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1.
Environ Res ; 241: 117547, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949288

RESUMO

Industrial wastewater effluents are a major source of chemicals in aquatic environments, and many of these chemicals may negatively impact aquatic life. In this study, the crustacean Daphnia magna, a common model organism in ecotoxicity studies, was exposed for 48 h to nine different industrial effluent samples from manufacturing facilities associated with the production of plastics, polymers, and coating products at a range of dilutions: 10, 25, 50, 100% (undiluted). A targeted metabolomic-based approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify polar metabolites from individual daphnids that survived the 48 h exposure. Multivariate analyses and metabolite changes revealed metabolic perturbations across all effluent samples studied, with non-monotonic responses and both up and downregulation relative to the unexposed control. Pathway analyses indicated the disruption of similar and distinct pathways, mostly connected to protein synthesis, amino acid metabolism, and antioxidant processes. Overall, we observed disruptions in Daphnia biochemistry that were similar across the effluent samples, but with unique features for each effluent sample. Additionally, non-monotonic heightened responses suggested additive and/or synergistic interactions between the chemicals within the industrial effluents. These findings demonstrate that targeted metabolomic approaches are a powerful tool for the biomonitoring of aquatic ecosystems in the context of complex mixtures, such as industrial wastewater effluents.


Assuntos
Daphnia magna , Poluentes Químicos da Água , Animais , Águas Residuárias/toxicidade , Antioxidantes/metabolismo , Polímeros , Aminoácidos/metabolismo , Cromatografia Líquida , Ecossistema , Espectrometria de Massas em Tandem , Metabolômica , Daphnia , Poluentes Químicos da Água/análise
2.
Environ Res ; 256: 119235, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810826

RESUMO

Dyes are the most ubiquitous organic pollutants in industrial effluents. They are highly toxic to both plants and animals; thus, their removal is paramount to the sustainability of ecosystem. However, they have shown resistance to photolysis and various biological, physical, and chemical wastewater remediation processes. Membrane removal technology has been vital for the filtration/separation of the dyes. In comparison to polymeric membranes, inorganic and mixed matrix (MM) membranes have shown potentials to the removal of dyes. The inorganic and MM membranes are particularly effective due to their high porosity, enhanced stability, improved permeability, higher enhanced selectivity and good stability and resistance to harsh chemical and thermal conditions. They have shown prospects in filtration/separation, adsorption, and catalytic degradation of the dyes. This review highlighted the advantages of the inorganic and MM membranes for the various removal techniques for the treatments of the dyes. Methods for the membranes production have been reviewed. Their application for the filtration/separation and adsorption have been critically analyzed. Their application as support for advanced oxidation processes such as persulfate, photo-Fenton and photocatalytic degradations have been highlighted. The mechanisms underscoring the efficiency of the processes have been cited. Lastly, comments were given on the prospects and challenges of both inorganic and MM membranes towards removal of the dyes from industrial effluents.


Assuntos
Corantes , Resíduos Industriais , Membranas Artificiais , Poluentes Químicos da Água , Corantes/química , Corantes/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Resíduos Industriais/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Filtração/métodos , Adsorção
3.
Int J Phytoremediation ; 26(9): 1474-1485, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38488053

RESUMO

Chromium (Cr) contamination of soil has substantially deteriorated soil health and has interfered with sustainable agricultural production worldwide and therefore, its remediation is inevitable. Inoculation of plant growth promoting rhizobacteria (PGPR) in association with nanotechnology has exerted broad based impacts in agriculture, and there is an urgent need to exploit their synergism in contaminated soils. Here, we investigated the effect of co-application of Cr-tolerant "Pseudomonas aeruginosa CKQ9" strain and nano zerovalent iron (nZVI) in improving the phytoremediation potential of aloe vera (Aloe barbadensis L.) under Cr contamination. Soil was contaminated by using potassium dichromate (K2Cr2O7) salt and 15 mg kg-1 contamination level in soil was maintained via spiking and exposure to Cr lasted throughout the duration of the experiment (120 days). We observed that the co-application alleviated the adverse impacts of Cr on aloe vera, and improved various plant attributes such as plant height, root area, number of leaves and gel contents by 51, 137, 67 and 49% respectively as compared to control treatment under Cr contamination. Similarly, significant boost in the activities of various antioxidants including catalase (124%), superoxide dismutase (87%), ascorbate peroxidase (36%), peroxidase (89%) and proline (34%) was pragmatic under contaminated soil conditions. In terms of soil Cr concentration and its plant uptake, co-application of P. aeruginosa and nZVI also reduced available Cr concentration in soil (50%), roots (77%) and leaves (84%), while simultaneously increasing the relative production index by 225% than un-inoculated control. Hence, integrating PGPR with nZVI can be an effective strategy for enhancing the phytoremediation potential of aloe vera.


Combined effect of PGPR and nanotechnology in the bioremediation of toxic contaminants is well reported in literature. Most of these reports comprise the use of hyperaccumulator plants for phytoextraction of heavy metals. However, phytostabilization potential of hyperaccumulators is still un-explored. Current study investigated the role of PGPR and Fe-NPs in suppressing the uptake of Cr in aloe vera, a hyperaccumulator plant.


Assuntos
Aloe , Biodegradação Ambiental , Cromo , Ferro , Pseudomonas aeruginosa , Poluentes do Solo , Cromo/metabolismo , Ferro/metabolismo , Poluentes do Solo/metabolismo , Pseudomonas aeruginosa/fisiologia
4.
Water Sci Technol ; 90(4): 1181-1197, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39215731

RESUMO

Groundwater and soil contamination by aromatic amines (AAs), used in the production of polymers, plastics, and pesticides, often results from improper waste disposal and accidental leaks. These compounds are resistant to anaerobic degradation; however, micro-aeration can enhance this process by promoting microbial interactions. In batch assays, anaerobic degradation of aniline (0.14 mM), a model AA, was tested under three micro-aeration conditions: T30, T15, and T10 (30, 15, and 10 min of micro-aeration every 2 h, respectively). Aniline degradation occurred in all conditions, producing both aerobic (catechol) and anaerobic (benzoic acid) byproducts. The main genera involved in T30 and T15 were Comamonas, Clostridium, Longilinea, Petrimonas, Phenylobacterium, Pseudoxanthomonas, and Thiobacillus. In contrast, in T10 were Pseudomonas, Delftia, Leucobacter, and Thermomonas. While T30 and T15 promoted microbial cooperation for anaerobic degradation and facultative respiration, T10 resulted in a competitive environment due to dominance and oxygen scarcity. Despite aniline degradation in 9.4 h under T10, this condition was toxic to Allium cepa seeds and exhibited cytogenotoxic effects. Therefore, T15 emerged as the optimal condition, effectively promoting anaerobic degradation without accumulating toxic byproducts. Intermittent micro-aeration emerges as a promising strategy for enhancing the anaerobic degradation of AA-contaminated effluents.


Assuntos
Compostos de Anilina , Biodegradação Ambiental , Compostos de Anilina/toxicidade , Compostos de Anilina/metabolismo , Anaerobiose , Cinética , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
5.
BMC Microbiol ; 23(1): 163, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280536

RESUMO

In the current study, fifty-eight Ingoldain fungal species assignable to forty-one genera were recovered from two water bodies receiving the treated sewage and the effluents of oils and soaps factory at Assiut Governorate (Upper Egypt), of which Anguillospora, Amniculicola, Flagellospora, and Mycocentrospora were the most prevalent genera. The most widespread identified species were Anguillospora furtive, Amniculicola longissima and Flagellospora fusarioides. Forty-three species were identified for the first time in Egypt. The most Ingoldain taxa were estimated for El-Zinnar canal, with the highest recorded taxa in winter. Whereas, the highest dominance of Ingoldian fungi was estimated for the El-Ibrahimia canal. The highest Simpson and Shannon diversity indexes were estimated for El-Zinnar canal samples recording 0.9683 and 3.741, respectively. The poorest water sites with Ingoldian fungi were those exposed directly to either treated sewage or industrial effluents, with which relatively higher values of water conductivity, cations and anions. Water temperature was the main abiotic factor driving the seasonal occurrence of Ingoldian fungi. It is interesting to isolate some Ingoldian fungal species from the stressful water sites receiving the effluents which provide valuable insights regarding their adaptation, predictive and putative role as bioindicators and their potentiality in pollutants degradation, organic decomposition, and transformation of xenobiotic compounds.


Assuntos
Fungos Mitospóricos , Esgotos , Egito , Esgotos/microbiologia , Estações do Ano , Água
6.
J Toxicol Environ Health A ; 86(19): 707-719, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37598363

RESUMO

The aim of this study was to examine the water quality of the Extrema River spring in a Brazilian Cerrado area. Three collection sites (P1 - P3) were sampled in the dry and rainy seasons, which are close to industries from different sectors. In the physicochemical analysis, a decrease in dissolved oxygen levels (<5 mg/L) and pH (< 6) at P3 was detected. An increase in heterotrophic bacteria count was recorded at all sites (> 500 colonies/ml). In ecotoxicological analyses, P2 and P3 exhibited toxicity using Vibrio fischeri (> 20%). In evaluating toxicity, the reduction in seed germination was significant utilizing Lactuca sativa at all locations and with Allium cepa only at P2; rootlet length was decreased at P3 on L. sativa and at all sites with A. cepa. In contrast, loss of membrane integrity and mitochondrial function of meristems was adversely affected at all locations using both L. sativa and A. cepa assays. Principal components analysis (PCA) approach indicated that seasonality apparently did not markedly interfere with the obtained data, but it is important to include more collection locations to be evaluated with multiple bioindicators in the spring region. Our data indicate the urgent need for more rigorous programs to monitor the discharge of effluents into water springs.


Assuntos
Biomarcadores Ambientais , Qualidade da Água , Aliivibrio fischeri , Bioensaio , Brasil
7.
Int J Phytoremediation ; 25(5): 598-608, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35815696

RESUMO

Stem powder and its active carbon of Arachis hypogaea plant are identified to have strong adsorptivity for lead ions. The bio-sorbents are characterized by conventional methods including XRD and FTIR analysis. These biomaterials are investigated for their maximum adsorption for lead ions by optimizing the extraction conditions. The maximum removal is observed in the pH range of 6-7 for both sorbents. With stem powders, the removal is 76.0% from a simulated lead solution of concentration: 20.0 mg/L with 1.5 g/L of the sorbent and at an equilibration time of 2.0 h. With the active carbon, the maximum extraction of: 86.0% is observed at pH: 6.5 with 1.0 g/L of the sorbent after an equilibration time of 1.5 h. The sorption capacities are 32.0 mg/g for stem powders, and 40.5 mg/g for active carbon. Many co-ions have marginal interference. Spent adsorbents can be recycled after regeneration. Thermodynamic investigations reveal the spontaneity and endothermic nature of adsorption. High ΔH values viz., 26.45 kJ/mole for AHSP and 46.40 kJ/mole for AHSAC, confirm the bonding of Pb2+ ions with the sorbents is either "ion-exchange" and/or a sort of "complex formation." The disorder at the solid and liquid boundary is indicated by high positive ΔS values and it is a favorable condition for good Pb2+ adsorption. On analysis of different kinetic and isotherm models, the sorption of Pb2+ ions follows Pseudo-2nd order and Langmuir models. This confirms the mono-layer adsorption of Pb2+ ions on the humongous surface of the sorbent. The adsorbents are successfully applied to treat industrial effluent samples.


In the present investigation, stem powder and its active carbon of Arachis hypogaea plant are identified to have strong adsorptivity for highly toxic lead ions. Successful methodologies are developed for the maximum extraction of lead ions from industrial wastewater at a convenient nearly neutral pH. The adsorption capacities are as high as: 32.0 mg/g for stem powders and 40.5 mg/g for active carbon. The sorbents are characterized and the sorption mechanism is investigated. The novelty of the present investigation is that highly toxic lead ions can be easily removed from polluted water by using simple bio-adsorbents by adopting convenient procedures.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/química , Pós , Arachis , Chumbo/análise , Biodegradação Ambiental , Termodinâmica , Íons/análise , Carbono , Adsorção , Cinética , Concentração de Íons de Hidrogênio
8.
Environ Sci Technol ; 56(16): 11354-11362, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35926116

RESUMO

Biochars can remove potentially toxic elements, such as inorganic mercury [Hg(II)] from contaminated waters. However, their performance in complex water matrices is rarely investigated, and the combined roles of natural organic matter (NOM) and ionic composition in the removal of Hg(II) by biochar remain unclear. Here, we investigate the influence of NOM and major ions such as chloride (Cl-), nitrate (NO3-), calcium (Ca2+), and sodium (Na+) on Hg(II) removal by a wood-based biochar (SWP700). Multiple sorption sites containing sulfur (S) were located within the porous SWP700. In the absence of NOM, Hg(II) removal was driven by these sites. Ca2+ bridging was important in enhancing removal of negatively charged Hg(II)-chloro complexes. In the presence of NOM, formation of soluble Hg-NOM complexes (as seen from speciation calculations), which have limited access to biochar pores, suppressed Hg(II) removal, but Cl- and Ca2+ could still facilitate it. The ability of Ca2+ to aggregate NOM, including Hg-NOM complexes, promoted Hg(II) removal from the dissolved fraction (<0.45 µm). Hg(II) removal in the presence of Cl- followed a stepwise mechanism. Weakly bound oxygen functional groups in NOM were outcompeted by Cl-, forming smaller-sized Hg(II)-chloro complexes, which could access additional intraparticle sorption sites. Therein, Cl- was outcompeted by S, which finally immobilized Hg(II) in SWP700 as confirmed by extended X-ray absorption fine structure spectroscopy. We conclude that in NOM containing oxic waters, with relatively high molar ratios of Cl-: NOM and Ca2+: NOM, Hg(II) removal can still be effective with SWP700.


Assuntos
Mercúrio , Carvão Vegetal , Íons , Mercúrio/química , Água , Madeira
9.
Environ Res ; 212(Pt E): 113640, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35688222

RESUMO

In order to explore the microbial diversity in industrial effluents, and on this basis, to verify the feasibility of tracking industrial effluents in sewer networks based on sequencing data, we collected 28 sewage samples from the industrial effluents relative to four factories in Shenzhen, China, and sequenced the 16S rRNA genes to profile the microbial compositions. We identified 5413 operational taxonomic units (OTUs) in total, and found that microbial compositions were highly diverse among samples from different locations in the sewer system, with only 107 OTUs shared by 90% of the samples. These shared OTUs were enriched in the phylum of Proteobacteria, the families of Comamonadaceae and Pseudomonadaceae, as well as the genus of Pseudomonas, with both degradation related and pathogenic bacteria. More importantly, we found differences in microbial composition among samples relevant to different factories, and identified microbial markers differentiating effluents from these factories, which can be used to track the sources of the effluents. This study improved our understanding of microbial diversity in industrial effluents, proved the feasibility of industrial effluent source tracking based on sequencing data, and provided an alternative technique solution for environmental surveillance and management.


Assuntos
Bactérias , Sequenciamento de Nucleotídeos em Larga Escala , Bactérias/genética , Monitoramento Ambiental , RNA Ribossômico 16S/genética , Esgotos/microbiologia
10.
Environ Res ; 207: 112211, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656634

RESUMO

Recent year, bacterial laccases are increasing interest in the field of industry and environmental applications especially decolorization of azo dyes. In industry, the dyes are present in stable nature including chemicals and lights. Due to these defects, the novel approaches are needed to removal of dyes before discharging into the environment. Among the various technologies, biological treatment methods and their strategies are very important, because of the decolorization and detoxification. Consecutively, biological mediated dyes removal are emerged with high potential especially microbes. Microbial laccases creates up new opportunities for their commercial applications. In this study, laccases were produced from Bacillus cereus (B. Cereus) and Pseudomonas parafulva (P. parafulva) by sub merged fermentation. For immobilization, the produced laccases were subjected to purify using 80% saturated ammonium sulphate and followed by dialysis. Then, crude laccases were immobilized through copper-alginate entrapment method. The maximum immobilized enzyme activity of the immobilized laccases were shown pH 8 at 50 °C and pH 7 at 40 °C for B. Cereus and P. parafulva respectively. In contrast, the normal enzyme activity was pH 10 at 40 °C and pH 8 at 40 °C were indicated for Bacillus cereus and P. parafulva respectively. Next, the free and immobilized laccases were performed the decolorization of three azo dyes T-blue, yellow GR and orange 3R, and exhibited that the 91.69 and 89.21% of Orange 3R were completely decolorized by both the B. Cereus and P. parafulva laccases when compared with free laccases enzymes. The confirmation of decolorization was monitored by UV-vis spectroscopy and FTIR spectroscopy, which clearly confirm the changes of peaks when compared with normal laccases. Finally, we have concluded that the B. Cereus and P. parafulva laccases are very important in azo dye decolorization and these used in future biological treatment of dyeing effluents.


Assuntos
Compostos Azo , Lacase , Compostos Azo/química , Bactérias , Biodegradação Ambiental , Cor , Corantes/química , Lacase/química , Indústria Têxtil , Têxteis
11.
J Basic Microbiol ; 62(3-4): 395-414, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34516028

RESUMO

Industrial wastewater consists of inorganic and organic toxic pollutants that pose a threat to environmental sustainability. The organic pollutants are a menace to the environment and life forms than the inorganic substances and pose teratogenic, mutagenic, carcinogenic, and other serious detrimental effects on the living entities, moreover, they have a gene-altering effect on aquatic life forms and affect the soil fertility and quality. Removal of varying effluents having recalcitrant contaminants with conventional treatment technologies is strenuous. In contrast to physical and chemical methods, biological treatment methods are environmentally friendly, versatile, efficient, and technically feasible with low operational costs and energy footprints. Biological treatment is a secondary wastewater treatment system that utilizes the metabolic activities of microorganisms to oxidize or reduce inorganic and organic compounds and transform them into dense biomass, which later can be removed by the sedimentation process. Biological treatment in bioreactors is an ex situ method of bioremediation and provides the benefits of continuous monitoring under controlled parameters. This paper attempts to provide a review of bioremediation technologies discussing most concerning widespread bioreactors and advances used for different industrial effluents with their comparative merits and limitations.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Biodegradação Ambiental , Reatores Biológicos , Resíduos Industriais , Águas Residuárias , Poluentes Químicos da Água/metabolismo
12.
J Environ Manage ; 319: 115677, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35816960

RESUMO

Metals are considered one of the biggest environmental problems, due to their toxicity and the complexity of removal. This study evaluated the bioaccumulation capacity of water contaminating metals by fungal isolates of Lentinus and Panus species, to elucidate the bioremediation processes of metal contaminated effluents. Initially, tests were performed with fungal isolates using a mixture of metals, aluminum, iron, copper, lead, chromium, nickel and zinc. Lentinus crinitus 154L.21 was the most promising fungus for the removal of metals in the mixture. Based on these data, the potential application of this fungus for the treatment of galvanic and tannery effluents was evaluated. For galvanic effluent, no detectable copper, chromium, and nickel was removed; however, for tannery effluents, reductions in aluminum concentrations from 204.1 to 3.7 mg L-1 (≅98% removal), chromium from 1199.6 to 20.4 mg L-1 (≅98% removal) and iron from 22.6 mg L-1 (100% removal) to an amount lower than the detection limit were observed. These data indicated that L. crinitus 154L.21 removes metals from industrial effluents, being an important route for bioremediation processes.


Assuntos
Metais Pesados , Níquel , Alumínio , Biodegradação Ambiental , Cromo/análise , Cobre , Florestas , Ferro , Metais , Metais Pesados/análise
13.
J Environ Manage ; 321: 115967, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35969973

RESUMO

Passive wastewater treatment systems are an alternative to costly and ineffective chemical wastewater treatment methods. Lignocellulosic waste materials (LWM) are often used in passive wastewater treatment systems as a cheap and accessible source of nutrients. LWM, such as spent mushroom compost and woodchips, have been implemented for the successful management of mildly alkaline effluents, which constitute a large fraction of industrial wastewater. The objective of the study was to provide an extensive study of the parameters in four types of commonly used LWM (raw and composted sawdust, spent mushroom compost and woodchips), which can be used in the planning of a passive wastewater treatment plant. LWM were shown to remove up to 90% Zn2+ and Pb2+ from a model solution and neutralize wastewater. Moreover, the LWM were inhabited by a physiologically diverse microbial consortium containing sulfate-reducing and cellulolytic microbes, which can influence the treatment process. Another purpose of this study was to construct a pilot wastewater treatment plant based on the use of LWM and gravel and to present its ability to effectively treat extremely alkaline flotation wastewater (pH = 12) originating from a lead and zinc mine located in Montenegro. The treated wastewater had a unique, but challenging chemical composition for passive treatment, as it was heavily contaminated with sulfates (∼1200 mg/L) and lead (∼1 g/L). The removal within the developed installation reached a rate of 66%, while the treated effluent, after initial neutralization, was maintained at a pH of approximately 7. Lead and zinc concentrations after treatment were also kept at levels required by Montenegrin law for wastewater disposal.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Lignina , Metais , Sulfatos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Zinco
14.
Environ Geochem Health ; 44(1): 57-68, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34131852

RESUMO

Present study was carried out to explore heavy metals pollution and potential ecological risk factors associated with agriculture soil irrigated with industrial effluents of Hayatabad industrial estate, Peshawar (HIEP) and Gadoon industrial estate, Sawabi (GIES) of Khyber-Pakhtunkhwa, Pakistan through multivariate geo-statistical tools. Diverse statistical tools like cluster analysis (HC) and principal component analysis (PCA), along with geo-statistical approaches were applied to highlight the geogenic and anthropogenic sources of pollution. The results indicated that concentration of heavy metals in target areas was significantly higher than control. Both soils had significant to moderate enrichment of heavy metals, while Gadoon soil had moderate to considerable ecological risk factor. The geo accumulation indices (Igeo) tendency for heavy metals in both target soil (Gadoon and Hayatabad) were the same. The Pb concentration of both target areas falls in the extremely severely polluted category because of the excessive presence of industries producing lead-containing products. Hence, this study indicated that the majority of toxic heavy metals contributed to soil pollution in the studied areas are coming from industrial and commercial activities.


Assuntos
Metais Pesados , Poluentes do Solo , Agricultura , Monitoramento Ambiental , Metais Pesados/análise , Solo , Poluentes do Solo/análise
15.
Environ Monit Assess ; 194(8): 586, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838845

RESUMO

The effluents discharged from Mansoura Company for Resins and Chemicals Industry were evaluated for drinking and irrigation purposes. Calcium-alginate beads were used for effluents treatment in this study. Young male rats were also allowed to drink effluents at different concentrations (10%, 50%, 100%) and treated 100% effluents with calcium-alginate for 11 weeks. Results indicated high concentrations of some physicochemical parameters and Cd, Co, Fe, Mn, Ni, Pb, and Zn in effluents that exceeded the permissible limits for drinking and irrigation purposes. Treatment by calcium-alginate alleviate heavy metals concentration but did not affect the physicochemical parameters. Depending on effluents concentration, the liver of young male rats showed high accumulation of Fe, Mn, Zn, Pb, Cd, Co, Cu, Cr, and Ni compared to the control group. Serum levels of liver enzymes, total bilirubin significantly increased while total protein, and albumin contents decreased in effluent groups. Liver concentrations of malondialdehyde and protein carbonyl significantly elevated along with significant decrease in superoxide dismutase, catalase, glutathione-S-transferase activities, and glutathione content. Moreover, growth and thyroid hormones were significantly reduced along with significant elevation in thyroid stimulating hormone. This was accompanied by significant decrease in the body weight, especially with 100% effluents concentration compared to control group. Also, histological investigations of both liver and thyroid gland using hematoxylin and eosin showed distortion in the structure of both organs especially with 50% and 100% effluent groups. However, treatment of effluents by calcium-alginate improved these changes. The study revealed that calcium-alginate are effective biosorbents for heavy metals and consequently decrease animal and human health hazards, but further studies are needed to alleviate physicochemical characteristics.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Qualidade da Água , Alginatos/química , Animais , Cádmio/análise , Cádmio/toxicidade , Cálcio/química , Cálcio/toxicidade , Monitoramento Ambiental/métodos , Glutationa , Chumbo/análise , Chumbo/toxicidade , Masculino , Metais Pesados/análise , Metais Pesados/toxicidade , Ratos , Poluentes Químicos da Água/análise , Purificação da Água/métodos
16.
Microb Cell Fact ; 20(1): 234, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34965861

RESUMO

The progress in industrialization everyday life has led to the continuous entry of several anthropogenic compounds, including dyes, into surrounding ecosystem causing arduous concerns for human health and biosphere. Therefore, microbial degradation of dyes is considered an eco-efficient and cost-competitive alternative to physicochemical approaches. These degradative biosystems mainly depend on the utilization of nutritive co-substrates such as yeast extract peptone in conjunction with glucose. Herein, a synergestic interaction between strains of mixed-culture consortium consisting of Rhodotorula sp., Raoultella planticola; and Staphylococcus xylosus was recruited in methylene blue (MB) degradation using agro-industrial waste as an economic and nutritive co-substrate. Via statistical means such as Plackett-Burman design and central composite design, the impact of significant nutritional parameters on MB degradation was screened and optimized. Predictive modeling denoted that complete degradation of MB was achieved within 72 h at MB (200 mg/L), NaNO3 (0.525 gm/L), molasses (385 µL/L), pH (7.5) and inoculum size (18%). Assessment of degradative enzymes revealed that intracellular NADH-reductase and DCIP-reductase were key enzymes controlling degradation process by 104.52 ± 1.75 and 274.04 ± 3.37 IU/min/mg protein after 72 h of incubation. In addition, azoreductase, tyrosinase, laccase, nitrate reductase, MnP and LiP also contributed significantly to MB degradation process. Physicochemical monitoring analysis, namely UV-Visible spectrophotometry and FTIR of MB before treatment and degradation byproducts indicated deterioration of azo bond and demethylation. Moreover, the non-toxic nature of degradation byproducts was confirmed by phytotoxicity and cytotoxicity assays. Chlorella vulgaris retained its photosynthetic capability (˃ 85%) as estimated from Chlorophyll-a/b contents compared to ˃ 30% of MB-solution. However, the viability of Wi-38 and Vero cells was estimated to be 90.67% and 99.67%, respectively, upon exposure to MB-metabolites. Furthermore, an eminent employment of consortium either freely-suspended or immobilized in plain distilled water and optimized slurry in a bioaugmentation process was implemented to treat MB in artificially-contaminated municipal wastewater and industrial effluent. The results showed a corporative interaction between the consortium examined and co-existing microbiota; reflecting its compatibility and adaptability with different microbial niches in different effluents with various physicochemical contents.


Assuntos
Corantes/metabolismo , Enterobacteriaceae/metabolismo , Azul de Metileno/metabolismo , Modelos Estatísticos , Rhodotorula/metabolismo , Staphylococcus/metabolismo , Animais , Biodegradação Ambiental , Linhagem Celular , Chlorella vulgaris/metabolismo , Chlorocebus aethiops , Técnicas de Cocultura , Ecossistema , Humanos , Resíduos Industriais , Azul de Metileno/toxicidade , Células Vero , Águas Residuárias/microbiologia , Purificação da Água/métodos
17.
Environ Res ; 191: 110142, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32898565

RESUMO

The illegal disposal of waste from textile industries having recalcitrant pollutants is a worldwide problem with more severity in developing nations. We used an ecofriendly method to synthesize silver nanoparticles (AgNPs) from a locally-isolated bacterial strain Bacillus marisflavi TEZ7 and employed them as photocatalysts to degrade not only synthetic azo dyes but also actual textile effluents followed by phytotoxicity evaluation and identification of degradation molecules. The strain TEZ7 was taxonomically identified through the 16S rRNA gene sequence analysis. Biogenic AgNPs were characterized for stabilizing molecules, crystal structure, size, shape and elemental composition by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The photocatalytic degradation efficiency of biogenic AgNPs for three azo dyes such as Direct Blue-1, Methyl Red, and Reactive Black-5 ranged between 54.14 and 96.92% after 5 h of sunlight exposure at a concentration of 100 mg/L. Moreover, the actual wastewater treatment analysis revealed that the 100 mg/L dose of AgNPs significantly decreased the concentration of various physico-chemical parameters of textile effluents such as pH, EC, chlorides, sulphates, hardness, BOD, COD, TSS and TDS. Furthermore, six intermediate molecules of methyl red degradation were identified by LC-MS and it was established by a pot study that these degradation molecules have no phytotoxic effects on rice plants. It was concluded that the AgNPs can be used as an efficient and low-cost strategy for the degradation of azo dyes containing textile wastewaters.


Assuntos
Nanopartículas Metálicas , Prata , Bacillus , Cromatografia Líquida , Nanopartículas Metálicas/toxicidade , RNA Ribossômico 16S , Prata/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem , Têxteis , Águas Residuárias
18.
J Environ Manage ; 255: 109906, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32063302

RESUMO

Waste fruit peels which are usually discarded as agricultural wastes were utilized to isolate cellulose. The varied amount of isolated cellulose was used as sustainable support with hydrothermally synthesized molybdenum sulphide (MoS2) nano-petals via in-situ approach. The phase purity of all synthesized nanostructures was confirmed by PXRD whereas different oxidation states along with the interaction of cellulose with the MoS2 were examined by XPS analysis. In order to evaluate the performance of catalyst, the photodegradation rate was calculated for RhB dye as well as industrial effluent in visible light. The upgradation in photocatalytic competence was found significant by cellulose supported MoS2 nanostructures as compared to bare MoS2 nano-petals due to slow recombination of electron hole pairs. The maximum rate was pronounced by employing the cellulose at an amount of ~500 mg as a support due to existence of an optimal point where the delay in charge recombination reaches maximum.


Assuntos
Molibdênio , Nanoestruturas , Celulose , Dissulfetos , Frutas
19.
Environ Monit Assess ; 192(12): 780, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33236212

RESUMO

The article is devoted to the pollution problems and the identification of the main sources of pollution of Boyuk Shor lake of the Absheron Peninsula under the ever-increasing rate of industrial development and urbanization. The purpose of the research was to determine the current ecological state of Boyuk Shor lake and adjacent territories. For this purpose, in June-August 2018, 36 samples were taken for analysis from water, bottom sediments of the lake, and soils of adjacent territories. The laboratory analysis revealed a high content of total hydrocarbons, toxic metals (Cd, Co, Hg, Cu), suspended solids, and other pollutants in the lake water samples. Quantitative and qualitative indicators of the lake are presented. The number of suspended particles in water samples was found to be more than 27-250 times higher than the maximum permissible concentration, and the amount of Hg is 180-286 times, Cd is 1-3.3 times, Cu is 1.7-4.8 times, and Co is 1.5-2.4 times higher than MPC. The heavy metal pollution of the soil and the taxonomic composition of the mesofauna of the surrounding area of Boyuk Shor lake were also studied. It was found that the composition of the group of soil invertebrates is very scarce, consisting only of insects (Arthropoda) (85.7%) and mollusks (Mollusca) (14.3%). The research results showed that the long-term negative impact has led to a violation of the ecological balance of the lake; it has lost its natural qualities, has become unsuitable for the flora and fauna of the lake and the surrounding area, and needs thorough cleaning and restoration.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Azerbaijão , China , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
20.
Int J Phytoremediation ; 21(14): 1442-1448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244333

RESUMO

The biomass of the cyanobacterium Spirulina platensis was used for metal removal from four industrial effluents with different chemical composition. The process of metal bioaccumulation (alive biomass) and biosorption (dry biomass) was studied at the native effluents pH as well as the pH 9.5. Metal uptake by S. platensis biomass was determined by means of neutron activation analysis (NNA). The obtained results show different affinity of biomass to metals presented in effluents. The results of this study have indicated that S. platensis is a very good candidate for the removal of heavy metals from complex industrial effluents.


Assuntos
Spirulina , Adsorção , Biodegradação Ambiental , Biomassa , Íons , Cinética
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