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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469307

RESUMO

Abstract Indian major carps are the widely consumed fish species of Pakistan, being a cheap source of proteins and unsaturated fatty acids, they are good for cardiovascular health. Water pollution due to discharge of untreated industrial waste water into water bodies contaminates this precious source of nutrients. The present study therefore, was aimed to assess deterioration of fatty acid profile of three Indian major carp species due to different concentrations of industrial wastes. The water samples were collected from the river Chenab at the site where it receives industrial wastewater via Chakbandi drain. After exposure to 1.5%, 3.0%, and 4.5% dilutions of collected water in different aquaria it was observed that proportion of unsaturated fatty acids in selected fish species were decreased significantly as the intensity of the dose increased (P 0.05). Conversely the level of saturated fatty acids increased with the increasing dose of treatment (P 0.05). These findings suggest that untreated wastewater not only deteriorate the fatty acid profile of aquatic animals but also these toxic substances can reach human body through fish meat and pose further health hazards. Therefore, it is highly recommended that industrial effluents should be treated before they are dumped into water bodies.


Resumo As carpas indianas são as espécies de peixes mais consumidas no Paquistão, sendo uma fonte barata de proteínas e de ácidos graxos insaturados e boa para a saúde cardiovascular. A poluição da água por causa do descarte de resíduos industriais não tratados em corpos dágua contamina essa preciosa fonte de nutrientes. Portanto, o presente estudo teve como objetivo avaliar a deterioração do perfil de ácidos graxos de três principais espécies de carpas indianas em diferentes concentrações de resíduos industriais. As amostras de água foram coletadas do rio Chenab no local onde recebe esgoto industrial via dreno de Chakbandi. Após a exposição a diluições de 1,5%, 3% e 4,5% da água coletada em diferentes aquários, foi observado que a proporção de ácidos graxos insaturados em espécies de peixes selecionadas diminuiu significativamente com o aumento da intensidade da dose (P 0,05). Por outro lado, o nível de ácidos graxos saturados aumentou com a elevação da dose de tratamento (P 0,05). Essas descobertas sugerem que águas residuais não tratadas não apenas deterioram o perfil de ácidos graxos dos animais aquáticos, mas também essas substâncias tóxicas podem atingir o corpo humano por meio da carne de peixe e representar mais riscos à saúde. Portanto, é recomendável que os efluentes industriais sejam tratados antes de serem despejados em corpos dágua.

2.
Braz. j. biol ; 84: e254252, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355876

RESUMO

Abstract Indian major carps are the widely consumed fish species of Pakistan, being a cheap source of proteins and unsaturated fatty acids, they are good for cardiovascular health. Water pollution due to discharge of untreated industrial waste water into water bodies contaminates this precious source of nutrients. The present study therefore, was aimed to assess deterioration of fatty acid profile of three Indian major carp species due to different concentrations of industrial wastes. The water samples were collected from the river Chenab at the site where it receives industrial wastewater via Chakbandi drain. After exposure to 1.5%, 3.0%, and 4.5% dilutions of collected water in different aquaria it was observed that proportion of unsaturated fatty acids in selected fish species were decreased significantly as the intensity of the dose increased (P < 0.05). Conversely the level of saturated fatty acids increased with the increasing dose of treatment (P < 0.05). These findings suggest that untreated wastewater not only deteriorate the fatty acid profile of aquatic animals but also these toxic substances can reach human body through fish meat and pose further health hazards. Therefore, it is highly recommended that industrial effluents should be treated before they are dumped into water bodies.


Resumo As carpas indianas são as espécies de peixes mais consumidas no Paquistão, sendo uma fonte barata de proteínas e de ácidos graxos insaturados e boa para a saúde cardiovascular. A poluição da água por causa do descarte de resíduos industriais não tratados em corpos d'água contamina essa preciosa fonte de nutrientes. Portanto, o presente estudo teve como objetivo avaliar a deterioração do perfil de ácidos graxos de três principais espécies de carpas indianas em diferentes concentrações de resíduos industriais. As amostras de água foram coletadas do rio Chenab no local onde recebe esgoto industrial via dreno de Chakbandi. Após a exposição a diluições de 1,5%, 3% e 4,5% da água coletada em diferentes aquários, foi observado que a proporção de ácidos graxos insaturados em espécies de peixes selecionadas diminuiu significativamente com o aumento da intensidade da dose (P < 0,05). Por outro lado, o nível de ácidos graxos saturados aumentou com a elevação da dose de tratamento (P < 0,05). Essas descobertas sugerem que águas residuais não tratadas não apenas deterioram o perfil de ácidos graxos dos animais aquáticos, mas também essas substâncias tóxicas podem atingir o corpo humano por meio da carne de peixe e representar mais riscos à saúde. Portanto, é recomendável que os efluentes industriais sejam tratados antes de serem despejados em corpos d'água.


Assuntos
Humanos , Animais , Poluentes Químicos da Água/análise , Carpas , Indústria Têxtil , Rios , Ácidos Graxos
3.
Environ Sci Pollut Res Int ; 30(13): 36244-36258, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36547835

RESUMO

In this study, we evaluated, in a pioneering way, the influence of wavelengths from the decomposition of white light on the production and physicochemical properties of silver nanoparticles (AgNPs). Bearing in mind a process of green synthesis, an extract of the bracts of Bougainvillea glabra Choisy (BgC) was used, a species native to tropical and subtropical regions and frequently used in ornamentation, possessing in its photochemical composition, biomolecules capable of acting as reducing agents for convert Ag+ to Ag0. We used light-emitting diodes (LED) to obtain the desired wavelengths (violet, blue, green, yellow, orange, and red) in the test called rainbow, and we evaluated the obtaining of AgNPs compared to white LED light, nature, and absence of light. In the rainbow assay, we obtained a gradual increase in the intensity of the plasmonic band resonance from the red wavelength (0.124 ± 0.067 a.u.) to violet (0.680 ± 0.199 a.u.), indicating a higher reaction yield in obtaining AgNPs. Smaller hydrodynamic sizes (approximately 150 nm) at more energetic wavelengths (violet, blue, and green) about less energetic wavelengths (yellow, orange, and red) (approximately 400 nm) were obtained. Analysis by SEM microscopy, FTIR spectroscopy, and X-ray diffraction indicates the presence of silver nanoparticles in all LED colors used together with white LED light and Laboratory light (natural light). Due to the high environmental demand to remove pollutants from water sources, including textile dyes, we applied AgNPs/BgC to remove methylene blue (MB) dye from an aqueous solution. A minimum removal percentage greater than 65%, with emphasis on formulations synthesized by the colors of violet LED (84.27 ± 2.65%) and orange LED (85.91 ± 1.95%), was obtained.


Assuntos
Nanopartículas Metálicas , Azul de Metileno , Azul de Metileno/química , Prata/química , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Extratos Vegetais/química , Química Verde/métodos , Difração de Raios X
4.
Braz J Microbiol ; 52(4): 1755-1767, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34494227

RESUMO

Stenotrophomonas' metabolic versatility plays important roles in the remediation of contaminated environment and plant growth promotion. We investigated two Stenotrophomonas strains isolated from textile polluted sewage for their ability to decolorize and degrade azo dyes. Two Stenotrophomonas strains (TepeL and TepeS) were isolated from textile effluents (Tepetitla, Mexico) using the selective agar Stenotrophomonas vancomycin, imipenem, amphotericin B agar (SVIA). Isolates' identity was determined by the sequencing of their partial 16S rRNA fragments. Their abilities to decolorize dyes were tested in a Luria broth supplemented with varying concentrations (50 mg/L-1 g/L) of textile dyes (acidic red, methyl orange, reactive green, acidic yellow, and reactive black). Fourier-transform infrared (FTIR) spectroscopy and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) metabolite analyses were used to determine the effect of the isolates' growth on the dyes (acidic red, methyl orange). We also identified the enzymes that may be involved in the degradation process. Phylogenetic analysis based on the 16S rDNA sequences showed that the isolates belong to the genus Stenotrophomonas. Stenotrophomonas sp. TepeL and TepeS respectively decolorize all the azo dyes at the tested concentration except at 1 g/L and degraded the azo dyes. The degradation resulted in the formation of N, N-dimethyl p-phenylenediamine, and sodium 4-amino-1-naphthalenesulfonate from methyl orange and acid red. TepeL and TepeS rapidly decolorized and degraded the azo dyes tested. This result showed that the two isolates have a good potential for the decontamination of textile effluents.


Assuntos
Compostos Azo , Biodegradação Ambiental , Stenotrophomonas , Têxteis , Ágar , Compostos Azo/metabolismo , Cromatografia Líquida , Corantes/metabolismo , México , Filogenia , RNA Ribossômico 16S/genética , Stenotrophomonas/genética , Stenotrophomonas/metabolismo , Espectrometria de Massas em Tandem , Águas Residuárias/química , Águas Residuárias/microbiologia
5.
Environ Sci Pollut Res Int ; 28(44): 63202-63214, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34224093

RESUMO

Textile dyeing consumes high volumes of water, generating proportional number of colored effluents which contain several hazardous chemical. These contaminants can implicate in significant changes in aquatic environmental, including several adverse effects to organisms in different trophic levels. The present study was developed to assess the ecotoxicological effects of textile effluent samples and reactive Red 239 dye (used in cotton dyeing) to aquatic organisms Vibrio fischeri bacteria, Daphnia similis crustacean, and Biomphalaria glabrata snail (adults and embryos). Chronic assays with lethal and sublethal effects for Daphnia similis were included and performed only for textile effluents samples. The mutagenicity was also evaluated with Salmonella/microsome assay (TA98, TA100, and YG1041 strains). V. fischeri bacteria was the most sensitive to reactive Red 239 dye (EC50 = 10.14 mg L-1) followed by mollusk embryos at all stages (EC50 = 116.41 to 124.14 mg L-1), D. similis (EC50= 389.42 mg L-1), and less sensitive to adult snails (LC50= 517.19 mg L-1). The textile effluent was toxic for all exposed organisms [E(L)C50 < 15%] and B. glabrata embryos showed different responses in the early stages of blastulae and gastrulae (EC50 = 7.60 and 7.08%) compared to advanced development stages trochophore and veliger (EC50 = 21.56 and 29.32%). Developmental and sublethal effects in B. glabrata embryos and D. similis were evidenced. In the chronic assay with effluent, the EC10/NOEC = 3% was obtained. Mutagenic effects were not detected for dye aqueous solutions neither for effluents samples. These data confirmed the importance of evaluating the effects in aquatic organisms from different trophic levels and reinforce the need for environmental aquatic protection.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água , Animais , Corantes/toxicidade , Daphnia , Têxteis , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
Braz. J. Biol. ; 81(2): 398-405, Mar.-May 2021. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-762746

RESUMO

Continuous occurrence of heavy metals is a major cause of environmental pollution due to its toxic effects. At minimum concentrations, these metals are highly reactive and can gather in the food chains and food web, causing major dangers to public health concerns. Soil samples were collected from Paharang drain, Faisalabad. Cadmium tolerant bacteria were isolated and evaluated for their MIC against Cd. The isolated bacterial strain GCFSD01 showed MIC value upto 30 mM/L. The bacterial strain with the highest resistance against Cd was selected for further study. Molecular characterization of bacterial isolate GCFSD01 was performed by 16S rRNA which confirmed it as Bacillus cereus. Optimum growth conditions of bacterial strain were also evaluated. Strain GCFSD01 showed optimum growth at pH 7 and 37 °C temperature. Our result revealed that B. cereus strain GCFSD01 reduced 61.3% Cd after 48 hrs. Multiple metal tolerance and Cd reduction by B. cereus indicate its potential for further use for decontamination of polluted soil.(AU)


A ocorrência contínua de metais pesados é uma das principais causas de poluição ambiental devido aos seus efeitos tóxicos. A contaminação por metais pesados representa um grande risco para todas as formas de vida encontradas no meio ambiente. Em concentrações mínimas, esses metais são altamente reativos e podem se acumular nas cadeias alimentares e na cadeia alimentar, causando grandes perigos às preocupações com a saúde pública. Amostras de solo foram coletadas no esgoto de Paharang, Faisalabad. Bactérias tolerantes ao cádmio foram isoladas da amostra coletada pelo método da placa de ágar. As colônias separadas individuais selecionadas foram avaliadas quanto às suas concentrações inibitórias mínimas contra Cd. A cepa bacteriana isolada GCFSD01 apresentou valores de CIM de 30 mM/L. A colônia bacteriana que apresentou maior resistência contra o Cd foi selecionada para identificação. Após seleção da maior colônia bacteriana resistente ao Cd, coloração de Gram e diferentes testes bioquímicos foram realizados para a caracterização da bactéria isolada. A caracterização molecular do isolado bacteriano GCFSD01 foi realizada por PCR 16S rRNA confirmando a presença de Bacillus cereus. Após a identificação molecular, as condições ótimas de crescimento da cepa bacteriana também foram verificadas. A cepa GCFSD01 apresentou crescimento ótimo em pH 7 e temperatura de 37 °C. Nosso resultado revelou que a cepa de B. cereus GCFSD01 reduziu 61,3% de Cd após 48 horas. A tolerância a múltiplos metais e a redução de Cd por B. cereus indicam seu potencial para uso posterior na descontaminação do solo poluído.(AU)


Assuntos
Bacillus cereus/efeitos dos fármacos , Bacillus cereus/isolamento & purificação , Intoxicação por Cádmio , Análise do Solo
7.
Environ Sci Pollut Res Int ; 28(21): 27318-27332, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33511534

RESUMO

Fabric dyeing produces high amounts of wastewater containing organic and inorganic pollutants such as reactive dyes that are the most common textile dyes employed by the industry. Three vinylsulfonic reactive dyes, blue 19 (B-19), red 198 (R-198), and yellow 15 (Y-15), were removed from effluents of industrial-like dyeing processes employing three adsorbents: (1) magnetite nanoparticles (MNP), (2) yeast waste obtained after ß-glucan removal from yeast biomass (YW), and (3) nanomagnetic composite produced from YW and MNP (YW-MNP). The non-linear kinetic pseudo-second-order and two-stage models best explained the experimental phenomena for the majority of adsorbate:adsorbent systems. The theoretical isotherm models were fitted to experimental isotherms obtained from experiments conducted with appropriated dilutions of effluents, which have a specific condition, limited by the maximum dye concentration established by the dye recipe. Thus, the saturation of adsorbents was not reached for all adsorbate:adsorbent systems. In this way, the best conditional sorption capacities (SCcond) were obtained by YW (1.7, 2.3, and 2.5 g/kg for B-19, R-198, and Y-15, respectively). The SIPS model best described all dyes adsorbed by YW, while the D-R model best described the phenomena for MNP and YW-MNP.


Assuntos
Indústria Têxtil , Poluentes Químicos da Água , Adsorção , Biomassa , Corantes , Concentração de Íons de Hidrogênio , Cinética , Saccharomyces cerevisiae , Têxteis , Termodinâmica , Poluentes Químicos da Água/análise
8.
Braz. j. biol ; 81(2): 398-405, 2021. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153348

RESUMO

Continuous occurrence of heavy metals is a major cause of environmental pollution due to its toxic effects. At minimum concentrations, these metals are highly reactive and can gather in the food chains and food web, causing major dangers to public health concerns. Soil samples were collected from Paharang drain, Faisalabad. Cadmium tolerant bacteria were isolated and evaluated for their MIC against Cd. The isolated bacterial strain GCFSD01 showed MIC value upto 30 mM/L. The bacterial strain with the highest resistance against Cd was selected for further study. Molecular characterization of bacterial isolate GCFSD01 was performed by 16S rRNA which confirmed it as Bacillus cereus. Optimum growth conditions of bacterial strain were also evaluated. Strain GCFSD01 showed optimum growth at pH 7 and 37 °C temperature. Our result revealed that B. cereus strain GCFSD01 reduced 61.3% Cd after 48 hrs. Multiple metal tolerance and Cd reduction by B. cereus indicate its potential for further use for decontamination of polluted soil.


A ocorrência contínua de metais pesados é uma das principais causas de poluição ambiental devido aos seus efeitos tóxicos. A contaminação por metais pesados representa um grande risco para todas as formas de vida encontradas no meio ambiente. Em concentrações mínimas, esses metais são altamente reativos e podem se acumular nas cadeias alimentares e na cadeia alimentar, causando grandes perigos às preocupações com a saúde pública. Amostras de solo foram coletadas no esgoto de Paharang, Faisalabad. Bactérias tolerantes ao cádmio foram isoladas da amostra coletada pelo método da placa de ágar. As colônias separadas individuais selecionadas foram avaliadas quanto às suas concentrações inibitórias mínimas contra Cd. A cepa bacteriana isolada GCFSD01 apresentou valores de CIM de 30 mM/L. A colônia bacteriana que apresentou maior resistência contra o Cd foi selecionada para identificação. Após seleção da maior colônia bacteriana resistente ao Cd, coloração de Gram e diferentes testes bioquímicos foram realizados para a caracterização da bactéria isolada. A caracterização molecular do isolado bacteriano GCFSD01 foi realizada por PCR 16S rRNA confirmando a presença de Bacillus cereus. Após a identificação molecular, as condições ótimas de crescimento da cepa bacteriana também foram verificadas. A cepa GCFSD01 apresentou crescimento ótimo em pH 7 e temperatura de 37 °C. Nosso resultado revelou que a cepa de B. cereus GCFSD01 reduziu 61,3% de Cd após 48 horas. A tolerância a múltiplos metais e a redução de Cd por B. cereus indicam seu potencial para uso posterior na descontaminação do solo poluído.


Assuntos
Poluentes do Solo/toxicidade , Bacillus cereus/genética , Cádmio/toxicidade , Efluentes Industriais/efeitos adversos , Metais Pesados/análise , Solo , Microbiologia do Solo , Biodegradação Ambiental , RNA Ribossômico 16S/genética
9.
Environ Sci Pollut Res Int, v. 28, p. 63202–63214, nov. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3889

RESUMO

Textile dyeing consumes high volumes of water, generating proportional number of colored effluents which contain several hazardous chemical. These contaminants can implicate in significant changes in aquatic environmental, including several adverse effects to organisms in different trophic levels. The present study was developed to assess the ecotoxicological effects of textile effluent samples and reactive Red 239 dye (used in cotton dyeing) to aquatic organisms Vibrio fischeri bacteria, Daphnia similis crustacean, and Biomphalaria glabrata snail (adults and embryos). Chronic assays with lethal and sublethal effects for Daphnia similis were included and performed only for textile effluents samples. The mutagenicity was also evaluated with Salmonella/microsome assay (TA98, TA100, and YG1041 strains). V. fischeri bacteria was the most sensitive to reactive Red 239 dye (EC50 = 10.14 mg L−1) followed by mollusk embryos at all stages (EC50 = 116.41 to 124.14 mg L−1), D. similis (EC50= 389.42 mg L−1), and less sensitive to adult snails (LC50= 517.19 mg L−1). The textile effluent was toxic for all exposed organisms [E(L)C50 < 15%] and B. glabrata embryos showed different responses in the early stages of blastulae and gastrulae (EC50 = 7.60 and 7.08%) compared to advanced development stages trochophore and veliger (EC50 = 21.56 and 29.32%). Developmental and sublethal effects in B. glabrata embryos and D. similis were evidenced. In the chronic assay with effluent, the EC10/NOEC = 3% was obtained. Mutagenic effects were not detected for dye aqueous solutions neither for effluents samples. These data confirmed the importance of evaluating the effects in aquatic organisms from different trophic levels and reinforce the need for environmental aquatic protection.

10.
Artigo em Inglês | VETINDEX | ID: vti-746049

RESUMO

Abstract Continuous occurrence of heavy metals is a major cause of environmental pollution due to its toxic effects. At minimum concentrations, these metals are highly reactive and can gather in the food chains and food web, causing major dangers to public health concerns. Soil samples were collected from Paharang drain, Faisalabad. Cadmium tolerant bacteria were isolated and evaluated for their MIC against Cd. The isolated bacterial strain GCFSD01 showed MIC value upto 30 mM/L. The bacterial strain with the highest resistance against Cd was selected for further study. Molecular characterization of bacterial isolate GCFSD01 was performed by 16S rRNA which confirmed it as Bacillus cereus. Optimum growth conditions of bacterial strain were also evaluated. Strain GCFSD01 showed optimum growth at pH 7 and 37 °C temperature. Our result revealed that B. cereus strain GCFSD01 reduced 61.3% Cd after 48 hrs. Multiple metal tolerance and Cd reduction by B. cereus indicate its potential for further use for decontamination of polluted soil.


Resumo A ocorrência contínua de metais pesados é uma das principais causas de poluição ambiental devido aos seus efeitos tóxicos. A contaminação por metais pesados representa um grande risco para todas as formas de vida encontradas no meio ambiente. Em concentrações mínimas, esses metais são altamente reativos e podem se acumular nas cadeias alimentares e na cadeia alimentar, causando grandes perigos às preocupações com a saúde pública. Amostras de solo foram coletadas no esgoto de Paharang, Faisalabad. Bactérias tolerantes ao cádmio foram isoladas da amostra coletada pelo método da placa de ágar. As colônias separadas individuais selecionadas foram avaliadas quanto às suas concentrações inibitórias mínimas contra Cd. A cepa bacteriana isolada GCFSD01 apresentou valores de CIM de 30 mM/L. A colônia bacteriana que apresentou maior resistência contra o Cd foi selecionada para identificação. Após seleção da maior colônia bacteriana resistente ao Cd, coloração de Gram e diferentes testes bioquímicos foram realizados para a caracterização da bactéria isolada. A caracterização molecular do isolado bacteriano GCFSD01 foi realizada por PCR 16S rRNA confirmando a presença de Bacillus cereus. Após a identificação molecular, as condições ótimas de crescimento da cepa bacteriana também foram verificadas. A cepa GCFSD01 apresentou crescimento ótimo em pH 7 e temperatura de 37 °C. Nosso resultado revelou que a cepa de B. cereus GCFSD01 reduziu 61,3% de Cd após 48 horas. A tolerância a múltiplos metais e a redução de Cd por B. cereus indicam seu potencial para uso posterior na descontaminação do solo poluído.

11.
Environ Sci Pollut Res Int ; 26(23): 24235-24246, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230237

RESUMO

The quaternization of chitosan molecules creates materials with high adsorptive capacity towards textile dyes, which renders them capable of rapidly removing such dyes from a solution. In this study, a novel material was synthesized in bead form to adsorb the Acid Blue 25 textile dye. The adsorption isotherms, kinetics, and thermodynamics of this new material were investigated. The beads were further characterized by FT-IR and SEM studies, as well as their rheological behavior. Bioassays with Daphnia similis analyzed the toxicity of the dye before and after treatments. The Freundlich isotherm model fitted to all the adsorption data in a pH range from 2.50 to 8.50. Kinetic studies showed that adsorption was ruled by an intraparticle diffusion process and reached equilibrium in 270 min, as 39.527 µg mg-1 of dye was sorbed to the beads. Thermodynamic studies showed that adsorption was a spontaneous and endothermic process. Thermodynamics also confirmed that the adsorption was proportionally influenced by higher temperatures. The FT-IR spectroscopy identified the adsorbate/adsorbent binding sites, thus confirming the occurrence of chemisorption. Post-treatment bioassays found a significant decrease in toxicity, obtaining just 10% of D. similis mortality after adsorption treatments. Therefore, the synthesized beads from this research can potentially be applied to the treatment of textile effluents.


Assuntos
Antraquinonas/química , Poluentes Químicos da Água/química , Adsorção , Quitosana/química , Corantes/química , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis , Termodinâmica
12.
Braz. j. biol ; Braz. j. biol;2017.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467445

RESUMO

Abstract Continuous occurrence of heavy metals is a major cause of environmental pollution due to its toxic effects. At minimum concentrations, these metals are highly reactive and can gather in the food chains and food web, causing major dangers to public health concerns. Soil samples were collected from Paharang drain, Faisalabad. Cadmium tolerant bacteria were isolated and evaluated for their MIC against Cd. The isolated bacterial strain GCFSD01 showed MIC value upto 30 mM/L. The bacterial strain with the highest resistance against Cd was selected for further study. Molecular characterization of bacterial isolate GCFSD01 was performed by 16S rRNA which confirmed it as Bacillus cereus. Optimum growth conditions of bacterial strain were also evaluated. Strain GCFSD01 showed optimum growth at pH 7 and 37 °C temperature. Our result revealed that B. cereus strain GCFSD01 reduced 61.3% Cd after 48 hrs. Multiple metal tolerance and Cd reduction by B. cereus indicate its potential for further use for decontamination of polluted soil.


Resumo A ocorrência contínua de metais pesados é uma das principais causas de poluição ambiental devido aos seus efeitos tóxicos. A contaminação por metais pesados representa um grande risco para todas as formas de vida encontradas no meio ambiente. Em concentrações mínimas, esses metais são altamente reativos e podem se acumular nas cadeias alimentares e na cadeia alimentar, causando grandes perigos às preocupações com a saúde pública. Amostras de solo foram coletadas no esgoto de Paharang, Faisalabad. Bactérias tolerantes ao cádmio foram isoladas da amostra coletada pelo método da placa de ágar. As colônias separadas individuais selecionadas foram avaliadas quanto às suas concentrações inibitórias mínimas contra Cd. A cepa bacteriana isolada GCFSD01 apresentou valores de CIM de 30 mM/L. A colônia bacteriana que apresentou maior resistência contra o Cd foi selecionada para identificação. Após seleção da maior colônia bacteriana resistente ao Cd, coloração de Gram e diferentes testes bioquímicos foram realizados para a caracterização da bactéria isolada. A caracterização molecular do isolado bacteriano GCFSD01 foi realizada por PCR 16S rRNA confirmando a presença de Bacillus cereus. Após a identificação molecular, as condições ótimas de crescimento da cepa bacteriana também foram verificadas. A cepa GCFSD01 apresentou crescimento ótimo em pH 7 e temperatura de 37 °C. Nosso resultado revelou que a cepa de B. cereus GCFSD01 reduziu 61,3% de Cd após 48 horas. A tolerância a múltiplos metais e a redução de Cd por B. cereus indicam seu potencial para uso posterior na descontaminação do solo poluído.

13.
J Environ Manage ; 183: 306-313, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27604754

RESUMO

The statistical Response Surface Methodology (RSM) is applied to investigate the effect of different parameters (current density, j, NaCl concentration, [NaCl], pH, and temperature, θ) and their interactions on the electrochemical degradation of the Acid Green (AG) 28 dye using a Ti/ß-PbO2 or Ti-Pt/ß-PbO2 anode in a filter-press reactor. LC/MS is employed to identify intermediate compounds. For both anodes, the best experimental conditions are j = 50 mA cm(-2), [NaCl] = 1.5 g L(-1), pH = 5, and θ = 25 °C. After 3 h of electrolysis, a dye solution treated under these conditions presents the following parameters: electric charge per unit volume of the electrolyzed solution required for 90% decolorization (Q(90)) of 0.34-0.37 A h L(-1), %COD removal of ∼100%, specific energy consumption of 18-20 kW h m(-3), and %TOC removal of 32-33%. No loss of the ß-PbO2 film is observed during all the experiments. The ß-PbO2 films present excellent stability for solutions with pH ≥ 5 ([Pb(2+)] < 0.5 mg L(-1)). Chloroform is the only volatile organic halo compound present in the treated solution under those optimized conditions. Hydroxylated anthraquinone derivatives, aromatic chloramines, and naphthoquinones are formed during the electrolyses. The Ti/ß-PbO2 and Ti-Pt/ß-PbO2 anodes show significantly better performance than a commercial DSA anode for the electrochemical degradation of the AG 28 dye. The Ti/ß-PbO2 anode, prepared as described in this work, is an excellent option for the treatment of textile effluents because of its low cost of fabrication and good performance.


Assuntos
Chumbo/química , Corantes Verde de Lissamina/química , Óxidos/química , Titânio/química , Eletroquímica , Eletrodos , Eletrólise , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Têxteis
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