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

Triphenylmethane dye (C52H54N4O12) is potentially a hazardous substance in edible freshwater fish at trace level: toxicity, hematology, biochemistry, antioxidants, and molecular docking evaluation study

Malachite green (C₅₂H₅₄N₄O₁₂) is a synthetic dye that is used in textile industries as a colorant and in aquaculture sectors to contain microbial damage. Aquatic contamination of malachite green (MG) has been reported globally. Fish is the highest trophic organism among aquatic inhabitants, highly sensitive to waterborne contaminants (metals, coloring agents, etc.). Toxicity of waterborne chemicals on nontarget organisms can be determined by assessing biomarkers. Assessing blood parameters and tissue antioxidants (enzymatic and nonenzymatic) is useful to evaluate MG toxicity. To initiate the MG toxicity data for freshwater fish (Cyprinus carpio), the median lethal toxicity was primarily evaluated. Then, hematological, blood biochemical (glucose, protein, and cholesterol) and tissue biochemical (amino acids, lipids), and vital tissue (gills, liver, and kidney) antioxidant capacity (CAT, LPO, GST, GR, POxy, vitamin C, and GSH) of C. carpio were analyzed under acute (LC_50-96 h) and sublethal (Treatment I-1/10^th and Treatment II-1/5^th LC_50-96 h) exposure periods (28 days). Molecular docking for MG with hemoglobin was also obtained. Biomarkers examined were affected in the MG-treated groups with respect to the control group. Significant changes (p < 0.05) were observed in hematology (Hb, RBCs, and WBCs), glucose, proteins, lipids and tissue CAT, LPO, and GST activities under acute MG exposure. In sublethal treatment groups, biomarkers studied were significant (p < 0.05) throughout the study period. The potential for MG binding to hemoglobin was tested in this study. MG is potentially a multiorgan toxicant. Literally a chemical that is harmful to the aquatic environment if safety is concerned.

DIGE Analysis of Fish Tissues

Two-dimensional difference gel electrophoresis (2D-DIGE) appears to be especially useful in quantitative approaches, allowing the co-separation of proteins of control samples and proteins of treated/disease samples on the same gel, eliminating gel-to-gel variability. The principle of 2D-DIGE is to label proteins prior to isoelectric focusing and use three spectrally resolvable fluorescent dyes, allowing the independent labeling of control and experimental samples. This procedure makes it possible to reduce the number of gels in an experiment, allowing the accurate and reproducible quantification of multiple samples. 2D-DIGE has been found to be an excellent methodical tool in several areas of fish research, including environmental pollution and toxicology, the mechanisms of development and disorders, reproduction, nutrition, evolution, and ecology.

Current perspective on veterinary drug and chemical residues in food of animal origin

The marked increase in the demand for animal protein of high quality necessitates protecting animals from infectious diseases. This requires increasing the use of veterinary therapeutics. The overuse and misuse of veterinary products can cause a risk to human health either as short-term or long-term health problems. However, the biggest problem is the emergence of resistant strains of bacteria or parasites. This is in addition to economic losses due to the discarding of polluted milk or condemnation of affected carcasses. This paper discusses three key points: possible sources of drug and chemical residues, human health problems, and the possible method of control and prevention of veterinary drug residues in animal products.

Equilibrium, Kinetics, and Thermodynamic Studies of Malachite Green Adsorption onto Fig (Ficus cartia) Leaves

The release of dyes from dying industries such as leather, paper, and textiles is an important cause of environmental pollution. In the present study, the batch adsorption measurements were carried out using stimulated aqueous solutions and the effect of operating variables such as initial malachite green concentration, amount of adsorbent, solution pH, contact time, and solution temperature, were investigated. The experimental result showed that the percentage removal decreased with an increase in initial dye concentration but increased as pH of the solution, contact time, and adsorbent dose increased. The equilibrium data were analyzed using Langmuir adsorption isotherm, Freundlich adsorption isotherm, and Tempkin isotherm models, and it was observed that the Langmuir adsorption isotherm better described the adsorption process. The monolayer adsorption capacity of activated carbon prepared from fig leaves for malachite green adsorption was found to be 51.79 mg/g at 298 K. Furthermore, the adsorption kinetics of the dye was investigated, and the rate of adsorption was found to follow the pseudo-first-order kinetic model with intraparticle diffusion as one of the rate-determining steps. The negative value of ΔG ⁰ and the positive values of ΔH ⁰ indicate the spontaneous and endothermic nature of the adsorption process, respectively. The experimental result obtained in the present study and comparison with other reported adsorbents indicate that activated carbon prepared from fig leaves could be used as a low-cost alternative adsorbent for the removal of malachite green from aqueous solution.

DIGE Analysis of Fish Tissues

Two-dimensional difference gel electrophoresis (2D-DIGE) appears to be especially useful in quantitative approaches, allowing the co-separation of proteins of control samples from proteins of treatment/disease samples on the same gel, eliminating gel-to-gel variability. The principle of 2D-DIGE is to label proteins prior to isoelectric focusing and use three spectrally resolvable fluorescent dyes, allowing the independent labeling of control and experimental samples. This procedure makes it possible to reduce the number of gels in an experiment, allowing the accurate and reproducible quantification of multiple samples. 2D-DIGE has been found to be an excellent methodical tool in several areas of fish research, including environmental pollution and toxicology, the mechanisms of development and disorders, reproduction, nutrition, evolution, and ecology.

Molecular imprinting based on phosphorescent resonance energy transfer for malachite green detection in fishes and water

Room temperature phosphorescent quantum dots combined with molecular imprinting technology for the highly selective detection of malachite green (MG) in fish and water.

Ionic liquid-based dispersive liquid-liquid microextraction combined with functionalized magnetic nanoparticle solid-phase extraction for determination of industrial dyes in water

N-butyl pyridinium bis((trifluoromethyl)sulfonyl)imide ([Hpy]NTf₂) functionalized core/shell magnetic nanoparticles (MNPs, Fe₃O₄@SiO₂@[Hpy]NTf₂)) were prepared and applied as an adsorbent for magnetic solid phase extraction (MSPE) of three commonly used industrial dyes including malachite green, crystal violet and methylene blue. Extraction solution was mixed with 100 mg extraction material of Fe₃O₄@SiO₂@[Hpy]NTf₂, and 1 mL of acetonitrile was used to elute target analytes for further extraction and purification. [Hpy]NTf₂ was used as extraction solution, and 500 μL methanol was selected as dispersive solvent in ionic liquid (IL) dispersive liquid–liquid microextraction (DLLME) method. After sonication for 5 min and centrifugation at 447 g for 10 min, 20 μL of sedimented phase was injected into HPLC-UV system. The limit of detection (LOD) and limit of quantification (LOQ) of current method were 0.03 and 0.16 μg·L⁻¹, respectively, which indicated the sensitivity was comparable or even superior to other reported methods. The relative recoveries of the target analytes ranged from 86.1% to 100.3% with relative standard deviations between 0.3% and 4.5%. The developed method has been successfully applied to determine the level of three industrial dyes in different water samples.

Plant immunity induced by COS-OGA elicitor is a cumulative process that involves salicylic acid

Plant innate immunity offers considerable opportunities for plant protection but beside flagellin and chitin, not many molecules and their receptors have been extensively characterized and very few have successfully reached the field. COS-OGA, an elicitor that combines cationic chitosan oligomers (COS) with anionic pectin oligomers (OGA), efficiently protected tomato (Solanum lycopersicum) grown in greenhouse against powdery mildew (Leveillula taurica). Leaf proteomic analysis of plants sprayed with COS-OGA showed accumulation of Pathogenesis-Related proteins (PR), especially subtilisin-like proteases. qRT-PCR confirmed upregulation of PR-proteins and salicylic acid (SA)-related genes while expression of jasmonic acid/ethylene-associated genes was not modified. SA concentration and class III peroxidase activity were increased in leaves and appeared to be a cumulative process dependent on the number of sprayings with the elicitor. These results suggest a systemic acquired resistance (SAR) mechanism of action of the COS-OGA elicitor and highlight the importance of repeated applications to ensure efficient protection against disease.

Proteomic changes in Corbicula fluminea exposed to wastewater from a psychiatric hospital

The increase use of pharmaceutical compounds in veterinary practice and human population results in the ubiquitous presence of these compounds in aquatic ecosystems. Because pharmaceuticals are highly bioactive, there is concern about their toxicological effects in aquatic organisms. Therefore, the aim of this study was to assess the effects of an effluent from a psychiatric hospital (containing a complex mixture of 25 pharmaceutical compounds from eleven therapeutic classes) on the freshwater clam Corbicula fluminea using a proteomic approach. The exposure of C. fluminea to this complex effluent containing anxiolytics, analgesics, lipid regulators, beta blockers, antidepressants, antiepileptics, antihistamines, antihypertensives, antiplatelets and antiarrhythmics induced protein changes after 1 day of exposure in clam gills and digestive gland more evident in the digestive gland. These changes included increase in the abundance of proteins associated with structural (actin and tubulin), cellular functions (calreticulin, proliferating cell nuclear antigen (PCNA), T complex protein 1 (TCP1)) and metabolism (aldehyde dehydrogenase (ALDH), alcohol dehydrogenase, 6 phosphogluconate dehydrogenase). Results from this study indicate that calreticulin, PCNA, ALDH and alcohol dehydrogenase in the digestive gland and T complex protein 1 (TCP1)) and 6 phosphogluconate dehydrogenase in the gills represent useful biomarkers for the ecotoxicological characterization of psychiatric hospital effluents in this species.

Synthesis and application of colloidal beta-cyclodextrin-decorated silver nanoparticles for rapid determination of malachite green in environmental water using surface-enhanced Raman spectroscopy

A series of AgNPs were synthesized by silver mirror reaction in the presence of CDs. Combined with SERS, a rapid method for the determination of MG was established successfully.

Toxic textile dyes accumulate in wild European eel Anguilla anguilla

Dyes are used to stain inks, paints, textile, paper, leather and household products. They are omnipresent, some are toxic and may threaten our environment, especially aquatic ecosystems. The presence of residues of sixteen dyes (triarylmethanes, xanthenes, phenothiazines and phenoxazines) and their metabolites was analyzed in muscle tissue samples of individual yellow-phased European eels (Anguilla anguilla) from 91 locations in Belgian rivers, canals and lakes sampled between 2000 and 2009 using ultra performance liquid chromatography-tandem mass spectrometry. Eel was contaminated by dyes in 77% of the sites. Malachite Green, Crystal Violet and Brilliant Green were present in 25-58% of the samples. Dye occurrence was related to the distribution of textile and dye production industries. This field study is the first large-scale survey to document the occurrence of artificial dyes in wildlife. Considering the annual amounts of dyes produced worldwide and the unintentional spillage during their use, our observations warrant additional research in other parts of the world. The presence of these highly toxic dyes in the European eel may form an additional threat to this critically endangered species. The contaminated eels should be considered as not suitable for consumption.

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

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.

Looking for protein expression signatures in European eel peripheral blood mononuclear cells after in vivo exposure to perfluorooctane sulfonate and a real world field study

The decline of European eel population can be attributed to many factors such as pollution by xenobiotics present in domestic and industrial effluents. Perfluorooctane sulfonate (PFOS) is a ubiquitous compound of a particular concern in Europe. PFOS can reach high concentrations in tissues of organisms and many toxic effects have been reported in fish. This study aimed at evaluating the toxicological effects of PFOS in European eel peripheral blood mononuclear cells (PBMCs) at the protein expression level. To identify proteins whose expression was modified by PFOS, we performed a proteomic analysis on the post-nuclear fraction of PBMCs after a chronic exposure (28 days) of yellow eels to zero, 1 or 10 μg/L PFOS. This in vivo study was completed by a proteomic field study on eels sampled in Belgian rivers presenting different PFOS pollution degrees. Proteins were separated by two-dimensional in-gel electrophoresis (2D-DIGE) to compare the post-nuclear fraction of PBMCs from the reference group with cells from fish exposed to the pollutant of interest. On the 28 spots that were significantly (p < 0.05; ANOVA followed by a Dunnett post-hoc test) affected by PFOS in the in vivo experiment, a total of 17 different proteins were identified using nano-LC ESI-MS/MS and the Peptide and Protein Prophet of Scaffold software. In the field experiment, 18 significantly (p < 0.05; ANOVA followed by Dunnett's test) affected spots conducted to the identification of 16 different proteins. Interestingly, only three proteins were found in common between in vivo and in situ experiments: plastin-2, alpha-enolase and glyceraldehyde 3-phosphate dehydrogenase. Comparing the results with a previous study, plastin-2 and alpha-enolase were also been found to be affected after in vitro exposure of PBMCs during 48 h to either 10 μg or 1 mg PFOS/L. Potential use of these proteins as biomarkers of PFOS exposure in European eel could indicate early warning signals.

An RNA aptamer-based electrochemical biosensor for sensitive detection of malachite green

A RNA aptamer-based electrochemical biosensing strategy has been developed for sensitive and selective detection of malachite green.

DNA repair activity in fish and interest in ecotoxicology: a review

The knowledge of DNA repair in a target species is of first importance as it is the primary line of defense against genotoxicants, and a better knowledge of DNA repair capacity in fish could help to interpret genotoxicity data and/or assist in the choice of target species, developmental stage and tissues to focus on, both for environmental biomonitoring studies and DNA repair testing. This review focuses in a first part on what is presently known on a mechanistic basis, about the various DNA repair systems in fish, in vivo and in established cell lines. Data on base excision repair (BER), direct reversal with O⁶-alkylguanine transferase and double strand breaks repair, although rather scarce, are being reviewed, as well as nucleotide excision repair (NER) and photoreactivation repair (PER), which are by far the most studied repair mechanisms in fish. Most of these repair mechanisms seem to be strongly species and tissue dependent; they also depend on the developmental stage of the organisms. BER is efficient in vivo, although no data has been found on in vitro models. NER activity is quite low or even inexistent depending on the studies; however this lack is partly compensated by a strong PER activity, especially in early developmental stage. In a second part, a survey of the ecotoxicological studies integrating DNA repair as a parameter responding to single or mixture of contaminant is realized. Three main approaches are being used: the measurement of DNA repair gene expression after exposure, although it has not yet been clearly established whether gene expression is indicative of repair capacity; the monitoring of DNA damage removal by following DNA repair kinetics; and the modulation of DNA repair activity following exposure in situ, in order to assess the impact of exposure history on DNA repair capacity. Since all DNA repair processes are possible targets for environmental pollutants, we can also wonder at which extent such a modulation of repair capacities in fish could be the base for the development of new biomarkers of genotoxicity. Knowing the importance of the germ cell DNA integrity in the reproductive success of aquatic organisms, the DNA repair capacity of such cells deserve to be more studied, as well as DNA repair capacities of established fish cell lines. The limited amount of available data, which shows low/slow DNA repair capacities of fish cell lines compared with mammalian cell lines, concerned mainly the NER system; thus this point merits to be explored more deeply. Additionally, since some of the DNA repair systems appear more efficient in embryo larval stages, it would be of interest to consider embryonic cell lineages more closely.

Proteomic responses of peripheral blood mononuclear cells in the European eel (Anguilla anguilla) after perfluorooctane sulfonate exposure

Since the 1980s, the stocks of European eel have been declining in most of their geographical distribution area. Many factors can be attributed to this decline such as pollution by xenobiotics like perfluorooctane sulfonate (PFOS). This study aimed at evaluating the in vitro toxicity of eel peripheral blood mononuclear cells (PBMC) exposed to PFOS. Exposure time and two concentrations were chosen to avoid cell mortality (48 h exposure at 10 μg PFOS/L and 1mg PFOS/L). After in vitro contaminations, the post-nuclear fraction was isolated and a proteomic analysis using 2D-DIGE was performed to compare PBMC from the control group with cells exposed to the pollutant. On the 158 spots that were significantly affected by PFOS exposure, a total of 48 different proteins were identified using nano-LCESI-MS/MS and the Peptide and Protein Prophet of Scaffold software. These proteins can be categorized into diverse functional classes, related to cytoskeleton, protein folding, cell signaling, proteolytic pathway and carbohydrate and energy metabolism, which provide clues on the cellular pathways mainly affected by PFOS. Some of the identified proteins are rarely found in other ecotoxicological proteomic studies and could constitute potential biomarkers of exposure to PFOS in fish.