorption process. The ZnO-NR-AC surface morphology and its properties were identified via FESEM, XRD and FTIR. The adsorption equilibrium isotherm and kinetic models investigation revealed the well fit of the experimental data to Langmuir isotherm and pseudo-second-order kinetic model, respectively. It was shown that a small amount of ZnO-NR-AC (with adsorption capacity of 20mgg(-1)) is sufficient for the rapid removal of high amount of MG dye in short time (3.99min).

  10. Central composite design and genetic algorithm applied for the optimization of ultrasonic-assisted removal of malachite green by ZnO Nanorod-loaded activated carbon

    NASA Astrophysics Data System (ADS)

    Ghaedi, M.; Azad, F. Nasiri; Dashtian, K.; Hajati, S.; Goudarzi, A.; Soylak, M.

    2016-10-01

    Maximum malachite green (MG) adsorption onto ZnO Nanorod-loaded activated carbon (ZnO-NR-AC) was achieved following the optimization of conditions, while the mass transfer was accelerated by ultrasonic. The central composite design (CCD) and genetic algorithm (GA) were used to estimate the effect of individual variables and their mutual interactions on the MG adsorption as response and to optimize the adsorption process. The ZnO-NR-AC surface morphology and its properties were identified via FESEM, XRD and FTIR. The adsorption equilibrium isotherm and kinetic models investigation revealed the well fit of the experimental data to Langmuir isotherm and pseudo-second-order kinetic model, respectively. It was shown that a small amount of ZnO-NR-AC (with adsorption capacity of 20 mg g- 1) is sufficient for the rapid removal of high amount of MG dye in short time (3.99 min).

  11. Isotherm and kinetics study of malachite green adsorption onto copper nanowires loaded on activated carbon: artificial neural network modeling and genetic algorithm optimization.

    PubMed

    Ghaedi, M; Shojaeipour, E; Ghaedi, A M; Sahraei, Reza

    2015-05-05

    In this study, copper nanowires loaded on activated carbon (Cu-NWs-AC) was used as novel efficient adsorbent for the removal of malachite green (MG) from aqueous solution. This new material was synthesized through simple protocol and its surface properties such as surface area, pore volume and functional groups were characterized with different techniques such XRD, BET and FESEM analysis. The relation between removal percentages with variables such as solution pH, adsorbent dosage (0.005, 0.01, 0.015, 0.02 and 0.1g), contact time (1-40min) and initial MG concentration (5, 10, 20, 70 and 100mg/L) was investigated and optimized. A three-layer artificial neural network (ANN) model was utilized to predict the malachite green dye removal (%) by Cu-NWs-AC following conduction of 248 experiments. When the training of the ANN was performed, the parameters of ANN model were as follows: linear transfer function (purelin) at output layer, Levenberg-Marquardt algorithm (LMA), and a tangent sigmoid transfer function (tansig) at the hidden layer with 11 neurons. The minimum mean squared error (MSE) of 0.0017 and coefficient of determination (R(2)) of 0.9658 were found for prediction and modeling of dye removal using testing data set. A good agreement between experimental data and predicted data using the ANN model was obtained. Fitting the experimental data on previously optimized condition confirm the suitability of Langmuir isotherm models for their explanation with maximum adsorption capacity of 434.8mg/g at 25°C. Kinetic studies at various adsorbent mass and initial MG concentration show that the MG maximum removal percentage was achieved within 20min. The adsorption of MG follows the pseudo-second-order with a combination of intraparticle diffusion model.

  12. Isotherm and kinetics study of malachite green adsorption onto copper nanowires loaded on activated carbon: Artificial neural network modeling and genetic algorithm optimization

    NASA Astrophysics Data System (ADS)

    Ghaedi, M.; Shojaeipour, E.; Ghaedi, A. M.; Sahraei, Reza

    2015-05-01

    In this study, copper nanowires loaded on activated carbon (Cu-NWs-AC) was used as novel efficient adsorbent for the removal of malachite green (MG) from aqueous solution. This new material was synthesized through simple protocol and its surface properties such as surface area, pore volume and functional groups were characterized with different techniques such XRD, BET and FESEM analysis. The relation between removal percentages with variables such as solution pH, adsorbent dosage (0.005, 0.01, 0.015, 0.02 and 0.1 g), contact time (1-40 min) and initial MG concentration (5, 10, 20, 70 and 100 mg/L) was investigated and optimized. A three-layer artificial neural network (ANN) model was utilized to predict the malachite green dye removal (%) by Cu-NWs-AC following conduction of 248 experiments. When the training of the ANN was performed, the parameters of ANN model were as follows: linear transfer function (purelin) at output layer, Levenberg-Marquardt algorithm (LMA), and a tangent sigmoid transfer function (tansig) at the hidden layer with 11 neurons. The minimum mean squared error (MSE) of 0.0017 and coefficient of determination (R2) of 0.9658 were found for prediction and modeling of dye removal using testing data set. A good agreement between experimental data and predicted data using the ANN model was obtained. Fitting the experimental data on previously optimized condition confirm the suitability of Langmuir isotherm models for their explanation with maximum adsorption capacity of 434.8 mg/g at 25 °C. Kinetic studies at various adsorbent mass and initial MG concentration show that the MG maximum removal percentage was achieved within 20 min. The adsorption of MG follows the pseudo-second-order with a combination of intraparticle diffusion model.

  13. A chemometric-assisted method for the simultaneous determination of malachite green and crystal violet in water based on absorbance-pH data generated by a homemade pH gradient apparatus.

    PubMed

    Yu, Shuling; Yuan, Xuejie; Yang, Jing; Yuan, Jintao; Shi, Jiahua; Wang, Yali; Chen, Yuewen; Gao, Shufang

    2015-01-01

    An attractive method of generating second-order data was developed by a dropping technique to generate pH gradient simultaneously coupled with diode-array spectrophotometer scanning. A homemade apparatus designed for the pH gradient. The method and the homemade apparatus were used to simultaneously determine malachite green (MG) and crystal violet (CV) in water samples. The absorbance-pH second-order data of MG or CV were obtained from the spectra of MG or CV in a series of pH values of HCl-KCl solution. The second-order data of mixtures containing MG and CV that coexisted with interferents were analyzed using multidimensional partial least-squares with residual bilinearization. The method and homemade apparatus were used to simultaneously determine MG and CV in fish farming water samples and in river ones with satisfactory results. The presented method and the homemade apparatus could serve as an alternative tool to handle some analysis problems.

  14. Purification and characterization of a temperature- and pH-stable laccase from the spores of Bacillus vallismortis fmb-103 and its application in the degradation of malachite green.

    PubMed

    Zhang, Chong; Zhang, Shuang; Diao, Hanwen; Zhao, Haizhen; Zhu, Xiaoyu; Lu, Fengxia; Lu, Zhaoxin

    2013-06-12

    Malachite green residue can affect aquaculture food safety. Bioremediation of contaminated water by enzyme treatment is an environmentally friendly and economical way to remove contaminating substances. In the present study, a temperature- and pH-stable laccase was purified from the spores of Bacillus ballismortis fmb-103 and was used to degrade malachite green. The laccase from fmb-103 (fmb-L103) was purified 15.2-fold to homogeneity (389.9 mU/mg protein with respect to ABTS as a substrate) by precipitation with 30-80% (NH4)2SO4, DEAE-Sephadex A-50 ion exchange chromatography, and Sephadex G-100 chromatography. fmb-L103 is a nonblue laccase with a molecular weight of 55.0 kDa and Cu content of 2.5 (mol:mol). fmb-L103 retained more than 50% activity after 10 h at 70 °C and demonstrated broad pH stability in both acidic and alkaline conditions. The effects of inhibitors and metal ions on fmb-L103 activity were also examined. A kinetic study revealed that ABTS was a suitable substrate with a Km of 22.7 μmol and a Vmax of 3.32 μmol/mL/min. fmb-L103 can efficiently degrade malachite green after a 48 h treatment period in combination with a mediator, without the appearance of leucomalachite green.

  15. [Simultaneous determination of residues of malachite green, crystal violet and their leuco metabolites in aquatic products by liquid chromatography-tandem mass spectrometry].

    PubMed

    Zhu, Kuanzheng; Wang, Peng; Lin, Yanfei; Xiao, Songjian; Mei, Surong

    2007-01-01

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of the residues of malachite green (MG), eucomalachite green (LMG), crystal violet (CV) and leucocrystal violet (LCV) in aquatic products. The target analytes were extracted from homogenized samples with a mixture of acetonitrile and ammonium acetate buffer, partitioned against methylene chloride, and purified on tandem neutral alumina and PRS solid-phase extraction (SPE) cartridges. Chromatographic separation was achieved by using a ZORBAX SB-C18 column with an isocratic mobile phase consisting of ammonium acetate (0.5 mmol/L) and acetonitrile (10: 90, v/v) without on-line post-column oxidation with PbO2 which had been widely used in the previous methods. Identification and quantification were performed using multiple reaction monitoring (MRM) with one precursor ion, and two product ions for each analyte and electrospray ionization in positive mode. The limits of detection were 0.5 ng/g. The recoveries were in the range of 77.6% - 98.1%, and the relative standard deviations were less than 8.2%. The results showed that the method is suitable for the determination of residues of MG, LMG, CV and LCV in aquatic products.

  16. Co-immobilization of laccase and mediator through a self-initiated one-pot process for enhanced conversion of malachite green.

    PubMed

    Sun, Hongfei; Huang, Wenguang; Yang, Hua; Zhang, Shujuan

    2016-06-01

    Laccase is a green biocatalyst. It works with molecular oxygen and produces water as the only by-product. However, its practical application is far less than satisfactory due to the low stability/poor reusability of free laccase and the potential secondary pollution caused by dissolved mediators. To address those bottlenecks in laccase-based catalysis, a novel biocatalyst (Immo-LMS) was fabricated by simultaneously immobilizing both laccase and a mediator (acetylacetone, abbreviated as AA) into a hydrogel through the laccase-AA initiated polymerization. This self-initiated immobilization process avoided the forced conformational change of laccase in the passive embedding to pre-existing carriers. Resulting from the effective cooperation of laccase and AA, the Immo-LMS had the highest substrate conversion quantity to malachite green, followed by the sole immobilized laccase and the immobilized laccase with an external mediator. Besides the improved activity, the Immo-LMS showed enhanced stability. The good performance of the Immo-LMS suggests that the co-immobilization of laccase and mediator through the self-initiated one-pot process was a promising strategy for the immobilization of laccase, which is expected to be helpful to cut down the running cost as well as the potential toxicity that come from mediators in the practical application of laccase.

  17. Simultaneous determination of malachite green, gentian violet and their leuco-metabolites in aquatic products by high-performance liquid chromatography-linear ion trap mass spectrometry.

    PubMed

    Wu, Xueli; Zhang, Gong; Wu, Yongning; Hou, Xiaolin; Yuan, Zonghui

    2007-11-23

    A method has been developed for the simultaneous determination of malachite green, gentian violet and their leuco-metabolites in various aquatic products using isotope dilution liquid chromatography-linear ion trap mass spectrometry without post-column oxidation. Sample was extracted with McIlvaine buffer and acetonitrile, followed by partitioning with dichloromethane, purified on basic alumina and OASIS MCX SPE column, and finally analyzed by LC-ESI-MS/MS with the select reaction monitoring (SRM) mode. Decision limits (CCalpha, alpha=0.01) and detection capability (CCbeta, beta=0.05) of the method were in the range of 0.02-0.09 and 0.04-0.13microg/kg for MG, GV, LMG and LGV in grass carp, eel, salmon, shrimp and shellfish, respectively, recoveries of MG, GV, LMG and LGV at all fortification levels (0.25-10microg/kg) were from 80.8% to 115.7%, inter-day relative standard derivations were from 1.9% to 18.4%. This method appeared suitable for the control of MG, GV, LMG and LGV residues in aquatic products.

  18. Manganese peroxidase h4 isozyme mediated degradation and detoxification of triarylmethane dye malachite green: optimization of decolorization by response surface methodology.

    PubMed

    Saravanakumar, Thiyagarajan; Palvannan, Thayumanavan; Kim, Dae-Hyuk; Park, Seung-Moon

    2013-11-01

    A cDNA encoding for manganese peroxidase isozyme H4 (MnPH4), isolated from Phanerochaete chrysosporium, was expressed in Pichia pastoris, under the control of alcohol oxidase I promoter. The recombinant MnPH4 was efficiently secreted onto media supplemented with hemin at a maximum concentration of 500 U/L, after which purified rMnPH4 was used to decolorize the triarylmethane dye malachite green (MG). Response surface methodology (RSM) was employed to optimize three different operational parameters for the decolorization of MG. RSM showed that the optimized variables of enzyme (0.662 U), MnSO4 (448 μM), and hydrogen peroxide (159 μM) decolorized 100 mg/L of MG completely at 3 h. Additionally, UV-VIS spectra, high-performance liquid chromatography, gas chromatography-mass spectrometry, and liquid chromatography-electrospray ionization/mass spectrometry analysis confirmed the degradation of MG by the formation of main metabolites 4-dimethylamino-benzophenone hydrate, N, N-dimethylaniline (N,N-dimethyl-benzenamine), and methylbenzaldehyde. Interestingly, it was found that rMnPH4 mediates hydroxyl radical attack on the central carbon of MG. Finally, rMnPH4 degraded MG resulted in the complete removal of its toxicity, which was checked under in vitro conditions.

  19. A hybrid model of support vector regression with genetic algorithm for forecasting adsorption of malachite green onto multi-walled carbon nanotubes: central composite design optimization.

    PubMed

    Ghaedi, M; Dashtian, K; Ghaedi, A M; Dehghanian, N

    2016-05-11

    The aim of this work is the study of the predictive ability of a hybrid model of support vector regression with genetic algorithm optimization (GA-SVR) for the adsorption of malachite green (MG) onto multi-walled carbon nanotubes (MWCNTs). Various factors were investigated by central composite design and optimum conditions was set as: pH 8, 0.018 g MWCNTs, 8 mg L(-1) dye mixed with 50 mL solution thoroughly for 10 min. The Langmuir, Freundlich, Temkin and D-R isothermal models are applied to fitting the experimental data, and the data was well explained by the Langmuir model with a maximum adsorption capacity of 62.11-80.64 mg g(-1) in a short time at 25 °C. Kinetic studies at various adsorbent dosages and the initial MG concentration show that maximum MG removal was achieved within 10 min of the start of every experiment under most conditions. The adsorption obeys the pseudo-second-order rate equation in addition to the intraparticle diffusion model. The optimal parameters (C of 0.2509, σ(2) of 0.1288 and ε of 0.2018) for the SVR model were obtained based on the GA. For the testing data set, MSE values of 0.0034 and the coefficient of determination (R(2)) values of 0.9195 were achieved.

  20. A versatile SERS-based immunoassay for immunoglobulin detection using antigen-coated gold nanoparticles and malachite green-conjugated protein A/G.

    PubMed

    Neng, Jing; Harpster, Mark H; Zhang, Hao; Mecham, James O; Wilson, William C; Johnson, Patrick A

    2010-11-15

    A surface enhanced Raman scattering (SERS) immunoassay for antibody detection in serum is described in the present work. The developed assay is conducted in solution and utilizes Au nanoparticles coated with the envelope (E) protein of West Nile Virus (WNV) as the SERS-active substrate and malachite green (MG)-conjugated protein A/G (MG-pA/G) as a bi-functional Raman tag/antibody binding reporter. Upon incubation of these reagents with serum collected from rabbits inoculated with E antigen, laser interrogation of the sandwiched immunocomplex revealed a SERS signaling response diagnostic for MG. The intensification of signature spectral peaks is shown to be proportionate to the concentration of added serum and the limit of antibody detection is 2 ng/ml of serum. To assess assay performance relative to more a traditional immunoassay, indirect enzyme-linked immunosorbent assays conducted using the same concentrations of reagents were found to be >400-fold less sensitive. Quartz crystal microbalance with dissipation (QCM-D) monitoring of immunocomplex film deposition on solid Au surfaces also confirmed the formation of antigen-antibody-protein A/G trilayers and provided quantitative measurements of film thickness which likely position MG within the sensing distance of laser-elicited, enhanced electromagnetic fields. The sensitivity and inherent versatility of the assay, which is provided by the binding of pA/G to a broad spectrum of immunoglobulins in different mammalian species, suggest that it could be developed as an alternative immunoassay format to the ELISA.

  1. A rapid molecular diagnosis of cutaneous leishmaniasis by colorimetric malachite green-loop-mediated isothermal amplification (LAMP) combined with an FTA card as a direct sampling tool.

    PubMed

    Nzelu, Chukwunonso O; Cáceres, Abraham G; Guerrero-Quincho, Silvia; Tineo-Villafuerte, Edwin; Rodriquez-Delfin, Luis; Mimori, Tatsuyuki; Uezato, Hiroshi; Katakura, Ken; Gomez, Eduardo A; Guevara, Angel G; Hashiguchi, Yoshihisa; Kato, Hirotomo

    2016-01-01

    Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64°C for 60min using a heating block and/or water bath and DNA amplification was detected immediately after incubation. The LAMP assay had high detection sensitivity down to a level of 0.01 parasites per μl. The field- and clinic-applicability of the colorimetric FTA-LAMP assay was demonstrated with 122 clinical samples collected from patients suspected of having cutaneous leishmaniasis in Peru, from which 71 positives were detected. The LAMP assay in combination with an FTA card described here is rapid and sensitive, as well as simple to perform, and has great potential usefulness for diagnosis and surveillance of leishmaniasis in endemic areas.

  2. Photocatalytic performance of Sn-doped TiO2 nanostructured mono and double layer thin films for Malachite Green dye degradation under UV and vis-lights.

    PubMed

    Sayilkan, F; Asiltürk, M; Tatar, P; Kiraz, N; Arpaç, E; Sayilkan, H

    2007-06-01

    Nanostructure Sn(4+)-doped TiO(2) based mono and double layer thin films, contain 50% solid ratio of TiO(2) in coating have been prepared on glass surfaces by spin-coating technique. Their photocatalytic performances were tested for degradation of Malachite Green dye in solution under UV and vis irradiation. Sn(4+)-doped nano-TiO(2) particle a doping ratio of about 5[Sn(4+)/Ti(OBu(n))(4); mol/mol%] has been synthesized by hydrotermal process at 225 degrees C. The structure, surface and optical properties of the thin films and/or the particles have been investigated by XRD, BET and UV/vis/NIR techniques. The results showed that the double layer coated glass surfaces have a very high photocatalytic performance than the other one under UV and vis lights. The results also proved that the hydrothermally synthesized nano-TiO(2) particles are fully anatase crystalline form and are easily dispersed in water. The results also reveal that the coated surfaces have hydrophilic property.

  3. Equilibrium uptake, sorption dynamics, process optimization, and column operations for the removal and recovery of malachite green from wastewater using activated carbon and activated slag

    SciTech Connect

    Gupta, V.K.; Srivastava, S.K.; Mohan, D.

    1997-06-01

    The waste slurry generated in fertilizer plants and slag (blast furnace waste) have been converted into low-cost adsorbents, activated carbon and activated slag, respectively, and these are utilized for the removal of malachite green (a basic dye) from wastewater. In the batch experiments, parameters studied include the effect of pH, sorbent dosage, adsorbate concentration, temperature, and contact time. Kinetic studies have been performed to have an idea of the mechanistic aspects and to obtain the thermodynamic parameters of the process. The uptake of the dye is greater on carbonaceous material than on activated slag. Sorption data have been correlated with both Langmuir and Freundlich adsorption models. The presence of anionic surfactants does not affect the uptake of dye significantly. The mass transfer kinetic approach has been applied for the determination of various parameters necessary for the designing of fixed-bed contactors. Chemical regeneration has been achieved with acetone in order to recover the loaded dye and restore the column to its original capacity without dismantling the same.

  4. Photoinduced conformational changes in DNA by poly(vinyl alcohol) carrying a malachite green moiety for protecting DNA against attack by nuclease.

    PubMed

    Uda, Ryoko M; Matsui, Takashi

    2015-11-14

    Light is a highly advantageous means of specific cell targeting. Though targeted gene delivery is an important characteristic of an ideal delivery vehicle, there has been little effort to develop a photoresponsive vector. Among nonviral vectors, cationic substances interact effectively with negatively charged DNA. With this property in mind, we designed copolymers of poly(vinyl alcohol) carrying a malachite green moiety (PVAMG) with different molecular weights. Though PVAMG has no affinity for DNA in the absence of light, it undergoes photoionization in the presence of light to afford cationic DNA binding sites. The DNA-PVAMG complex was investigated with respect to DNA conformational changes and its protective nature, which are important properties for nonviral vectors. PVAMG irradiation promoted DNA conformational transitions from coils to partial globules to compacted globules. The complex had a protective effect against DNase I after PVAMG irradiation, while DNA was degraded under dark conditions. The effect on DNA transition and the protective nature were sensitive to the molecular weight of PVAMG. The data regarding binding constants and binding mode provided insight into the structure of the DNA-PVAMG complex. To withstand DNase I attacks, complexation results in the compaction of DNA, which is further covered with PVAMG.

  5. Optimization of the combined ultrasonic assisted/adsorption method for the removal of malachite green by gold nanoparticles loaded on activated carbon: experimental design.

    PubMed

    Roosta, M; Ghaedi, M; Shokri, N; Daneshfar, A; Sahraei, R; Asghari, A

    2014-01-24

    The present study was aimed to experimental design optimization applied to removal of malachite green (MG) from aqueous solution by ultrasound-assisted removal onto the gold nanoparticles loaded on activated carbon (Au-NP-AC). This nanomaterial was characterized using different techniques such as FESEM, TEM, BET, and UV-vis measurements. The effects of variables such as pH, initial dye concentration, adsorbent dosage (g), temperature and sonication time on MG removal were studied using central composite design (CCD) and the optimum experimental conditions were found with desirability function (DF) combined response surface methodology (RSM). Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo -first order, pseudo-second order, Elovich and intraparticle diffusion models applicability was tested for experimental data and the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed adsorbent (0.015 g) is applicable for successful removal of MG (RE>99%) in short time (4.4 min) with high adsorption capacity (140-172 mg g(-1)).

  6. A label-free near-infrared fluorescent assay for the determination of deoxyribonuclease I activity based on malachite green/G-quadruplexes.

    PubMed

    Sun, Shao-Kai; Wang, Bei-Bei; Yan, Xiu-Ping

    2013-05-07

    Owing to the biological and clinical significance of deoxyribonuclease I (DNase I), it is highly desirable to develop near-infrared (NIR) fluorescent assays for the determination of DNase I activity. Here we report a label-free NIR fluorescent assay for selective determination of DNase I activity based on malachite green (MG)/G-quadruplexes. In the presence of Na(+) or K(+), single stranded DNA (ssDNA) is able to form a G-quadruplex structure, thus to increase the rigidity of MG structure and result in a remarkable NIR fluorescence. As DNase I is capable of cleaving all types of DNA indiscriminately to release nucleotide products, the G-quadruplexes are cleaved into oligonucleotides in the presence of DNase I. As a result, the rigidity of MG structure is reduced, and the NIR fluorescence of the solution decreases with increase of DNase I activity, providing a useful platform for low-cost, label-free and convenient detection of DNase I activity. Under the optimum conditions, the proposed label-free NIR fluorescent assay gave a detection limit of 1 u mL(-1), and a relative standard deviation of 3.2% for eleven replicate detections of 50 u mL(-1) DNase I. The proposed assay was applied to the determination of DNase I activity in spiked human urine samples with recoveries from 99.1 to 109.0%.

  7. Optimization of the combined ultrasonic assisted/adsorption method for the removal of malachite green by gold nanoparticles loaded on activated carbon: Experimental design

    NASA Astrophysics Data System (ADS)

    Roosta, M.; Ghaedi, M.; Shokri, N.; Daneshfar, A.; Sahraei, R.; Asghari, A.

    2014-01-01

    The present study was aimed to experimental design optimization applied to removal of malachite green (MG) from aqueous solution by ultrasound-assisted removal onto the gold nanoparticles loaded on activated carbon (Au-NP-AC). This nanomaterial was characterized using different techniques such as FESEM, TEM, BET, and UV-vis measurements. The effects of variables such as pH, initial dye concentration, adsorbent dosage (g), temperature and sonication time on MG removal were studied using central composite design (CCD) and the optimum experimental conditions were found with desirability function (DF) combined response surface methodology (RSM). Fitting the experimental equilibrium data to various isotherm models such as Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich models show the suitability and applicability of the Langmuir model. Kinetic models such as pseudo -first order, pseudo-second order, Elovich and intraparticle diffusion models applicability was tested for experimental data and the second-order equation and intraparticle diffusion models control the kinetic of the adsorption process. The small amount of proposed adsorbent (0.015 g) is applicable for successful removal of MG (RE > 99%) in short time (4.4 min) with high adsorption capacity (140-172 mg g-1).

  8. Three dimensional design of large-scale TiO(2) nanorods scaffold decorated by silver nanoparticles as SERS sensor for ultrasensitive malachite green detection.

    PubMed

    Tan, En-Zhong; Yin, Peng-Gang; You, Ting-Ting; Wang, Hua; Guo, Lin

    2012-07-25

    We have designed a large-scale three-dimensional (3D) hybrid nanostructure as surface-enhanced Raman scattering (SERS) sensor by decorating silver nanoparticles on TiO2 nanorods scaffold (Ag/TiO2). Taking p-mercaptobenzoic acid (PMBA) as the probe molecule, the SERS signals collected by point-to-point and time mapping modes show that the relative standard deviation (RSD) in the intensity of the main Raman vibration modes (1079, 1586 cm(-1)) is less than 10%, demonstrating good spatial uniformity and time stability. This hybrid substrate also exhibits excellent SERS enhancement effect due to the formation of high-density hot spots among the AgNPs, which was proved by finite-difference time-domain (FDTD) simulations. The application of the new nanostructures as SERS sensors was demonstrated with the detection of malachite green (MG). The quantification of MG can be accomplished with the detection limit of 1 × 10(-12) M based on the Raman intensity. The results show that the Ag/TiO2 nanostructure can be a promising candidate for SERS sensor.

  9. Highly efficient removal of Malachite green from water by a magnetic reduced graphene oxide/zeolitic imidazolate framework self-assembled nanocomposite

    NASA Astrophysics Data System (ADS)

    Lin, Kun-Yi Andrew; Lee, Wei-Der

    2016-01-01

    Compared to the relatively low adsorption capacities of conventional adsorbents for Malachite Green (MG) (i.e., ∼500 mg g-1), zeolitic imidazolate framework (ZIF) appears to be a promising adsorbent considering its significantly high adsorption capacity (i.e., >2000 mg g-1). Nevertheless, using such a nano-scale ZIF material for adsorption may lead to secondary contamination from the release of nanomaterials to the environment. Thus, ZIF has to be recovered conveniently to prevent the secondary contamination and facilitate the separation of adsorbent from water after adsorption. To this end, in this study ZIF nanocrystals were loaded on the sheet-like magnetic reduced graphene oxide (MRGO) to form a self-assembled MRGO/ZIF. The self-assembly of MRGO/ZIF was achieved possibly via the electrostatic attraction and the π-π stacking interaction between MRGO and ZIF. The resultant MRGO/ZIF exhibited an ultra-high adsorption capacity for MG (∼3000 mg g-1). The adsorption kinetics, isotherm, activation and thermodynamics were also determined. Other factors affecting the adsorption were examined including temperature, pH and co-existing ions/compound. To demonstrate that MRGO/ZIF can be recovered and reused, a multiple-cycle of MG adsorption using the regenerated MRGO/ZIF was revealed and the recyclability remained highly efficient and stable. The highly-effective, recoverable and re-usable features enable MRGO/ZIF a promising adsorbent to remove MG from water.

  10. A novel "dual-potential" electrochemiluminescence aptasensor array using CdS quantum dots and luminol-gold nanoparticles as labels for simultaneous detection of malachite green and chloramphenicol.

    PubMed

    Feng, Xiaobin; Gan, Ning; Zhang, Huairong; Yan, Qing; Li, Tianhua; Cao, Yuting; Hu, Futao; Yu, Hongwei; Jiang, Qianli

    2015-12-15

    A novel type of "dual-potential" electrochemiluminescence (ECL) aptasensor array was fabricated on a homemade screen-printed carbon electrode (SPCE) for simultaneous detection of malachite green (MG) and chloramphenicol (CAP) in one single assay. The SPCE substrate consisted of a common Ag/AgCl reference electrode, carbon counter electrode and two carbon working electrodes (WE1 and WE2). In the system, CdS quantum dots (QDs) were modified on WE1 as cathode ECL emitters and luminol-gold nanoparticles (L-Au NPs) were modified on WE2 as anode ECL emitters. Then the MG aptamer complementary strand (MG cDNA) and CAP aptamer complementary strand (CAP cDNA) were attached on CdS QDs and L-Au NPs, respectively. The cDNA would hybridize with corresponding aptamer that was respectively tagged with cyanine dye (Cy5) (as quenchers of CdS QDs) and chlorogenic acid (CA) (as quenchers of l-Au NPs) using poly(ethylenimine) (PEI) as a bridging agent. PEI could lead to a large number of quenchers on the aptamer, which increased the quenching efficiency. Upon MG and CAP adding, the targets could induce strand release due to the highly affinity of analytes toward aptamers. Meanwhile, it could release the Cy5 and CA, which recovered cathode ECL of CdS QDs and anode ECL of L-Au NPs simultaneously. This "dual-potential" ECL strategy could be used to detect MG and CAP with the linear ranges of 0.1-100 nM and 0.2-150 nM, with detection limits of 0.03 nM and 0.07 nM (at 3sB), respectively. More importantly, this designed method was successfully applied to determine MG and CAP in real fish samples and held great potential in the food analysis.

  11. Visual endpoint detection of Escherichia coli O157:H7 using isothermal Genome Exponential Amplification Reaction (GEAR) assay and malachite green.

    PubMed

    Jothikumar, Prithiviraj; Narayanan, Jothikumar; Hill, Vincent R

    2014-03-01

    Rapid and specific detection methods for bacterial agents in drinking water are important for disease prevention and responding to suspected contamination events. In this study, an isothermal Genome Exponential Amplification Reaction (GEAR) assay for Escherichia coli O157:H7 was designed specifically to recognize a 199-bp fragment of the lipopolysaccharide gene (rfbE) for rapid testing of water samples. The GEAR assay was found to be specific for E. coli O157:H7 using 10 isolates of E. coli O157:H7 and a panel of 86 bacterial controls. The GEAR assay was performed at a constant temperature of 65°C using SYTO 9 intercalating dye. Detection limits were determined to be 20 CFU for the GEAR assay. When SYTO 9 fluorescence was measured using a real-time PCR instrument, the assay had the same detection limit as when malachite green was added to the reaction mix and a characteristic blue color was visually observed in positive reactions. The study also found that 50 and 20 CFU of E. coli O157:H7 seeded into 100-liter of tap water could be detected by the GEAR assays after the sample was concentrated by hollow-fiber ultrafiltration (HFUF) and approximately 10% of HFUF concentrate was cultured using trypticase soy broth-novobiocin. When applied to 19 surface water samples collected from Tennessee and Kentucky, the GEAR assay and a published real-time PCR assay both detected E. coli O157:H7 in two of the samples. The results of this study indicate that the GEAR assay can be sensitive for rapid detection of E. coli O157:H7 in water samples using fluorometric instruments and visual endpoint determination.

  12. Photocatalytic discoloration of aqueous malachite green solutions by UV-illuminated TiO2 nanoparticles under air and nitrogen atmospheres: effects of counter-ions and pH.

    PubMed

    Rengifo-Herrera, Julián Andrés; Pizzio, Luis René; Blanco, Mirta Noemí; Roussel, Christophe; Pulgarin, César

    2011-01-01

    Under air atmosphere, the photocatalytic discoloration of malachite green (MG) aqueous solutions (a triphenylmethane dye) in the presence of TiO(2) and UV light followed an oxidative pathway, involving an N-demethylation process evidenced by a blue shifting of the main absorption band with a maximum at 618 nm. This oxidative process was affected by the nature of the dye counter-ion and the pH of the solution. At pH 6.0, the oxidation was found to be faster than at pH 3.0, perhaps due to the poor interactions between MG and the semiconductor surface. Furthermore, with the presence of oxalate as counter-ion, the oxidative photocatalytic discoloration was negatively affected mainly at acidic pH. Under nitrogen atmosphere, some evidence was found about the double behaviour of MG when involved in the photocatalytic discoloration reactions pertaining to TiO(2) under these conditions. MG could be simultaneously oxidized, forming N-demethylated by-products, or reduced, thus leading to leuco-malachite green (LMG) (a colorless and toxic substance) as the main product. The LMG formation is favoured at low pH in the presence of oxalate as counter-ion.

  13. A versatile SERS-based immunoassay for immunoglobulin detection using antigen-coated gold nanoparticles and malachite green-conjugated protein A/G

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A surface enhanced Raman scattering (SERS) immunoassay for antibody detection in serum is described in the present work. The developed assay is conducted in solution and utilizes Au nanoparticles coated with the envelope (E) protein of West Nile Virus (WNV) as the SERS-active substrate and malachite...

  14. Preparation of nanomaterials for the ultrasound-enhanced removal of Pb(2+) ions and malachite green dye: Chemometric optimization and modeling.

    PubMed

    Dil, Ebrahim Alipanahpour; Ghaedi, Mehrorang; Asfaram, Arash; Hajati, Shaaker; Mehrabi, Fatemeh; Goudarzi, Alireza

    2017-01-01

    Copper oxide nanoparticle-loaded activated carbon (CuO-NP-AC) was synthesized and characterized using different techniques such as FE-SEM, XRD and FT-IR. It was successfully applied for the ultrasound-assisted simultaneous removal of Pb(2+) ions and malachite green (MG) dye in binary system from aqueous solution. The effect of important parameters was modeled and optimized by artificial neural network (ANN) and response surface methodology (RSM). Maximum simultaneous removal percentages (>99.0%) were found at 25mgL(-1), 20mgL(-1), 0.02g, 5min and 6.0 corresponding to initial Pb(2+) concentration, initial MG concentration, CuO-NP-AC amount, ultrasonication time and pH, respectively. The precision of the equation obtained by RSM was confirmed by the analysis of variance and calculation of correlation coefficient relating the predicted and the experimental values of ultrasound-assisted simultaneous removal of the analytes. A good agreement between experimental and predicted values was observed. A feed-forward neural network with a topology optimized by response surface methodology was successfully applied for the prediction of ultrasound-assisted simultaneous removal of Pb(2+) ions and MG dye in binary system by CuO-NPs-AC. The number of hidden neurons, MSE, R(2), number of epochs and error histogram were chosen for ANN modeling. Then, Langmuir, Freundlich, Temkin and D-R isothermal models were applied for fitting the experimental data. It was found that the Langmuir model well describes the isotherm data with a maximum adsorption capacity of 98.328 and 87.719mgg(-1) for Pb(2+) and MG, respectively. Kinetic studies at optimum condition showed that maximum Pb(2+) and MG adsorption is achieved within 5min of the start of most experiments. The combination of pseudo-second-order rate equation and intraparticle diffusion model was applicable to explain the experimental data of ultrasound-assisted simultaneous removal of Pb(2+) and MG at optimum condition obtained from RSM.

  15. River and fish pollution in Malaysia: A green ergonomics perspective.

    PubMed

    Poon, Wai Ching; Herath, Gamini; Sarker, Ashutosh; Masuda, Tadayoshi; Kada, Ryohei

    2016-11-01

    Human activities, such as industrial, agricultural, and domestic pursuits, discharge effluents into riverine ecological systems that contains aquatic resources, such as fish, which are also used by humans. We conducted case studies in Malaysia to investigate the impacts of these human activities on water and fish resources, as well as on human well-being from an ergonomics perspective. This research shows that a green ergonomics approach can provide us with useful insights into sustainable relationships between humans and ecology in facilitating human well-being in consideration of the overall performance of the social-ecological system. Heavy metal concentrations contained in the effluents pollute river water and contaminate fish, eventually creating significant health risks and economic costs for residents, including the polluters. The study suggests a number of policy interventions to change human behavior and achieve greater collaboration between various levels of government, academia, civil society, and businesses to help establish sustainable relationships between humans and ecology in Malaysia.

  16. Fish community responses to green tides in shallow estuarine and coastal areas

    NASA Astrophysics Data System (ADS)

    Le Luherne, E.; Réveillac, E.; Ponsero, A.; Sturbois, A.; Ballu, S.; Perdriau, M.; Le Pape, O.

    2016-06-01

    All over the world, numerous bays and estuarine systems that are known to shelter essential fish habitats are experiencing proliferations of green macroalgae known as green tides. Although the processes that enhance green tides in response to nutrient enrichment are well known, their consequences for ecological communities -especially for ichthyofauna- remain poorly studied. To estimate these consequences, this analysis focused on the two types of shallow systems that are experiencing green tides: sandy beaches and estuarine mudflats. In these two systems, macroalgae proliferation and fish community were surveyed along seasonal cycles at control and impacted sites that shared similar physico-chemical parameters and sediment structure. To analyse the consequences of green tides on the fish community, a Before-After Control-Impact approach was used. This approach reveals no difference between fish communities at the control and impacted sites before the macroalgal bloom. Then, it underlines an influence of green tides on the fish community, and this influence varies according to the composition, density and duration of the macroalgal bloom. Indeed, when intertidal systems experienced short proliferation and/or weak density, green tides did not seem to impact the fish community. However, when green macroalgae proliferated in large quantities and/or when the proliferation lasted for long periods, the fish community was significantly affected. These modifications in the fish community led to a significant decrease in fish species diversity and density until fish disappeared from impacted sites at high proliferations. Furthermore, the response of fish species to green tides differed according to their functional guilds. Negative consequences for benthic and marine juvenile fish species were beginning at low proliferations, whereas for pelagic fish species they occurred only at high proliferations. Thus, green tides significantly affect fish habitat suitability because

  17. Simultaneous spectrophotometric determination of crystal violet and malachite green in water samples using partial least squares regression and central composite design after preconcentration by dispersive solid-phase extraction.

    PubMed

    Razi-Asrami, Mahboobeh; Ghasemi, Jahan B; Amiri, Nayereh; Sadeghi, Seyed Jamal

    2017-04-01

    In this paper, a simple, fast, and inexpensive method is introduced for the simultaneous spectrophotometric determination of crystal violet (CV) and malachite green (MG) contents in aquatic samples using partial least squares regression (PLS) as a multivariate calibration technique after preconcentration by graphene oxide (GO). The method was based on the sorption and desorption of analytes onto GO and direct determination by ultraviolet-visible spectrophotometric techniques. GO was synthesized according to Hummers method. To characterize the shape and structure of GO, FT-IR, SEM, and XRD were used. The effective factors on the extraction efficiency such as pH, extraction time, and the amount of adsorbent were optimized using central composite design. The optimum values of these factors were 6, 15 min, and 12 mg, respectively. The maximum capacity of GO for the adsorption of CV and MG was 63.17 and 77.02 mg g(-1), respectively. Preconcentration factors and extraction recoveries were obtained and were 19.6, 98% for CV and 20, 100% for MG, respectively. LOD and linear dynamic ranges for CV and MG were 0.009, 0.03-0.3, 0.015, and 0.05-0.5 (μg mL(-1)), respectively. The intra-day and inter-day relative standard deviations were 1.99 and 0.58 for CV and 1.69 and 3.13 for MG at the concentration level of 50 ng mL(-1), respectively. Finally, the proposed DSPE/PLS method was successfully applied for the simultaneous determination of the trace amount of CV and MG in the real water samples.

  18. No More Green Thumbs!

    ERIC Educational Resources Information Center

    Bland, Judith A.

    1977-01-01

    An alternative method of bacterial spore staining using malachite green is described. This technique is designed to save time and expense by a less messy procedure. Advantages and adaptations of the technique are also given. (MR)

  19. Multiresidue determination of triarylmethane and phenothiazine dyes in fish tissues by LC-MS/MS.

    PubMed

    Tarbin, Jonathan A; Chan, Danny; Stubbings, George; Sharman, Matthew

    2008-09-12

    The occurrence of residues of malachite green and its leuco-metabolite in tissues of farmed fish for human consumption have long been of concern and there is extensive literature on methods of analysis and surveillance for these compounds. Recently, concern has been expressed that the use of other related compounds in place of malachite green may go undetected. This paper describes a new method for extending the range of triarylmethane and related phenothiazine dyes that can be detected in fish. In this procedure 13 parent compounds are monitored, with any potential leuco-forms being oxidized back to the parent prior to determination. The method utilizes a buffer-acetonitrile extraction followed by liquid-liquid extraction. Oxidant is added and the extracts further purified by cation exchange chromatography. Final determination is carried out using LC-MS/MS. The method has been validated to the standards of Commission Decision 2002/657/EC.

  20. Behavioral Response of Reef Fish and Green Sea Turtles to Midfrequency Sonar.

    PubMed

    Watwood, Stephanie L; Iafrate, Joseph D; Reyier, Eric A; Redfoot, William E

    2016-01-01

    There is growing concern over the potential effects of high-intensity sonar on wild fish populations and commercial fisheries. Acoustic telemetry was employed to measure the movements of free-ranging reef fish and sea turtles in Port Canaveral, FL, in response to routine submarine sonar testing. Twenty-five sheepshead (Archosargus probatocephalus), 28 gray snapper (Lutjanus griseus), and 29 green sea turtles (Chelonia mydas) were tagged, with movements monitored for a period of up to 4 months using an array of passive acoustic receivers. Baseline residency was examined for fish and sea turtles before, during, and after the test event. No mortality of tagged fish or sea turtles was evident from the sonar test event. There was a significant increase in the daily residency index for both sheepshead and gray snapper at the testing wharf subsequent to the event. No broad-scale movement from the study site was observed during or immediately after the test.

  1. Probabilistic risk assessment of exposure to leucomalachite green residues from fish products.

    PubMed

    Chu, Yung-Lin; Chimeddulam, Dalaijamts; Sheen, Lee-Yan; Wu, Kuen-Yuh

    2013-12-01

    To assess the potential risk of human exposure to carcinogenic leucomalachite green (LMG) due to fish consumption, the probabilistic risk assessment was conducted for adolescent, adult and senior adult consumers in Taiwan. The residues of LMG with the mean concentration of 13.378±20.56 μg kg(-1) (BFDA, 2009) in fish was converted into dose, considering fish intake reported for three consumer groups by NAHSIT (1993-1996) and body weight of an average individual of the group. The lifetime average and high 95th percentile dietary intakes of LMG from fish consumption for Taiwanese consumers were estimated at up to 0.0135 and 0.0451 μg kg-bw(-1) day(-1), respectively. Human equivalent dose (HED) of 2.875 mg kg-bw(-1) day(-1) obtained from a lower-bound benchmark dose (BMDL10) in mice by interspecies extrapolation was linearly extrapolated to oral cancer slope factor (CSF) of 0.035 (mgkg-bw(-1)day(-1))(-1) for humans. Although, the assumptions and methods are different, the results of lifetime cancer risk varying from 3×10(-7) to 1.6×10(-6) were comparable to those of margin of exposures (MOEs) varying from 410,000 to 4,800,000. In conclusions, Taiwanese fish consumers with the 95th percentile LADD of LMG have greater risk of liver cancer and need to an action of risk management in Taiwan.

  2. Influence of Green Tides in Coastal Nursery Grounds on the Habitat Selection and Individual Performance of Juvenile Fish

    PubMed Central

    Murillo, Laurence; Randon, Marine; Lebot, Clément

    2017-01-01

    Coastal ecosystems, which provide numerous essential ecological functions for fish, are threatened by the proliferation of green macroalgae that significantly modify habitat conditions in intertidal areas. Understanding the influence of green tides on the nursery function of these ecosystems is essential to determine their potential effects on fish recruitment success. In this study, the influence of green tides on juvenile fish was examined in an intertidal sandy beach area, the Bay of Saint-Brieuc (Northwestern France), during two annual cycles of green tides with varying levels of intensity. The responses of three nursery-dependent fish species, the pelagic Sprattus sprattus (L.), the demersal Dicentrarchus labrax (L.) and the benthic Pleuronectes platessa L., were analysed to determine the effects of green tides according to species-specific habitat niche and behaviour. The responses to this perturbation were investigated based on habitat selection and a comparison of individual performance between a control and an impacted site. Several indices on different integrative scales were examined to evaluate these responses (antioxidant defence capacity, muscle total lipid, morphometric condition and growth). Based on these analyses, green tides affect juvenile fish differently according to macroalgal density and species-specific tolerance, which is linked to their capacity to move and to their distribution in the water column. A decreasing gradient of sensitivity was observed from benthic to demersal and pelagic fish species. At low densities of green macroalgae, the three species stayed at the impacted site and the growth of plaice was reduced. At medium macroalgal densities, plaice disappeared from the impacted site and the growth of sea bass and the muscle total lipid content of sprat were reduced. Finally, when high macroalgal densities were reached, none of the studied species were captured at the impacted site. Hence, sites affected by green tides are less

  3. Detection of Cryptosporidium oocysts in green mussels (Perna viridis) from shell-fish markets of Thailand.

    PubMed

    Srisuphanunt, M; Wiwanitkit, Viroj; Saksirisampant, W; Karanis, P

    2009-09-01

    Mussels filter large volumes of water and can concentrate pathogenic organisms, which may act as potential vehicles of transmission to the consumer. A survey study was carried out to investigate the presence of Cryptosporidium protozoan parasites in green mussels (Perna viridis), the smussles pecies most destined for consumption in Thailand. In total, 56 samples were examined from Bangkok (n = 24) and Samut Prakan (n = 32) a wholesale shell-fish markets located at the mouth of the Chao Phraya River. The market for green mussels was closed to the mussel culture placed along the coastal line and this localization may have significant economical impact if the mussels' cultures are found contaminated. Cryptosporidium spp. oocysts were detected by the immunofluorescence antibody method (IFA) in 12.5% of the samples examined. The detection of Cryptosporidium oocysts in green mussels' population of Samut Prakan was higher (15.6%) than in Bangkok market (8.3%). These differences in positive samples from the two locations may be caused by physical, ecological and anthropogenic conditions. This could relay to different contamination levels of marine water by Cryptosporidium oocysts and consequently to contamination of harvested shellfish populations. The results demonstrate that the Cryptosporidium spp. oocysts were found indigenous in mussels from the coastal line of Thailand, indicating that mussels may act as a reservoir of Cryptosporidium foodborne infections for humans.

  4. Synthesis of Copper Pigments, Malachite and Verdigris: Making Tempera Paint

    ERIC Educational Resources Information Center

    Solomon, Sally D.; Rutkowsky, Susan A.; Mahon, Megan L.; Halpern, Erica M.

    2011-01-01

    Malachite and verdigris, two copper-based pigments, are synthesized in this experiment intended for use in a general chemistry laboratory. The preparation of egg tempera paint from malachite is also described. All procedures can be done with a magnetic stir plate, standard glassware present in any first-year laboratory, and household chemicals.…

  5. The potential for human exposure, direct and indirect, to the suspected carcinogenic triphenylmethane dye Brilliant Green from green paper towels.

    PubMed

    Oplatowska, Michalina; Donnelly, Ryan F; Majithiya, Rita J; Glenn Kennedy, D; Elliott, Christopher T

    2011-08-01

    Triphenylmethanes - Malachite Green (MG), Crystal Violet (CV) and Brilliant Green (BG) are dyes with known genotoxic and carcinogenic properties. Apart from being illegally used in aquaculture for treatment of fish diseases they are also applied in industry such as paper production to colour paper towels widely used in hospitals, factories and other locations for hand drying after washing. The present study provides evidence that the triphenylmethane dye (BG) present in green paper towels can migrate through the skin even when the exposure time is short (30-300 s). The transfer of the dye from the towel to food (fish) was also studied and a high amount of colour was found to migrate during overnight exposure. The risk to humans associated with these two dye transfer studies was assessed using a 'margin of exposure approach' on the basis of the toxicological data available for the closely related dye MG and its metabolite Leucomalachite Green. The data indicated that the risk associated with the use of triphenylmethane containing paper towels is of a similar proportion to the risk associated with consumption of fish contaminated with these dyes due to the illegal application in aquaculture.

  6. Gill transcriptome response to changes in environmental calcium in the green spotted puffer fish

    PubMed Central

    2010-01-01

    Background Calcium ion is tightly regulated in body fluids and for euryhaline fish, which are exposed to rapid changes in environmental [Ca2+], homeostasis is especially challenging. The gill is the main organ of active calcium uptake and therefore plays a crucial role in the maintenance of calcium ion homeostasis. To study the molecular basis of the short-term responses to changing calcium availability, the whole gill transcriptome obtained by Super Serial Analysis of Gene Expression (SuperSAGE) of the euryhaline teleost green spotted puffer fish, Tetraodon nigroviridis, exposed to water with altered [Ca2+] was analysed. Results Transfer of T. nigroviridis from 10 ppt water salinity containing 2.9 mM Ca2+ to high (10 mM Ca2+ ) and low (0.01 mM Ca2+) calcium water of similar salinity for 2-12 h resulted in 1,339 differentially expressed SuperSAGE tags (26-bp transcript identifiers) in gills. Of these 869 tags (65%) were mapped to T. nigroviridis cDNAs or genomic DNA and 497 (57%) were assigned to known proteins. Thirteen percent of the genes matched multiple tags indicating alternative RNA transcripts. The main enriched gene ontology groups belong to Ca2+ signaling/homeostasis but also muscle contraction, cytoskeleton, energy production/homeostasis and tissue remodeling. K-means clustering identified co-expressed transcripts with distinct patterns in response to water [Ca2+] and exposure time. Conclusions The generated transcript expression patterns provide a framework of novel water calcium-responsive genes in the gill during the initial response after transfer to different [Ca2+]. This molecular response entails initial perception of alterations, activation of signaling networks and effectors and suggests active remodeling of cytoskeletal proteins during the initial acclimation process. Genes related to energy production and energy homeostasis are also up-regulated, probably reflecting the increased energetic needs of the acclimation response. This study is the

  7. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest). BLACK, GREEN, and RED ABALONES.

    DTIC Science & Technology

    1985-03-01

    F, 7AD-A162 638 SPECIES PROFILES LIFE HISTORIES AND ENVIRONMENTAL 1/ REQUIREMENTS OF COASTAL (U) COOPERATIVE INST FOR MARINE AND ATMOSPHERIC STUDIES...Invertebrates (Pacific Southwest) BLACK, GREEN, AND RED ABALONES by Jerald S. Ault Cooperative Institute for Marine and Atmospheric Studies 4600...Rickenbacker Causeway Miami, FL 33149 Project Manager Larry Shanks Project Officer John Parsons National Coastal Ecosystems TeamV U.S. Fish and Wildlife

  8. The mitochondrial genome of spotted green pufferfish Tetraodon nigroviridis (Teleostei: Tetraodontiformes) and divergence time estimation among model organisms in fishes.

    PubMed

    Yamanoue, Yusuke; Miya, Masaki; Inoue, Jun G; Matsuura, Keiichi; Nishida, Mutsumi

    2006-02-01

    We determined the whole mitochondrial genome sequence for spotted green pufferfish, Tetraodon nigroviridis (Teleostei: Tetraodontiformes). The genome (16,488 bp) contained 37 genes (two ribosomal RNA genes, 22 transfer RNA genes, and 13 protein-coding genes) plus control region as found in other vertebrates, with the gene order identical to that of typical vertebrates. The sequence was used to estimate phylogenetic relationships and divergence times among major lineages of fishes, including representative model organisms in fishes. We employed partitioned Bayesian approaches for these two analyses using two datasets that comprised concatenated amino acid sequences from 12 protein-coding genes (excluding the ND6 gene) and concatenated nucleotide sequences from the 12 protein-coding genes (without 3rd codon positions), 22 transfer RNA genes, and two ribosomal RNA genes. The resultant trees from the two datasets were well resolved and largely congruent with those from previous studies, with spotted green pufferfish being placed in a reasonable phylogenetic position. The approximate divergence times between spotted green pufferfish and model organisms in fishes were 85 million years ago (MYA) vs. torafugu, 183 MYA vs. three-spined stickleback, 191 MYA vs. medaka, and 324 MYA vs. zebrafish, all of which were about twice as old as the divergence times estimated by their earliest occurrences in fossil records.

  9. Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus

    PubMed Central

    Janle, Elsa M.; Freiser, Helene; Manganais, Christopher; Chen, Tzu-Ying; Craig, Bruce A.; Santerre, Charles R.

    2015-01-01

    Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA), a compound used medically to chelate mercury. Rats were given a single oral dose of fish tissue via gavage and one of the treatments. Rats were given access to food for 3 h at 12 h intervals. They were dosed with each of the treatments with each meal. Blood samples were collected for 95 hours. Green tea significantly increased the concentration of total mercury in blood relative to the control, whereas DMSA significantly decreased it. In addition, feeding caused a slight increase in blood mercury for several meals following the initial dose. PMID:26301246

  10. Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus.

    PubMed

    Janle, Elsa M; Freiser, Helene; Manganais, Christopher; Chen, Tzu-Ying; Craig, Bruce A; Santerre, Charles R

    2015-01-01

    Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA), a compound used medically to chelate mercury. Rats were given a single oral dose of fish tissue via gavage and one of the treatments. Rats were given access to food for 3 h at 12 h intervals. They were dosed with each of the treatments with each meal. Blood samples were collected for 95 hours. Green tea significantly increased the concentration of total mercury in blood relative to the control, whereas DMSA significantly decreased it. In addition, feeding caused a slight increase in blood mercury for several meals following the initial dose.

  11. Hydrogen peroxide as a fungicide for fish culture

    USGS Publications Warehouse

    Dawson, V.K.; Rach, J.J.; Schreier, T.M.

    1994-01-01

    Antifungal agents are needed to maintain healthy stocks of fish in the intensive culture systems currently employed in fish hatcheries. Malachite green has been the most widely used antifungal agent; however, its potential for producing teratology in animals and fish precludes further use in fish culture. Preliminary studies at the National Fisheries Research Center, La Crosse, WI, USA (La Crosse Center) indicate that hydrogen peroxide is effective for control of Saprolegnia sp. fungus on incubating eggs of rainbow trout. It is also effective against a wide variety of other organisms such as bacteria, yeasts, viruses, and spores, and has been proposed as a treatment for sea lice on salmon. Hydrogen peroxide and its primary decomposition products, oxygen and water, are not systemic poisons and are considered environmentally compatible. In response to a petition from the La Crosse Center, the U.S. Food and Drug Administration (FDA) recently classified hydrogen peroxide as a 'low regulatory priority' when used for control of fungus on fish and fish eggs. Preliminary tests conducted at the La Crosse Center suggest that prophylactic treatments of 250 to 500 ppm (based on 100% active ingredient) for 15 minutes every other day will inhibit fungal infections on healthy rainbow trout (Oncorhynchus mykiss) eggs. This treatment regime also seems to inhibit fungal development and increase hatching success among infected eggs. Efficacy and safety of hydrogen peroxide as a fungicide for fish are currently being evaluated.

  12. Design and characterization of a direct ELISA for the detection and quantification of leucomalachite green.

    PubMed

    Singh, Gurmit; Koerner, Terence; Gelinas, Jean-Marc; Abbott, Michael; Brady, Beth; Huet, Anne-Catherine; Charlier, Caroline; Delahaut, Philippe; Godefroy, Samuel Benrejeb

    2011-06-01

    Malachite green (MG), a member of the N-methylated triphenylmethane class of dyes, has long been used to control fungal and protozoan infections in fish. MG is easily absorbed by fish during waterborne exposure and is rapidly metabolized into leucomalachite green (LMG), which is known for its long residence time in edible fish tissue. This paper describes the development of an enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of LMG in fish tissue. This development includes a simple and versatile method for the conversion of LMG to monodesmethyl-LMG, which is then conjugated to bovine serum albumin (BSA) to produce an immunogenic material. Rabbit polyclonal antibodies are generated against this immunogen, purified and used to develop a direct competitive enzyme-linked immunosorbent assay (ELISA) for the screening and quantification of LMG in fish tissue. The assay performed well, with a limit of detection (LOD) and limit of quantification (LOQ) of 0.1 and 0.3 ng g(-1) of fish tissue, respectively. The average extraction efficiency from a matrix of tilapia fillets was approximately 73% and the day-to-day reproducibility for these extractions in the assay was between 5 and 10%.

  13. Design and characterization of a direct ELISA for the detection and quantification of leucomalachite green

    PubMed Central

    Singh, Gurmit; Koerner, Terence; Gelinas, Jean-Marc; Abbott, Michael; Brady, Beth; Huet, Anne-Catherine; Charlier, Caroline; Delahaut, Philippe; Godefroy, Samuel Benrejeb

    2011-01-01

    Malachite green (MG), a member of the N-methylated triphenylmethane class of dyes, has long been used to control fungal and protozoan infections in fish. MG is easily absorbed by fish during waterborne exposure and is rapidly metabolized into leucomalachite green (LMG), which is known for its long residence time in edible fish tissue. This paper describes the development of an enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of LMG in fish tissue. This development includes a simple and versatile method for the conversion of LMG to monodesmethyl-LMG, which is then conjugated to bovine serum albumin (BSA) to produce an immunogenic material. Rabbit polyclonal antibodies are generated against this immunogen, purified and used to develop a direct competitive enzyme-linked immunosorbent assay (ELISA) for the screening and quantification of LMG in fish tissue. The assay performed well, with a limit of detection (LOD) and limit of quantification (LOQ) of 0.1 and 0.3 ng g−1 of fish tissue, respectively. The average extraction efficiency from a matrix of tilapia fillets was approximately 73% and the day-to-day reproducibility for these extractions in the assay was between 5 and 10%. PMID:21623496

  14. Visualization of sporopollenin-containing pathogenic green micro-alga Prototheca wickerhamii by fluorescent in situ hybridization (FISH).

    PubMed

    Ueno, Ryohei

    2009-04-01

    Fluorescent in situ hybridization (FISH) using taxon-specific, rRNA-targeted oligonucleotide probes is one of the most powerful tools for the rapid identification of harmful microorganisms. However, eukaryotic algal cells do not always allow FISH probes to permeate over their cell walls. Members of the pathogenic micro-algal genus Prototheca are characterized by their distinctive cell-wall component, sporopollenin, an extremely tough biopolymer that resists acid and alkaline hydrolysis, enzyme attack, and acetolysis. To our knowledge, there has been no report of the successful permeation by the oligonucleotide probes over the cell walls of unicellular green micro-algae, which contain sporopollenin. The DNA probes passed through the cell wall of Prototheca wickerhamii after treating the algal cells with cetyltrimethylammonium bromide (CTAB). Most cells in the middle logarithmic growth phase culture fluoresced when hybridized with the rRNA-targeted universal probe for eukaryotes, though individual cells included in this culture differed in the level of cell-wall vulnerability to attack by the polysaccharide-degrading enzyme, thus reflecting the different stages of the life cycle. This is the first report regarding the visualization of sporopollenin-containing, green micro-algal cells by FISH.

  15. De-eutrophication of effluent wastewater from fish aquaculture by using marine green alga Ulva pertusa

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Wang, Zengfu; Lin, Wei

    2010-03-01

    The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH{4/+}, NO{3/-}, NO{2/-} as well as the total dissolved inorganic nitrogen (DIN). The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 μmol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and could easily lead to phytoplankton blooms in nature if discarded with no treatment. The de-eutrophication abilities of U. pertusa varied greatly and depended mainly on the original eutrophic level the U. pertusa material was derived from. U. pertusa used to living in low DIN conditions had poor DIN removal abilities, while materials cultured in DIN-enriched seawater showed strong de-eutrophication abilities. In other words, the de-eutrophication ability of U. pertusa was evidently induced by high DIN levels. The de-eutrophication capacity of U. pertusa seemed to also be light dependent, because it was weaker in darkness than under illumination. However, no further improvement in the de-eutrophication capacity of U. pertusa was observed once the light intensity exceeded 300 μmol M2 S-1. Results of semi-continuous wastewater replacement experiments showed that U. pertusa permanently absorbed nutrients from eutrophicated wastewater at a mean rate of 299 mg/kg fresh weight per day (126 mg/kg DIN during the night, 173 mg/kg in daytime). Based on the above results, engineered de-eutrophication of wastewater by using a U. pertusa filter system seems feasible. The algal quantity required to purify all the eutrophicated outflow wastewater from the Qingdao Yihai Hatchery Center into oligotrophic level I clean seawater was also estimated using the daily discharged wastewater, the average DIN concentration released and the de-eutrophication capacity of U. pertusa.

  16. Detection of Prohibited Fish Drugs Using Silver Nanowires as Substrate for Surface-Enhanced Raman Scattering

    PubMed Central

    Song, Jia; Huang, Yiqun; Fan, Yuxia; Zhao, Zhihui; Yu, Wansong; Rasco, Barbara A.; Lai, Keqiang

    2016-01-01

    Surface-enhanced Raman scattering or surface-enhanced Raman spectroscopy (SERS) is a promising detection technology, and has captured increasing attention. Silver nanowires were synthesized using a rapid polyol method and optimized through adjustment of the molar ratio of poly(vinyl pyrrolidone) and silver nitrate in a glycerol system. Ultraviolet-visible spectrometry, X-ray diffraction, and transmission electron microscopy were used to characterize the silver nanowires. The optimal silver nanowires were used as a SERS substrate to detect prohibited fish drugs, including malachite green, crystal violet, furazolidone, and chloramphenicol. The SERS spectra of crystal violet could be clearly identified at concentrations as low as 0.01 ng/mL. The minimum detectable concentration for malachite green was 0.05 ng/mL, and for both furazolidone and chloramphenicol were 0.1 μg/mL. The results showed that the as-prepared Ag nanowires SERS substrate exhibits high sensitivity and activity. PMID:28335303

  17. Copper Metal from Malachite Circa 4000 B.C.E.

    ERIC Educational Resources Information Center

    Yee, Gordon T.; Eddleton, Jeannine E.; Johnson, Cris E.

    2004-01-01

    The feasibility of the laboratory production of copper metal from a readily available, naturally occurring mineral malachite utilizing techniques that are consistent with the time period of around 4000 B.C.E. is presented. The starting materials are inexpensive and convenient and the procedure involves no hazardous reagents and produces no…

  18. Initial studies on sperm cryopreservation of a live-bearing fish, the green swordtail Xiphophorus helleri.

    PubMed

    Huang, Changjiang; Dong, Qiaoxiang; Walter, Ronald B; Tiersch, Terrence R

    2004-07-01

    Swordtails and platyfish of the genus Xiphophorus are valuable models for biomedical research and are also commercially raised as ornamental fish valued by aquarists. While research use and commercial interest increases yearly in these fish, cryopreservation of sperm is unexplored in this genus. Xiphophorus are live-bearing fishes characterized by small body sizes, limited sperm volumes, and internal fertilization, an atypical reproductive mode for fish. These attributes make research involving cryopreservation of Xiphophorus germplasm challenging. To explore methods for sperm cryopreservation, this study evaluated the effect of different loading volumes of sperm suspension in 0.25-ml French straws, different dilution ratios of sperm to extender, an osmolality range of extender without cryoprotectant and with dimethyl sulfoxide (DMSO) as cryoprotectant, and short-term storage at room temperature and 4 degrees C after thawing. No significant difference in sperm motility due to straw loading volume was observed after thawing. Sperm motility was observed to decrease with increasing dilution. The osmolality of Hanks' balanced salt solution (HBSS) without cryoprotectant in which the highest sperm motility (67%) was observed was 320 +/- 3 mOsm/kg, which was also the osmolality of X. helleri blood plasma. When cryopreserved with 10% DMSO, however, the highest motilities within 10 min after thawing were observed with HBSS in the range of 240-300 mOsm/kg. Sperm suspended in HBSS at 320 mOsm/kg with a dilution factor of 100 maintained motility for 24h at room temperature, but persisted for 10 days when stored at 4 degrees C. These results provided the first evidence that cryopreservation may be applied to conservation of genetic resources in live-bearing fishes.

  19. Green pigments of the Pompeian artists' palette

    NASA Astrophysics Data System (ADS)

    Aliatis, Irene; Bersani, Danilo; Campani, Elisa; Casoli, Antonella; Lottici, Pier Paolo; Mantovan, Silvia; Marino, Iari-Gabriel; Ospitali, Francesca

    2009-08-01

    Green colored samples on wall paintings and green powder from a pigment pot found in Pompeii area are investigated by micro-Raman, FT-IR and, for one sample, SEM-EDX. To obtain the green color, green earths and malachite were used, together with mixture of Egyptian blue and yellow ochre. The mineralogical identification of the green earths has been attempted through the comparison of the vibrational features, discriminating between celadonite and glauconite spectra. Traces of a modern synthetic pigment containing copper phthalocyanine were found in a fresco fragment.

  20. Potential effects of four Flaming Gorge Dam hydropower operational scenarios on the fishes of the Green River, Utah and Colorado

    SciTech Connect

    Hlohowskyj, I.; Hayse, J.W.

    1995-09-01

    Aerial videography and modeling were used to evaluate the impacts of four hydropower operational scenarios at Flaming Gorge Dam, Utah, on trout and native fishes in the Green River, Utah and Colorado. The four operational scenarios studied were year-round high fluctuations, seasonally adjusted high fluctuations, seasonally adjusted moderate fluctuations, and seasonally adjusted steady flows. Impacts on trout were evaluated by examining differences among scenarios in the areas of inundated substrates that serve as spawning and feeding habitat. All scenarios would provide at least 23 acres per mile of habitat for spawning and food production; seasonally adjusted operations would provide additional areas during periods of sustained high release. Seasonally adjusted high fluctuations would increase inundated areas by 12 to 26% for a short period in winter and spring, but food production and reproduction would not be expected to increase. Seasonally adjusted moderate fluctuations and steady flows would produce similar increases in area, but the longer period of inundation could also result in increased food production and provide additional spawning sites for trout. Impacts on native fishes were assessed by examining daily changes in backwater nursery areas. Compared with year-round high fluctuations, the daily changes in backwater area would decrease by about 47, 89, and 100% under the seasonally adjusted high fluctuation, moderate fluctuation, and steady flow scenarios, respectively. Similarly, daily stage fluctuations during the nursery period would decrease by 72, 89, and 100% under the seasonally adjusted high fluctuation, moderate fluctuation, and steady flow scenarios, respectively. These reductions in daily fluctuations in backwater area and stage would improve conditions in nursery habitats and could in turn improve recruitment and overwinter survival. Introduced fish species could also benefit from the seasonally adjusted operational scenarios.

  1. Effects of twenty-five compounds on four species of aquatic fungi (Saprolegniales) pathogenic to fish

    USGS Publications Warehouse

    Bailey, T.A.

    1984-01-01

    Four species of aquatic fungi (Achlya flagellata, A. racemosa, Saprolegnia hypogyna, and S. megasperma) were exposed to 25 chemicals representing seven classes of compounds for 15 and 60 min, in an effort to identify potential fungicidal agents for use in fish culture. The antifungal activity of each chemical was compared with that of malachite green, a reference compound with known fungicidal properties but not registered for fishery use. Six compounds which inhibited fungal growth on artificial media at concentrations of < 100 mg/l (listed in order of decreasing antifungal activity) were the cationics Du-terA? and copper oxychloride sulfate, the amine LesanA?, the amide BAS-389-O1F and the cationics CuprimyxinA? and RoccalA? II. Certain chemicals from these classes of compounds may have promise as aquatic fungicides.

  2. Microgeographic population structure of green swordail fish: genetic differentiation despite abundant migration.

    PubMed

    Tatarenkov, A; Healey, C I M; Avise, J C

    2010-01-01

    Swordtails (Xiphophorus; Poeciliidae) have figured prominently in research on fish mating behaviours, sexual selection, and carcinogenesis, but their population structures and dispersal patterns have been relatively neglected. Using nine microsatellite loci, we estimated genetic differentiation in Xiphophorus helleri within and between adjacent streams in Belize. The genetic data were complemented by a tagging study of movement within one stream. In the absence of physical dispersal barriers (waterfalls), population structure followed an isolation by distance (IBD) pattern. Genetic differentiation (F(ST) up to 0.07) was significant between and within creeks, despite high dispersal in the latter as judged by the tagging data. Such heterogeneity apparently was a result of genetic drift in local demes, due to small population sizes and highly skewed paternity. The IBD pattern was interrupted by waterfalls, boosting F(ST) above 0.30 between adjacent samples across these barriers. Overall, our results are helpful in understanding the interplay of evolutionary forces and population dynamics in a small fish living in a changeable habitat.

  3. Maximum sustainable speed, energetics and swimming kinematics of a tropical carangid fish, the green jack Caranx caballus.

    PubMed

    Dickson, K A; Donley, J M; Hansen, M W; Peters, J A

    2012-06-01

    Maximum sustained swimming speeds, swimming energetics and swimming kinematics were measured in the green jack Caranx caballus (Teleostei: Carangidae) using a 41 l temperature-controlled, Brett-type swimming-tunnel respirometer. In individual C. caballus [mean ±s.d. of 22·1 ± 2·2 cm fork length (L(F) ), 190 ± 61 g, n = 11] at 27·2 ± 0·7° C, mean critical speed (U(crit)) was 102·5 ± 13·7 cm s⁻¹ or 4·6 ± 0·9 L(F) s⁻¹. The maximum speed that was maintained for a 30 min period while swimming steadily using the slow, oxidative locomotor muscle (U(max,c)) was 99·4 ± 14·4 cm s⁻¹ or 4·5 ± 0·9 L(F) s⁻¹. Oxygen consumption rate (M in mg O₂ min⁻¹) increased with swimming speed and with fish mass, but mass-specific M (mg O₂ kg⁻¹ h⁻¹) as a function of relative speed (L(F) s⁻¹) did not vary significantly with fish size. Mean standard metabolic rate (R(S) ) was 170 ± 38 mg O₂ kg⁻¹ h⁻¹, and the mean ratio of M at U(max,c) to R(S) , an estimate of factorial aerobic scope, was 3·6 ± 1·0. The optimal speed (U(opt) ), at which the gross cost of transport was a minimum of 2·14 J kg⁻¹ m⁻¹, was 3·8 L(F) s⁻¹. In a subset of the fish studied (19·7-22·7 cm L(F) , 106-164 g, n = 5), the swimming kinematic variables of tailbeat frequency, yaw and stride length all increased significantly with swimming speed but not fish size, whereas tailbeat amplitude varied significantly with speed, fish mass and L(F) . The mean propulsive wavelength was 86·7 ± 5·6 %L(F) or 73·7 ± 5·2 %L(T) . Mean ±s.d. yaw and tailbeat amplitude values, calculated from lateral displacement of each intervertebral joint during a complete tailbeat cycle in three C. caballus (19·7, 21·6 and 22·7 cm L(F) ; 23·4, 25·3 and 26·4 cm L(T) ), were 4·6 ± 0·1 and 17·1 ± 2·2 %L(T) , respectively. Overall, the sustained swimming performance, energetics, kinematics, lateral displacement and intervertebral bending angles measured in C. caballus

  4. Sperm cryopreservation of green swordtail Xiphophorus helleri, a fish with internal fertilization.

    PubMed

    Huang, Changjiang; Dong, Qiaoxiang; Walter, Ronald B; Tiersch, Terrence R

    2004-06-01

    Sperm cryopreservation for fishes with internal fertilization is essentially unexplored although many species of these fishes are valuable biomedical research models. To explore methods for sperm cryopreservation within the live-bearing genus Xiphophorus, this study used X. helleri to evaluate the effects of cryoprotectant, osmotic pressure, cooling rate, equilibration time, and sperm-to-extender ratio. Sperm motility and survival duration after thawing showed significant differences among different cryoprotectants with the highest motility at 10 min after thawing obtained with 14% glycerol. With subsequent use of 14% glycerol as the cryoprotectant, the highest motility after thawing was observed with Hanks' balanced salt solution (HBSS) at 300 mOsmol/kg. Samples cooled from 5 to -80 degrees C at 20 degrees C/min yielded the highest post-thaw motility although no significant difference was found in the first 4h after thawing for cooling rates across the range of 20-35 degrees C/min. Evaluation of equilibration time revealed no significant difference between 20 min and 2h, but the highest motility at 10 min after thawing was found with a 20-min equilibration. Dilution ratios of sperm-to-extender at 1:20, 1:60, and 1:120 showed no significant differences in motility and survival duration after thawing, but the dilution of sperm solutions with HBSS (320 mOsmol/kg) immediately after thawing reduced the decline of sperm motility, and significantly prolonged the survival duration. Based on these findings, the highest average sperm motility (77%) at 10 min after thawing was obtained when sperm were suspended in HBSS at 300 mOsmol/kg with 14% glycerol as cryoprotectant, diluted at a ratio of sperm to HBSS-glycerol of 1:20, equilibrated for 10 min, cooled at 20 degrees C/min from 5 to -80 degrees C before being plunged in liquid nitrogen, and thawed in a 40 degrees C water bath for 7s. If diluted immediately after thawing, sperm frozen by the protocol above retained

  5. The rate of predation by fishes on hatchlings of the green turtle ( Chelonia mydas)

    NASA Astrophysics Data System (ADS)

    Gyuris, E.

    1994-07-01

    This study addresses the need for empirical data on the survival of sea turtle hatchlings after entry into the sea by (1) developing a method for measuring marine predation; (2) estimating predation rates while crossing the reef; and (3) investigating the effect of environmental variables on predation rates. Predation rates were quantified by following individual hatchlings, tethered by a 10m monofilament nylon line, as they swam from the water's edge towards the reef crest. Predation rates under particular combinations of environmental variables (tide, time of day, and moon phase) were measured in separate trials. Predation rates varied among trials from 0 to 85% with a mean of 31% (SE=2.5%). The simplest logistic regression model that explained variation in predation contained tide and moon phase as predictor variables. The results suggest that noctural emergence from the nest is a behavioral adaptation to minimize exposure to the heat of the day rather than a predator-escape mechanism. For the green turtle populations breeding in eastern Australia, most first year mortality is caused by predation while crossing the reef within the first hour of entering the sea.

  6. Development of a SYBR green I real-time PCR assay for specific identification of the fish pathogen Aeromonas salmonicida subspecies salmonicida.

    PubMed

    Fernández-Álvarez, Clara; González, Santiago F; Santos, Ysabel

    2016-12-01

    A SYBR Green I real-time polymerase chain reaction protocol for specific detection of the fish pathogen Aeromonas salmonicida subsp. salmonicida was developed and validated for rapid diagnosis of typical furunculosis. The sequence of the aopO gene of A. salmonicida subsp. salmonicida, which encodes for a serine/threonine protein kinase linked to virulence, was chosen for primer design. The selected primers amplified a 119-bp internal fragment of the aopO gene. The specificity test proved that 100 % (40/40) of the A. salmonicida subsp. salmonicida strains tested showed a positive amplification with subspecies-specific melting temperatures (Tm) of 80.75 ± 0.35 °C. Atypical A. salmonicida subspecies and other non-related bacterial fish pathogens did not amplify or showed unspecific melting profiles, except for one strain of A. salmonicida subsp. achromogenes and one strain of A. salmonicida subsp. smithia. The detection sensitivity was 21 fg of purified bacterial DNA per reaction, corresponding to 1-2 bacterial cells and 6-60 bacteria per reaction for seeded kidney and blood. The assay was highly reproducible with low variation coefficient values for intra-run and inter-run assays. The assay also allowed the specific detection of A. salmonicida subsp. salmonicida in tissues of fish naturally and experimentally infected. No amplification was detected when tissues from healthy fish or fish affected by other diseases were tested. The SYBR Green real-time PCR and melt curve analysis developed in this study is a rapid and accurate method for the specific identification of A. salmonicida subsp. salmonicida isolates and its detection on tissues of fish affected by furunculosis.

  7. Screening fungicides for use in fish culture: Evaluation of the agar plug transfer, cellophane transfer, and agar dilution methods

    USGS Publications Warehouse

    Bailey, Tom A.

    1983-01-01

    The reliability, reproducibility, and usefulness of three screening methods -- the cellophane transfer, the agar plug transfer, and the agar dilution -- to screen aquatic fungicides were evaluated. Achlya flagellata and Saprolegnia hypogyna were exposed to 1, 10, and 100 mg/L of malachite green to test each method. The cellophane transfer and agar plug transfer techniques had similar reliability and reproducibility in rating fungicidal activity, and were both superior to the agar dilution technique. The agar plug transfer and agar dilution techniques adequately projected in vivo activity of malachite green, but the cellophane transfer technique overestimated its activity. Overall, the agar plug transfer technique most accurately rated the activity of malachite green and was the easiest test to perform. It therefore appears to be the method of choice for testing aquatic fungicides.

  8. Fluorescence screening of leucomalachite green and leucogentian violet residues in catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tripheylmethane dyes malachite green (MG) and gentian violet (GV) are effective fungicides, ectoparasiticides and disinfectants in aquaculture. This practice may leave toxic residues in seafood which is not allowed by FDA and many regulatory agencies worldwide. In this work, residues of their me...

  9. Efficient removal of chromate and arsenate from individual and mixed system by malachite nanoparticles.

    PubMed

    Saikia, Jiban; Saha, Bedabrata; Das, Gopal

    2011-02-15

    Malachite nanoparticles of 100-150 nm have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate. We report a high adsorption capacity for chromate and arsenate on malachite nanoparticle from both individual and mixed solution in pH ∼4-5. However, the adsorption efficiency decreases with the increase of solution pH. Batch studies revealed that initial pH, temperature, malachite nanoparticles dose and initial concentration of chromate and arsenate were important parameters for the adsorption process. Thermodynamic analysis showed that adsorption of chromate and arsenate on malachite nanoparticles is endothermic and spontaneous. The adsorption of these anions has also been investigated quantitatively with the help of adsorption kinetics, isotherm, and selectivity coefficient (K) analysis. The adsorption data for both chromate and arsenate were fitted well in Langmuir isotherm and preferentially followed the second order kinetics. The binding affinity of chromate is found to be slightly higher than arsenate in a competitive adsorption process which leads to the comparatively higher adsorption of chromate on malachite nanoparticles surface.

  10. Structural characterization of malachite-like coprecipitated precursors of binary CuO-ZnO catalysts

    SciTech Connect

    Porta, P.; De Rossi, S.; Ferraris, G.; Lo Jacono, M.; Minelli, G.; Moretti, G.

    1988-02-01

    Copper and zinc hydroxycarbonates with Cu/Zn atomic ratios of 100/0, 92/8, 85/15, 77/23, 67/33, and 50/50 were prepared by the coprecipitation method. The samples with the ratios 100/0, 92/8 and 85/15 were monophasic with the monoclinic P2/sub 1//a malachite structure, whereas the richer zinc samples contained in addition to the malachite phase the orthorhombic B22/sub 1/2 aurichalcite, whose concentration was very low in the 77/23 specimen but increased continuously with zinc content. The amount of aurichalcite in the biphasic powders has been estimated by means of quantitative X-ray diffraction and differential thermal analysis. With only those X-ray reflections belonging to the malachite structure taken into account, the unit cell constants for all the solid solution hydroxycarbonates have been determined, showing that as a whole the cell volume of malachite decreases continuously with increasing zinc content. This result is related, as shown also by DTA measurements and thermochemical literature data, to an increasing stability of compounds richer in zinc, to increasing covalent effects, and/or to less octahedral site distortion around the metal atoms when zinc substitutes for Cu/sup 2 +/ ions in the malachite lattice. Magnetic susceptibility and thermogravimetric measurements together with diffuse reflectance spectra are also presented and discussed.

  11. On the structural relations of malachite. I. The rosasite and ludwigite structure families.

    PubMed

    Girgsdies, Frank; Behrens, Malte

    2012-04-01

    The crystal structures of malachite Cu(2)(OH)(2)CO(3) and rosasite (Cu,Zn)(2)(OH)(2)CO(3), though not isotypic, are closely related. A previously proposed approach explaining this relation via a common hypothetical parent structure is elaborated upon on the basis of group-subgroup considerations, leading to the conclusion that the aristotype of malachite and rosasite should crystallize in the space group Pbam (No. 55). An ICSD database search for actual representatives of this aristotype leads to the interesting observation that the structure type of ludwigite (Mg,Fe)(2)FeO(2)BO(3), which is adopted by several natural and synthetic oxide orthoborates M(3)O(2)BO(3), is closely related to the proposed malachite-rosasite aristotype and thus to the malachite-rosasite family of hydroxide carbonates M(2)(OH)(2)CO(3) in general. Relations within both structure families and their analogies are summarized in a joint simplified Bärnighausen tree.

  12. Maintaining population persistence in the face of an extremely altered hydrograph: implications for three sensitive fishes in a tributary of the Green River, Utah

    USGS Publications Warehouse

    Bottcher, Jared L.

    2009-01-01

    The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy only 50% of their historic range. Despite these distributional declines, populations of all three species are present in the San Rafael River, a highly regulated tributary of the Green River, Utah, providing an opportunity for research. Our goal was to determine the timing and extent of movement, habitat preferences, and limiting factors, ultimately to guide effective management and recovery of these three species. In 2007-2008, we sampled fish from 25 systematically selected, 300-m reaches in the lower 64 km of the San Rafael River, spaced to capture the range of species, life-stages, and habitat conditions present. We implanted all target species with a passive integrated transponder (PIT) tag, installed a passive PIT tag antennae, and measured key habitat parameters throughout each reach and at the site of native fish capture. We used random forest modeling to identify and rank the most important abiotic and biotic predictor variables, and reveal potential limiting factors in the San Rafael River. While flannelmouth sucker were relatively evenly distributed within our study area, highest densities of roundtail chub and bluehead sucker occurred in isolated, upstream reaches characterized by complex habitat. In addition, our movement and length-frequency data indicate downstream drift of age-0 roundtail chub, and active upstream movement of adult flannelmouth sucker, both from source populations, providing the lower San Rafael River with colonists. Our random forest analysis highlights the importance of pools, riffles, and distance-to-source populations, suggesting that bluehead sucker and roundtail

  13. In vitro and in vivo assessment of the effect of antiprotozoal compounds isolated from Psoralea corylifolia against Ichthyophthirius multifiliis in fish

    PubMed Central

    Song, Kaige; Ling, Fei; Huang, Aiguo; Dong, Wenjing; Liu, Guanglu; Jiang, Chao; Zhang, Qizhong; Wang, Gaoxue

    2015-01-01

    Ichthyophthirius multifiliis, an external fish parasite, often causes significant economic damage to the aquaculture industry. Since the use of malachite green was banned, the search of alternative substance to control I. multifiliis infections becomes stringent. In present study, in vitro and in vivo anti-ich efficacies of isopsoralen and psoralidin, two active compounds isolated from methanol extract of Psoralea corylifolia by bioassay-guided fractionation based on the efficacy of anti-ich encysted tomonts, were evaluated. In vitro antiprotozoal efficacy of psoralidin is much better than that of isopsoralen. Psoralidin can kill all theronts at concentrations of 0.8 mg/L or more during 4 h exposure; and terminate reproduction of I. multifiliis post 6 h exposure of protomonts to 0.9 mg/L and encysted tomonts to 1.2 mg/L. In vivo trials showed that 5 h exposure of infected fish to 2.5 mg/L of psoralidin significantly reduced the number of theronts released from tomonts. Furthermore, we observed that a part of protomonts, collected from infected fish post treatment, presented characteristic morphological changes of apoptosis after staining with Annexin V-EGFP/propidium iodide, indicating the possible mechanism of psoralidin against I. multifiliis trophont in situ. On the basis of these results, psoralidin can be used as a potential lead compound for the development of commercial drug against I. multifiliis. PMID:26042195

  14. Black, green, and red abalones. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest. )

    SciTech Connect

    Ault, J.S.

    1985-03-01

    Black, green, and red abalones (Haliotis cracherodii, H. fulgens, and H. rufescens, respectivley) are of commercial and ecological importance and are distributed widely along the California coast. The abalones are morphologically similar; species are distinguished by particular shell sculpture, color, and body characteristics. Their latitudinal and bathymetric distribution is stratified and most closely related to temperature. Small juveniles eat mainly microflora; adults eat primarily drift macro-algae, preferring specific brown or red algae, when available. Spawning occurs during summer; gonad ripening depends on food quality and quantity and water temperature. Larvae are lecithotrophic and remain planktonic for periods of 5 to 14 days after hatching; settling is substrate specific. Postlarvae and adults require hard substrate for attachment. Juveniles are cryptic, adults usually more exposed. Growth rates are similar, although maximum size varies with species. Increases in shell length and body weight correlate positively with food abundance and temperature. Below depths of 6 m, sea urchins are major competitors for food and space. Predation by invertebrates is low. Decreased abalone production from central California is associated with range expansion and increased predation by sea otters, the major source of abalone mortality. General declines in California landings are due to mortality from improper picking and replacement, habitat degradation, and perhaps overfishing. Commercial and sport diving efforts have increased sharply, whereas annual landings of abalones declined from 1965 to 1982.

  15. ATPase activity measurement of DNA replicative helicase from Bacillus stearothermophilus by malachite green method.

    PubMed

    Yang, Mu; Wang, Ganggang

    2016-09-15

    The DnaB helicase from Bacillus stearothermophilus (DnaBBst) was a model protein for studying the bacterial DNA replication. In this work, a non-radioactive method for measuring ATPase activity of DnaBBst helicase was described. The working parameters and conditions were optimized. Furthermore, this method was applied to investigate effects of DnaG primase, ssDNA and helicase loader protein (DnaI) on ATPase activity of DnaBBst. Our results showed this method was sensitive and efficient. Moreover, it is suitable for the investigation of functional interaction between DnaB and related factors.

  16. A Malachite Green-Based Assay to Assess Glucan Phosphatase Activity

    PubMed Central

    Sherwood, Amanda R.; Paasch, Bradley C.; Worby, Carolyn A.; Gentry, Matthew S.

    2012-01-01

    With the recent discovery of a unique class of dual-specificity phosphatases that dephosphorylate glucans, we report an in vitro assay tailored for the detection of phosphatase activity against phosphorylated glucans. We demonstrate that in contrast to a general phosphatase assay utilizing a synthetic substrate, only phosphatases that possess glucan phosphatase activity liberate phosphate from the phosphorylated glucan amylopectin using the described assay. This assay is simple and cost-effective, providing reproducible results that clearly establish the presence or absence of glucan phosphatase activity. The assay described will be a useful tool in characterizing emerging members of the glucan phosphatase family. PMID:23201267

  17. Snail shell as coagulant aid in the alum precipitation of malachite green from aqua system.

    PubMed

    Oladoja, Nurudeen A; Aliu, Yekini D

    2009-05-30

    The ability of snail shell (SS) to act as coagulant aid in the alum precipitation of a basic dye (MG) was investigated. The proximate physicochemical characterization of the SS showed the pH(solution) to be 8.01, high fraction of the inorganic constituents (ash content=93.76%), the presence of Ca(2+) (99.74%) as the major metal ion present and the point zero charge (PZC) found at pH 7.9. The X-ray diffractometric analysis revealed the presence of aragonite. The stability and leaching of the SS, tested in different aqua medium (acidic, basic and neutral solutions) showed that the SS was less stable in the acidic medium. Both the alum and the SS were used, differently, for the dye precipitation. The alum alone had no precipitating effect on the MG dye molecules while SS alone was able to reduce the intensity of the dye. When the SS was used as coagulant aid in alum precipitation, the percentage of the MG molecule removed was enhanced. The effects of some process variables (coagulant/coagulant aid dosage, pH and flocculation time) were optimized by method of continuous variation. The optimum pH for the MG removal was found to range between 4 and 5 but the amount of MG removed was appreciable at all the pH studied. Studies on the effect of time on the flocculation of the precipitated MG molecule showed that the problem of redispersion and restabilisation encountered in alum precipitation could be overcome using alum-SS combination. The settling characteristics of the sludge obtained from the use of SS alone and alum-SS combination was studied by measuring the sludge volume index (SVI, mg/g) over time. The value of the SVI (mg/g) showed that the sludge produced from the alum-SS combination had better settling characteristics than the sludge got from the use of SS alone.

  18. Production of F1 Offspring with Vitrified Sperm from a Live-Bearing Fish, the Green Swordtail Xiphophorus hellerii

    PubMed Central

    Cuevas-Uribe, Rafael; Yang, Huiping; Daly, Jonathan; Savage, Markita G.; Walter, Ronald B.

    2011-01-01

    Abstract This study reports the first production of offspring with vitrified sperm from a live-bearing fish Xiphophorus hellerii. The overall goal of this study was to develop streamlined protocols for integration into a standardized approach for vitrification of aquatic species germplasm. The objectives were to (1) estimate acute toxicity of cryoprotectants, (2) evaluate vitrification solutions, (3) compare different thawing methods, (4) evaluate membrane integrity of post-thaw sperm vitrified in different cryoprotectants, and (5) evaluate the fertility of vitrified sperm. Nine cryoprotectants and two commercial vitrification additives were tested for acute toxicity and glass forming ability, alone and in combination. Two vitrification solutions, 40% glycerol (Gly) and 20% Gly+20% ethylene glycol (EG) in 500 mOsmol/kg Hanks' balanced salt solution (HBSS), were selected for vitrification of 10 μL sperm samples using inoculating loops plunged into liquid nitrogen. Samples were thawed at 24°C (one loop in 5 μL of HBSS or three loops in 500 μL of HBSS). Samples thawed in 500 μL were concentrated by centrifugation (1000 g for 5 min at 4°C) into 5 μL for artificial insemination. Offspring were produced from virgin females inseminated with sperm vitrified with 20% Gly+20% EG and concentrated by centrifugation. PMID:21883000

  19. Effects of different omega-3 sources, fish oil, krill oil, and green-lipped mussel against cytokine-mediated canine cartilage degradation.

    PubMed

    Buddhachat, Kittisak; Siengdee, Puntita; Chomdej, Siriwadee; Soontornvipart, Kumpanart; Nganvongpanit, Korakot

    2017-01-11

    Our purpose was to evaluate the protective effect of three marine omega-3 sources, fish oil (FO), krill oil (KO), and green-lipped mussel (GLM) against cartilage degradation. Canine cartilage explants were stimulated with either 10 ng/mL interleukin-1β (IL-1β) or IL-1β/oncostatin M (10 ng/mL each) and then treated with various concentrations of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA; 3 and 30 μg/mL), FO, KO, or GLM (250, 500, and 1000 μg/mL) for 28 days. Gene expression was then investigated in primary canine chondrocytes. Our results showed that DHA and EPA as well as omega-3 sources could suppress matrix degradation in cytokine-induced cartilage explants by significantly reducing the increase of sulfated glycosaminoglycans (s-GAGs) and preserving uronic acid and hydroxyproline content (except GLM). These agents were not able to reduce IL-1β-induced IL1B and TNFA expression but were able to down-regulate the expression of the catabolic genes MMP1, MMP3, and MMP13 and up-regulate the anabolic genes AGG and COL2A1; FO and KO were especially effective. Our findings indicated that FO and KO were superior to GLM for their protective effect against proteoglycan and collagen degradation. Hence, FO and KO could serve as promising sources of chondroprotective agents.

  20. Spin excitations in the two-dimensional strongly coupled dimer system malachite

    NASA Astrophysics Data System (ADS)

    Canévet, E.; Fâk, B.; Kremer, R. K.; Chun, J. H.; Enderle, M.; Gordon, E. E.; Bettis, J. L.; Whangbo, M.-H.; Taylor, J. W.; Adroja, D. T.

    2015-02-01

    The mineral malachite, Cu 2(OD )2CO 3, has a quantum spin-liquid ground state and no long-range magnetic order down to at least T =0.4 K. Inelastic neutron scattering measurements show that the excitation spectrum consists of dispersive gapped singlet-triplet excitations, characteristic of spin-1/2 dimer-forming Heisenberg antiferromagnets. We identify a distinct two-dimensional dimerized coupling scheme with strong interdimer coupling J'/J1≈0.3 that places malachite between strongly coupled alternating chains, square lattice antiferromagnets, and infinite-legged ladders. The geometry of the interaction scheme resembles the staggered dimer lattice, which may allow unconventional quantum criticality.

  1. Proteomic analysis of blood cells in fish exposed to chemotherapeutics: evidence for long term effects.

    PubMed

    Pierrard, Marie-Aline; Kestemont, Patrick; Phuong, Nguyen Thanh; Tran, Minh Phu; Delaive, Edouard; Thezenas, Marie-Laëtitia; Dieu, Marc; Raes, Martine; Silvestre, Frédéric

    2012-04-18

    Proteomics technology are increasingly used in ecotoxicological studies to characterize and monitor biomarkers of exposure. The present study aims at identifying long term effects of malachite green (MG) exposure on the proteome of peripheral blood mononuclear cells (PBMC) from the Asian catfish, Pangasianodon hypophthalmus. A common (0.1 ppm) concentration for therapeutic treatment was applied twice with a 72 h interval. PBMC were collected directly at the end of the second bath of MG (T1) and after 1 month of decontamination (T2). Analytical 2D-DIGE gels were run and a total of 2551±364 spots were matched. Among them, MG induced significant changes in abundance of 116 spots with no recovery after one month of decontamination. Using LC-MS/MS and considering single identification per spot, we could identify 25 different proteins. Additionally, MG residues were measured in muscle and in blood indicating that leuco-MG has almost totally disappeared after one month of decontamination. This work highlights long term effects of MG treatment on the PBMC proteome from fish intended for human consumption.

  2. On-line Raman spectroscopy of calcite and malachite during irradiation with swift heavy ions

    NASA Astrophysics Data System (ADS)

    Dedera, Sebastian; Burchard, Michael; Glasmacher, Ulrich A.; Schöppner, Nicole; Trautmann, Christina; Severin, Daniel; Romanenko, Anton; Hubert, Christian

    2015-12-01

    A new on-line Raman System, which was installed at the M3-beamline at the UNILAC, GSI Helmholtzzentrum für Schwerionenforschung Darmstadt was used for first "in situ" spectroscopic measurements. Calcite and malachite samples were irradiated in steps between 1 × 109 and 1 × 1012 ions/cm2 with Au ions (calcite) and Xe ions (malachite) at an energy of 4.8 MeV/u. After irradiation, calcite revealed a new Raman band at 437 cm-1 and change of the full width at half maximum for the 1087 cm-1 Raman band. The Raman bands of malachite change significantly with increasing fluence. Up to a fluence of 7 × 1010 ions/cm2, all existing bands decrease in intensity. Between 8 × 1010 and 1 × 1011 ions/cm2 a broad Cu2O band between 110 and 220 cm-1 occurs, which superimposes the pre-existing Raman bands. Additionally, a new broad band between 1000 and 1750 cm-1 is formed, which is interpreted as a carbon coating. In contrast to the Cu2O band, the carbon band vanished when further irradiating the sample. The installations as well as first in situ measurements at room temperature are presented.

  3. Trace determination of antibacterial pharmaceuticals in fishes by microwave-assisted extraction and solid-phase purification combined with dispersive liquid-liquid microextraction followed by ultra-high performance liquid chromatography-tandem mass spectrometry.

    PubMed

    Huang, Peiting; Zhao, Pan; Dai, Xinpeng; Hou, Xiaohong; Zhao, Longshan; Liang, Ning

    2016-02-01

    A novel pretreatment method involving microwave-assisted extraction and solid-phase purification combined with dispersive liquid-liquid microextraction (MAE-SPP-DLLME) followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was established for the simultaneous determination of six antibacterial pharmaceuticals including metronidazole, tinidazole, chloramphenicol, thiamphenicol, malachite green and crystal violet. The conditions of MAE were optimized using an orthogonal design and the optimal conditions were found to be 8mL for acetonitrile, 50°C for 5min. Then, neutral alumina column was employed in the solid-phase purification. Finally, the critical parameters affecting DLLME, including selection of extraction and dispersive solvent, adjustment of pH, salt concentration, extraction time, were investigated by single factor study. Under optimum conditions, good linearities (r>0.9991) and satisfied recoveries (Recoveries>87.0%, relative standard deviation (RSD)<6.3%) were observed for all of the target analytes. The limits of detection and quantification were 4.54-101.3pgkg(-1) and 18.02-349.1pgkg(-1), respectively. Intra-day and inter-day RSDs were all lower than 3.6%. An obvious reduction in matrix effect was observed by this method compared with microwave assisted extraction followed by purification. The established method was sensitive, rapid, accurate and employable to simultaneously determine target analytes in farmed fish, river fish and marine fish.

  4. Development and validation of a fast monoclonal based disequilibrium enzyme-linked immunosorbent assay for the detection of triphenylmethane dyes and their metabolites in fish.

    PubMed

    Oplatowska, Michalina; Connolly, Lisa; Stevenson, Paul; Stead, Sara; Elliott, Christopher T

    2011-07-18

    Malachite Green (MG), Crystal Violet (CV) and Brilliant Green (BG) are antibacterial, antifungal and antiparasitic agents that have been used for treatment and prevention of diseases in fish. These dyes are metabolized into reduced leuco forms (LMG, LCV, LBG) that can be present in fish muscles for a long period. Due to the carcinogenic properties they are banned for use in fish for human consumption in many countries including the European Union and the United States. HPLC and LC-MS techniques are generally used for the detection of these compounds and their metabolites in fish. This study presents the development of a fast enzyme-linked immunosorbent assay (ELISA) method as an alternative for screening purposes. A first monoclonal cell line producing antibodies to MG was generated using a hybridoma technique. The antibody had good cross-reactivates with related chromatic forms of triphenylmethane dyes such as CV, BG, Methyl Green, Methyl Violet and Victoria Blue R. The monoclonal antibody (mAb) was used to develop a fast (20 min) disequilibrium ELISA screening method for the detection of triphenylmethanes in fish. By introducing an oxidation step with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) during sample extraction the assay was also used to detect the presence of the reduced metabolites of triphenylmethanes. The detection capability of the assay was 1 ng g(-1) for MG, LMG, CV, LCV and BG which was below the minimum required performance limit (MRPL) for the detection method of total MG (sum of MG and LMG) set by the Commission Decision 2004/25/EC (2 ng g(-1)). The mean recoveries for fish samples spiked at 0.5 MRPL and MRPL levels with MG and LMG were between 74.9 and 117.0% and inter- and intra-assay coefficients of variation between 4.7 and 25.7%. The validated method allows the analysis of a batch of 20 samples in two to three hours. Additionally, this procedure is substantially faster than other ELISA methods developed for MG/LMG thus far. The stable

  5. 75 FR 19994 - Green Diamond Resource Company, California Timberlands Division, Forest Management Habitat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-16

    ... Fish and Wildlife Service Green Diamond Resource Company, California Timberlands Division, Forest...) regarding an expected application from the Green Diamond Resource Company, California Timberlands Division (Green Diamond), for an incidental take permit (ITP, or permit) authorizing incidental take of...

  6. Brooklyn Green, North Green, South Green, & West Green, parts ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Brooklyn Green, North Green, South Green, & West Green, parts of Brown Road, Canterbury Road (Route 169), Hartford Road (Route 6), Hyde Road, Pomfret Road (Route 169), Prince Hill Road, Providence Road (Route 6), Wauregan Road (Routes 169 & 205), & Wolf Den Road, Brooklyn, Windham County, CT

  7. One-step green synthesis of high uniform SERS substrate based on Au nanoparticles grown on Ge wafer

    NASA Astrophysics Data System (ADS)

    Zhou, Juhong; Zhu, Feng; Wang, Yan; Wang, Tao

    2015-05-01

    Highly sensitive, large-area and uniform surface-enhanced Raman scattering (SERS) substrates based on gold nanoparticles grown on Ge wafer have been fabricated by a one-step green reaction. The results showed that these substrates exhibited admirable performance in the low concentration detection (1 × 10-7 M) of Rhodamine 6G with the enhancement factor of 4.5 × 106 and remarkable uniformity with relative standard deviation less than 8%. The uniform enhancement was also obtained in the aqueous detection of malachite green. During the experiments, the Raman spectra were recorded in the solution to pursue the uniformity, reproducibility and stability of signals.

  8. One Fish Two Fish.

    ERIC Educational Resources Information Center

    Hoffman, Michele

    1998-01-01

    This activity explains fisheries resource management to seven-year olds. First-grade students learn concepts such as offspring viability, life expectancy, and distribution of species, which help to determine when, where, and how people fish and the importance of fishing responsibly. Lists materials, procedures, and extensions. (SJR)

  9. Determination of brilliant green from fish pond water using carbon nanotube assisted pseudo-stir bar solid/liquid microextraction combined with UV-vis spectroscopy-diode array detection

    NASA Astrophysics Data System (ADS)

    Es'haghi, Zarrin; Khooni, Maliheh Ahmadi-Kalateh; Heidari, Tahereh

    2011-08-01

    This paper describes the development of a new design of hollow fiber solid/liquid phase microextraction (HF-SLPME) for determination of brilliant green (BG) residues in water fish ponds. This method consists of an aqueous donor phase and carbon nanotube reinforced organic solvent (acceptor phase) operated in direct immersion sampling mode. The multi-walled carbon nanotube dispersed in the organic solvent is held in the pores and lumen of a porous polypropylene hollow fiber. It is in contact directly with the aqueous donor phase. In this method the solid/liquid extractor phase is supported using a polypropylene hollow fiber membrane. Both ends of the hollow fiber segment are sealed with magnetic stoppers. This device is placed inside the donor solution and plays the rule of a pseudo-stir bar. It is disposable, so single use of the fiber reduces the risk of carry-over problems. Brilliant green (BG) after extraction from the aqueous samples with mentioned HF-SLPME device was determined by ultraviolet-visible spectroscopy with diode array detection (UV-vis/DAD). The absorption wavelength was set to 625 nm ( λmax). The effect of different variables on the extraction was evaluated and optimized to enhance the sensitivity and extraction efficiency of the proposed method. The calibration curve was linear in the range of 1.00-10,000 μg L -1 of BG in the initial solution with R2 = 0.979. Detection limit, based on three times the standard deviation of the blank, was 0.55 μg L -1. All experiments were carried out at room temperature (25 ± 0.5 °C).

  10. Spin gap in malachite Cu2(OH)2CO3 and its evolution under pressure

    NASA Astrophysics Data System (ADS)

    Lebernegg, Stefan; Tsirlin, Alexander A.; Janson, Oleg; Rosner, Helge

    2013-12-01

    We report on the microscopic magnetic modeling of the spin-(1)/(2) copper mineral malachite at ambient and elevated pressures. Despite the layered crystal structure of this mineral, the ambient-pressure susceptibility and magnetization data can be well described by an unfrustrated quasi-one-dimensional magnetic model. Weakly interacting antiferromagnetic alternating spin chains are responsible for a large spin gap of 120 K. Although the intradimer Cu-O-Cu bridging angles are considerably smaller than the interdimer angles, density functional theory (DFT) calculations revealed that the largest exchange coupling of 190 K operates within the structural dimers. The lack of the inversion symmetry in the exchange pathways gives rise to sizable Dzyaloshinskii-Moriya interactions which were estimated by full-relativistic DFT+U calculations. Based on available high-pressure crystal structures, we investigate the exchange couplings under pressure and make predictions for the evolution of the spin gap. The calculations evidence that intradimer couplings are strongly pressure dependent and their evolution underlies the decrease of the spin gap under pressure. Finally, we assess the accuracy of hydrogen positions determined by structural relaxation within DFT and put forward this computational method as a viable alternative to elaborate experiments.

  11. Sugar digestion efficiencies of Gurney's sugarbirds, malachite sunbirds, and black sunbirds.

    PubMed

    Downs, C T

    1997-01-01

    This study determined the interaction between energy assimilation and digestive constraints on the foraging behaviour of nectarivorous Gurney's sugarbirds (Promerops gurneyi), black sunbirds (Nectarinia amethystina), and malachite sunbirds (Nectarinia famosa) in the laboratory. Rates of sugar intake and consumption, transit time, and the concentration of sugar in the excreta were measured when birds were fed 0.25 mol L-1 sucrose, 0.73 mol L-1 sucrose, and 0.73 mol L-1 glucose. For each species, intake rates by volume were greater at low sugar concentrations, such that energy intakes per 90 min were similar, irrespective of diet, which supports the idea of regulated energy intake for these nectarivorous birds. All species were efficient at energy extraction, excreting 1% or less sucrose equivalent irrespective of the initial sugar concentration of each diet. Transit times of solutions ingested increased with an increase in sugar concentration. Birds maximized energy assimilation on high- and low-energy nectar diets by having high extraction efficiencies and short transit times. Sugarbird and sunbird foraging behaviours may be limited by digestive processes and the cost of carrying high-energy reserves as nectar sugar concentration increases.

  12. Analysis of mutations and bone marrow micronuclei in Big Blue rats fed leucomalachite green.

    PubMed

    Manjanatha, M G; Shelton, S D; Bishop, M; Shaddock, J G; Dobrovolsky, V N; Heflich, R H; Webb, P J; Blankenship, L R; Beland, F A; Greenlees, K J; Culp, S J

    2004-03-22

    Leucomalachite green (LMG) is the major metabolite of malachite green (MG), a triphenylmethane dye that has been used widely as an antifungal agent in the fish industry. Concern over MG and LMG is due to the potential for consumer exposure, suggestive evidence of tumor promotion in rodent liver, and suspicion of carcinogenicity based on structure-activity relationships. In order to evaluate the risks associated with exposure to LMG, female Big Blue rats were fed up to 543 ppm LMG; groups of these rats were killed after 4, 16, or 32 weeks of exposure and evaluated for genotoxicity. We previously reported that this treatment resulted in a dose-dependent induction of liver DNA adducts, and that the liver lacI mutant frequency (MF) was increased, but only in rats fed 543 ppm LMG for 16 weeks. In the present study, we report the results from lymphocyte Hprt mutant assays and bone marrow micronucleus assays performed on these same rats. In addition, we have determined the types of lacI mutations induced in the rats fed 543 ppm LMG for 16 weeks and the rats fed control diet. No significant increases in the frequency of micronuclei or Hprt mutants were observed for any of the doses or time points assayed. Molecular analysis of 80 liver lacI mutants from rats fed 543 ppm LMG for 16 weeks revealed that 21% (17/80) were clonal in origin and that most (55/63) of the independent mutations were base pair substitutions. The predominant type of mutation was G:C --> A:T transition (31/63) and the majority (68%) of these involved CpG sites. When corrected for clonality, the 16-week lacI mutation frequency (36 +/- 10) x 10(-6) in treated rats was not significantly different from the clonally corrected control frequency (17 +/- 9 x 10(-6); P = 0.06). Furthermore, the lacI mutational spectrum in treated rats was not significantly different from that found for control rats (P = 0.09). Taken together, these data indicate that the DNA adducts produced by LMG in female rats do not result

  13. Fish Allergy

    MedlinePlus

    ... can react to touching fish or breathing in vapors from cooking fish. A fish allergy can cause ... hives red spots swelling a drop in blood pressure , causing lightheadedness or loss of consciousness Your child ...

  14. Fish Hearing.

    ERIC Educational Resources Information Center

    Blaxter, J. H. S.

    1980-01-01

    Provides related information about hearing in fish, including the sensory stimulus of sound in the underwater environment, mechanoreceptors in fish, pressure perception and the swimbladder, specializations in sound conduction peculiar to certain fish families. Includes numerous figures. (CS)

  15. Synthesis of malachite@clay nanocomposite for rapid scavenging of cationic and anionic dyes from synthetic wastewater.

    PubMed

    Srivastava, Varsha; Sillanpää, Mika

    2017-01-01

    Synthesis of malachite@clay nanocomposite was successfully carried out for the removal of cationic (Methylene Blue, MB) and anionic dyes (Congo Red, CR) from synthetic wastewater. Nanocomposite was characterized by TEM, SEM, FT-IR, EDS analysis and zeta potential. TEM analysis indicated that the particle diameter of nanocomposite was in the range of 14 to 23nm. Various important parameters viz. contact time, concentration of dyes, nanocomposite dosage, temperature and solution pH were optimized to achieve maximum adsorption capacity. In the case of MB, removal decreased from 99.82% to 93.67% while for CR, removal decreased from 88.55% to 75.69% on increasing dye concentration from 100 to 450mg/L. pH study confirmed the higher removal of CR in acidic range while MB removal was higher in alkaline range. Kinetic study revealed the applicability of pseudo-second-order model for the adsorption of both dyes. Negative values of ΔG(0) for both systems suggested the feasibility of dye removal and support for spontaneous adsorption of CR and MB on nanocomposite. Nanocomposite showed 277.77 and 238.09mg/g Langmuir adsorption capacity for MB and CR respectively. Desorption of dyes from the dye loaded nanocomposite was easily carried out with acetone. The results indicate that the prepared malachite@clay nanocomposite is an efficient adsorbent with high adsorption capacity for the aforementioned dyes.

  16. Antarctic Fishes.

    ERIC Educational Resources Information Center

    Eastman, Joseph T.; DeVries, Arthur L.

    1986-01-01

    Explains the adaptations to Antarctic waters that Notothenioidei, a group of advanced bony fishes, have exhibited. Discusses the fishes' mechanisms of production of antifreeze properties and their capacities for neutral buoyancy in water. (ML)

  17. Fish Dishes.

    ERIC Educational Resources Information Center

    Derby, Marie

    2003-01-01

    Describes an art project that was inspired by Greek pottery, specifically dishes shaped as fish. Explains that fourth-grade students drew a fish shape that was later used to create their clay version of the fish. Discusses how the students examined the pottery to make decisions about color and design. (CMK)

  18. Green Engineering

    EPA Pesticide Factsheets

    Green Engineering is the design, commercialization and use of processes and products that are feasible and economical while reducing the generation of pollution at the source and minimizing the risk to human health and the environment.

  19. Green Roofs

    SciTech Connect

    2004-08-01

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  20. Green Giant.

    ERIC Educational Resources Information Center

    Polo, Marco

    2003-01-01

    Details the design of the Bahen Centre for Information Technology at the University of Toronto, particularly its emphasis on "green," or sustainable, design. Includes floor plans and photographs. (EV)

  1. Code Green.

    ERIC Educational Resources Information Center

    McMinn, John

    2002-01-01

    Assesses the integrated approach to green design in the new Computer Science Building at Toronto's York University. The building design fulfills the university's demand to combine an energy efficient design with sustainability. Floor and site plans are included. (GR)

  2. Green Infrastructure

    EPA Science Inventory

    Large paved surfaces keep rain from infiltrating the soil and recharging groundwater supplies. Alternatively, Green infrastructure uses natural processes to reduce and treat stormwater in place by soaking up and storing water. These systems provide many environmental, social, an...

  3. Evaluation of continuous 4 day exposure to peracetic acid as a treatment for Ichthyophthirius multifiliis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The parasitic ciliate Ichthyophthirius multifiliis infests all species of freshwater fish and can cause severe economic losses in fish breeding. The most effective treatment, malachite green, has been banned in Europe and North America for use in food-fish production. Peracetic acid (PAA) was foun...

  4. Clotrimazole as a Potent Agent for Treating the Oomycete Fish Pathogen Saprolegnia parasitica through Inhibition of Sterol 14α-Demethylase (CYP51)

    PubMed Central

    Warrilow, Andrew G. S.; Hull, Claire M.; Rolley, Nicola J.; Parker, Josie E.; Nes, W. David; Smith, Stephen N.

    2014-01-01

    A candidate CYP51 gene encoding sterol 14α-demethylase from the fish oomycete pathogen Saprolegnia parasitica (SpCYP51) was identified based on conserved CYP51 residues among CYPs in the genome. It was heterologously expressed in Escherichia coli, purified, and characterized. Lanosterol, eburicol, and obtusifoliol bound to purified SpCYP51 with similar binding affinities (Ks, 3 to 5 μM). Eight pharmaceutical and six agricultural azole antifungal agents bound tightly to SpCYP51, with posaconazole displaying the highest apparent affinity (Kd, ≤3 nM) and prothioconazole-desthio the lowest (Kd, ∼51 nM). The efficaciousness of azole antifungals as SpCYP51 inhibitors was confirmed by 50% inhibitory concentrations (IC50s) of 0.17 to 2.27 μM using CYP51 reconstitution assays. However, most azole antifungal agents were less effective at inhibiting S. parasitica, Saprolegnia diclina, and Saprolegnia ferax growth. Epoxiconazole, fluconazole, itraconazole, and posaconazole failed to inhibit Saprolegnia growth (MIC100, >256 μg ml−1). The remaining azoles inhibited Saprolegnia growth only at elevated concentrations (MIC100 [the lowest antifungal concentration at which growth remained completely inhibited after 72 h at 20°C], 16 to 64 μg ml−1) with the exception of clotrimazole, which was as potent as malachite green (MIC100, ∼1 μg ml−1). Sterol profiles of azole-treated Saprolegnia species confirmed that endogenous CYP51 enzymes were being inhibited with the accumulation of lanosterol in the sterol fraction. The effectiveness of clotrimazole against SpCYP51 activity (IC50, ∼1 μM) and the concentration inhibiting the growth of Saprolegnia species in vitro (MIC100, ∼1 to 2 μg ml−1) suggest that clotrimazole could be used against Saprolegnia infections, including as a preventative measure by pretreatment of fish eggs, and for freshwater-farmed fish as well as in leisure activities. PMID:25085484

  5. Fish Rhabdoviruses

    USGS Publications Warehouse

    Kurath, G.; Winton, J.

    2008-01-01

    Many important viral pathogens of fish are members of the family Rhabdoviridae. The viruses in this large group cause significant losses in populations of wild fish as well as among fish reared in aquaculture. Fish rhabdoviruses often have a wide host and geographic range, and infect aquatic animals in both freshwater and seawater. The fish rhabdoviruses comprise a diverse collection of isolates that can be placed in one of two quite different groups: isolates that are members of the established genusNovirhabdovirus, and those that are most similar to members of the genus Vesiculovirus. Because the diseases caused by fish rhabdoviruses are important to aquaculture, diagnostic methods for their detection and identification are well established. In addition to regulations designed to reduce the spread of fish viruses, a significant body of research has addressed methods for the control or prevention of diseases caused by fish rhabdoviruses, including vaccination. The number of reported fish rhabdoviruses continues to grow as a result of the expansion of aquaculture, the increase in global trade, the development of improved diagnostic methods, and heightened surveillance activities. Fish rhabdoviruses serve as useful components of model systems to study vertebrate virus disease, epidemiology, and immunology.

  6. Green Power Partnership Videos

    EPA Pesticide Factsheets

    The Green Power Partnership develops videos on a regular basis that explore a variety of topics including, Green Power partnership, green power purchasing, Renewable energy certificates, among others.

  7. Green pioneers.

    PubMed

    Trueland, Jennifer

    The government has set tough targets for the NHS in England to reduce its carbon footprint. In this article, nurses and managers at Nottinghamshire Healthcare NHS Trust explain how a programme of 'greening' initiatives - including a trial of electric cars for community staff - have slashed the trust's CO2 output.

  8. Going Green

    ERIC Educational Resources Information Center

    Witkowsky, Kathy

    2009-01-01

    Going green saves money and can even make money. Sustainable practices promote better health, less absenteeism, and more productivity. They also attract students, who are paying increasing attention to schools' environmental policies. Beyond being the smart thing to do, administrators at the University of Washington say repeatedly, it's the right…

  9. Green Leaders

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2008-01-01

    More and more people are viewing the world through green-tinted glasses, and those ideas about making school and university facilities more environmentally friendly suddenly are appearing to be prudent and responsible. Among the groups that have been advocating for environmentally friendly school design for years are the Collaborative for High…

  10. Think green.

    PubMed

    Serb, Chris

    2008-08-01

    Hospitals typically don't come to mind when you think about cutting-edge environmental programs, but that's changing. Rising energy costs, the need to replace older facilities, and a growing environmental consciousness have spurred hospitals nationwide to embrace a green ideology. The executive suite is a vocal and active player in these efforts.

  11. Buying Green

    ERIC Educational Resources Information Center

    Layng, T. V. Joe

    2010-01-01

    In "Buying Green," Joe Layng recognizes that, like all choices we make, our decisions as consumers are more likely to be influenced by their short-term consequences for us as individuals (price, quality) than they are by their long-term consequences for society (environmental impact). He believes that the equation can be tilted in favor of greener…

  12. Green Power

    ERIC Educational Resources Information Center

    Schaffhauser, Dian

    2009-01-01

    In the world of higher education, even the most ambitious sustainability plans often begin with tiny steps taken by individual departments. Michael Crowley, a program manager for Environmental Health & Engineering (EH&E) and former assistant director of the Harvard (Massachusetts) Green Campus Initiative, explains that going for small wins through…

  13. Texture Fish

    ERIC Educational Resources Information Center

    Stone, Julie

    2007-01-01

    In an effort to provide an opportunity for her first graders to explore texture through an engaging subject, the author developed a three-part lesson that features fish in a mixed-media artwork: (1) Exploring Textured Paint; (2) Creating the Fish; and (3) Role Playing. In this lesson, students effectively explore texture through painting, drawing,…

  14. Analysis of green copper pigments in illuminated manuscripts by micro-Raman spectroscopy.

    PubMed

    Gilbert, B; Denoël, S; Weber, G; Allart, D

    2003-10-01

    In the majority of the literature describing green coloured materials used on ancient painting layers (15th or 16th century), two copper greens are mainly cited: malachite [CuCOr3 x Cu(OH)2] and verdigris [Cu(CH3COO)2 x [Cu(OH)2]3 x 2H2O]. It is shown, by micro-Raman spectroscopy, that the artists were actually employing more than these two copper greens, in particular various copper sulfates, among which the most common pigment found is posnjakite [CuSO4 x 3Cu(OH)2 x H2O]. In contrast to the PIXE (particle induced X-ray emission) technique, Raman spectroscopy is a technique of choice, able to distinguish not only a copper sulfate from a carbonate or acetate but also the different sulfates themselves; in this respect, we found that the high wavenumber region (2800-4000 cm(-1)), characteristic of H2O vibrations, is of particular interest. It is also shown that numerous green areas were created with mixtures of a copper sulfate mixed with other pigments, for instance to enhance the colour depth. Finally, in some cases, no green pigment is actually employed but the colour is obtained by intimately mixing yellow and blue pigments. All these results led to a new look at the pigments which were in use on the palettes of the ancient artists.

  15. One Fish, Two Fish, Redfish, You Fish!

    ERIC Educational Resources Information Center

    White, Katherine; Timmons, Maryellen; Medders, Paul

    2011-01-01

    The recreational fishing activity presented in this article provides a hands-on, problem-based experience for students; it unites biology, math, economics, environmental policy, and population dynamics concepts. In addition, the activity allows students to shape environmental policy in a realistic setting and evaluate their peers' work. By…

  16. Genomics and Mapping of Teleostei (Bony Fish)

    PubMed Central

    2003-01-01

    Until recently, the Human Genome Project held centre stage in the press releases concerning sequencing programmes. However, in October 2001, it was announced that the Japanese puffer fish (Takifugu rubripes, Fugu) was the second vertebrate organism to be sequenced to draft quality. Briefly, the spotlight was on fish genomes. There are currently two other fish species undergoing intensive sequencing, the green spotted puffer fish (Tetraodon nigroviridis) and the zebrafish (Danio rerio). But this trio are, in many ways, atypical representations of the current state of fish genomic research. The aim of this brief review is to demonstrate the complexity of fish as a group of vertebrates and to publicize the ‘lesser-known’ species, all of which have something to offer. PMID:18629122

  17. Fishing Forecasts

    NASA Technical Reports Server (NTRS)

    1988-01-01

    ROFFS stands for Roffer's Ocean Fishing Forecasting Service, Inc. Roffer combines satellite and computer technology with oceanographic information from several sources to produce frequently updated charts sometimes as often as 30 times a day showing clues to the location of marlin, sailfish, tuna, swordfish and a variety of other types. Also provides customized forecasts for racing boats and the shipping industry along with seasonal forecasts that allow the marine industry to formulate fishing strategies based on foreknowledge of the arrival and departure times of different fish. Roffs service exemplifies the potential for benefits to marine industries from satellite observations. Most notable results are reduced search time and substantial fuel savings.

  18. EVALUATION OF FISH SAMPLING DESIGNS FOR COASTAL WETLANDS

    EPA Science Inventory

    Because no objective assessment of fish sampling methodologies has been completed for Great Lakes coastal wetlands we evaluated catches from several techniques and studies to determine the most effecive combinations for these habitats. Data from six underdeveloped sites in Green ...

  19. EVALUATION OF FISH SAMPLING DESIGNS FOR COASTAL WATERS

    EPA Science Inventory

    Because no objective assessment of fish sampling methodologies has been completed for Great Lakes coastal wetlands we evaluated catches from several techniques and studies to determine the most effective combinations for these habitats. Data from six underdeveloped sites in Green...

  20. Fish Allergy

    MedlinePlus

    ... been diagnosed with a fish allergy, keep injectable epinephrine on hand in case of a severe reaction. ... mouth or throat or difficulty breathing, give the epinephrine auto-injector right away. Every second counts in ...

  1. Designer Fish.

    ERIC Educational Resources Information Center

    Hall, William R., Jr.

    1990-01-01

    Described is an activity in which students are asked to design a fish that would survive in a natural system. A project to computerize the activity is discussed. The development of this artificial intelligence software is detailed. (CW)

  2. Fish Facts

    MedlinePlus

    ... not eat any fish because they worry about mercury in seafood. Mercury is a metal that, at high levels, can ... many types of seafood have little or no mercury at all. So your risk of mercury exposure ...

  3. Fighting fish

    NASA Astrophysics Data System (ADS)

    Duchi, E.; Guerrini, V.; Rinaldi, S.; Schaeffer, G.

    2017-01-01

    We introduce new combinatorial structures, called fighting fish, that generalize directed convex polyominoes by allowing them to branch out of the plane into independent substructures. On the one hand the combinatorial structure of fighting fish appears to be particularly rich: we show that their generating function with respect to the perimeter and number of tails is algebraic, and we conjecture a mysterious multivariate equidistribution property with the left ternary trees introduced by Del Lungo et al On the other hand, fighting fish provide a simple and natural model of random branching surfaces which displays original features: in particular, we show that the average area of a uniform random fighting fish with perimeter 2n is of order n 5/4: to the best of our knowledge this behaviour is non-standard and suggests that we have identified a new universality class of random structures. Dedicated to Tony Guttmann on the occasion of his 70th birthday.

  4. Spectral and spatial selectivity of luminance vision in reef fish.

    PubMed

    Siebeck, Ulrike E; Wallis, Guy Michael; Litherland, Lenore; Ganeshina, Olga; Vorobyev, Misha

    2014-01-01

    Luminance vision has high spatial resolution and is used for form vision and texture discrimination. In humans, birds and bees luminance channel is spectrally selective-it depends on the signals of the long-wavelength sensitive photoreceptors (bees) or on the sum of long- and middle-wavelength sensitive cones (humans), but not on the signal of the short-wavelength sensitive (blue) photoreceptors. The reasons of such selectivity are not fully understood. The aim of this study is to reveal the inputs of cone signals to high resolution luminance vision in reef fish. Sixteen freshly caught damselfish, Pomacentrus amboinensis, were trained to discriminate stimuli differing either in their color or in their fine patterns (stripes vs. cheques). Three colors ("bright green", "dark green" and "blue") were used to create two sets of color and two sets of pattern stimuli. The "bright green" and "dark green" were similar in their chromatic properties for fish, but differed in their lightness; the "dark green" differed from "blue" in the signal for the blue cone, but yielded similar signals in the long-wavelength and middle-wavelength cones. Fish easily learned to discriminate "bright green" from "dark green" and "dark green" from "blue" stimuli. Fish also could discriminate the fine patterns created from "dark green" and "bright green". However, fish failed to discriminate fine patterns created from "blue" and "dark green" colors, i.e., the colors that provided contrast for the blue-sensitive photoreceptor, but not for the long-wavelength sensitive one. High resolution luminance vision in damselfish, Pomacentrus amboinensis, does not have input from the blue-sensitive cone, which may indicate that the spectral selectivity of luminance channel is a general feature of visual processing in both aquatic and terrestrial animals.

  5. Green Manufacturing

    SciTech Connect

    Patten, John

    2013-12-31

    Green Manufacturing Initiative (GMI): The initiative provides a conduit between the university and industry to facilitate cooperative research programs of mutual interest to support green (sustainable) goals and efforts. In addition to the operational savings that greener practices can bring, emerging market demands and governmental regulations are making the move to sustainable manufacturing a necessity for success. The funding supports collaborative activities among universities such as the University of Michigan, Michigan State University and Purdue University and among 40 companies to enhance economic and workforce development and provide the potential of technology transfer. WMU participants in the GMI activities included 20 faculty, over 25 students and many staff from across the College of Engineering and Applied Sciences; the College of Arts and Sciences' departments of Chemistry, Physics, Biology and Geology; the College of Business; the Environmental Research Institute; and the Environmental Studies Program. Many outside organizations also contribute to the GMI's success, including Southwest Michigan First; The Right Place of Grand Rapids, MI; Michigan Department of Environmental Quality; the Michigan Department of Energy, Labor and Economic Growth; and the Michigan Manufacturers Technical Center.

  6. Green synthesis of iron nanoparticles by various tea extracts: comparative study of the reactivity.

    PubMed

    Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-09-15

    Iron nanoparticles (Fe NPs) are often synthesized using sodium borohydride with aggregation, which is a high cost process and environmentally toxic. To address these issues, Fe NPs were synthesized using green methods based on tea extracts, including green, oolong and black teas. The best method for degrading malachite green (MG) was Fe NPs synthesized by green tea extracts because it contains a high concentration of caffeine/polyphenols which act as both reducing and capping agents in the synthesis of Fe NPs. These characteristics were confirmed by a scanning electron microscope (SEM), UV-visible (UV-vis) and specific surface area (BET). To understand the formation of Fe NPs using various tea extracts, the synthesized Fe NPs were characterized by SEM, X-ray energy-dispersive spectrometer (EDS), and X-ray diffraction (XRD). What emerged were different sizes and concentrations of Fe NPs being synthesized by tea extracts, leading to various degradations of MG. Furthermore, kinetics for the degradation of MG using these Fe NPs fitted well to the pseudo first-order reaction kinetics model with more than 20 kJ/mol activation energy, suggesting a chemically diffusion-controlled reaction. The degradation mechanism using these Fe NPs included adsorption of MG to Fe NPs, oxidation of iron, and cleaving the bond that was connected to the benzene ring.

  7. Green synthesis of iron nanoparticles by various tea extracts: Comparative study of the reactivity

    NASA Astrophysics Data System (ADS)

    Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-09-01

    Iron nanoparticles (Fe NPs) are often synthesized using sodium borohydride with aggregation, which is a high cost process and environmentally toxic. To address these issues, Fe NPs were synthesized using green methods based on tea extracts, including green, oolong and black teas. The best method for degrading malachite green (MG) was Fe NPs synthesized by green tea extracts because it contains a high concentration of caffeine/polyphenols which act as both reducing and capping agents in the synthesis of Fe NPs. These characteristics were confirmed by a scanning electron microscope (SEM), UV-visible (UV-vis) and specific surface area (BET). To understand the formation of Fe NPs using various tea extracts, the synthesized Fe NPs were characterized by SEM, X-ray energy-dispersive spectrometer (EDS), and X-ray diffraction (XRD). What emerged were different sizes and concentrations of Fe NPs being synthesized by tea extracts, leading to various degradations of MG. Furthermore, kinetics for the degradation of MG using these Fe NPs fitted well to the pseudo first-order reaction kinetics model with more than 20 kJ/mol activation energy, suggesting a chemically diffusion-controlled reaction. The degradation mechanism using these Fe NPs included adsorption of MG to Fe NPs, oxidation of iron, and cleaving the bond that was connected to the benzene ring.

  8. A simple experiment that demonstrates the ``green flash''

    NASA Astrophysics Data System (ADS)

    Courtial, Johannes

    2012-11-01

    The green flash occurs when, under certain atmospheric conditions, the top segment of the low sun is visibly green. It is surrounded—in at least a few minds—by an air of mystery. I describe a simple experiment that demonstrates different aspects of the green flash. The experiment uses an odd-shaped, water-filled, fish tank to simulate the refractive properties of the atmosphere; milk powder added to the water mimicks the atmosphere's scattering properties. A circular white-light source is viewed through the fish tank and the combination of refraction and scattering makes one end of the light source look green. The setup also allows experimentation with mirage effects, thereby drawing attention to their often neglected contribution to the green flash.

  9. Green Power Partner Resources

    EPA Pesticide Factsheets

    EPA Green Power Partners can access tools and resources to help promote their green power commitments. Partners use these tools to communicate the benefits of their green power use to their customers, stakeholders, and the general public.

  10. Green Power Community News

    EPA Pesticide Factsheets

    This page features news about EPA's Green Power Communities. GPCs are a subset of the Green Power Partnership; municipalities or tribal governments where government, businesses, and residents collectively use enough green power to meet GPP requirements.

  11. Green Vehicle Guide

    MedlinePlus

    ... United States Environmental Protection Agency Search Search Green Vehicle Guide Share Facebook Twitter Google+ Pinterest Contact Us ... your needs. Search for a SmartWay Vehicle Green Vehicle Guide ​What is a green vehicle? Alternative fuels ...

  12. Karuk Fishing.

    ERIC Educational Resources Information Center

    Bennett, Ruth, Ed.; Goodwin, Norman

    A booklet on traditional fishing practices of the Karuk Indians of northwestern California is presented in the formal, literary English speech of Norman Goodwin, a Karuk medicine man involved in preserving ancient tribal traditions. Empirical information and personal narratives are combined in descriptions of different kinds of nets, social rules…

  13. Gone Fishing.

    ERIC Educational Resources Information Center

    Olson-Demme, Hillary; Kisiel, Jim

    2003-01-01

    Presents a hands-on activity in which students create a model of an ocean ecosystem to gain an understanding of how humans can alter biodiversity through their actions. Uses differing levels of fishing technology to explore the concepts of sustainability and overfishing. (Author/SOE)

  14. Commercial Fishing.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee. Div. of Vocational Education.

    This document is a curriculum framework for a program in commercial fishing to be taught in Florida secondary and postsecondary institutions. This outline covers the major concepts/content of the program, which is designed to prepare students for employment in occupations with titles such as net fishers, pot fishers, line fishers, shrimp boat…

  15. [Spectral analysis of green pigments of painting and colored drawing in northern Chinese ancient architectures].

    PubMed

    Wang, Li-Qin; Yan, Jing; Fan, Xiao-Lei; Ma, Tao

    2010-02-01

    It is important to identify pigments of painting and colored drawing in ancient architectures in order to restore and conserve them. The components of green pigments were detected with X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy-energy dispersive X-ray (SEM-EDX). Twenty-seven samples were collected from painting and colored drawing in northern Chinese ancient architectures in Beijing, Shanxi province and Gansu province. The experiment results showed that emerald green [CuCH3COO]2 x Cu(AsO2)2], a complex of copper aceto-arsenite pigment, had been used as the colored component in fifteen samples, whereas organic materials synthesized in the rest. However, in all samples there were no malachite and atacamite, green pigments commonly used in ancient time a long time ago. These two pigments have been found in Qin Shihuang's Terracotta Army and the wall paintings at Mogao Grettoes, Dunhuang, and some other famous wall paintings and color pottery figurines. However, emerald green was used many years later. It was reported that emerald green was synthesized by Germany in 1814 and had been widely used in China as watercolor on pith paper works and on scroll paintings since the 1850s. Because painting and colored drawing in ancient architectures stands outside, under sunlight and rain, it must be repaired and repainted in less than fifty years. Therefore, it is not surprising that emerald green was used in them. In recent years, artificial organic materials are increasingly used in painting and colored drawing in ancient architectures. From experiments it was also showed that in the same recolored painting and colored drawing, organic materials are usually in the later layers, but emerald green is in the earlier layers. This work supplies a lot of data for the purpose of selecting restoration materials and identifying painting and colored drawing in ancient architectures with a new method.

  16. Ab Initio Thermodynamics and the Relationship between Octahedral Distortion, Lattice Structure, and Proton Substitution Defects in Malachite/Rosasite Group Endmember Pokrovskite Mg2CO3(OH)2.

    PubMed

    Chaka, Anne M

    2016-12-29

    Divalent metal hydroxycarbonates with M2CO3(OH)2 stoichiometry are widely used in industry and are abundant in nature as the malachite/rosasite group of minerals. Essential to their performance as catalytic precursors and in nanoelectronics, these materials and minerals exhibit a high degree of cation ordering in mixed metal systems due to differences in distortion of the octahedral metal sites. Density-functional theory (DFT) calculations on pokrovskite Mg2CO3(OH)2 in the rosasite structure and Mg analogues of monoclinic and orthorhombic forms of malachite determine that the octahedral sites are innately distorted, and that d(9) Cu(II) Jahn-Teller distortion accommodates this distortion rather than causes it, leading to the significant preference of Cu for the type I octahedral sites. This distortion also leads to a high propensity for formation of cation vacancies charge balanced by proton substitution. Ab initio thermodynamics is used to determine that there are conditions under which proton substitution defects are slightly more stable than the stoichiometric structure, consistent with the widespread observation of such defects in pokrovskite in nature. Pokrovskite itself is most likely to form under CO2-rich/low water conditions, particularly those utilizing supercritical CO2 for carbon sequestration and is sufficiently thermodynamically stable to trap CO2 under geological conditions. Low temperature and high water concentration promotes the formation of proton substitution defects, which has implications for synthesis of any material where octahedral strain may be relieved by proton substitution defects.

  17. Green nanotechnology

    NASA Astrophysics Data System (ADS)

    Smith, Geoff B.

    2011-10-01

    Nanotechnology, in particular nanophotonics, is proving essential to achieving green outcomes of sustainability and renewable energy at the scales needed. Coatings, composites and polymeric structures used in windows, roof and wall coatings, energy storage, insulation and other components in energy efficient buildings will increasingly involve nanostructure, as will solar cells. Nanostructures have the potential to revolutionize thermoelectric power and may one day provide efficient refrigerant free cooling. Nanomaterials enable optimization of optical, opto-electrical and thermal responses to this urgent task. Optical harmonization of material responses to environmental energy flows involves (i) large changes in spectral response over limited wavelength bands (ii) tailoring to environmental dynamics. The latter includes engineering angle of incidence dependencies and switchable (or chromogenic) responses. Nanomaterials can be made at sufficient scale and low enough cost to be both economic and to have a high impact on a short time scale. Issues to be addressed include human safety and property changes induced during manufacture, handling and outdoor use. Unexpected bonuses have arisen in this work, for example the savings and environmental benefits of cool roofs extend beyond the more obvious benefit of reduced heat flows from the roof into the building.

  18. Green chromatography.

    PubMed

    Płotka, Justyna; Tobiszewski, Marek; Sulej, Anna Maria; Kupska, Magdalena; Górecki, Tadeusz; Namieśnik, Jacek

    2013-09-13

    Analysis of organic compounds in samples characterized by different composition of the matrix is very important in many areas. A vast majority of organic compound determinations are performed using gas or liquid chromatographic methods. It is thus very important that these methods have negligible environmental impact. Chromatographic techniques have the potential to be greener at all steps of the analysis, from sample collection and preparation to separation and final determination. The paper summarizes the approaches used to accomplish the goals of green chromatography. While complete elimination of sample preparation would be an ideal approach, it is not always practical. Solventless extraction techniques offer a very good alternative. Where solvents must be used, the focus should be on the minimization of their consumption. The approaches used to make chromatographic separations greener differ depending on the type of chromatography. In gas chromatography it is advisable to move away from using helium as the carrier gas because it is a non-renewable resource. GC separations using low thermal mass technology can be greener because of energy savings offered by this technology. In liquid chromatography the focus should be on the reduction of solvent consumption and replacement of toxic and environmentally hazardous solvents with more benign alternatives. Multidimensional separation techniques have the potential to make the analysis greener in both GC and LC. The environmental impact of the method is often determined by the location of the instrument with respect to the sample collection point.

  19. Green synthesis, spectroscopic investigation and photocatalytic activity of lead nanoparticles.

    PubMed

    Elango, Ganesh; Roopan, Selvaraj Mohana

    2015-03-15

    Most of researcher focused their research towards synthesize of nanoparticles by the method of applied chemical method which was one of the costliest method. We have focused cheapest and simplest method for the synthesizing of lead nanoparticles (Pb-NPs) using cocos nucifera L extract. The methanolic extract of cocos nucifera L was efficiently used as a reducing agent for synthesizing Pb-NPs. On treatment of lead acetate with cocos nucifera coir extracts, stable Pb-NPs were formed. The synthesized Pb-NPs were further confirmed by UV-visible spectroscopy, X-ray diffraction (XRD), Transmission electron microscope (TEM) and Energy Dispersive (EDAX) analysis. The secondary metabolites present in methanolic extract which can mainly act as a reducing and capping agents for the formation of Pb-NPs were identified by GC-MS. Anti-microbial activity for Pb-NPs against four pathogenic strain's such as Staphylococcus aureus, Escheria coli, Staphylococcus epidermis and Bacillus subtilis. Result states that Pb-NPs size was 47 nm and also shows good activity against S. aureus. Further we report on photocatalytic absorption of malachite green dye processed in short UV wavelength at 254 nm. UV spectral analysis showed peak absorbance at 613 nm with special reference to the excitation of surfaces plasmon vibration by Pb-NPs.

  20. Green synthesis, spectroscopic investigation and photocatalytic activity of lead nanoparticles

    NASA Astrophysics Data System (ADS)

    Elango, Ganesh; Roopan, Selvaraj Mohana

    2015-03-01

    Most of researcher focused their research towards synthesize of nanoparticles by the method of applied chemical method which was one of the costliest method. We have focused cheapest and simplest method for the synthesizing of lead nanoparticles (Pb-NPs) using cocos nucifera L extract. The methanolic extract of cocos nucifera L was efficiently used as a reducing agent for synthesizing Pb-NPs. On treatment of lead acetate with cocos nucifera coir extracts, stable Pb-NPs were formed. The synthesized Pb-NPs were further confirmed by UV-visible spectroscopy, X-ray diffraction (XRD), Transmission electron microscope (TEM) and Energy Dispersive (EDAX) analysis. The secondary metabolites present in methanolic extract which can mainly act as a reducing and capping agents for the formation of Pb-NPs were identified by GC-MS. Anti-microbial activity for Pb-NPs against four pathogenic strain's such as Staphylococcus aureus, Escheria coli, Staphylococcus epidermis and Bacillus subtilis. Result states that Pb-NPs size was 47 nm and also shows good activity against S. aureus. Further we report on photocatalytic absorption of malachite green dye processed in short UV wavelength at 254 nm. UV spectral analysis showed peak absorbance at 613 nm with special reference to the excitation of surfaces plasmon vibration by Pb-NPs.

  1. Fish Immunoglobulins

    PubMed Central

    Mashoof, Sara; Criscitiello, Michael F.

    2016-01-01

    The B cell receptor and secreted antibody are at the nexus of humoral adaptive immunity. In this review, we summarize what is known of the immunoglobulin genes of jawed cartilaginous and bony fishes. We focus on what has been learned from genomic or cDNA sequence data, but where appropriate draw upon protein, immunization, affinity and structural studies. Work from major aquatic model organisms and less studied comparative species are both included to define what is the rule for an immunoglobulin isotype or taxonomic group and what exemplifies an exception. PMID:27879632

  2. Fish Tales

    SciTech Connect

    McLerran, L.

    2010-07-06

    This talk is about fishing and the friendships that have resulted in its pursuit. It is also about theoretical physics, and the relationship of imagination and fantasy to the establishment of ideas about nature. Fishermen, like theoretical physicists, are well known for their inventive imaginations. Perhaps neither are as clever as sailors, who conceived of the mermaid. If one doubts the power of this fantasy, one should remember the ghosts of the many sailors who drowned pursuing these young nymphs. An extraordinary painting by J. Waterhouse is shown as Fig. 1. The enchantment of a mermaid must reflect an extraordinary excess of imagination on the part of the sailor, perhaps together with an impractical turn of mind. A consummated relationship with a mermaid is after all, by its very nature a fantasy incapable of realization. To a theoretical physicist, she is symbolic of many ideas we develop. There are many truths known to fisherman in which one might also find parallels to the goals of scientists: (1) A fish is the only animal that keeps growing after its death; (2) Nothing makes a fish bigger than almost being caught; (3) ''...of all the liars among mankind, the fisherman is the most trustworthy.'' (William Sherwood Fox, in Silken Lines and Silver Hooks); and (4) Men and fish are alike. They both get into trouble when they open their mouths. These quotes may be interpreted as reflecting skepticism regarding the honesty of fisherman, and probably do not reflect adequate admiration for a creative imagination. Is it fair to criticize a person for believing a falsehood that he or she sincerely believes to be true? The fisherman simultaneously invents the lie, and believes in it himself. The parallel with theoretical physics is perhaps only approximate, although we physicists may invent stories that we come to believe, on some rare occasions our ideas actually correspond to a more or less true descriptions of nature. These minor philosophical differences are not

  3. Great Lakes fish consumption and reproductive outcomes

    SciTech Connect

    Dar, E.

    1989-01-01

    This epidemiological investigation determined prenatal exposure to polychlorinated biphenyls (PCBs), through contaminated fish consumption, and ascertained reproductive outcomes. Green Bay, Wisconsin was chosen as the study site because it was known for its environmental contamination of PCBs. These chemicals are environmentally stable and persistent, and tend to bioaccumulate up the food chain, with highest levels found in predatory sport fish from Lake Michigan. The Green Bay area provided a population with potential PCB exposure from sport fish consumption. Accidental poisoning incidents showed detrimental reproductive effects of high dose PCB exposures. A Michigan study found significant effects on birth weight and gestational age when mothers consumed two sport fish meals per month. This study population was drawn from women during their first prenatal visit at two Green Bay clinics during a one year period. 1,112 participants completed a self-administered questionnaire. Maternal and cord blood samples were obtained for selected PCB serum analyses. Reproductive outcome measures were abstracted from hospital labor reports. Study results indicated that maternal consumption was correlated to maternal PCB serum levels. Regression techniques estimated significant exposure coefficients for subsets of two birth size parameters. Birth length was positively associated with PCB exposure in shorter mothers. Significant associations of PCB exposure and birth weight percentiles were estimated for two income groups in the urban residence/weight gain less than 34 pounds subset.

  4. Deep Fish.

    PubMed

    Ishaq, Omer; Sadanandan, Sajith Kecheril; Wählby, Carolina

    2017-01-01

    Zebrafish ( Danio rerio) is an important vertebrate model organism in biomedical research, especially suitable for morphological screening due to its transparent body during early development. Deep learning has emerged as a dominant paradigm for data analysis and found a number of applications in computer vision and image analysis. Here we demonstrate the potential of a deep learning approach for accurate high-throughput classification of whole-body zebrafish deformations in multifish microwell plates. Deep learning uses the raw image data as an input, without the need of expert knowledge for feature design or optimization of the segmentation parameters. We trained the deep learning classifier on as few as 84 images (before data augmentation) and achieved a classification accuracy of 92.8% on an unseen test data set that is comparable to the previous state of the art (95%) based on user-specified segmentation and deformation metrics. Ablation studies by digitally removing whole fish or parts of the fish from the images revealed that the classifier learned discriminative features from the image foreground, and we observed that the deformations of the head region, rather than the visually apparent bent tail, were more important for good classification performance.

  5. Green Power Partnership 100 Green Power Users

    EPA Pesticide Factsheets

    EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Partners on this list use green power to meet 100 of their U.S. organization-wide electricity use.

  6. Fertile green: green facilitates creative performance.

    PubMed

    Lichtenfeld, Stephanie; Elliot, Andrew J; Maier, Markus A; Pekrun, Reinhard

    2012-06-01

    The present research sought to extend the nascent literature on color and psychological functioning by examining whether perception of the color green facilitates creativity. In four experiments, we demonstrated that a brief glimpse of green prior to a creativity task enhances creative performance. This green effect was observed using both achromatic (white, gray) and chromatic (red, blue) contrast colors that were carefully matched on nonhue properties, and using both picture-based and word-based assessments of creativity. Participants were not aware of the purpose of the experiment, and null effects were obtained on participants' self-reported mood and positive activation. These findings indicate that green has implications beyond aesthetics and suggest the need for sustained empirical work on the functional meaning of green.

  7. Urban Greening Bay Area

    EPA Pesticide Factsheets

    Information about the San Francisco Bay Water Quality Project (SFBWQP) Urban Greening Bay Area, a large-scale effort to re-envision urban landscapes to include green infrastructure (GI) making communities more livable and reducing stormwater runoff.

  8. Green Infrastructure Modeling Toolkit

    EPA Pesticide Factsheets

    EPA's Green Infrastructure Modeling Toolkit is a toolkit of 5 EPA green infrastructure models and tools, along with communication materials, that can be used as a teaching tool and a quick reference resource when making GI implementation decisions.

  9. What Is Green Power?

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership defines Green power is a subset of renewable energy and represents those renewable energy resources and technologies that provide the highest environmental benefit.

  10. Green Infrastructure Modeling Tools

    EPA Pesticide Factsheets

    Modeling tools support planning and design decisions on a range of scales from setting a green infrastructure target for an entire watershed to designing a green infrastructure practice for a particular site.

  11. Green Power Markets

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership defines Green power is a subset of renewable energy and represents those renewable energy resources and technologies that provide the highest environmental benefit.

  12. Green Power Communities

    EPA Pesticide Factsheets

    GPCs are towns, villages, cities, counties, or tribal governments in which the local government, businesses, and residents collectively use green power in amounts that meet or exceed EPA's Green Power Community purchase requirements.

  13. Green Power Community Benefits

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Learn more about becoming a Green Power Community, including recognition opportunities.

  14. Green Infrastructure Modeling Toolkit

    EPA Science Inventory

    Green infrastructure, such as rain gardens, green roofs, porous pavement, cisterns, and constructed wetlands, is becoming an increasingly attractive way to recharge aquifers and reduce the amount of stormwater runoff that flows into wastewater treatment plants or into waterbodies...

  15. Green Flight Challenge

    NASA Video Gallery

    The CAFE Green Flight Challenge sponsored by Google will be held at the CAFE Foundation Flight Test Center at Charles M. Schulz Sonoma County Airport in Santa Rosa, Calif. The Green Flight Challeng...

  16. Tribal Green Building Toolkit

    EPA Pesticide Factsheets

    This Tribal Green Building Toolkit (Toolkit) is designed to help tribal officials, community members, planners, developers, and architects develop and adopt building codes to support green building practices. Anyone can use this toolkit!

  17. Green Power Partner List

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. There are thousands of Green Power Partners, all listed on this page.

  18. Fishing amplifies forage fish population collapses.

    PubMed

    Essington, Timothy E; Moriarty, Pamela E; Froehlich, Halley E; Hodgson, Emma E; Koehn, Laura E; Oken, Kiva L; Siple, Margaret C; Stawitz, Christine C

    2015-05-26

    Forage fish support the largest fisheries in the world but also play key roles in marine food webs by transferring energy from plankton to upper trophic-level predators, such as large fish, seabirds, and marine mammals. Fishing can, thereby, have far reaching consequences on marine food webs unless safeguards are in place to avoid depleting forage fish to dangerously low levels, where dependent predators are most vulnerable. However, disentangling the contributions of fishing vs. natural processes on population dynamics has been difficult because of the sensitivity of these stocks to environmental conditions. Here, we overcome this difficulty by collating population time series for forage fish populations that account for nearly two-thirds of global catch of forage fish to identify the fingerprint of fisheries on their population dynamics. Forage fish population collapses shared a set of common and unique characteristics: high fishing pressure for several years before collapse, a sharp drop in natural population productivity, and a lagged response to reduce fishing pressure. Lagged response to natural productivity declines can sharply amplify the magnitude of naturally occurring population fluctuations. Finally, we show that the magnitude and frequency of collapses are greater than expected from natural productivity characteristics and therefore, likely attributed to fishing. The durations of collapses, however, were not different from those expected based on natural productivity shifts. A risk-based management scheme that reduces fishing when populations become scarce would protect forage fish and their predators from collapse with little effect on long-term average catches.

  19. Indicators: Fish Assemblage

    EPA Pesticide Factsheets

    Fish assemblage refers to the variety and abundance of fish species in a given waterbody. Fish are sensitive indicators of physical and chemical habitat degradation, environmental contamination, migration barriers, and overall ecosystem productivity.

  20. Fish tapeworm infection

    MedlinePlus

    Fish tapeworm infection is an intestinal infection with the tapeworm parasite found in fish. ... The fish tapeworm ( Diphyllobothrium latum ) is the largest parasite that infects humans. Humans become infected when they eat raw or undercooked ...

  1. Renal changes in selenium-exposed fish

    SciTech Connect

    Sorensen, E.M.; Harlan, C.W.; Bell, J.S.

    1982-06-01

    A group of green sunfish was collected from a selenium-rich lake and compared with a similar group collected from a control lake upstream in the same drainage system in east Texas. Since the level of selenium in kidneys of these fish was relatively high (averaging 11 ppm on a fresh weight basis), histopathological and ultrastructural data were collected. Kidneys from fish from the selenium-rich lake showed proliferative glomerulonephritis and hematuria as well as vacuolation and necrosis of cells of the convoluted tubules.

  2. Green Streets Help Baltimore, Others

    EPA Pesticide Factsheets

    Fifteen Green Streets, Green Towns, Green Jobs (G3) grants for will support projects in three states, including the conversion of hard surfaces to green space at Sarah’s Hope, a homeless shelter in a troubled Baltimore neighborhood.

  3. Show Me the Green

    ERIC Educational Resources Information Center

    Norbury, Keith

    2013-01-01

    Gone are the days when green campus initiatives were a balm to the soul and a drain on the wallet. Today's environmental initiatives are all about saving lots of green--in every sense of the word. The environmental benefits of green campus projects--whether wind turbines or better insulation--are pretty clear. Unfortunately, in today's…

  4. EPA's Green Roof Research

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provices insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA re...

  5. The Green Man

    ERIC Educational Resources Information Center

    Watson-Newlin, Karen

    2010-01-01

    The Jolly Green Giant. Robin Hood. The Bamberg Cathedral. Tales of King Arthur. Ecology. What do they have in common? What legends and ancient myths are shrouded in the tales of the Green Man? Most often perceived as an ancient Celtic symbol as the god of spring and summer, the Green Man disappears and returns year after year, century after…

  6. In the Green

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2011-01-01

    Education officials used to debate whether they could afford to pursue green design and construction. Now the green movement has gained a foothold not just in education, but in society at large, and the prevailing attitude seems to have shifted. Can schools afford "not" to go green? As budgets are slashed repeatedly, education administrators must…

  7. Green Power Communities Brochure

    EPA Pesticide Factsheets

    The Green Power Communities Brochure provides basic information about GPP's Green Power Communities (GPCs). The four-page brochure includes information about how to become a GPC, the benefits of procuring green power, and examples of how current GPCs are u

  8. Public Libraries Going Green

    ERIC Educational Resources Information Center

    Miller, Kathryn

    2010-01-01

    Going green is now a national issue, and patrons expect their library to respond in the same way many corporations have. Libraries are going green with logos on their Web sites, programs for the public, and a host of other initiatives. This is the first book to focus strictly on the library's role in going green, helping you with: (1) Collection…

  9. What Is Green?

    ERIC Educational Resources Information Center

    Pokrandt, Rachel

    2010-01-01

    Green is a question with varying answers and sometimes no answer at all. It is a question of location, resources, people, environment, and money. As green really has no end point, a teacher's goal should be to teach students to question and consider green. In this article, the author provides several useful metrics to help technology teachers…

  10. Fish mycobacteriosis (Tuberculosis)

    USGS Publications Warehouse

    Parisot, T.J.; Wood, J.W.

    1959-01-01

    The etiologic agent for the bacterial disease, "fish tuberculosis" (more correctly "mycobacteriosis"), was first observed in carp in 189& from a pond in France. Subsequently similar agents have been isolated from or observed in fish in fresh water, salt water, and brackish water, in fish in aquaria, hatcheries, and natural habitat~ (wild populations of fish). The disease has been recognized as an important infection among hatchery reared salmonid fishes on the West Coast of the United States, and in aquarium fishes such as the neon tetra, the Siamese fighting fish, and in salt water fish held in zoological displays.

  11. Indocyanine green video angiography

    NASA Astrophysics Data System (ADS)

    Frambach, Donald A.

    1994-06-01

    Over the last two years, ophthalmologists have begun to use indocyanine green angiography as a supplement to fluorescein angiography. Unlike fluorescein, indocyanine green absorbs near infrared and emits slightly longer infrared light. Therefore, indocyanine green angiography images structures deeper in the retina and through blood, pigment, and turbid serous fluid that accumulates in a number of diseases. In addition, indocyanine green shows very different properties of dye leakage than does fluorescein and this can be used to identify certain abnormal blood vessels that grow beneath the retinas of patients with macular degeneration. Finally, indocyanine green fluoresces only 4% as efficiently as fluorescein which has presented a major technical problem until highly amplified video systems have become available to ophthalmologists. We have used a scanning laser ophthalmoscope to perform video indocyanine green angiography at the Doheny Eye Institute since November, 1991. In this paper, I will present several clinical cases that demonstrate the clinical usefulness of indocyanine green angiography.

  12. Evaluation of medicated feeds with antiparasitical and immune-enhanced Chinese herbal medicines against Ichthyophthirius multifiliis in grass carp (Ctenopharyngodon idellus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ichthyophthirius multifiliis (Ich) is a widespread ciliated ectoparasite and results in severe economic loss in the aquaculture industry. Since malachite green was banned for using in food fish due to its carcinogenic and teratogenic effects on human, the search of alternative drug to treat I. multi...

  13. New insights into the red and green pigments in the illuminated foral charter of Setubal (1515) by combined use of μ-Raman and X-ray fluorescence spectrometry

    NASA Astrophysics Data System (ADS)

    Guerra, M.; Carvalho, M. L.; Le Gac, A.; Manso, M.; Mortari, C.; Longelin, S.; Pessanha, S.

    2016-03-01

    The richly decorated foral charter attributed by D. Manuel I of Portugal, in 1515, to the village of Setubal, was studied using Energy Dispersive X-ray Fluorescence spectrometry and Raman micro-spectroscopy. An in situ characterization of the pigments used in the production of this masterpiece showed a very different pigment palette choice when compared to other similar Manueline charters. The red and green pigments are particularly puzzling, as the widely used mercury- and copper-based pigments, vermillion and malachite, respectively, were not found in the illuminated frontispiece. Instead, the cheaper lead-based pigment minium was used in the King's flag, while a mixture of copper sulfates was found for the green color, identified by means of micro-Raman spectroscopy. This result led to a new look at the conception that only one Royal workshop existed for the elaboration of Manueline foral charters.

  14. Selective Preservation of Fossil Ghost Fish

    NASA Astrophysics Data System (ADS)

    Meacham, Amanda

    2016-04-01

    A unique type of fossil fish preservation has been discovered in the Angelo Member (Fossil Lake) of the Green River Formation. The Angelo Member is a predominately evaporative deposit dominated by dolomite, but contains facies of fossiliferous laminated calcimicrite. Fossil fish occurring in two beds conspicuously lack bones. Fish in the lower bed are only preserved as organic material, including skin, pigments, and eyes. Fish in the upper bed have three-dimensional etching where bones once existed but also contain skin, pigments, and eyes. The top third of the upper bed often contains calcite crystals that are pseudomorphs after trona and possibly halite. Preliminary mineralogical analysis and mapping of evaporate facies suggests that this unique preservation may be related to lake geochemical conditions, such as high pH and alkalinity. To our knowledge, this is the first time this type of preservation has been observed and studied. Fossils and sediments within these beds are being studied both vertically and laterally through the one-meter thick sequence containing the fossil fish using XRD, isotopic, SEM, thin section, and total organic carbon analysis. Nine quarries, 0.5-1 meter square, were excavated for both fossils and rock samples along with 17 additional rock sample locations across an approximately 25-kilometer square region. This investigation has the capability of reconstructing the paleoenvironment and lake chemistry of Fossil Lake during the deposition of the "ghost-fish" beds and solving the mystery of the "missing bones" and the unusual process of preservation.

  15. Identification of green pigments from fragments of Roman mural paintings of three Roman sites from north of Germania Superior

    NASA Astrophysics Data System (ADS)

    Debastiani, Rafaela; Simon, Rolf; Goettlicher, Joerg; Heissler, Stefan; Steininger, Ralph; Batchelor, David; Fiederle, Michael; Baumbach, Tilo

    2016-10-01

    Roman mural green pigment painting fragments from three Roman sites in the north of the Roman province Germania Superior: Koblenz Stadtwald Remstecken (KOSR), Weißenthurm " Am guten Mann" (WEIS) and Mendig Lungenkärchen (MELU), dating from second and third centuries AD were analyzed. The experiments were performed nondestructively using synchrotron-based scanning macro-X-ray fluorescence (SR-MA-XRF), synchrotron-based scanning micro-X-ray fluorescence (SR-μ-XRF), synchrotron-based X-ray diffraction (SR-XRD) and Raman spectroscopy. Correlation between SR-MA-XRF, SR-μ-XRF elemental map distributions and optical images of scanned areas was mainly found for the elements Ca, Fe and K. With XRF, Fe and K were identified correlated with green pigment, but in samples from two sites, Mendig Lungenkärchen and Weißenthurm " Am guten Mann", also Cu was detected in minor concentration. The results of SR-XRD and Raman spectroscopy were limited to one sample from Weißenthurm " Am guten Mann". In this sample, green earth and calcium carbonate were identified by SR-XRD and, additionally, malachite by Raman spectroscopy.

  16. Aegle marmelos Mediated Green Synthesis of Different Nanostructured Metal Hexacyanoferrates: Activity against Photodegradation of Harmful Organic Dyes

    PubMed Central

    Jassal, Vidhisha; Kaith, B. S.

    2016-01-01

    Prussian blue analogue potassium metal hexacyanoferrate (KMHCF) nanoparticles Fe4[Fe(CN)6]3 (FeHCF), K2Cu3[Fe(CN)6]2 (KCuHCF), K2Ni[Fe(CN)6]·3H2O (KNiHCF), and K2Co[Fe(CN)6] (KCoHCF) have been synthesized using plant based biosurfactant Aegle marmelos (Bael) and water as a green solvent. It must be emphasized here that no harmful reagent or solvent was used throughout the study. Plant extracts are easily biodegradable and therefore do not cause any harm to the environment. Hence, the proposed method of synthesis of various KMHCF nanoparticles followed a green path. The synthesized nanoparticles were characterized by powder X-ray diffraction (PXRD), Field-Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FT-IR). MHCF nanoparticles were used for the photocatalytic degradation of toxic dyes like Malachite Green (MG), Eriochrome Black T (EBT), Methyl Orange (MO), and Methylene Blue (MB). Under optimized reaction conditions, maximum photocatalytic degradation was achieved in case of KCuHCF nanoparticles mediated degradation process (MG: 96.06%, EBT: 83.03%, MB: 94.72%, and MO: 63.71%) followed by KNiHCF (MG: 95%, EBT: 80.32%, MB: 91.35%, and MO: 59.42%), KCoHCF (MG: 91.45%, EBT: 78.84%, MB: 89.28%, and MO: 58.20%). PMID:27034896

  17. Greening America's Communities

    EPA Pesticide Factsheets

    Technical assistance program to help cities and towns develop an implementable vision of distinctive, environmentally friendly neighborhoods using green infrastructure and other sustainable design strategies.

  18. Experimental Observations of the Patterns of Fungi-Mineral Surfaces Interactions with Muscovite, Biotite, Bauxite, Chromite, Hematite, Galena, Malachite, Manganite and Carbonate Substrates.

    NASA Astrophysics Data System (ADS)

    Claeys, P.

    2006-12-01

    In an in vitro experimental work, mineral substrates of muscovite, biotite, bauxite, chromite, hematite, galena, malachite, manganite and carbonate were exposed to free fungal growth and interaction in Petri dishes under open conditions. All of the experimental minerals were examined by XRD for identity and purity. The 12-week experiment resulted in significant alteration of the mineral substrates. SEM, EDX, and XRD analysis showed secondary mineral biomineralization represented by different crystal morphologies of Ca- and Mg- oxalates (weddelite: CaC2O4·2H2O, whewellite CaC2O4·H2O and glushinskite: MgC2O4·2H2O), struvite: (NH4) MgPO4·6H2O, gypsum CaSO4.2H2O, and possible dolomite. Metals bioleached from the substrates included: Fe, Pb, S, Cu, Al as single crystals or aggregates, amorphous layers, amorphous aggregates, and linear forms influenced by the fungal filaments. Bauxite and manganite showed the strongest cases of bioleaching where Fe and Al were fungally extracted and deposited as separate mineral species from the Al-Fe oxides mixture, while Ca and S were extracted from the manganite substrate and deposited as gypsum. The bioleached metals were either deposited on the mineral substrates, attached to fungal filaments, embedded in the fungal mycelium or in the extracellular polysaccharide substance (EPS) layer. The EDX microanalysis of the fungal hyphae frequently revealed metal content adsorbed on the hyphae sheath surface. During the short period of the experiment, fungal interaction with the mineral surfaces produced significant biomechanical and biochemical bioweathering features: strong pitting of the mineral surfaces, exfoliation, tunnelling, dissolution, honeycomb-alveolar structures, perforations, fragmentation, and cementation. One important aspect of these interactions is the strong affinity of fungal hyphae to mineral surfaces. The fungi engulfed whole blocks of minerals in the hyphal network, irrespective of mineral surface topography with

  19. Fish Oil Supplementation and Fatty Acid Synthase Expression in the Prostate: A Randomized Controlled Trial

    DTIC Science & Technology

    2009-03-01

    randomized to receive three months of either fish oil capsules (treatment 1) or olive oil (placebo) capsules (treatment 2). Potential...sensitivity to fish oil, olive oil or green tea • Subject reported history of hemophilia, van Willebrands disease or other bleeding disorder, except

  20. Green Cleaning Label Power

    ERIC Educational Resources Information Center

    Balek, Bill

    2012-01-01

    Green cleaning plays a significant and supportive role in helping education institutions meet their sustainability goals. However, identifying cleaning products, supplies and equipment that truly are environmentally preferable can be daunting. The marketplace is inundated with products and services purporting to be "green" or environmentally…

  1. Greening the Future

    ERIC Educational Resources Information Center

    Williamson, Norma Velia

    2011-01-01

    Because educators vicariously touch the future through their students, the author believes that they sometimes have the uncanny ability to see the future. One common future forecast is the phenomenal growth of green jobs in the emerging green economy, leading to the creation of the "Reach of the Sun" Solar Energy Academy at La Mirada…

  2. Green Building Research Laboratory

    SciTech Connect

    Sailor, David Jean

    2013-12-29

    This project provided support to the Green Building Research Laboratory at Portland State University (PSU) so it could work with researchers and industry to solve technical problems for the benefit of the green building industry. It also helped to facilitate the development of PSU’s undergraduate and graduate-level training in building science across the curriculum.

  3. Greening the Curriculum

    ERIC Educational Resources Information Center

    Kaye, Cathryn Berger

    2012-01-01

    The green concept has tremendous value in schools, especially when it reflects the central purpose and mission of schools: educating young people to participate and civically engage in society. School communities that keep greening the school on the periphery of their awareness will reap advantages, but those that align this idea with the…

  4. Green Chemistry and Education.

    ERIC Educational Resources Information Center

    Hjeresen, Dennis L.; Schutt, David L.; Boese, Janet M.

    2000-01-01

    Many students today are profoundly interested in the sustainability of their world. Introduces Green Chemistry and its principles with teaching materials. Green Chemistry is the use of chemistry for pollution prevention and the design of chemical products and processes that are environmentally benign. (ASK)

  5. Lighting: Green Light.

    ERIC Educational Resources Information Center

    Maniccia, Dorine

    2003-01-01

    Explains that by using sustainable (green) building practices, schools and universities can make their lighting systems more efficient, noting that embracing green design principles can help schools attract students. Discusses lighting-control technologies (occupancy sensing technology, daylighting technology, and scheduling based technologies),…

  6. Green Buildings and Health.

    PubMed

    Allen, Joseph G; MacNaughton, Piers; Laurent, Jose Guillermo Cedeno; Flanigan, Skye S; Eitland, Erika Sita; Spengler, John D

    2015-09-01

    Green building design is becoming broadly adopted, with one green building standard reporting over 3.5 billion square feet certified to date. By definition, green buildings focus on minimizing impacts to the environment through reductions in energy usage, water usage, and minimizing environmental disturbances from the building site. Also by definition, but perhaps less widely recognized, green buildings aim to improve human health through design of healthy indoor environments. The benefits related to reduced energy and water consumption are well-documented, but the potential human health benefits of green buildings are only recently being investigated. The objective of our review was to examine the state of evidence on green building design as it specifically relates to indoor environmental quality and human health. Overall, the initial scientific evidence indicates better indoor environmental quality in green buildings versus non-green buildings, with direct benefits to human health for occupants of those buildings. A limitation of much of the research to date is the reliance on indirect, lagging and subjective measures of health. To address this, we propose a framework for identifying direct, objective and leading "Health Performance Indicators" for use in future studies of buildings and health.

  7. Sowing Green Seeds

    ERIC Educational Resources Information Center

    Yingjun, Chen; Jianzhuang, Rong

    2004-01-01

    This article deals with the development of environmental education Hunan Yueyang Middle School Number One. Famous for its beautiful environment and lush green trees, the school has won titles such as "park" unit, "garden" school, "green school" and "National Advanced Unit for Environmental Education." In…

  8. Custodial Operations: Green & Sustainable

    ERIC Educational Resources Information Center

    Campbell, J. Kirk

    2008-01-01

    Custodial Operations can have a significant impact on institutional green and sustainable goals if given the proper support and challenge. This article describes the green and sustainable custodial operations in place at Carleton College in Northfield, Minnesota. The article reviews the college's sustainable efforts on biodegradables, packaging,…

  9. 10 Paths to Green

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2008-01-01

    Some institutions may feel comfortable with a few baby steps into the green world, while others may be ready to commit totally to environmental consciousness. Here, the author discusses 10 areas in which educators and administrators can beef up their green portfolio. These areas are in: alternative fuel, bikes/walking, water, education tools,…

  10. A Green Clean

    ERIC Educational Resources Information Center

    Kravitz, Robert

    2006-01-01

    In the professional cleaning industry, green cleaning has been much discussed in the past few years. Usually, the information pertains to the many reasons why a green cleaning program should be started, the steps involved to get the program off the ground, and the potential benefits. However, although many facility managers and school…

  11. Green tea in dermatology.

    PubMed

    Pazyar, Nader; Feily, Amir; Kazerouni, Afshin

    2012-01-01

    The purpose of this brief review is to summarize all in vitro, in vivo, and controlled clinical trials on green tea preparations and their uses in dermatology. An extensive literature search was carried out to identify in vivo and in vitro studies as well as clinical trials. Twenty studies were assessed and the results suggest that oral administration of green tea can be effective in the scavenging of free radicals, cancer prevention, hair loss, and skin aging plus protection against the adverse effects associated with psoralen-UV-A therapy. Topical application of green tea extract should be potentially effective for atopic dermatitis, acne vulgaris, rosacea, androgenetic alopecia, hirsutism, keloids, genital warts, cutaneous leishmaniasis, and candidiosis. There are promising results with the use of green tea for several dermatologic conditions; however, the efficacy of oral and topical green tea has not always been confirmed.

  12. Building the green way.

    PubMed

    Lockwood, Charles

    2006-06-01

    Just five or six years ago, the term "green building" evoked visions of barefoot, tie-dyed, granola-munching denizens. There's been a large shift in perception. Of course, green buildings are still known for conserving natural resources by, for example, minimizing on-site grading, using alternative materials, and recycling construction waste. But people now see the financial advantages as well. Well-designed green buildings yield lower utility costs, greater employee productivity, less absenteeism, and stronger attraction and retention of workers than standard buildings do. Green materials, mechanical systems, and furnishings have become more widely available and considerably less expensive than they used to be-often cheaper than their standard counterparts. So building green is no longer a pricey experiment; just about any company can do it on a standard budget by following the ten rules outlined by the author. Reliable building-rating systems like the U.S. Green Building Council's rigorous Leadership in Energy and Environmental Design (LEED) program have done much to underscore the benefits of green construction. LEED evaluates buildings and awards points in several areas, such as water efficiency and indoor environmental quality. Other rating programs include the UK's BREEAM (Building Research Establishment's Environmental Assessment Method) and Australia's Green Star. Green construction is not simply getting more respect; it is rapidly becoming a necessity as corporations push it fully into the mainstream over the next five to ten years. In fact, the author says, the owners of standard buildings face massive obsolescence. To avoid this problem, they should carry out green renovations. Corporations no longer have an excuse for eschewing environmental and economic sustainability. They have at their disposal tools proven to lower overhead costs, improve productivity, and strengthen the bottom line.

  13. Scorpion fish sting

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002849.htm Scorpion fish sting To use the sharing features on this page, please enable JavaScript. Scorpion fish are members of the family Scorpaenidae, which ...

  14. Going Green: Greening Your Marketing Efforts

    ERIC Educational Resources Information Center

    Germain, Carol Anne

    2009-01-01

    There is no doubt that the "Going Green" movement is in full swing. With global warming and other ecological concerns, people are paying closer attention to environmental issues and striving to live in a more sustainable world. For libraries, this is a perfect opportunity to be active in a campus-wide program and simultaneously promote library…

  15. Collection Development "Green Business": The Green Capitalist

    ERIC Educational Resources Information Center

    Eagan, Robert

    2009-01-01

    The "greening" of corporate behemoths like Wal-Mart, DuPont, and Toyota has received much media attention in recent years. But consider small businesses: according to the U.S. Small Business Administration, of the estimated 27 million firms in the United States, 99.7 percent have fewer than 500 employees, 97.5 percent have fewer than 20, and more…

  16. Clarkesville Green Infrastructure Implementation Strategy

    EPA Pesticide Factsheets

    The report outlines the 2012 technical assistance for Clarkesville, GA to develop a Green Infrastructure Implementation Strategy, which provides the basic building blocks for a green infrastructure plan:

  17. 49 CFR 173.218 - Fish meal or fish scrap.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Fish meal or fish scrap. 173.218 Section 173.218... Fish meal or fish scrap. (a) Except as provided in Column (7) of the HMT in § 172.101 of this subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized...

  18. Poisoning - fish and shellfish

    MedlinePlus

    ... contaminated waters. Scombroid poisoning usually occurs from large, dark meat fish such as tuna, mackerel, mahi mahi, and albacore. Because this poison develops after a fish is caught and dies, it does not matter where the fish is caught. The main factor ...

  19. Fishing for Environmental Education.

    ERIC Educational Resources Information Center

    Matthews, Bruce

    1994-01-01

    Teaching students to fish not only develops a lifetime leisure skill but also leads to an understanding of aquatic ecosystems and encourages student connection with the natural environment. Addresses educational benefits of incorporating fishing into environmental education and describes how two fishing programs successfully met objectives of…

  20. Green Light Pulse Oximeter

    DOEpatents

    Scharf, John Edward

    1998-11-03

    A reflectance pulse oximeter that determines oxygen saturation of hemoglobin using two sources of electromagnetic radiation in the green optical region, which provides the maximum reflectance pulsation spectrum. The use of green light allows placement of an oximetry probe at central body sites (e.g., wrist, thigh, abdomen, forehead, scalp, and back). Preferably, the two green light sources alternately emit light at 560 nm and 577 nm, respectively, which gives the biggest difference in hemoglobin extinction coefficients between deoxyhemoglobin, RHb, and oxyhemoglobin, HbO.sub.2.

  1. Fish allergy: in review.

    PubMed

    Sharp, Michael F; Lopata, Andreas L

    2014-06-01

    Globally, the rising consumption of fish and its derivatives, due to its nutritional value and divergence of international cuisines, has led to an increase in reports of adverse reactions to fish. Reactions to fish are not only mediated by the immune system causing allergies, but are often caused by various toxins and parasites including ciguatera and Anisakis. Allergic reactions to fish can be serious and life threatening and children usually do not outgrow this type of food allergy. The route of exposure is not only restricted to ingestion but include manual handling and inhalation of cooking vapors in the domestic and occupational environment. Prevalence rates of self-reported fish allergy range from 0.2 to 2.29 % in the general population, but can reach up to 8 % among fish processing workers. Fish allergy seems to vary with geographical eating habits, type of fish processing, and fish species exposure. The major fish allergen characterized is parvalbumin in addition to several less well-known allergens. This contemporary review discusses interesting and new findings in the area of fish allergy including demographics, novel allergens identified, immunological mechanisms of sensitization, and innovative approaches in diagnosing and managing this life-long disease.

  2. Fish under exercise.

    PubMed

    Palstra, Arjan P; Planas, Josep V

    2011-06-01

    Improved knowledge on the swimming physiology of fish and its application to fisheries science and aquaculture (i.e., farming a fitter fish) is currently needed in the face of global environmental changes, high fishing pressures, increased aquaculture production as well as increased concern on fish well-being. Here, we review existing data on teleost fish that indicate that sustained exercise at optimal speeds enhances muscle growth and has consequences for flesh quality. Potential added benefits of sustained exercise may be delay of ovarian development and stimulation of immune status. Exercise could represent a natural, noninvasive, and economical approach to improve growth, flesh quality as well as welfare of aquacultured fish: a FitFish for a healthy consumer. All these issues are important for setting directions for policy decisions and future studies in this area. For this purpose, the FitFish workshop on the Swimming Physiology of Fish ( http://www.ub.edu/fitfish2010 ) was organized to bring together a multidisciplinary group of scientists using exercise models, industrial partners, and policy makers. Sixteen international experts from Europe, North America, and Japan were invited to present their work and view on migration of fishes in their natural environment, beneficial effects of exercise, and applications for sustainable aquaculture. Eighty-eight participants from 19 different countries contributed through a poster session and round table discussion. Eight papers from invited speakers at the workshop have been contributed to this special issue on The Swimming Physiology of Fish.

  3. Superfund Green Remediation

    EPA Pesticide Factsheets

    Green remediation is the practice of considering all environmental effects of site cleanup and incorporating options – like the use of renewable energy resources – to maximize the environmental benefits of cleanups.

  4. Green Ampt approximations

    NASA Astrophysics Data System (ADS)

    Barry, D. A.; Parlange, J.-Y.; Li, L.; Jeng, D.-S.; Crapper, M.

    2005-10-01

    The solution to the Green and Ampt infiltration equation is expressible in terms of the Lambert W-1 function. Approximations for Green and Ampt infiltration are thus derivable from approximations for the W-1 function and vice versa. An infinite family of asymptotic expansions to W-1 is presented. Although these expansions do not converge near the branch point of the W function (corresponds to Green-Ampt infiltration with immediate ponding), a method is presented for approximating W-1 that is exact at the branch point and asymptotically, with interpolation between these limits. Some existing and several new simple and compact yet robust approximations applicable to Green-Ampt infiltration and flux are presented, the most accurate of which has a maximum relative error of 5 × 10 -5%. This error is orders of magnitude lower than any existing analytical approximations.

  5. Green Power Procurement Considerations

    EPA Pesticide Factsheets

    Green power products are available from a variety of different vendors, including utilities, renewable energy certificate (REC) marketers, on-site system integrators, and non-profit organizations. This page lists considerations to evaluate during selection

  6. Green Building Standards

    EPA Pesticide Factsheets

    Many organizations have developed model codes or rating systems that communities may use to develop green building programs or revise building ordinances. Some of the major options are listed on this page.

  7. Green Supercomputing at Argonne

    SciTech Connect

    Pete Beckman

    2009-11-18

    Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF) talks about Argonne National Laboratory's green supercomputing—everything from designing algorithms to use fewer kilowatts per operation to using cold Chicago winter air to cool the machine more efficiently.

  8. Green Power Partnership Scope

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary partnership program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Organizations can elect to join organization-wide or at the facility level.

  9. Green Power Partnership Requirements

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary partnership program designed to reduce the environmental impact of electricity generation by promoting renewable energy. To join, organizations must meet EPA's program requirements.

  10. Cholesterol Oxidation in Fish and Fish Products.

    PubMed

    Dantas, Natalie Marinho; Sampaio, Geni Rodrigues; Ferreira, Fernanda Silva; Labre, Tatiana da Silva; Torres, Elizabeth Aparecida Ferraz da Silva; Saldanha, Tatiana

    2015-12-01

    Fish and fish products are important from a nutritional point of view due to the presence of high biological value proteins and the high content of polyunsaturated fatty acids, especially those of the n-3 series, and above all eicosapentaenoic acid and docosahexaenoic acid. However, these important food products also contain significant amounts of cholesterol. Although cholesterol participates in essential functions in the human body, it is unstable, especially in the presence of light, oxygen, radiation, and high temperatures that can cause the formation of cholesterol oxidation products or cholesterol oxides, which are prejudicial to human health. Fish processing involves high and low temperatures, as well as other methods for microbiological control, which increases shelf life and consequently added value; however, such processes favor the formation of cholesterol oxidation products. This review brings together data on the formation of cholesterol oxides during the preparation and processing of fish into food products which are recognized and recommended for their nutritional properties.

  11. Can greening of aquaculture sequester blue carbon?

    PubMed

    Ahmed, Nesar; Bunting, Stuart W; Glaser, Marion; Flaherty, Mark S; Diana, James S

    2016-11-15

    Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

  12. Why fishes have a fish shape

    NASA Astrophysics Data System (ADS)

    Eloy, Christophe; Schouveiler, Lionel

    2010-11-01

    The relation between form and function for elongated swimmers is revisited by solving a multi-objective optimization problem. We consider elongated fishes of varying elliptic cross-section whose motion is prescribed by a time-periodic curvature. The two semi-axes of the cross-section, the curvature amplitude and phase are assumed to vary continuously along the fish length. Hydrodynamic forces acting on such fishes are modeled in the elongated-body limit by considering both reactive and resistive forces. Applying Newton's second law, the heave and pitch amplitude and phase, as well as the swimming velocity can be found. The total power needed can also be calculated yielding the swimming efficiency. The multi-objective optimization consists in finding the fish shape and associated motion which corresponds to maximum efficiency, maximum velocity or any trade-off between the two. This optimization problem is solved using a genetic algorithm whose principle is to start with an initial random population and to evolve it by mutation and selection. We find that the most efficient shape resembles existing fishes and arguments are given to explain the relation between this particular fish form and performance.

  13. Fish elevator and method of elevating fish

    DOEpatents

    Truebe, Jonathan; Drooker, Michael S.

    1984-01-01

    A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

  14. Beta vulgaris aided green synthesis of ZnO nanoparticles and their luminescence, photocatalytic and antioxidant properties

    NASA Astrophysics Data System (ADS)

    Pavan Kumar, M. A.; Suresh, D.; Nagabhushana, H.; Sharma, S. C.

    2015-06-01

    Multifunctional zinc oxide nanoparticles (ZnO Nps) were synthesized by solution combustion synthesis using beetroots ( Beta vulgaris). The structure and morphology of the product were studied by powder X-ray diffraction, UV-visible spectroscopy and scanning electron microscopy. XRD studies indicate the formation of Nps with hexagonal wurtzite structure having crystallite sizes in the range of ˜ 52-76 nm. The UV-visible spectrum of Nps shows maximum absorption at 373 nm. The SEM analysis indicates the formation of porous, sponge-like agglomerated structures. Very interesting room temperature luminescence phenomena were observed with violet, green and red emissions upon exciting the ZnO Nps at 378 nm. This phenomenon could be due to oxygen vacancy and ZnO interstitial defects. ZnO Nps effectively degrade malachite green (MG) and methylene blue (MB) dyes in the presence of UV light. Nps show good antioxidant activity by scavenging 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals. The study successfully demonstrates simple, economical and ecofriendly methods of synthesis of multifunctional ZnO Nps. Nps may be used as good color tunable phosphor materials. The method demonstrated in this study is suggested as an effective replacement for the hazardous chemical methods of production of zinc oxide nanoparticles.

  15. Parádsasvárite, a new member of the malachite-rosasite group from Parádsasvár, Mátra Mountains, Hungary

    NASA Astrophysics Data System (ADS)

    Fehér, Béla; Szakáll, Sándor; Zajzon, Norbert; Mihály, Judith

    2015-08-01

    Parádsasvárite (IMA No. 2012-077) was found in the Nagy-Lápafő area, Parádsasvár, Mátra Mountains, Hungary. It forms pale beige, globular aggregates up to 0.2 mm in diameter on calcite. Associated secondary minerals are smithsonite, hemimorphite, hydrozincite, aurichalcite and rosasite. The mineral was formed as an alteration product of sphalerite and chalcopyrite in a carbonate-rich environment. Parádsasvárite is translucent with a weakly vitreous, dull or silky lustre and white streak. Its Mohs hardness is about 2-3, cleavage and parting were not observed. It is brittle; the fracture is finely fibrous. Average of nine electron-microprobe analyses gave ZnO 58.08, CuO 12.60, PbO 1.27, CO2 (calc.) 19.50, H2O (calc.) 7.94, total 99.39 wt.%, corresponding to the empirical formula (Zn0.62Cu0.36Pb0.01)Σ0.99Zn1.00(CO3)(OH)2. The seven strongest lines in the X-ray powder diffraction pattern are [dhkl in Å (Iobs %, hkl)] 6.054 (67, 200), 5.085 (100, 210), 3.703 (87, 310 and 220), 3.021 (25, 400 and 130), 2.971 (25, -211 and 001), 2.603 (62, -221) and 2.539 (36, 420). According to its X-ray powder diffraction data and chemical formula, parádsasvárite belongs to the malachite-rosasite group and it is isostructural with rosasite. It is monoclinic, space group P21/ a, a = 12.92(1), b = 9.372(7), c = 3.159(4) Å, β = 110.4(1)°, V = 358.5(5) Å3, Z = 4.

  16. EGCG assisted green synthesis of ZnO nanopowders: Photodegradative, antimicrobial and antioxidant activities

    NASA Astrophysics Data System (ADS)

    Suresh, D.; Udayabhanu; Nethravathi, P. C.; Lingaraju, K.; Rajanaika, H.; Sharma, S. C.; Nagabhushana, H.

    2015-02-01

    Zinc oxide nanopowders were synthesized by solution combustion method using Epigallocatechin gallate (EGCG) a tea catechin as fuel. The structure and morphology of the product was characterized by Powder X-ray Diffraction, Scanning Electron Microscopy, photoluminescence and UV-Visible spectroscopy. The nanopowders (Nps) were subjected to photocatalytic and biological activities such as antimicrobial and antioxidant studies. PXRD patterns demonstrate that the formed product belongs to hexagonal wurtzite system. SEM images show that the particles are agglomerated to form sponge like structure and the average crystallite sizes were found to be ∼10-20 nm. PL spectra exhibit broad and strong peak at 590 nm due to the Zn-vacancies, and O-vacancies. The prepared ZnO Nps exhibit excellent photocatalytic activity for the photodegradation of malachite green (MG) and methylene blue (MB) indicating that the ZnO NPs are potential photocatalytic semiconductor materials. ZnO NPs exhibit significant bactericidal activity against Klebsiella aerogenes, Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus using the agar well diffusion method. Furthermore, the ZnO nano powders show good antioxidant activity by potentially scavenging DPPH radicals. The study successfully demonstrates synthesis of ZnO NPs by simple ecofriendly route employing EGCG as fuel that exhibit superior photodegradative, antibacterial and antioxidant activities.

  17. Comparative seasonal sterol profiles in edible parts of Mediterranean fish and shellfish species.

    PubMed

    Ozyurt, Gülsün; Kuley, Esmeray; Etyemez, Miray; Ozoğul, Fatih

    2013-06-01

    The effect of different seasons on sterol content of seafoods was investigated. There were four sterols (cholesterol, sitosterol, desmosterol and stigmasterol) identified, with cholesterol being the predominant sterol. Stigmasterol was a minor component in fish muscle, whilst sitosterol was one of the main phytosterols found in fish muscle. Cholesterol content of fish consisted of 38-100% of total sterols in fish and 54-80% of total sterols in shellfish. The highest cholesterol content of fish muscle was found in summer and the lowest in autumn, whereas season did not have any effect on cholesterol level of green tiger prawn and speckled shrimp. Total sterol content of fish muscle ranged from 49 to 110 mg/100 g, although the range of total sterols in shrimp muscle was between 62 and 91 mg/100 g. The result of the study showed that total sterols in fish were generally found at lower levels in winter compared with other seasons.

  18. Susceptibility of fish to Chattonella marina is determined by its tolerance to hypoxia.

    PubMed

    Shen, Min; Xu, Jingliang; Chan, Alice K Y; Au, Doris W T

    2011-01-01

    The harmful alga Chattonella marina has caused massive fish kills and economic losses worldwide. However, the fish kill mechanisms by C. marina have not been identified. The present study has confirmed that a significant elevation of blood osmolality is the universal response in moribund fish exposed to C. marina and the possible reasons leading to contradictory reports were identified. Both osmotic distress and respiratory impairment are important mechanisms leading to fish kill by C. marina. The susceptibility of marine fish to C. marina appears to be inversely related to their tolerance to hypoxia, with the hypoxia intolerant goldlined seabream being the most susceptible, and the hypoxia tolerant green grouper being the most tolerant to C. marina. Further studies in the marine medaka (Oryzias melastigma) showed that fish susceptibility to C. marina is directly related to susceptibility of the fish to hypoxia, but not related to its tolerance to hypersalinity stress.

  19. Understanding Green Flashes

    NASA Astrophysics Data System (ADS)

    Young, Andrew T.

    1998-05-01

    Most astronomers learn about green flashes from either Minnaert's old book (Dover, 1954) or O'Connell's ``The Green Flash....'' Both have defects. Minnaert's account mostly represents what was known in the 1920s; it repeats Mulder's 3-fold classification, which omits Joule's second type of flash --- the one most commonly seen from mountain observatories. O'Connell searched only the astronomical literature, missing Dietze's crucially important paper (Z.f.Met. 9, 169 (1955)) showing that the ``textbook'' mechanism cannot produce flashes visible to the naked eye. He also erred in thinking that distortions of the setting Sun arise in the upper atmosphere (they are due to the marine boundary layer), and copied an error from Feenstra Kuiper's thesis that misidentified a common mirage-like phenomenon as Wegener's ``blank strip'' (Young et al., Appl. Opt. 36, 2689 (1997).) Most phenomena shown in O'Connell's book are caused by inversion layers below eye level, not above as in Wegener's phenomenon. The two commonest forms of green flash are associated with the inferior mirage and the mock mirage, corresponding to Fisher's Type A and Type B sunsets, respectively. Superrefraction, advocated by Wood and by Rayleigh as the cause of large flashes, actually suppress them: the airmass is proportional to the refraction (by Laplace's extinction theorem), so no green is transmitted when refraction is much larger than average. Although there is a physical green flash that can be photographed, the colors seen at sunset are strongly modified by bleaching of the L cones. Most ``green'' sunset flashes are actually yellow. Writers should stop representing Jules Verne's ``ancient legend'' as fact, as it was invented by Verne as a plot device for his novel ``Le Rayon Vert.'' Green-flash photos and simulations will be shown. This material is based upon work supported by the NSF under Award No. ATM-9714357.

  20. Sensor Fish Communicator

    SciTech Connect

    2016-06-09

    The Sensor Fish collects information that can be used to evaluate conditions encountered by juvenile salmonids and other fish as they pass through hydroelectric dams on their way to the ocean. Sensor Fish are deployed in turbines, spillways, and sluiceways and measure changes in pressure, angular rate of change, and linear acceleration during passage. The software is need to make Sensor Fish fully functional and easy to use. Sensor Fish Communicator (SFC) links to Sensor Fish, allowing users to control data collection settings and download data. It may also be used to convert native raw data (.raw2) files into Comma Separated Variable (.csv) files and plot the results. The multiple capabilities of the SFC allow hardware communication, data conversion, and data plotting with one application.

  1. Immunostimulants in fish diets

    USGS Publications Warehouse

    Gannam, A.L.; Schrock, R.M.

    1999-01-01

    Various immunostimulants and their methods of application in fish culture are examined in this review. Important variables such as life stage and innate disease resistance of the fish; immunostimulant used, its structure and mode of action; and the fish's environment are discussed. Conflicting results have been published about the efficacy of immunostimulants in fish diets. Some researchers have had positive responses demonstrated as increased fish survival, others have not. Generally, immunostimulants enhance individual components of the non-specific immune response but that does not always translate into increased fish survival. In addition, immunostimulants fed at too high a dose or for too long can be immunosuppressive. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: getinfo@haworthpressinc.com ].

  2. Fish and wildlife surveillance

    SciTech Connect

    Poston, T.M.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the monitoring of radioactive contaminants in fish and wildlife species that inhabit the Colombia River and Hanford Site. Wildlife have access to areas of the Site containing radioactive contamination, and fish can be exposed to contamination in spring water entering the river along the shoreline. Therefore, samples are collected at various locations annually, generally during the hunting or fishing season, for selected species.

  3. Hematologic disorders of fish.

    PubMed

    Clauss, Tonya M; Dove, Alistair D M; Arnold, Jill E

    2008-09-01

    Hematology can be a useful tool for monitoring health status, detecting illness, and following the progress of disease and response to therapy. Despite advances in fish medicine in recent years, interpretation of fish hematology often is hampered by a lack of meaningful reference values and the bewildering diversity of fish species. A multitude of intrinsic and extrinsic factors cause normal and abnormal variation in hematologic data. This article provides an overview of some of the hematologic abnormalities in fish induced by infectious agents and environmental, husbandry, and nutritional issues.

  4. [Helminths of Antarctic fishes].

    PubMed

    Rocka, Anna

    2008-01-01

    Antarctic fishes are represented by sharks, skates (Chondrichthyes) and bony fishes (Teleostei). Teleosts play an important role in the completion of life cycles of many helminth species. They serve as either definitive or intermediate and paratenic hosts. Chondrichthyes are definitive hosts only. Seventy three helminth species occur as the adult stage in fishes: Digenea (45), Cestoda (14), Nematoda (6), Acanthocephala (8), Also, 11 larval stages of Cestoda (7) and Nematoda (4) are known, together with 7 species of Acanthocephala in the cystacanth stage. One digenean species, Otodistomum cestoides, matures in skates. Among cestodes maturing in fishes only one, Parabothriocephalus johnstoni, occurs in a bony fish, Macrourus whitsoni. Antarctic Chondrichthyes are not infected with nematodes and acanthocephalans. Cestode larvae from teleosts belong to Tetraphyllidea (parasites of skates), and Tetrabothriidae and Diphyllobothriidae (parasites of birds and mammals). Larval nematodes represent Anisakidae, parasites of fishes, birds and mammals. Acanthocephalan cystacanths mature in pinnipeds and birds. The majority of parasites maturing in Antarctic fishes are endemics. Only 4 digenean and one nematode species, Hysterothylacium aduncum, are cosmopolitan. All acanthocephalans, almost all digeneans, the majority of cestodes and some nematodes occur mainly or exclusively in benthic fishes. Specificity of the majority of helminths utilizing teleosts as intermediate and/or paratenic hosts is low. Among parasites using fishes as definitive hosts, all Cestoda, most Digenea and Nematoda, and almost all Acanthocephala have a range of hosts restricted to one order or even to 1-2 host species.

  5. Evaluation of fast green FCF dye for non-lethal detection of integumental injuries in juvenile chinook salmon oncorhynchus tshawytscha

    USGS Publications Warehouse

    Elliott, D.G.; Conway, C.M.; Applegate, L.M.J.

    2009-01-01

    A rapid staining procedure for detection of recent skin and fin injuries was tested in juvenile Chinook salmon Oncorhynchus tshawytscha. Immersion of anesthetized fish for 1 min in aerated aqueous solutions of the synthetic food dye fast green FCF (Food Green 3) at concentrations of 0.1 to 0.5% produced consistent and visible staining of integumental injuries. A 0.1% fast green concentration was satisfactory for visual evaluation of injuries, whereas a 0.5% concentration was preferable for digital photography. A rinsing procedure comprised of two 30 s rinses in fresh water was most effective for removal of excess stain after exposure of fish. Survival studies in fresh water and seawater and histopathological analyses indicated that short exposures to aqueous solutions of fast green were non-toxic to juvenile Chinook salmon. In comparisons of the gross and microscopic appearance of fish exposed to fast green at various times after injury, the dye was observed only in areas of the body where epidermal disruption was present as determined by scanning electron microscopy. No dye was observed in areas where epidermal integrity had been restored. Further comparisons showed that fast green exposure produced more consistent and intense staining of skin injury sites than a previously published procedure using trypan blue. Because of its relatively low cost, ease of use and the rapid and specific staining of integumental injuries, fast green may find widespread application in fish health and surface injury evaluations. ?? Inter-Research 2009.

  6. Green Logistics Management

    NASA Astrophysics Data System (ADS)

    Chang, Yoon S.; Oh, Chang H.

    Nowadays, environmental management becomes a critical business consideration for companies to survive from many regulations and tough business requirements. Most of world-leading companies are now aware that environment friendly technology and management are critical to the sustainable growth of the company. The environment market has seen continuous growth marking 532B in 2000, and 590B in 2004. This growth rate is expected to grow to 700B in 2010. It is not hard to see the environment-friendly efforts in almost all aspects of business operations. Such trends can be easily found in logistics area. Green logistics aims to make environmental friendly decisions throughout a product lifecycle. Therefore for the success of green logistics, it is critical to have real time tracking capability on the product throughout the product lifecycle and smart solution service architecture. In this chapter, we introduce an RFID based green logistics solution and service.

  7. Fish-allergic patients may be able to eat fish.

    PubMed

    Mourad, Ahmad A; Bahna, Sami L

    2015-03-01

    Reported fish allergy prevalence varies widely, with an estimated prevalence of 0.2% in the general population. Sensitization to fish can occur by ingestion, skin contact or inhalation. The manifestations can be IgE or non-IgE mediated. Several fish allergens have been identified, with parvalbumins being the major allergen in various species. Allergenicity varies among fish species and is affected by processing or preparation methods. Adverse reactions after eating fish are often claimed to be 'allergy' but could be a reaction to hidden food allergen, fish parasite, fish toxins or histamine in spoiled fish. Identifying such causes would allow free consumption of fish. Correct diagnosis of fish allergy, including the specific species, might provide the patient with safe alternatives. Patients have been generally advised for strict universal avoidance of fish. However, testing with various fish species or preparations might identify one or more forms that can be tolerated.

  8. Green Chemistry Pedagogy

    NASA Astrophysics Data System (ADS)

    Kolopajlo, Larry

    2017-02-01

    This chapter attempts to show how the practice of chemistry teaching and learning is enriched by the incorporation of green chemistry (GC) into lectures and labs. To support this viewpoint, evidence from a wide range of published papers serve as a cogent argument that GC attracts and engages both science and nonscience students, enhances chemistry content knowledge, and improves the image of the field, while preparing the world for a sustainable future. Published pedagogy associated with green and sustainable chemistry is critically reviewed and discussed.

  9. Green Supercomputing at Argonne

    ScienceCinema

    Beckman, Pete

    2016-07-12

    Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF) talks about Argonne National Laboratory's green supercomputing—everything from designing algorithms to use fewer kilowatts per operation to using cold Chicago winter air to cool the machine more efficiently. Argonne was recognized for green computing in the 2009 HPCwire Readers Choice Awards. More at http://www.anl.gov/Media_Center/News/2009/news091117.html Read more about the Argonne Leadership Computing Facility at http://www.alcf.anl.gov/

  10. Apollo 15 green glasses.

    NASA Technical Reports Server (NTRS)

    Ridley, W. I.; Reid, A. M.; Warner, J. L.; Brown, R. W.

    1973-01-01

    The samples analyzed include 28 spheres, portions of spheres, and angular fragments from soil 15101. Emerald green glasses from other soils are identical to those from 15101. The composition of the green glass is unlike that of any other major lunar glass group. The Fe content is comparable to that in mare basalts, but Ti is much lower. The Mg content is much higher than in most lunar materials analyzed to date, and the Cr content is also high. The low Al content is comparable to that of mare basalt glasses.

  11. Comparative analysis of teleost fish genomes reveals preservation of different ancient clock duplicates in different fishes.

    PubMed

    Wang, Han

    2008-06-01

    Clock (Circadian locomotor output cycle kaput) was the first vertebrate circadian clock gene identified in a mouse forward genetics mutagenesis screen. It encodes a bHLH-PAS protein that is highly conserved throughout evolution. Tetrapods also have the second Clock gene, Clock2 or Npas2 (Neuronal PAS domain protein 2). Conversely, the fruit fly, an invertebrate, has only one clock gene. Interrogation of the five teleost fish genome databases revealed that the zebrafish and the Japanese pufferfish (fugu) each have three clock genes, whereas the green spotted pufferfish (tetraodon), the Japanese medaka fish and the three-spine stickleback each have two clock genes. Phylogenetic and splice site analyses indicated that zebrafish and fugu each have two clock1 genes, clock1a and clock1b and one clock2; tetraodon also have clock1a and clock1b but do not have clock2; and medaka and stickleback each have clock1b and one clock2. Genome neighborhood analysis further showed that clock1a/clock1b in zebrafish, fugu and tetraodon is an ancient duplicate. While the dN/dS ratios of these three fish clock duplicates are all <1, indicating that purifying selection has acted upon them; the Tajima relative rate test showed that all three fish clock duplicates have asymmetric evolutionary rates, implicating that one of these duplicates have been under positive selection or relaxed functional constraint. These results support the view that teleost fish clock genes were generated from an ancient genome-wide duplication, and differential gene loss after the duplication resulted in retention of different ancient duplicates in different teleost fishes, which could have contributed to the evolution of the distinct fish circadian clock mechanisms.

  12. An Amazing Fish Story.

    ERIC Educational Resources Information Center

    Null, Elisabeth Higgins

    2001-01-01

    Caught up in the entrepreneurial thrill of launching a new industry, high-school students in an economically distressed fishing village in Maine are playing a vital research-and-development role in partnership with their community. The result is a sophisticated aquaculture center for raising several species of fish in a laboratory setting. (MLH)

  13. PARASITES OF FISH

    EPA Science Inventory

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  14. Folkbiology of Freshwater Fish

    ERIC Educational Resources Information Center

    Medin, Douglas L.; Ross, Norbert O.; Atran, Scott; Cox, Douglas; Coley, John; Proffitt, Julia B.; Blok, Sergey

    2006-01-01

    Cross-cultural comparisons of categorization often confound cultural factors with expertise. This paper reports four experiments on the conceptual behavior of Native American and majority-culture fish experts. The two groups live in the same general area and engage in essentially the same set of fishing-related behaviors. Nonetheless, cultural…

  15. Fishing for Environmental Education.

    ERIC Educational Resources Information Center

    Matthews, Bruce

    1994-01-01

    Fishing helps campers develop problem-solving skills, apply biological and ecological concepts, become aware of environmental problems, realize environmental consequences of actions, discuss environmental ethics, consider spiritual values, and connect with the natural world. Describes two camps that successfully integrate fishing with…

  16. The Big Fish

    ERIC Educational Resources Information Center

    DeLisle, Rebecca; Hargis, Jace

    2005-01-01

    The Killer Whale, Shamu jumps through hoops and splashes tourists in hopes for the big fish, not because of passion, desire or simply the enjoyment of doing so. What would happen if those fish were obsolete? Would this killer whale be able to find the passion to continue to entertain people? Or would Shamu find other exciting activities to do…

  17. Sensitivity of juvenile striped bass to chemicals used in aquaculture

    SciTech Connect

    Bills, T.D.; Marking, L.L.; Howe, G.E.

    1993-01-01

    Efforts to restore anadromous striped bass (Morone saxatilis) populations by the U.S. Fish and Wildlife Service and other agencies over the past 20 years have concentrated on hatchery culture to supplement dwindling natural reproduction. Adult fish captured for artificial spawning are stressed by handling and crowding in rearing ponds and are often exposed to therapeutants, anesthetics, disinfectants, and herbicides used in fish culture. The authors determined the toxicity of 17 fishery chemicals (chloramine-T, erythromycin, formalin, Hyamine 3500, Roccal, malachite green, sulfamerazine, benzocaine, etomidate, Finquel (MS-222), metomidate, quinaldine sulfate, chlorine, potassium permanganate, Aquazine, copper sulfate, and Rodeo) to striped bass fry (average weight = 1 g) in reconstituted water (total hardness 40 mg/L) at 12 degrees C. The 96-h LC50's (concentration calculated to produce 50% mortality in a population) ranged from 0.129 mg/L for malachite green to 340 mg/L for erythromycin.

  18. Antimicrobial Peptides from Fish

    PubMed Central

    Masso-Silva, Jorge A.; Diamond, Gill

    2014-01-01

    Antimicrobial peptides (AMPs) are found widely distributed through Nature, and participate in the innate host defense of each species. Fish are a great source of these peptides, as they express all of the major classes of AMPs, including defensins, cathelicidins, hepcidins, histone-derived peptides, and a fish-specific class of the cecropin family, called piscidins. As with other species, the fish peptides exhibit broad-spectrum antimicrobial activity, killing both fish and human pathogens. They are also immunomodulatory, and their genes are highly responsive to microbes and innate immuno-stimulatory molecules. Recent research has demonstrated that some of the unique properties of fish peptides, including their ability to act even in very high salt concentrations, make them good potential targets for development as therapeutic antimicrobials. Further, the stimulation of their gene expression by exogenous factors could be useful in preventing pathogenic microbes in aquaculture. PMID:24594555

  19. Small nonnative fishes as predators of larval razorback suckers

    USGS Publications Warehouse

    Carpenter, J.; Mueller, G.A.

    2008-01-01

    The razorback sucker (Xyrauchen texanus), an endangered big-river fish of the Colorado River basin, has demonstrated no sustainable recruitment in 4 decades, despite presence of spawning adults and larvae. Lack of adequate recruitment has been attributed to several factors, including predation by nonnative fishes. Substantial funding and effort has been expended on mechanically removing nonnative game fishes, typically targeting large predators. As a result, abundance of larger predators has declined, but the abundance of small nonnative fishes has increased in some areas. We conducted laboratory experiments to determine if small nonnative fishes would consume larval razorback suckers. We tested adults of three small species (threadfin shad, Dorosoma petenense; red shiner, Cyprinella lutrensis; fathead minnow, Pimephales promelas) and juveniles of six larger species (common carp, Cyprinus carpio; yellow bullhead, Ameiurus natalis; channel catfish, Ictalurus punctatus; rainbow trout, Oncorhynchus mykiss; green sunfish, Lepomis cyanellus; bluegill, L. macrochirus). These nonnative fishes span a broad ecological range and are abundant within the historical range of the razorback sucker. All nine species fed on larval razorback suckers (total length, 9-16 mm). Our results suggest that predation by small nonnative fishes could be responsible for limiting recovery of this endangered species.

  20. Comparative genomic analysis of teleost fish bmal genes.

    PubMed

    Wang, Han

    2009-05-01

    Bmal1 (Brain and muscle ARNT like 1) gene is a key circadian clock gene. Tetrapods also have the second Bmal gene, Bmal2. Fruit fly has only one bmal1/cycle gene. Interrogation of the five teleost fish genome sequences coupled with phylogenetic and splice site analyses found that zebrafish have two bmal1 genes, bmal1a and bmal1b, and bmal2a; Japanese pufferfish (fugu), green spotted pufferfish (tetraodon) and Japanese medaka fish each have two bmal2 genes, bmal2a and bmal2b, and bmal1a; and three-spine stickleback have bmal1a and bmal2b. Syntenic analysis further indicated that zebrafish bmal1a/bmal1b, and fugu, tetraodon and medaka bmal2a/bmal2b are ancient duplicates. Although the dN/dS ratios of these four fish bmal duplicates are all <1, implicating they have been under purifying selection, the Tajima relative rate test showed that fugu, tetraodon and medaka bmal2a/bmal2b have asymmetric evolutionary rates, suggesting that one of these duplicates have been subject to positive selection or relaxed functional constraint. These results support the notion that teleost fish bmal genes were derived from the fish-specific genome duplication (FSGD), divergent resolution following the duplication led to retaining different ancient bmal duplicates in different fishes, which could have shaped the evolution of the complex teleost fish timekeeping mechanisms.

  1. Relation of urbanization to stream fish assemblages and species traits in nine metropolitan areas of the United States

    USGS Publications Warehouse

    Brown, Larry R.; Gregory, M. Brian; May, Jason T.

    2009-01-01

    We examined associations of fish assemblages and fish traits with urbanization and selected environmental variables in nine major United States metropolitan areas. The strongest relations between fishes and urbanization occurred in the metropolitan areas of Atlanta, Georgia; Birmingham, Alabama; Boston, Massachusetts; and Portland, Oregon. In these areas, environmental variables with strong associations (rs ≥ 0.70) with fish assemblages and fish traits tended to have strong associations with urbanization. Relations of urbanization with fish assemblages and fish traits were weaker in Denver, Colorado; Dallas-Fort Worth, Texas; Milwaukee-Green Bay, Wisconsin; and Raleigh, North Carolina. Environmental variables associated with fishes varied among the metropolitan areas. The metropolitan areas with poor relations may have had a limited range of possible response because of previous landscape disturbances. Given the complexities of urban landscapes in different metropolitan areas, our results indicate that caution is warranted when generalizing about biological responses to urbanization.

  2. Greening America's Capitals - Charleston, WV

    EPA Pesticide Factsheets

    This Greening America’s Capitals report outlines design concepts that could improve Slack Plaza in Charleston, WV, by creating more opportunities for local businesses, better managing stormwater runoff, and increasing green space.

  3. Green Building Tools for Tribes

    EPA Pesticide Factsheets

    Tribal green building tools and funding information to support tribal building code adoption, healthy building, siting, energy efficiency, renewable energy, water conservation, green building materials, recycling and adaptation and resilience.

  4. Become a Green Power Partner

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Learn more about becoming a Green Power Partner, including recognition opportunities.

  5. Benefits of Green Power Partnership

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary partnership program designed to reduce the environmental impact of electricity generation by promoting renewable energy. Learn about the benefits of becoming a Green Power Partner.

  6. Green Power Partnership Program Initiatives

    EPA Pesticide Factsheets

    EPA's Green Power Partnership has a number of initiatives that focus on the collective green power efforts within specific sectors and renewable energy procurement strategies, which provide recognition opportunities for Partners and increase awareness.

  7. Green Power Partnership Resource Eligibility

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary partnership program designed to reduce the environmental impact of electricity generation by promoting renewable energy. This page details the resources EPA considers eligible green power.

  8. Partnership Green Power Use Requirements

    EPA Pesticide Factsheets

    The U.S. EPA's Green Power Partnership is a voluntary partnership program designed to reduce the environmental impact of electricity generation by promoting renewable energy. This pages details green power use requirements for Partnership.

  9. The Green Obligation

    ERIC Educational Resources Information Center

    Adams, Cameron

    2007-01-01

    As the green movement grows, studies provide conclusive evidence about the benefits of environmentally conscious practices indoors and outdoors. Schools are no exception. Many of these studies demonstrate how poor indoor air quality (IAQ) in schools adversely affects many of the nation's 55 million students with health problems such as asthma and…

  10. Green chemistry metrics

    EPA Science Inventory

    Synthetic chemists have always had an objective to achieve reliable and high-yielding routes to the syntheses of targeted molecules. The importance of minimal waste generation has emphasized the use of green chemistry principles and sustainable development. These directions lead ...

  11. Toward Green Challenge Courses.

    ERIC Educational Resources Information Center

    Johnson, Karl E.

    1999-01-01

    Designing environmentally friendly challenge courses involves considering factors such as clearing, trees versus poles, soil erosion and compaction, toilet design, waste disposal, and carrying capacity. Strategies used in "green development" such as systems thinking, solution multipliers, and brainstorming with stakeholders could promote…

  12. Putting on the green

    EPA Science Inventory

    The green chemistry movement is scrutinized for marks of tangible success in this short perspective. Beginning with the easily identified harm of the Union Carbide Bhopal, India disaster and the concerns of Love Canal site in Niagara Falls, NY the public can begin to more easily ...

  13. Raising a "Green Generation"

    ERIC Educational Resources Information Center

    Leger-Ferraro, Susan

    2010-01-01

    These days, "going green" is at the forefront of conversation in political, entertainment, and corporate circles. Yet to truly impact change, future generations must carry the torch of transformation. To ensure success, adults need to begin the practices with the fertile minds of young children in early education. Practicing sustainability is not…

  14. A Green Role Model

    ERIC Educational Resources Information Center

    Hoffman, Paul J.

    2008-01-01

    Building a new green campus and adopting a philosophy of sustainability is exciting, but if not done properly, it is not always the wisest decision. As one considers the education, health, and safety of a campus community, along with its business objectives, one may discover that there are numerous ways to make the campus more sustainable without…

  15. Green Schools: Electric Youth

    ERIC Educational Resources Information Center

    Demski, Jennifer

    2008-01-01

    A student committee whose main duty is changing light bulbs may sound like the punch line to a bad joke, but as the students and faculty at Montgomery County Public Schools (MCPS) in Rockville, MD, know, changing a light bulb is no laughing matter. As part of the district's green initiative, all standard incandescent and fluorescent light bulbs…

  16. Green Supercomputing at Argonne

    ScienceCinema

    Pete Beckman

    2016-07-12

    Pete Beckman, head of Argonne's Leadership Computing Facility (ALCF) talks about Argonne National Laboratory's green supercomputing—everything from designing algorithms to use fewer kilowatts per operation to using cold Chicago winter air to cool the machine more efficiently.

  17. Elements of Green.

    ERIC Educational Resources Information Center

    Turckes, Steven; Engelbrecht, Kathie

    2002-01-01

    Discusses incorporating green design into school construction, asserting that schools can improve their impact on the environment and reduce their operating costs while educating people about the value of sustainable design. Addresses energy reduction (including daylighting), site design for low environmental impact, flexible design, indoor air…

  18. News: Green Chemistry & Technology

    EPA Science Inventory

    A series of 21 articles focused on different features of green chemistry in a recent issue of Chemical Reviews. Topics extended over a wide range to include the design of sustainable synthetic processes to biocatalysis. A selection of perspectives follows as part of this colu

  19. The Green Hunter.

    ERIC Educational Resources Information Center

    Reid, Ed

    1991-01-01

    Environmentalists who oppose hunting have little understanding of the sport, its ethics and regulations, and its immense role in wildlife conservation. "Green" hunting involves not only the hunter's methods but also his perceptions of the hunt as a cultural or spiritual experience. (SV)

  20. The Green Team

    ERIC Educational Resources Information Center

    Jahnigen, Charlie

    2006-01-01

    As interest in green building grows, much discussion has focused on aligning a project with the principles of Leadership in Energy and Environmental Design (LEED) certification: (1) cost savings through energy and water conservation; (2) improved worker productivity; (3) health, insurance and risk-management benefits; and (4) enhanced building…

  1. Lean Green Machines

    ERIC Educational Resources Information Center

    Villano, Matt

    2011-01-01

    Colleges and universities have been among the leaders nationwide in adopting green initiatives, partly due to their demographics, but also because they are facing their own budget pressures. Virtualization has become the poster child of many schools' efforts, because it provides significant bang for the buck. However, more and more higher…

  2. The green highway forum

    SciTech Connect

    2006-07-01

    In late 2004, as part of American Coal Ash Association's (ACAA) strategic planning process, a plan was approved by its Board of Directors implementing a 'green highways' concept which emphasized use of coal combustion products (CCPs) in highways in a variety of ways including being used alone, in combination with other forms of CCPs, and combined with non ash materials. The incentives behind the developed concept were the derived advantages from beneficial technical economic and environmental impacts. Although the primary use of fly ash is concrete, other forms of CCPs could be considered for more non-traditional highway applications. For example, these might include soils stabilization, binders for in-place pavement recycling, use in flowable fills, aggregates, source materials for structural fills and embankments, components in manufactured soils, and for granular base courses beneath pavements. At this same time, unknown to ACCA, EPA Region 3 in Philadelphia was working with the Wetlands and Watershed Work Group, a non-profit organization involved in wetlands policy and management along with the Federal Highway Administration (FHWA) on their own Green Highways initiative. These groups were planning a conference, the 'Green Highway Forum'. This was held in College Park, Maryland at the University of Maryland, Nov 8-10 2005. At the conference a draft 'roadmap' was presented as a guide to executive level participants bringing the diverse viewpoints of many agencies and interest groups together. Ten guiding principals were considered. The 'Green Highways' is a new effort to recognize the 'greenness' of many projects already completed and those to be initiated. 2 photos.

  3. 50 CFR 223.210 - Green sturgeon.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Department of Fish and Game, Oregon Department of Fish and Wildlife, Washington Department of Fish and Wildlife, or Alaska Department of Fish and Game; (iii) The activity benefits the Southern DPS; and (iv... Department of Fish and Game, Oregon Department of Fish and Wildlife, Washington Department of Fish...

  4. Green Power Partnership Events and Webinars

    EPA Pesticide Factsheets

    EPA's Green Power Partnership hosts variety of events, such as webinars and presentations at conferences, on a regular basis. Topics include the Green Power Partnership, green power technologies and products, and information on procuring green power.

  5. Green Roofs for Stormwater Management

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  6. Green Schools on Ordinary Budgets

    ERIC Educational Resources Information Center

    Hanson, Mark E.

    2010-01-01

    Some in the green building industry have spoken for some time now of green buildings not needing to cost more. Jason McLennan in his 2004 book "The Philosophy of Sustainable Design" discusses not falling into the "green is always more" syndrome. He goes on to explain the concept of tunneling through the cost barrier. A 2007…

  7. Guide to Purchasing Green Power

    EPA Pesticide Factsheets

    The Guide for Purchasing Green Power is a comprehensive guide for current and potential buyers of green power with information about green power purchasing. The Guide is created cooperatively between the EPA, the U.S. Department of Energy, the World Resou

  8. "Green" School Programs. Research Brief

    ERIC Educational Resources Information Center

    Johnston, J. Howard

    2009-01-01

    What are "Green School" programs and how do they benefit students, teachers and the community? Green School programs seek to weave concepts of sustainability and environmental awareness into the social and academic culture of the school community. Green schools are high performance facilities that have been designed, built, renovated operated or…

  9. It's Not Easy Building Green.

    ERIC Educational Resources Information Center

    Higgins, Joseph

    2003-01-01

    Discusses green buildings, facilities designed, constructed, and operated in an environmentally friendly and resource-efficient way. Discusses reasons for campuses to "go green," the "shades of green" or variations in environmental-friendliness, certification through the Leadership in Energy and Environmental Design (LEED) rating system, financial…

  10. Greening from the Top Down.

    ERIC Educational Resources Information Center

    Oberndorfer, Erica

    2002-01-01

    Green roofs, with their topsoil and plants, improve insulation, filter air, reduce water runoff, and provide habitat for urban wildlife. They are compatible with schools because they save energy; schools' flat roofs are conducive to greening; and green roofs can be outdoor classrooms for botany, ecology, and energy efficiency. Although scarce in…

  11. Folkbiology of freshwater fish.

    PubMed

    Medin, Douglas L; Ross, Norbert O; Atran, Scott; Cox, Douglas; Coley, John; Proffitt, Julia B; Blok, Sergey

    2006-04-01

    Cross-cultural comparisons of categorization often confound cultural factors with expertise. This paper reports four experiments on the conceptual behavior of Native American and majority-culture fish experts. The two groups live in the same general area and engage in essentially the same set of fishing-related behaviors. Nonetheless, cultural differences were consistently observed. Majority-culture fish experts tended to sort fish into taxonomic and goal-related categories. They also showed an influence of goals on probes of ecological relations, tending to answer in terms of relations involving adult fish. Native American fish experts, in contrast, were more likely to sort ecologically. They were also more likely to see positive and reciprocal ecological relations, tending to answer in terms of relations involving the full life cycle of fish. Further experiments support the view that the cultural differences do not reflect different knowledge bases but rather differences in the organization and accessibility of knowledge. At a minimum the results suggest that similar activities within a well-structured domain do not necessarily lead to common conceptualizations.

  12. Epigenomics in marine fishes.

    PubMed

    Metzger, David C H; Schulte, Patricia M

    2016-12-01

    Epigenetic mechanisms are an underappreciated and often ignored component of an organism's response to environmental change and may underlie many types of phenotypic plasticity. Recent technological advances in methods for detecting epigenetic marks at a whole-genome scale have launched new opportunities for studying epigenomics in ecologically relevant non-model systems. The study of ecological epigenomics holds great promise to better understand the linkages between genotype, phenotype, and the environment and to explore mechanisms of phenotypic plasticity. The many attributes of marine fish species, including their high diversity, variable life histories, high fecundity, impressive plasticity, and economic value provide unique opportunities for studying epigenetic mechanisms in an environmental context. To provide a primer on epigenomic research for fish biologists, we start by describing fundamental aspects of epigenetics, focusing on the most widely studied and most well understood of the epigenetic marks: DNA methylation. We then describe the techniques that have been used to investigate DNA methylation in marine fishes to date and highlight some new techniques that hold great promise for future studies. Epigenomic research in marine fishes is in its early stages, so we first briefly discuss what has been learned about the establishment, maintenance, and function of DNA methylation in fishes from studies in zebrafish and then summarize the studies demonstrating the pervasive effects of the environment on the epigenomes of marine fishes. We conclude by highlighting the potential for ongoing research on the epigenomics of marine fishes to reveal critical aspects of the interaction between organisms and their environments.

  13. Olfactory toxicity in fishes.

    PubMed

    Tierney, Keith B; Baldwin, David H; Hara, Toshiaki J; Ross, Peter S; Scholz, Nathaniel L; Kennedy, Christopher J

    2010-01-21

    Olfaction conveys critical environmental information to fishes, enabling activities such as mating, locating food, discriminating kin, avoiding predators and homing. All of these behaviors can be impaired or lost as a result of exposure to toxic contaminants in surface waters. Historically, teleost olfaction studies have focused on behavioral responses to anthropogenic contaminants (e.g., avoidance). More recently, there has been a shift towards understanding the underlying mechanisms and functional significance of contaminant-mediated changes in fish olfaction. This includes a consideration of how contaminants affect the olfactory nervous system and, by extension, the downstream physiological and behavioral processes that together comprise a normal response to naturally occurring stimuli (e.g., reproductive priming or releasing pheromones). Numerous studies spanning several species have shown that ecologically relevant exposures to common pollutants such as metals and pesticides can interfere with fish olfaction and disrupt life history processes that determine individual survival and reproductive success. This represents one of the pathways by which toxic chemicals in aquatic habitats may increasingly contribute to the decline and at-risk status of many commercially and ecologically important fish stocks. Despite our emerging understanding of the threats that pollution poses for chemical communication in aquatic communities, many research challenges remain. These include: (1) the determination of specific mechanisms of toxicity in the fish olfactory sensory epithelium; (2) an understanding of the impacts of complex chemical mixtures; (3) the capacity to assess olfactory toxicity in fish in situ; (4) the impacts of toxins on olfactory-mediated behaviors that are still poorly understood for many fish species; and (5) the connections between sublethal effects on individual fish and the long-term viability of wild populations. This review summarizes and integrates

  14. Which Fish Should I Eat? Perspectives Influencing Fish Consumption Choices

    PubMed Central

    Choi, Anna L.; Karagas, Margaret R.; Mariën, Koenraad; Rheinberger, Christoph M.; Schoeny, Rita; Sunderland, Elsie; Korrick, Susan

    2012-01-01

    Background: Diverse perspectives have influenced fish consumption choices. Objectives: We summarized the issue of fish consumption choice from toxicological, nutritional, ecological, and economic points of view; identified areas of overlap and disagreement among these viewpoints; and reviewed effects of previous fish consumption advisories. Methods: We reviewed published scientific literature, public health guidelines, and advisories related to fish consumption, focusing on advisories targeted at U.S. populations. However, our conclusions apply to groups having similar fish consumption patterns. Discussion: There are many possible combinations of matters related to fish consumption, but few, if any, fish consumption patterns optimize all domains. Fish provides a rich source of protein and other nutrients, but because of contamination by methylmercury and other toxicants, higher fish intake often leads to greater toxicant exposure. Furthermore, stocks of wild fish are not adequate to meet the nutrient demands of the growing world population, and fish consumption choices also have a broad economic impact on the fishing industry. Most guidance does not account for ecological and economic impacts of different fish consumption choices. Conclusion: Despite the relative lack of information integrating the health, ecological, and economic impacts of different fish choices, clear and simple guidance is necessary to effect desired changes. Thus, more comprehensive advice can be developed to describe the multiple impacts of fish consumption. In addition, policy and fishery management inter-ventions will be necessary to ensure long-term availability of fish as an important source of human nutrition. PMID:22534056

  15. Early detection of non-native fishes using fish larvae

    EPA Science Inventory

    Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection. First,...

  16. Green tea and cancer prevention.

    PubMed

    Yang, Chung S; Wang, Xin

    2010-01-01

    Extracts of green tea and green tea polyphenols have exhibited inhibitory effects against the formation and development of tumors at different organ sites in animals. These include animal models for skin, lung, oral cavity, esophagus, stomach, intestine, colon, liver, pancreas, bladder, mammary gland, and prostate cancers. In addition to suppressing cell proliferation, promoting apoptosis, and modulating signaling transduction, green tea polyphenols, especially (-)-epigallocatechin-3-gallate, also inhibit cell invasion, angiogenesis, and metastasis. This article reviews data on the cancer preventive activities of green tea polyphenols, possible mechanisms involved, and the relationship between green tea consumption and human cancer risk.

  17. Green Luminescent Copper Nanoparticles

    NASA Astrophysics Data System (ADS)

    Suresh, Y.; Annapurna, S.; Bhikshamaiah, G.; Singh, A. K.

    2016-09-01

    Copper nanoparticles are synthesized by a green chemical reduction method using Gum Kondagogu extract as stabilizer. The as-prepared powder samples are characterized by Transmission Electron Microscopy (TEM), Small Angle X-Ray Scattering (SAXS), UV-Visible Spectroscopy, X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. The as-prepared copper nanoparticles are found to be FCC crystalline and nearly monodispersed with particles size 19 nm. Photoluminescence (PL) measurement showed strong green visible emission and PL intensity was found enhanced with the presence of natural extract on copper nanoparticle surface. The increase in the PL intensity was mainly due to copper nanoparticles. Photoluminescence spectra of copper nanoparticles show an emission peak at 430 nm when illuminated at 325 nm.

  18. Green biorefinery - Industrial implementation.

    PubMed

    Kamm, B; Schönicke, P; Hille, Ch

    2016-04-15

    Oil refineries currently generate a multitude of products for almost every sphere of life at very high efficiency. However, fossil raw materials are just available in limited quantities. The development of comparable BIOREFINERIES is necessary to make a variety of competitive biological products regarding their equivalent products based on fossil raw materials. The product range of a biorefinery comprises products that can be manufactured on the basis of crude oil, as well as such products that cannot be produced on the basis of crude oil (Kamm, Gruber, & Kamm, 2011). GREEN BIOREFINERIES [GBR's] are complex systems of sustainable, environment- and resource-friendly technologies for a comprehensive material and energy use or recovery of renewable raw materials in form of green and waste biomasses from a sustainable land use as target (Kamm et al., 2009; Digman, Runge, Shinners, & Hatfield, 2013).

  19. Magnetic fields of green.

    PubMed

    Branton, Scott; Lile, Lawrence

    2011-01-01

    By incorporating even the basic elements of a more environmentally friendly, "green"construction and design in an MRI setting can create a safer, more pleasant space for the patients and staff, better images, and operational cost savings. Using building systems that have reduced amounts of steel can decrease construction time, increase thermal insulation, and reduce the weight of the structure meaning less energy required to transport and install. HVAC systems and lighting design can also play a major role in creating a "green"MRI suite. LEED certification places a focus on quality of the built environment, life cycle cost, and a productive indoor environment, as well as impact on the exterior environment. An LEED certified building considers costs and benefits for the lifetime of the building.

  20. Ciguatera Fish Poisoning

    MedlinePlus

    ... be adversely affected by toxic or harmful marine algae. + Causative algae implicated, not confirmed. Medical Community Ciguatera Fish Poisoning ... Contact Us | Related Links | Site Map The Harmful Algae Page is supported by a National Oceanic and ...

  1. Dehydrofreezing of Fish I

    NASA Astrophysics Data System (ADS)

    Kozima, Tsuneo

    Recently, new method of removing water from perishable food were developed using dehydration sheet with material having high osmotic pressure and absorbent polymer. Dehydration sheet consist of mixture of sugar dehydrolysate and absorbent polymer covered with sem-permeable membrane, and can remove water in liquid state by contact with perishable food. Dehydration rate of fish using with dehydration sheet varied depending on species, their shape, and ambient temperature etc. Fish were dehydrated with dehydration sheet at low temperature as 0 - 5 C and frozen in cold storage room. Dehydrofrozen fish were kept it's high quality and freshness after thawing, ATPase activity of fish muscle was kept at high level after dehydrofreezing in the case of cod and alaska pollack, and flesh color of farming salmon was kept after thawing.

  2. All fish for China?

    PubMed

    Villasante, Sebastián; Rodríguez-González, David; Antelo, Manel; Rivero-Rodríguez, Susana; de Santiago, José A; Macho, Gonzalo

    2013-12-01

    In this paper we examine the effect of Gross Domestic Product (GDP) on the level of fish intake in China in comparison with the rest of the world. We also analyse the origin and destination of China's seafood products in order to understand the main patterns during the last decades. The results show that in the 1961-2011 period the rate of growth of the GDP in China doubled that of other developing regions, while the daily fish intake of China increased fourfold, making China the largest fish consumer in the world. Given the size and scale of China's role in production, consumption, and global transformation of seafood markets, China is shaping a new era of industrialization in the history of the fishing industry.

  3. Fishing for Seeds.

    ERIC Educational Resources Information Center

    Science and Children, 2001

    2001-01-01

    Describes a method to collect seeds that are dispersed from weeds while avoiding some outdoor hazards such as rough terrain or animals. Describes a plan for creating a weed fishing pole and includes a materials list. (SAH)

  4. Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

    PubMed

    Bergman, Paul S; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods.

  5. Detection of Adult Green Sturgeon Using Environmental DNA Analysis

    PubMed Central

    Bergman, Paul S.; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California’s Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods. PMID:27096433

  6. Green Arctic Patrol Vessel

    DTIC Science & Technology

    2010-10-01

    design with a full load displacement of 6,480 long tons. The vessel was outfitted with a towed sonary array, surface and air radar, and a small...and system complexity. 15. SUBJECT TERMS Arctic patrol, green technology, environment, polution , ship design, CISD, fuel cell 16. SECURITY...was outfitted with a towed sonary array, surface and air radar, and a small interdiction and rescue craft. In anticipation of more stringent

  7. Green chemistry: development trajectory

    NASA Astrophysics Data System (ADS)

    Moiseev, I. I.

    2013-07-01

    Examples of applications of green chemistry methods in heavy organic synthesis are analyzed. Compounds, which can be produced by the processing of the biomass, and the criteria for the selection of the most promising products are summarized. The current status of the ethanol production and processing is considered. The possibilities of the use of high fatty acid triglycerides, glycerol, succinic acid, and isoprene are briefly discussed. The bibliography includes 67 references.

  8. Food and feeding of fish in Hartwell Reservoir tailwater, Georgia-South Carolina

    USGS Publications Warehouse

    Barwick, D. Hugh; Hudson, Patrick L.

    1985-01-01

    Food of silver redhorse (Moxostoma anisurum), redbreast sunfish (Lepomis auritus), green sunfish (L. cyanellus), and bluegills (L. macrochirus) was examined to determine whether or not these fish in the Hartwell Reservoir tailwater (Savannah River, Georgia-South Carolina) ate organisms entrained from the reservoir or displaced from the tailwater during water releases associated with the production of hydropower. These fish fed primarily on aquatic insects, crayfish, and terrestrial organisms originating from the tailwater. Major periods of feeding occurred during nongeneration.

  9. The Green`s function method for critical heterogeneous slabs

    SciTech Connect

    Kornreich, D.E.

    1996-10-01

    Recently, the Green`s Function Method (GFM) has been employed to obtain benchmark-quality results for nuclear engineering and radiative transfer calculations. This was possible because of fast and accurate calculations of the Green`s function and the associated Fourier and Laplace transform inversions. Calculations have been provided in one-dimensional slab geometries for both homogeneous and heterogeneous media. A heterogeneous medium is analyzed as a series of homogeneous slabs, and Placzek`s lemma is used to extend each slab to infinity. This allows use of the infinite medium Green`s function (the anisotropic plane source in an infinite homogeneous medium) in the solution. To this point, a drawback of the GFM has been the limitation to media with c < 1, where c is the number of secondary particles produced in a collision. Clearly, no physical steady-state solution exists for an infinite medium that contains an infinite source and is described by c >1; however, mathematical solutions exist which result in oscillating Green`s functions. Such calculations are briefly discussing. The limitation to media with c < 1 has been relaxed so that the Green`s function may also be calculated for media with c {ge} 1. Thus, materials that contain fissionable isotopes may be modeled.

  10. A green process to prepare chromic oxide green pigment.

    PubMed

    Li, Ping; Xu, Hong-Bin; Zheng, Shi-Li; Zhang, Yi; Li, Zuo-Hu; Bai, Yu-Lan

    2008-10-01

    A hydrogen reduction and activated sintering process was proposed to prepare chromic oxide green pigment. Through ICP, XRD, SEM, FT-IR, UV, and CIE-L*a*b* colorimetric analysis, key factors and mechanism that influenced preparation of chromic oxide green pigment were studied. The results revealed that lower hydrogen reduction temperature, suitable addition of Al and Ba, were beneficial to obtaining the high quality chromic oxide green pigment. Typically, when the hydrogen reduction temperature was kept at 450-500 degrees C, physicochemical properties and color performance of the prepared chromic oxide green pigment doped with about 0.1-0.2 wt % Al and 0.2-0.5 wt % Ba conformed to commercial pigment standards. Additionally, characteristics of the green process were discussed. About 90 wt % KOH was reused directly and about 90 wt % Cr(VI) was conversed to Cr(III) directly from potassium chromate to chromic oxide green pigment. Integrating the proprietary green metallurgical process from chromite ore to potassium chromate of this laboratory, more than 99 wt % Cr(VI) could be conversed to Cr(III) compounds and about 99 wt % KOH could be recycled to use. The whole green process, ranging from chromite ore to chromic oxide green pigment, eventually not only provided the possibility for producing the high quality chromic oxide green pigment, but could reach comprehensive utilization of resources, inner recycle of KOH, and zero emission of Cr(VI).

  11. T Cells in Fish

    PubMed Central

    Nakanishi, Teruyuki; Shibasaki, Yasuhiro; Matsuura, Yuta

    2015-01-01

    Cartilaginous and bony fish are the most primitive vertebrates with a thymus, and possess T cells equivalent to those in mammals. There are a number of studies in fish demonstrating that the thymus is the essential organ for development of T lymphocytes from early thymocyte progenitors to functionally competent T cells. A high number of T cells in the intestine and gills has been reported in several fish species. Involvement of CD4+ and CD8α+ T cells in allograft rejection and graft-versus-host reaction (GVHR) has been demonstrated using monoclonal antibodies. Conservation of CD4+ helper T cell functions among teleost fishes has been suggested in a number studies employing mixed leukocyte culture (MLC) and hapten/carrier effect. Alloantigen- and virus-specific cytotoxicity has also been demonstrated in ginbuna and rainbow trout. Furthermore, the important role of cell-mediated immunity rather than humoral immunity has been reported in the protection against intracellular bacterial infection. Recently, the direct antibacterial activity of CD8α+, CD4+ T-cells and sIgM+ cells in fish has been reported. In this review, we summarize the recent progress in T cell research focusing on the tissue distribution and function of fish T cells. PMID:26426066

  12. Cleaner fish drives local fish diversity on coral reefs.

    PubMed

    Grutter, Alexandra S; Murphy, Jan Maree; Choat, J Howard

    2003-01-08

    Coral reefs are one of the most diverse habitats in the world, yet our understanding of the processes affecting their biodiversity is limited. At the local scale, cleaner fish are thought to have a disproportionate effect, in relation to their abundance and size, on the activity of many other fish species, but confirmation of this species' effect on local fish diversity has proved elusive. The cleaner fish Labroides dimidiatus has major effects on fish activity patterns and may indirectly affect fish demography through the removal of large numbers of parasites. Here we show that small reefs where L. dimidiatus had been experimentally excluded for 18 months had half the species diversity of fish and one-fourth the abundance of individuals. Only fish that move among reefs, however, were affected. These fish include large species that themselves can affect other reef organisms. In contrast, the distribution of resident fish was not affected by cleaner fish. Thus, many fish appear to choose reefs based on the presence of cleaner fish. Our findings indicate that a single small and not very abundant fish has a strong influence on the movement patterns, habitat choice, activity, and local diversity and abundance of a wide variety of reef fish species.

  13. INL Green Building Strategy

    SciTech Connect

    Jennifer Dalton

    2005-05-01

    Green buildings, also known as sustainable buildings, resource efficient buildings, and high performance buildings, are structures that minimize the impact on the environment by using less energy and water, reducing solid waste and pollutants, and limiting the depletion of natural resources. As Idaho National Laboratory (INL) becomes the nation’s premier nuclear energy research laboratory, the physical infrastructure will be established to help accomplish the mission. This infrastructure, particularly the buildings, should incorporate green design features in order to be environmentally responsible and reflect an image of progressiveness and innovation to the public and prospective employees. With this in mind, the recommendations described in this strategy are intended to form the INL foundation for green building standards. The recommendations in this strategy are broken down into three levels: Baseline Minimum, Leadership in Energy and Environmental Design (LEED)Certification, and Innovative. Baseline Minimum features should be included in all new occupied buildings no matter what the purpose or size. These features do not require significant research, design, or capital costs and yet they can reduce Operation and Maintenance (O&M) costs and produce more environmentally friendly buildings. LEED Certification features are more aggressive than the Baseline Minimums in that they require documentation, studies, and/or additional funding. Combined with the Baseline Minimums, many of the features in this level will need to be implemented to achieve the goal of LEED certification. LEED Silver certification should be the minimum goal for all new buildings (including office buildings, laboratories, cafeterias, and visitor centers) greater than 25,000 square feet or a total cost of $10 million. Innovative features can also contribute to LEED certification, but are less mainstream than those listed in the previous two levels. These features are identified as areas where

  14. ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

    EPA Science Inventory

    In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

  15. Facile green synthesis of functional nanoscale zero-valent iron and studies of its activity toward ultrasound-enhanced decolorization of cationic dyes.

    PubMed

    Wang, Xiangyu; Wang, Anqi; Ma, Jun; Fu, Minglai

    2017-01-01

    For the first time, an integrated green technology by coupling functional nanoscale zero-valent iron (NZVI) with ultrasound (US) was innovatively developed for the enhanced decolorization of malachite green (MG) and methylene blue (MB). The functional NZVI (TP-Fe) was successfully fabricated via a facile, one-step and environmentally-benign approach by directly introducing high pure tea polyphenol (TP), where TP contenting abundant epicatechin was employed as reductant, dispersant and capping agent. Note that neither additional extraction procedure nor protection gas was needed during the entire synthesis process. Affecting factors (including US frequency, initial pH, dye concentration, and reaction temperature) were investigated. Results show that TP-Fe exhibited enhanced activity, antioxidizability and stability over the reaction course, which could be attributed to the functionalization of TP on NZVI and the invigorating effect of US (i.e., improving the mass transfer rate, breaking up the aggregates of TP-Fe nanoparticles, and maintaining the TP-Fe surface activity). The kinetics for MG and MB decolorization by the TP-Fe/US system could be well described by a two-parameter pseudo-first-order decay model, and the activation energies of MG and MB decolorization in this new system were determined to be 21 kJ mol(-1) and 24 kJ mol(-1), respectively. In addition, according to the identified reaction products, a possible mechanism associated with MG and MB decolorization with the TP-Fe/US system was proposed.

  16. Green Chemistry Metrics with Special Reference to Green Analytical Chemistry.

    PubMed

    Tobiszewski, Marek; Marć, Mariusz; Gałuszka, Agnieszka; Namieśnik, Jacek

    2015-06-12

    The concept of green chemistry is widely recognized in chemical laboratories. To properly measure an environmental impact of chemical processes, dedicated assessment tools are required. This paper summarizes the current state of knowledge in the field of development of green chemistry and green analytical chemistry metrics. The diverse methods used for evaluation of the greenness of organic synthesis, such as eco-footprint, E-Factor, EATOS, and Eco-Scale are described. Both the well-established and recently developed green analytical chemistry metrics, including NEMI labeling and analytical Eco-scale, are presented. Additionally, this paper focuses on the possibility of the use of multivariate statistics in evaluation of environmental impact of analytical procedures. All the above metrics are compared and discussed in terms of their advantages and disadvantages. The current needs and future perspectives in green chemistry metrics are also discussed.

  17. GreenSCOR: Developing a Green Supply Chain Analytical Tool

    DTIC Science & Technology

    2003-03-01

    An emerging area in supply chain practice is green supply chain management, which integrates environmental management with traditional supply chain management...GreenSCOR is the solution to closing this gap. GreenSCOR is a modification of version 5.0 of the Supply Chain Operations Reference (SCOR...model developed by the Supply - Chain Council (SCC). LMI used SCOR as a foundation because it has been proven over several years of continual development

  18. Fishing down the largest coral reef fish species.

    PubMed

    Fenner, Douglas

    2014-07-15

    Studies on remote, uninhabited, near-pristine reefs have revealed surprisingly large populations of large reef fish. Locations such as the northwestern Hawaiian Islands, northern Marianas Islands, Line Islands, U.S. remote Pacific Islands, Cocos-Keeling Atoll and Chagos archipelago have much higher reef fish biomass than islands and reefs near people. Much of the high biomass of most remote reef fish communities lies in the largest species, such as sharks, bumphead parrots, giant trevally, and humphead wrasse. Some, such as sharks and giant trevally, are apex predators, but others such as bumphead parrots and humphead wrasse, are not. At many locations, decreases in large reef fish species have been attributed to fishing. Fishing is well known to remove the largest fish first, and a quantitative measure of vulnerability to fishing indicates that large reef fish species are much more vulnerable to fishing than small fish. The removal of large reef fish by fishing parallels the extinction of terrestrial megafauna by early humans. However large reef fish have great value for various ecological roles and for reef tourism.

  19. Fish-protection devices at unscreened water diversions can reduce entrainment: evidence from behavioural laboratory investigations

    PubMed Central

    Poletto, Jamilynn B.; Cocherell, Dennis E.; Mussen, Timothy D.; Ercan, Ali; Bandeh, Hossein; Kavvas, M. Levent; Cech, Joseph J.; Fangue, Nann A.

    2015-01-01

    Diversion (i.e. extraction) of water from rivers and estuaries can potentially affect native wildlife populations if operation is not carefully managed. For example, open, unmodified water diversions can act as a source of injury or mortality to resident or migratory fishes from entrainment and impingement, and can cause habitat degradation and fragmentation. Fish-protection devices, such as exclusion screens, louvres or sensory deterrents, can physically or behaviourally deter fish from approaching or being entrained into water diversions. However, empirical assessment of their efficacy is often lacking or is investigated only for particular economically or culturally important fishes, such as salmonids. The Southern population of anadromous green sturgeon (Acipenser medirostris) is listed as threatened in California, and there is a high density of water diversions located within their native range (the Sacramento–San Joaquin watershed). Coupled with their unique physiology and behaviour compared with many other fishes native to California, the green sturgeon is susceptible to entrainment into diversions and is an ideal species with which to study the efficacy of mitigation techniques. Therefore, we investigated juvenile green sturgeon (188–202 days post-hatch) in the presence of several fish-protection devices to assess behaviour and entrainment risk. Using a large experimental flume (∼500 kl), we found that compared with an open diversion pipe (control), the addition of a trash-rack box, louvre box, or perforated cylinder on the pipe inlet all significantly reduced the proportion of fish that were entrained through the pipe (P = 0.03, P = 0.028, and P = 0.028, respectively). Likewise, these devices decreased entrainment risk during a single movement past the pipe by between 60 and 96%. These fish-protection devices should decrease the risk of fish entrainment during water-diversion activities. PMID:27293725

  20. Fish and Fisheries Ecology.

    PubMed

    Magnuson, John J

    1991-02-01

    My paper on fish and fisheries ecology is offered to demonstrate a rich blending of applied and fundamental ecology, achieved by the intersections among fishery science, ichthyology, and ecology. The example, while specific, parallels practices and opportunities available in other areas of applied ecology. The emergence of fish and fisheries ecology as a discipline is evidence by such recent textbooks as Fisheries ecology by Pitcher and Hart (1982) and Ecology of teleost fishes by Wootton (1990). The ecology relevant to fish and fisheries includes not only marine and freshwater ecology, oceanography, and limnology, but also terrestrial study. Early work in fish and fisheries ecology came from Stephen A. Forbes > 100 yr ago in his books On some interactions of organisms (Forbes 1880) and The lake as a microcosm (Forbes 1887). These constitute one of the earliest conceptualizations of an ecosystem. By 1932 E. S. Russell concluded that fishery research was a study in marine ecology. I give examples of applications from six different categories of ecology. (1) Physiological ecology: The F. E. J. Fry school of fish physiology developed the concepts of temperature as a lethal, controlling and directive factor. More than 40 yr later, this knowledge is being combined with G. E. Hutchinson's concept of an n-dimensional niche to analyze potential influences of global climate warming on fishes. (2) Behavioral ecology: A. D. Hasler and students formulated and tested the hypothesis of olfactory imprinting as the mechanism by which Pacific salmon "home" to their natal spawning streams. Applications to reestablish salmon runs are as important to Hasler as the original scientific discovery; this is evident in his proposed "Salmon for Peace" for the river bounding USSR and China. (3) Population ecology: The realization that reproductive success of fishes depends more on larval mortality than on egg production emerged from the ideas of J. Hjort (1914). To this day inconsistencies

  1. Cowlitz Falls Fish Passage.

    SciTech Connect

    1995-09-01

    The upper Cowlitz was once home to native salmon and steelhead. But the combined impacts of overharvest, farming, logging and road building hammered fish runs. And in the 1960s, a pair of hydroelectric dams blocked the migration path of ocean-returning and ocean-going fish. The lower Cowlitz still supports hatchery runs of chinook, coho and steelhead. But some 200 river miles in the upper river basin--much of it prime spawning and rearing habitat--have been virtually cut off from the ocean for over 26 years. Now the idea is to trap-and-haul salmon and steelhead both ways and bypass previously impassable obstacles in the path of anadromous fish. The plan can be summarized, for the sake of explanation, in three steps: (1) trap and haul adult fish--collect ocean-returning adult fish at the lowermost Cowlitz dam, and truck them upstream; (2) reseed--release the ripe adults above the uppermost dam, and let them spawn naturally, at the same time, supplement these runs with hatchery born fry that are reared and imprinted in ponds and net pens in the watershed; (3) trap and haul smolts--collection the new generation of young fish as they arrive at the uppermost Cowlitz dam, truck them past the three dams, and release them to continue their downstream migration to the sea. The critical part of any fish-collection system is the method of fish attraction. Scientists have to find the best combination of attraction system and screens that will guide young fish to the right spot, away from the turbine intakes. In the spring of 1994 a test was made of a prototype system of baffles and slots on the upriver face of the Cowlitz Falls Dam. The prototype worked at 90% efficiency in early tests, and it worked without the kind of expensive screening devices that have been installed on other dams. Now that the success of the attraction system has been verified, Harza engineers and consultants will design and build the appropriate collection part of the system.

  2. Immunity to fish rhabdoviruses

    USGS Publications Warehouse

    Purcell, Maureen K.; Laing, Kerry J.; Winton, James R.

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non-virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  3. Fish robotics and hydrodynamics

    NASA Astrophysics Data System (ADS)

    Lauder, George

    2010-11-01

    Studying the fluid dynamics of locomotion in freely-swimming fishes is challenging due to difficulties in controlling fish behavior. To provide better control over fish-like propulsive systems we have constructed a variety of fish-like robotic test platforms that range from highly biomimetic models of fins, to simple physical models of body movements during aquatic locomotion. First, we have constructed a series of biorobotic models of fish pectoral fins with 5 fin rays that allow detailed study of fin motion, forces, and fluid dynamics associated with fin-based locomotion. We find that by tuning fin ray stiffness and the imposed motion program we can produce thrust both on the fin outstroke and instroke. Second, we are using a robotic flapping foil system to study the self-propulsion of flexible plastic foils of varying stiffness, length, and trailing edge shape as a means of investigating the fluid dynamic effect of simple changes in the properties of undulating bodies moving through water. We find unexpected non-linear stiffness-dependent effects of changing foil length on self-propelled speed, and as well as significant effects of trailing edge shape on foil swimming speed.

  4. Greening critical care

    PubMed Central

    2011-01-01

    Climate change and environmental stewardship are phrases that have been defining the past few decades and promoting change in our societies. The sensitivities of intensive care as a specialty make the process of greening an intensive care unit a challenge, but not one that is insurmountable. This paper discusses opportunities for critical care to reduce its environmental impact and provide a framework change. The article includes suggestions of what can be done as an individual, as a unit and as a hospital. Generally, practices in critical care are accepted without questioning the environmental consequences. We believe it is time for change, and critical care should give environmental stewardship a higher priority. PMID:21635700

  5. Can Fish Catch On in Your Class?

    ERIC Educational Resources Information Center

    Butzow, John W.; Kane, Philip N.

    1983-01-01

    Presented are several classroom activities using fish. These include gyotaku (Japanese fish printing), use of a dichotomous key to classify fish, "invent-a-fish" activities, and others. Includes discussion of fish facts and copies of fish key and invent-a-fish cards. (JN)

  6. Green chemistry: principles and practice.

    PubMed

    Anastas, Paul; Eghbali, Nicolas

    2010-01-01

    Green Chemistry is a relatively new emerging field that strives to work at the molecular level to achieve sustainability. The field has received widespread interest in the past decade due to its ability to harness chemical innovation to meet environmental and economic goals simultaneously. Green Chemistry has a framework of a cohesive set of Twelve Principles, which have been systematically surveyed in this critical review. This article covers the concepts of design and the scientific philosophy of Green Chemistry with a set of illustrative examples. Future trends in Green Chemistry are discussed with the challenge of using the Principles as a cohesive design system (93 references).

  7. Green light in photomorphogenic development

    NASA Astrophysics Data System (ADS)

    Maruhnich, Stefanie Anne

    Light quality, quantity, and duration provide essential environmental cues that shape plant growth and development. Over the last century, researchers have worked to discover how plants sense, integrate, and respond to red, blue, and far-red light. Green light is often considered a “benign” wavelength with little to no effect in plant development. However, sparse experiments in the literature demonstrate that green effects are often counterintuitive to normal light responses and oppose red- and blue-light-induced responses. Green light effects on plant growth and development are described here through the use of custom, tunable LED, light-emitting diode, chambers. These light sources allow for specific light qualities and quantities to be administered. The effects of green wavebands were assessed when red and blue photomorphogenic systems were active to answer the question: Are the effects of an inhibitor (green light) more evident in the presence of inducers (red and blue light)? In seedlings, supplemental green light increased hypocotyl elongation opposite to classical inhibition of hypocotyl elongation associated with growth in light and induced by red and blue wavebands. Results indicate that added green light induced a reversion of light-grown phenotypes. In mature plants, supplemental green light induced phenotypes typical of the shade-avoidance syndrome, including elongated petioles, smaller leaf areas, and leaf hyponasty. These responses are typical of lower-light conditions or far-red enriched environments. Contrary to far-red-light-induced shade-avoidance, data indicate green delays flowering. In Arabidopsis and strawberry plants, anthocyanin levels also decreased when green light was added to red and blue light treatments, which is again opposite to normal light-induced phenotypes. Photoreceptor mutants were tested and indicate green light effects in early development are cryptochromedependent. However, green-light-induced shade-avoidance responses

  8. Dynamite fishing in Tanzania.

    PubMed

    Slade, Lorna M; Kalangahe, Baraka

    2015-12-30

    Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private-public partnerships for patrol and protection.

  9. [Ciguatera fish poisoning].

    PubMed

    Oehler, Erwan; Bouchut, Jérémie

    2014-09-01

    Ciguatera, an ichtyosarcotoxism linked to the consumption of usually healthy coral fish is a common poisoning in the Pacific, Caribbean and Indian Ocean where it is endemic. However, increased tourism and commercial transportation of tropical fish for consumption make it an unexceptional intoxication in countries away from its endemic area. Environmental stresses such as climate changes also contribute to the expansion of its geographical area. The non-specific clinical symptomatology is characterized by the occurrence of gastrointestinal, cardiovascular, nervous and general signs few hours after eating a ciguatoxic fish. The diagnosis is clinical and relatively easy in endemic areas but much less for physicians who are rarely confronted with, which is a source of prolonged diagnostic delays and a significant increase in spending. Treatment of ciguatera is symptomatic but new treatments, still experimental, give a real hope for the future.

  10. CO-FISH, COD-FISH, ReD-FISH, SKY-FISH.

    PubMed

    Williams, Eli S; Cornforth, Michael N; Goodwin, Edwin H; Bailey, Susan M

    2011-01-01

    Fluorescence in situ hybridization (FISH) has become a powerful tool for exploring genomes at the level of chromosomes. The procedure can be used to identify individual chromosomes, rearrangements between chromosomes, and the location within a chromosome of specific DNA sequences such as centromeres, telomeres, and even individual genes. Chromosome orientation FISH (CO-FISH) extends the information obtainable from standard FISH to include the relative orientation of two or more DNA sequences within a chromosome (Goodwin and Meyne, Cytogenet Cell Genet 63:126-127, 1993). In combination with a suitable reference probe, CO-FISH can also determine the absolute 5'-3' direction of a DNA sequence relative to the short arm (pter) to long arm (qter) axis of the chromosome. This variation of CO-FISH was originally termed "COD-FISH" (Chromosome orientation and direction FISH) to reflect this fact (Meyne and Goodwin, Chromosome Research 3:375-378, 1995). Telomeric DNA serves as a convenient and absolute reference probe for this purpose, since all G-rich 5'-(TTAGGG)( n )-3' telomeric sequences are terminally located and oriented away from the centromere.In the beginning, CO-FISH was used to detect obligate chromosomal inversions associated with isochromosome formation (Bailey et al., Mutagenesis 11:139-144, 1996), various pericentric inversions (Bailey et al., Cytogenetics and Cell Genetics 75:248-253, 1996), and to confirm the origin of centromeric lateral asymmetry (Goodwin et al., Chromosoma 104:345-347, 1996). More recent and sophisticated applications of CO-FISH include distinction between telomeres produced via leading- vs. lagging-strand DNA synthesis (Bailey et al., Science 293:2462-2465, 2001), identification of interstitial blocks of telomere sequence that result from inappropriate fusion to double-strand breaks (telomere-DSB fusion) (Bailey et al., DNA Repair (Amst) 3:349-357, 2004), discovery of elevated rates of mitotic recombination at chromosomal termini

  11. Can Growth Be Green?

    PubMed

    Gough, Ian

    2015-01-01

    This short article, based on a presentation at the London School of Economics, criticizes the common opinion that "green growth" offers a relatively painless - some even say pain-free - transition path for capitalist economies. After a brief summary of the daunting arithmetic entailed in combining fast decarbonization with continuing growth, the article advances 3 propositions. First, market-based carbon mitigation programs, such as carbon trading, cannot be sufficient and must be coupled with other policy pillars that foster transformative investment and widespread regulation. Second, a political economy of climate policy needs to draw on the lessons of comparative social policy research, which emphasizes the role of international pressures, interests, institutions, and ideas. Taking these into account gives a more realistic perspective on climate policy making in today's neoliberal world. Third, more radical policies on both consumption and production are called for, to ensure that carbon mitigation is not pursued at the expense of equity and social welfare. These include policies to restrain high-carbon luxury consumption and a transition toward shorter paid working time. The conclusion is that a realistic program of green growth will be immensely difficult and entail radical political change.

  12. The Green Bank Telescope

    NASA Astrophysics Data System (ADS)

    Jewell, P. R.

    1999-12-01

    The Green Bank Telescope The 100-m NRAO Green Bank Telescope will be completed in early 2000. The GBT has a large number of unique design and performance features that will give it unprecedented scientific capability. This poster display will review those features, which include an offset feed (clear aperture) design, an active surface, a closed-loop laser metrology system for surface figure and pointing control, broad frequency coverage from 100 MHz to 115 GHz, a versatile receiver selection mechanism, and a new multi-input, 256k-channel autocorrelation spectrometer. The status of the project, the commissioning schedule, plans for early operations, the initial instrumentation suite, and plans for future instrumentation will be reviewed. Scientific areas for which the GBT will have a large impact will be discussed, including observations of young galaxies at extreme redshifts, pulsars, HI and molecular spectroscopy, VLBI work, and millimeter-wave spectroscopy and continuum studies. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  13. Greening of orthopedic surgery.

    PubMed

    Lee, Rushyuan J; Mears, Simon C

    2012-06-01

    Every year, 4 billion pounds of waste are produced by health care facilities, and the amount continues to increase annually. In response, a movement toward greening health care has been building, with a particular focus on the operating room. Between 20% and 70% of health care waste originates from a hospital's operating room, and up to 90% of operating room waste is improperly sorted and sent for costly and unneeded hazardous waste processing. Recent successful changes include segregation of hospital waste, substitution of the ubiquitous polypropylene plastic wrap used for the sterilization and handling of surgical equipment with metal cases, and the reintroduction of reusable surgical gowns. Orthopedic-related changes include the successful reprocessing and reuse of external fixators, shavers, blades, burs, and tourniquets. These changes have been shown to be environmentally and economically beneficial. Early review indicates that these changes are feasible, but a need exists for further evaluation of the effect on the operating room and flow of the surgical procedure and of the risks to the surgeons and operating room staff. Other key considerations are the effects of reprocessed and reused equipment on patient care and outcome and the role of surgeons in helping patients make informed decisions regarding surgical care. The goals of this study were to summarize the amount and types of waste produced in hospitals and operating rooms, highlight the methods of disposal used, review disposal methods that have been developed to reduce waste and improve recycling, and explore future developments in greening health care.

  14. 77 FR 2296 - Office of Federal High-Performance Green Buildings; the Green Building Advisory Committee...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... ADMINISTRATION Office of Federal High-Performance Green Buildings; the Green Building Advisory Committee... provides the schedule for three teleconference meetings of the Green Building Advisory Committee (the..., Designated Federal Officer, Office of Federal High Performance Green Buildings, Office of...

  15. Investigating Green: Creating Surveys to Answer Questions

    ERIC Educational Resources Information Center

    Farenga, Stephen; Joyce, Beverly A.; Ness, Daniel

    2010-01-01

    Being green means different things to different people. Some suggest that being green means saving energy, not wasting paper towels, going solar, harnessing wind, using less fertilizer, or buying products that are organically grown. Given that being green can mean a lot of things, what does "being green" or "going green" mean to both you and your…

  16. Green(ing) English: Voices Howling in the Wilderness?

    ERIC Educational Resources Information Center

    Bruce, Heather E.

    2011-01-01

    The relatively new fields of ecocriticism in literary studies and ecocomposition in rhetoric and composition studies provide a usable foundation for those interested in green(ing) English. Nevertheless, even suggesting that interest in the environment within English studies is a relatively new concern is somewhat misleading. Contemplation of…

  17. Interior below decks in fish hold looking forward. Fish hatch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior below decks in fish hold looking forward. Fish hatch opening is at upper left, ceiling planks and knees at center and right. - Purse Seiner SHENANDOAH, Gig Harbor Peninsula Historical Society and Museum, Gig Harbor, Pierce County, WA

  18. 49 CFR 173.218 - Fish meal or fish scrap.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized for...) Polyethylene-lined burlap or paper bag; (4) Cargo tank; (5) Portable tank; (6) Rail car; or (7)...

  19. 49 CFR 173.218 - Fish meal or fish scrap.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized for...) Polyethylene-lined burlap or paper bag; (4) Cargo tank; (5) Portable tank; (6) Rail car; or (7)...

  20. 49 CFR 173.218 - Fish meal or fish scrap.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized for transportation by vessel only when packaged as follows: (1) Burlap (jute) bag; (2) Multi-wall paper bag;...