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1.
Ecotoxicol Environ Saf ; 205: 111338, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956867

RESUMO

Lead (Pb) is well-recognized for its great hazards to human and wildlife health. It has negative influences on multiple organs and systems of birds. Especially, lead exposure caused adverse impacts on bird reproduction. In this study, one week old female Japanese quails were randomly allocated into four groups and each group was respectively fed with 0, 50 ppm, 500 ppm and 1000 ppm Pb in drinking water for 36 days to determine the effects of chronic lead exposure on ovarian development and function. The results showed that Pb did accumulate in the ovary and ovarian development was delayed by high dose lead exposure (500 ppm and 1000 ppm). Moreover, high Pb dosage induced ovarian histopathological damages characterized by granulosa cells disorganization, follicle atresia and interstitial cell degeneration. Meanwhile, the concentration of estradiol (E2) was significantly decreased and mRNA levels of genes involved with ovarian steroidogenesis were significantly down-regulated by high concentration Pb. In addition, Pb exposure caused increasing cell apoptosis and significant changes of the expression of genes involved with cell death in the ovary. High dose Pb exposure also inhibited thyroid hormone release and disrupted ovarian thyroid deiodination apart from causing thyroid histopathological injury such as follicular deformation and atrophy. The study indicated that Pb might cause ovarian malfunction by inducing ovary and thyroid microstructural damages, thyroid hormone and estrogen release inhibition and ovarian steroidogenesis disruption.


Assuntos
Coturnix/metabolismo , Poluentes Ambientais/toxicidade , Estradiol/metabolismo , Expressão Gênica/efeitos dos fármacos , Chumbo/toxicidade , Ovário/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Adolescente , Animais , Apoptose/efeitos dos fármacos , Coturnix/genética , Coturnix/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Estradiol/genética , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/patologia , Humanos , Chumbo/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/patologia , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Ovário/patologia , Distribuição Aleatória , Reprodução/efeitos dos fármacos , Reprodução/genética , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Hormônios Tireóideos/genética
2.
Chemosphere ; 260: 127599, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32758775

RESUMO

Mercury, particularly methylmercury, can accumulate through food webs and generate high risks for species at higher trophic levels. Inorganic mercury can be methylated into the organic species methylmercury if suitable reducing conditions exist, for example, in hotspots like oilfields. We developed a conceptual model to conduct an ecological risk assessment based on the food web structure of the Shengli oilfield area, China. The model can identify species at risk and elucidate the sources of risks according to their diet. A risk rating criteria was developed based on the food web structure to categorize the different levels of risks for different species. As expected, the results indicate increasing risks for the biota higher in the food web hierarchy. Grasshoppers were mostly at no risk throughout the study area, whereas grubs at southwest were at minimal risks due to local high Hg concentration in the soil. Mantises, which are insect predators, were also at minimal risk. Herbivorous birds with similar feeding habits than grasshoppers were at no risk, but omnivorous and carnivorous birds were at moderate risk. The conceptual model is a useful tool to improve pollution remediation and establish risk control strategies based on ecological risks of the food web rather than just Hg concentrations in the environment.


Assuntos
Bioacumulação , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Mercúrio/análise , Compostos de Metilmercúrio/análise , Modelos Teóricos , Campos de Petróleo e Gás , Animais , China , Poluentes Ambientais/metabolismo , Cadeia Alimentar , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Medição de Risco
3.
Ecotoxicol Environ Saf ; 204: 111060, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768747

RESUMO

OBJECTIVE: Serratia sp. S2 is a wild strain with chromium resistance and reduction ability. Chromium(VI) metabolic-protein-coding gene ChrA and ChrT were cloned from Serratia sp. S2, and ligated with prokaryotic expression vectors pET-28a (+) and transformed into E. coli BL21 to construct ChrA, ChrT and ChrAT engineered bacteria. By studying the characteristics of Cr(VI) metabolism in engineered bacteria, the function and mechanism of the sole expression and coexpression of ChrA and ChrT genes were studied. METHODS: Using Serratia sp. S2 genome as template, ChrA and ChrT genes were amplified by PCR, and prokaryotic expression vectors was ligated to form the recombinant plasmid pET-28a (+)-ChrA, pET-28a (+)-ChrT and pET-28a (+)-ChrAT, and transformed into E. coli BL21 to construct ChrA, ChrT, ChrAT engineered bacteria. The growth curve, tolerance, and reduction of Cr(VI), the distribution of intracellular and extracellular Cr, activity of chromium reductase and intracellular oxidative stress in engineered bacteria were measured to explore the metabolic characteristics of Cr(VI) in ChrA, ChrT, ChrAT engineered bacteria. RESULTS: ChrA, ChrT and ChrAT engineered bacteria were successfully constructed by gene recombination technology. The tolerance to Cr(VI) was Serratia sp. S2 > ChrAT ≈ ChrA > ChrT > Control (P < 0.05), and the reduction ability to Cr(VI) was Serratia sp. S2 > ChrAT ≈ ChrT > ChrA (P < 0.05). The chromium distribution experiments confirmed that Cr(VI) and Cr(III) were the main valence states. Effect of electron donors on chromium reductase activity was NADPH > NADH > non-NAD(P)H (P < 0.05). The activity of chromium reductase increased significantly with NAD(P)H (P < 0.05). The Glutathione and NPSH (Non-protein Sulfhydryl) levels of ChrA, ChrAT engineered bacteria increased significantly (P < 0.05) under the condition of Cr(VI), but there was no significant difference in the indexes of ChrT engineered bacteria (P > 0.05). CONCLUSION: ChrAT engineered bacteria possesses resistance and reduction abilities of Cr(VI). ChrA protein endows the strain with the ability to resist Cr(VI). ChrT protein reduces Cr(VI) to Cr(III) by using NAD(P)H as electronic donor. The reduction process promotes the production of GSH, GSSG and NPSH to maintain the intracellular reduction state, which further improves the Cr(VI) tolerance and reduction ability of ChrAT engineered bacteria.


Assuntos
Proteínas de Bactérias/genética , Compostos de Cromo/metabolismo , Poluentes Ambientais/metabolismo , Genes Bacterianos , Proteínas de Membrana/genética , Microrganismos Geneticamente Modificados/genética , Serratia/genética , Biodegradação Ambiental , Escherichia coli/genética , Escherichia coli/metabolismo , Microrganismos Geneticamente Modificados/metabolismo , Modelos Teóricos , Oxirredução , Oxirredutases/metabolismo , Serratia/metabolismo
4.
Ecotoxicol Environ Saf ; 204: 110965, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798747

RESUMO

Toxic and essential trace elements are associated with human fertility. However, limited studies have been conducted on the relationship between trace elements and in vitro fertilization (IVF) outcomes in the Chinese population. In this exploratory study, 103 couples who underwent IVF/intracytoplasmic sperm injection (ICSI) treatment in our reproductive center were recruited. Serum and follicular fluid (FF) samples and seminal plasma samples were collected from the female and male partners, respectively, on the day of oocyte retrieval. Concentrations of chromium (Cr), nickel (Ni), arsenic (As), selenium (Se), cadmium (Cd), and lead (Pb) in the specimens were measured by inductively coupled plasma-mass spectrometry. Generalized linear models were used to evaluate the associations of toxic and essential trace element levels with the intermediate parameters and outcomes of IVF at both the sex-specific and couple levels. The Cr level in the serum of the female partners was inversely associated with the count of mature oocytes retrieved (p for trend = 0.033). In terms of embryo development, As concentrations in female serum and FF were inversely associated with the probabilities to obtain good-quality cleavage embryos (p for trend < 0.01). There were significant correlations between follicular Se concentrations and seminal As concentrations and higher quality cleavage embryos (p for trend < 0.01). Moreover, a positive correlation was observed between the female serum Se concentrations and blastocyst formation (p for trend = 0.031). In contrast, a higher follicular Se level was negatively correlated with embryo development at the blastocyst stage (p for trend < 0.01). Regarding the clinical outcomes, a positive association of Se levels in seminal plasma and a negative association of follicular Cd levels was observed with the probabilities of pregnancy (p for trend = 0.006 and 0.035, respectively) and live birth (p for trend = 0.014 and 0.027, respectively). The results indicate that exposure to toxic elements (Cr, As and Cd) is associated with intermediate parameters and outcomes of IVF. Furthermore, male Se exposure may be related to better pregnancy outcomes.


Assuntos
Poluentes Ambientais/metabolismo , Líquido Folicular/química , Sêmen/química , Soro/química , Oligoelementos/metabolismo , Adulto , Poluentes Ambientais/sangue , Feminino , Fertilização In Vitro , Humanos , Masculino , Oligoelementos/sangue , Adulto Jovem
5.
Ecotoxicol Environ Saf ; 205: 111149, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32829210

RESUMO

Exposure to heavy metals was reported to be associated with heart rate variability (HRV) alteration. However, possible pathway of such association remains unclear. In this research, we investigated the possible role of lipid peroxidation in the associations between urinary heavy metals and HRV. We performed a cross-sectional study using baseline data of Wuhan-Zhuhai cohort. Urinary heavy metals (including lead, barium, antimony, cadmium, zinc, copper, iron and manganese), urinary 8-iso-prostaglandin-F2α levels (common biomarker for lipid peroxidation) and HRV indices (SDNN, r-MSSD, low frequency, high frequency and total power) were measured among 3022 participants. We conducted multivariable linear regression models to quantify associations between urinary 8-iso-prostaglandin-F2α (8-iso-PGF2α) and heavy metals or HRV indices. The potential role of 8-iso-PGF2α in the association of urinary heavy metals with HRV was evaluated through mediation analyses. After adjusting for potential confounders, urinary manganese, iron, copper, zinc, cadmium, antimony and barium were identified to be negatively associated with one or more HRV parameters. Each one-unit growth of log-transformed levels of urinary manganese, iron, copper, zinc, antimony and barium was associated with a 1.9%, 1.5%, 4.7%, 4.0%, 2.7% and 1.3% decrease in SDNN, respectively. We observed positive dose-response relationships between all eight urinary heavy metals and 8-iso-PGF2α, as well as negative association of urinary 8-iso-PGF2α with SDNN and total power (all P trend<0.05). The proportions mediated by 8-iso-PGF2α on SDNN were 4.6% for manganese, 9.3% for iron, 19.8% for antimony and 11.0% for barium. The proportions mediated by 8-iso-PGF2α on total power were 6.9% for manganese and 10.1% for cadmium (all P value < 0.05). This study suggested that urinary manganese, iron, copper, zinc, cadmium, antimony and barium were negatively associated with HRV indices. Lipid peroxidation may partly mediate the associations of urinary manganese, iron, cadmium, antimony and barium with specific HRV indices.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/toxicidade , Frequência Cardíaca , Peroxidação de Lipídeos , Metais Pesados/toxicidade , Adulto , Antimônio , Biomarcadores/metabolismo , Cádmio , Cobre , Estudos Transversais , Dinoprosta/análogos & derivados , Exposição Ambiental/análise , Poluentes Ambientais/metabolismo , Feminino , Humanos , Ferro , Masculino , Manganês , Metais Pesados/metabolismo , Pessoa de Meia-Idade , Zinco
6.
Ecotoxicol Environ Saf ; 205: 111138, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32836156

RESUMO

Nitrobenzene, nitrotoluenes and nitrobenzoic acid are toxic and mutagenic. Their removal from the environment is necessary to avoid health and environmental damage. In this study, Cupriavidus strain a3 was found to utilize 2-nitrotoluene (2NT), 3-nitrotoluene (3NT), 4-nitrotoluene (4NT), nitrobenzene (NB) and 2-nitrobenzoic acid (2NBA) as carbon and nitrogen source, resulting in their detoxification. The metabolism involved reductive transformation of nitroaromatics to the corresponding amines followed by cleavage of amino group to release ammonia. Cell free extract showed nitroreductase activity in the range of 310-389 units/mg. NB was reduced to form benzamine and 4-aminophenol, 2NT was reduced to 2-aminotoluene, whereas 2NBA was reduced to form 2-aminobenzoic acid. Similarly, 3NT was metabolized to 3-aminotoluene and 2-amino-4-methylphenol, while 4NT was reduced to 4-nitrosotoluene and 4-aminotoluene. Cytotoxicity and apoptosis assays using Jurkat cell line, and Ames test were used to evaluate the detoxification of nitroaromatics during biodegradation. Biodegradation with Cupriavidus resulted in 2.6-11 fold increase in cell viability, 1.3-2.3 fold reduction in apoptosis, 1.6-55 fold reduction in caspase-3 activation, and complete disappearance of mutagenic activity. In soil microcosm, bioaugmentation with Cupriavidus resulted in 16-59% degradation of various nitroaromatics, as against <14% degradation without bioaugmentation. Thus, the present study reflects promising capability of Cupriavidus strain a3 in degradation and detoxification of multiple nitroaromatics.


Assuntos
Biodegradação Ambiental , Cupriavidus/fisiologia , Poluentes Ambientais/metabolismo , Nitrobenzenos , Solo , Tolueno/análogos & derivados , Toluidinas
7.
Bull Environ Contam Toxicol ; 105(3): 366-371, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32840648

RESUMO

Ground venison packets from shotgun- and archery-harvested White-tailed Deer in Illinois in 2013 and 2014 were analyzed for metal contamination. Radiographs indicated that 48% of 27 ground venison packets from 10 shotgun-harvested deer contained metal fragments, while none of the 15 packets from three archery-harvested deer contained fragments. ICP-MS analysis verified that all metal fragments from seven of the venison samples from shotgun-harvested deer were composed of lead, with average concentrations from 1.04 to 8.42 µg g-1, dry weight. A single serving of ground venison containing one of these metal fragments embedded in it would be predicted to have a lead concentration ranging from 6.4 to 51.8 µg g-1. Sixty percent of 20 commercial meat processing plants surveyed by phone in 2018 and 2019 indicated that they mixed venison from multiple deer when preparing ground venison products. However, our results do not show any cross-contamination in archery-harvested ground venison processed prior to the firearm hunting seasons.


Assuntos
Cervos/metabolismo , Poluentes Ambientais/metabolismo , Chumbo/metabolismo , Carne/análise , Animais , Illinois , Chumbo/análise
8.
Chemosphere ; 255: 127003, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679629

RESUMO

In this study, we assessed the presence of 14 phthalate metabolites in the urine of 104 lactating mothers from Valencia (Spain) who took part in the human biomonitoring project BETTERMILK. Nine of the metabolites studied showed detection frequencies >80%, whereas the rest of the metabolites presented low detection frequencies (<5%). The concentrations ranged from

Assuntos
Monitoramento Biológico , Aleitamento Materno/estatística & dados numéricos , Exposição Materna/estatística & dados numéricos , Ácidos Ftálicos , Adulto , Coleta de Dados , Dietilexilftalato , Exposição Ambiental/análise , Poluentes Ambientais/metabolismo , Feminino , Humanos , Lactação , Mães , Embalagem de Produtos , Medição de Risco , Espanha
9.
Artigo em Inglês | MEDLINE | ID: mdl-32656653

RESUMO

Aerial insectivorous birds such as swallows have been the steepest declining groups of birds in North America over the last 50 years but whether such declines are linked to contaminants has not been examined. We sampled feathers from five species of swallow at multiple locations to assess total mercury [THg] exposure for adults during the non-breeding season, and for juveniles on the breeding grounds. We assessed Hg exposure to juvenile birds in crop- and grass-dominated landscapes to determine if land-use practices influenced feather [THg]. We assayed feathers for stable isotopes (δ2H, δ13C, δ15N) as proxies for relative habitat use and diet to determine their potential influence on feather [THg]. Feather [THg] was highest in adult bank swallows (Riparia riparia) and purple martins (Progne subis) from Saskatchewan and adult cliff swallows (Petrochelidon pyrrhonota) from western regions, indicating differential exposure to Hg on the non-breeding grounds. Juvenile bank, barn (Hirundo rustica) and tree (Tachycineta bicolor) swallows had lower feather [THg] in crop-dominated landscapes than grass-dominated landscapes in Saskatchewan, potentially resulting from lower use of wetland-derived insects due to wetland drainage and intensive agriculture. Feather [THg] was related to juvenile feather stable isotopes for several species, suggesting complex interactions with diet and environmental factors. Many individuals had feather [THg] values >2 µg/g, a threshold at which deleterious effects may occur. Our findings indicate differential Hg exposure among species of swallow, regions and land-uses and highlight the need for additional research to determine dietary and finer-scale land-use impacts on individual species and populations.


Assuntos
Exposição Ambiental , Poluentes Ambientais/metabolismo , Plumas/química , Mercúrio/metabolismo , Andorinhas/metabolismo , Migração Animal , Animais , Canadá , Monitoramento Ambiental , Feminino , Masculino , Estações do Ano , Washington
10.
Ecotoxicol Environ Saf ; 203: 110975, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678756

RESUMO

Manganese (Mn) produces cholinergic neuronal loss in basal forebrain (BF) region that was related to cognitive dysfunction induced after single and repeated Mn treatment. All processes that generate cholinergic neuronal loss in BF remain to be understood. Mn exposure may produce the reduction of BF cholinergic neurons by increasing amyloid beta (Aß) and phosphorylated Tau (pTau) protein levels, altering heat shock proteins' (HSPs) expression, disrupting proteasome P20S activity and generating oxidative stress. These mechanisms, described to be altered by Mn in regions different than BF, could lead to the memory and learning process alteration produced after Mn exposure. The research performed shows that single and repeated Mn treatment of SN56 cholinergic neurons from BF induces P20S inhibition, increases Aß and pTau protein levels, produces HSP90 and HSP70 proteins expression alteration, and oxidative stress generation, being the last two effects mediated by NRF2 pathway alteration. The increment of Aß and pTau protein levels was mediated by HSPs and proteasome dysfunction. All these mechanisms mediated the cell decline observed after Mn treatment. Our results are relevant because they may assist to reveal the processes leading to the neurotoxicity and cognitive alterations observed after Mn exposure.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Prosencéfalo Basal/efeitos dos fármacos , Neurônios Colinérgicos/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Manganês/toxicidade , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas tau/metabolismo , Animais , Prosencéfalo Basal/metabolismo , Prosencéfalo Basal/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Manganês/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos
11.
Chemosphere ; 259: 127485, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32650164

RESUMO

Sub-lethal toxic impacts of chromium on hematological, biochemical and histological parameters were analyzed in the female small Indian mongoose (Urva auropuctatus) residing contaminated environment of tannery industry. Chromium bioaccumulation in the blood, liver and kidney tissue of the exposed mongooses was found elevated compared to the control mongooses' tissues. Total body weight (75.7%), liver weight (83.6%) as well as HSI (68.1%), RSI (86.2%) and the platelets counts (59.7%) were found significantly elevated, with significantly reduced RBCs (59.6%), and WBCs (64%). LFT and RFT were also found abnormal, moreover, the histopathological injuries had been distinct inside the kidney (>75%) and hepatic (>75%) tissues of exposed animals. Shrinkage and vacuolization (>75%) inside the hepatocyte expanded sinusoidal spaces and nuclear pyknosis (>75%) was evident within the hepatic tissue. Hypertrophy of epithelial cells of renal tubules and inter-renal cells of the head kidney with a reduction in tubular lumens (>75%) and vacuolization of tubules were witnessed within the kidney section. Atrophy inside the kidney inter-renal cells, glomeruli compression within the Bowman's capsules (>75%) following the necrosis in hematopoietic tissues were found in exposed animals. The present findings indicate that chronic exposure to chromium induces severe anemia, decreased serum protein concentration, hepatic and renal tissue histopathology, impairing the vital capabilities of liver, metabolic regulation, excretion, and stress homeostasis maintenance of which within the long-run may posture a severe risk to animal well-being then distress their inhabitants.


Assuntos
Cromo/toxicidade , Poluentes Ambientais/toxicidade , Herpestidae/fisiologia , Animais , Cromo/metabolismo , Poluentes Ambientais/metabolismo , Poluição Ambiental , Feminino , Herpestidae/metabolismo , Rim/metabolismo , Fígado/metabolismo , Masculino
12.
Environ Health ; 19(1): 83, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32664952

RESUMO

BACKGROUND: Parabens are a group of esters of para-hydroxybenzoic acid utilized as antimicrobial preservatives in many personal care products. Epidemiological studies regarding the adverse effects of parabens on fetuses are limited. The aim of this study was to determine the association between placental paraben exposure and birth outcomes. We assessed paraben concentrations in placental tissue, which potentially gives a better understanding of fetal exposure than the maternal urinary concentrations which are the current golden standard. METHODS: Placental tissue was collected immediately after birth from 142 mother-child pairs from the ENVIRONAGE birth cohort. The placental concentrations of four parabens (methyl (MeP), ethyl (EtP), propyl (PrP), and butyl (BuP)) were determined by ultra-performance liquid chromatography coupled with tandem mass-spectrometry. Generalized linear regression models were used to determine the association between paraben exposure levels and birth outcomes. RESULTS: The geometric means of placental MeP, EtP, PrP, and BuP were 1.84, 2.16, 1.68 and 0.05 ng/g tissue, respectively. The sum of parabens (∑ parabens, including MeP, EtP and PrP) was negatively associated with birth weight in newborn girls (- 166 g, 95% CI: - 322, - 8.6, p = 0.04) after adjustment for a priori selected covariates. The sum of parabens was negatively associated with head circumference (- 0.6 cm, 95% CI: - 1.1, - 0.2, p = 0.008) and borderline associated with birth length (- 0.6 cm, 95% CI:-1.3, 0.1, p = 0.08). In newborn girls the placental concentration of EtP was negatively associated with head circumference (- 0.6 cm, 95% CI:-1.1, - 0.1, p = 0.01) and borderline significantly associated with birth weight and birth length. Lastly, placental EtP and ∑parabens were negatively associated with placental weight in newborn girls but not in newborn boys (- 45.3 g, 95% CI:-86.2, - 4.4, p = 0.03). CONCLUSION: The negative association between maternal paraben exposure and birth outcomes warrants further research and follow-up over time to determine long term effects of gestational exposure to parabens.


Assuntos
Peso ao Nascer , Poluentes Ambientais/metabolismo , Cabeça/anatomia & histologia , Exposição Materna , Parabenos/metabolismo , Placenta/química , Bélgica , Estudos de Coortes , Monitoramento Ambiental , Feminino , Humanos , Recém-Nascido , Gravidez
13.
Ecotoxicol Environ Saf ; 203: 110997, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32684518

RESUMO

A novel study on biodegradation of 30 mg L-1 of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) mixture (celecoxib, diclofenac and ibuprofen) by two wood-rot fungi; Ganoderma applanatum (GA) and Laetiporus sulphureus (LS) was investigated for 72 h. The removal efficiency of celecoxib, diclofenac and ibuprofen were 98, 96 and 95% by the fungal consortium (GA + LS). Although, both GA and LS exhibited low removal efficiency (61 and 73% respectively) on NSAIDs. However, 99.5% degradation of the drug mixture (NSAIDs) was achieved on the addition of the fungal consortium (GA + LS) to the experimental set-up. Overall, LS exhibited higher degradation efficiency; 92, 87, 79% on celecoxib, diclofenac and ibuprofen than GA with 89, 80 and 66% respectively. Enzyme analyses revealed significant induction of 201, 180 and 135% in laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP) by the fungal consortium during degradation of the NSAIDs respectively. The experimental data showed the best goodness of fit when subjected to Langmuir (R2 = 0.980) and Temkin (R2 = 0.979) isotherm models which suggests monolayer and heterogeneous nature exhibited by the mycelia during interactions with NSAIDs. The degradation mechanism followed pseudo-second-order kinetic model (R2 = 0.987) indicating the strong influence of fungal biomass in the degradation of NSAIDs. Furthermore, Gas Chromatography-Mass Spectrometry (GCMS) and High-Performance Liquid Chromatography (HPLC) analyses confirmed the degraded metabolic states of the NSAIDs after treatment with GA, LS and consortium (GA + LS). Hence, the complete removal of NSAIDs is best achieved in an economical and eco-friendly way with the use of fungi consortium.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Poluentes Ambientais/análise , Ganoderma/enzimologia , Ganoderma/crescimento & desenvolvimento , Lignina/metabolismo , Madeira/microbiologia , Anti-Inflamatórios não Esteroides/metabolismo , Biodegradação Ambiental , Biomassa , Poluentes Ambientais/metabolismo , Indução Enzimática/efeitos dos fármacos , Cinética , Lacase/biossíntese , Modelos Biológicos , Peroxidases/biossíntese
14.
Arch Microbiol ; 202(9): 2471-2480, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32613418

RESUMO

A synergy of biodegradation and electron shuttle systems is a promising strategy for eliminating pollutants including chlorinated aromatic compounds. The present work studies the degradation products of 3-chlorobenzoic acid by Pseudomonas putida in the presence of an electron shuttle system (ESS) composed of citrate and pyruvate as electron donors and the pollutant as an electron acceptor. Chromatographic results showed different pathways involved in the biodegradation process under the influence of electron shuttle systems. These routes depend on oxidation and reduction reactions for output byproducts to be easily mineralized by the bacterium under investigation. A nucleotide sequence with about 380 bp of a ton B gene was detected in P. putida and it resembles Escherichia coli Ton B. The relatedness tree of the selected gene reveals a high similarity and is comparable to P. aeruginosa (100%) and the highest variation with that of P. citronellolis (21.99%). Accordingly, in the presence of electron shuttle systems, the genes responsible for bacterial influx were activated to ease the biodegradation process. In an application model, the remediated-water samples were handled by two recycling processes using Scenedesmus obliquus and Trigonella foenum-graecum to evaluate the efficiency of this non-conventional treatment. In conclusion, this strategy succeeded in remediating the polluted water with chlorinated aromatic compounds for further applications.


Assuntos
Biodegradação Ambiental , Clorobenzoatos/metabolismo , Genes Bacterianos/genética , Pseudomonas putida/metabolismo , Elétrons , Poluentes Ambientais/metabolismo , Oxirredução , Pseudomonas/genética , Pseudomonas aeruginosa/genética , Pseudomonas putida/classificação , Pseudomonas putida/genética
15.
Ecotoxicol Environ Saf ; 202: 110864, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32610224

RESUMO

An increasing amount of Fluoranthene (Fla) and Benz(a)anthracene (BaA) is being produced and used, eventually entering the soil sediments. The accumulation of Fla and BaA will cause poisoning to typical enzymes (α-Amylase) and organisms (Eisenia fetida) in soil. However, the studies about exploring and comparing the different effects of Fla, BaA and their joint effect at different levels are rarely reported. In this paper, the different effects of Fla, BaA and their mixed pollutant on α-Amylase were evaluated and compared at the molecular level, and the effect of Fla-BaA to the antioxidant system of earthworm (Eisenia fetida) was investigated from the aspects of concentration and exposure time at the animal level. The results showed that Fla-BaA had the greatest influence on the skeleton structure and the microenvironment of amino acid residue of α-Amylase compared to Fla and BaA, and in the mixed pollutant system, the joint effect mode was additive mode. The inhibitory effect of Fla-BaA on the activity of α-Amylase was also stronger than that of the system alone. The assays at the animal level showed that low concentrations (below 5 mg/kg) of Fla-BaA increased the activity of GSH-Px and SOD while high concentrations inhibited their activity. The POD that was activated throughout the experiment period suggested its key role in the earthworm antioxidant system. Changes in T-AOC and MDA showed that long-term and high-dose of Fla-BaA exposure inhibited the antioxidant capacity of Eisenia fetida, causing lipid peroxidation and damage to cells.


Assuntos
Benzo(a)Antracenos/toxicidade , Fluorenos/toxicidade , Poluentes do Solo/toxicidade , Animais , Antracenos , Antioxidantes/metabolismo , Poluentes Ambientais/metabolismo , Poluição Ambiental , Peroxidação de Lipídeos/efeitos dos fármacos , Oligoquetos/efeitos dos fármacos , Solo/química , Testes de Toxicidade
16.
Chemosphere ; 257: 127218, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32497833

RESUMO

The chemical contamination of terrestrial ecosystems is a great concern as these ecosystems are the target of most of the pollutants derived from anthropogenic activities such as pesticides, heavy metals, nanoparticles, and others. Terrestrial gastropods are considered to be excellent sentinel organisms for biological monitoring of environmental pollution, as they have the ability to accumulate chemicals in their tissues and exhibit a great potential to evaluate the ecological effects of pollutants in terrestrial ecosystems. The use of biomarkers as sensitive parameters to estimate the exposure or resulting effects of chemicals have received considerable attention. The successful biomarker must be applicable in the laboratory and field conditions. Many biomarkers have been examined to understand the adverse effects of pollutants. In this review, we shed light on different types of biomarkers, such as oxidative stress, genotoxicity and immunotoxicity as diagnostic tools for monitoring the impacts of pollution. These biomarkers can provide information about early detection and quantification of these impacts during their initial manifestations and can facilitate the implementation of a rapid preventive and/or restorative responses in the affected ecosystems, as well as single or multiple biomarkers can be integrated into routine monitoring programs.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Gastrópodes/fisiologia , Animais , Biomarcadores , Dano ao DNA , Ecossistema , Poluentes Ambientais/toxicidade , Poluição Ambiental , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/farmacologia
17.
Arch Microbiol ; 202(8): 2033-2058, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32506150

RESUMO

Polyaromatic hydrocarbons (PAHs) are considered as hazardous organic priority pollutants. PAHs have immense public concern and critical environmental challenge around the globe due to their toxic, carcinogenic, and mutagenic properties, and their ubiquitous distribution, recalcitrance as well as persistence in environment. The knowledge about harmful effects of PAHs on ecosystem along with human health has resulted in an interest of researchers on degradation of these compounds. Whereas physico-chemical treatment of PAHs is cost and energy prohibitive, bioremediation i.e. degradation of PAHs using microbes is becoming an efficient and sustainable approach. Broad range of microbes including bacteria, fungi, and algae have been found to have capability to use PAHs as carbon and energy source under both aerobic and anaerobic conditions resulting in their transformation/degradation. Microbial genetic makeup containing genes encoding catabolic enzymes is responsible for PAH-degradation mechanism. The degradation capacity of microbes may be induced by exposing them to higher PAH-concentration, resulting in genetic adaptation or changes responsible for high efficiency towards removal/degradation. In last few decades, mechanism of PAH-biodegradation, catabolic gene system encoding catabolic enzymes, and genetic adaptation and regulation have been investigated in detail. This review is an attempt to overview current knowledge of microbial degradation mechanism of PAHs, its genetic regulation with application of genetic engineering to construct genetically engineered microorganisms, specific catabolic enzyme activity, and application of bioremediation for reclamation of PAH-contaminated sites. In addition, advanced molecular techniques i.e. genomic, proteomic, and metabolomic techniques are also discussed as powerful tools for elucidation of PAH-biodegradation/biotransformation mechanism in an environmental matrix.


Assuntos
Bactérias , Biodegradação Ambiental , Microbiologia Ambiental , Poluentes Ambientais/metabolismo , Fungos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biotransformação , Fungos/genética , Fungos/metabolismo , Engenharia Genética , Genoma Bacteriano/genética , Genoma Fúngico/genética
18.
Arch Environ Contam Toxicol ; 79(2): 184-194, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32494886

RESUMO

The widespread human exposure to perfluoroalkyl acids (PFAAs) has led to increasing public concern. In this study, we present a comprehensive measurement of total fluorine (TF), extractable organic fluorine (EOF), identified organic fluorine (IOF, total concentration of identified PFAAs quantified as fluorine) and 11 target PFAAs in human serum (n = 60), hair (n = 49) and nails (n = 39) collected from non-occupation exposed volunteers in 10 cities of Guangdong Province, China. The results indicated that EOF was the major form of fluorine in serum, accounting for 70-80% of TF. The levels of IOF contributed less than 10% of EOF. Perfluorooctane sulfonic acid (PFOS) was found to be the dominant PFAA with mean concentration of 23 ng·mL-1 in serum, 35 ng·g-1 in hair and 33 ng·g-1 in nail, respectively. Short-chain PFAAs (C ≤ 10) were the predominant PFAAs in three matrices. Levels of PFOS, perfluorohexane sulfonic acid (PFHxS), perfluoroundecanoic acid (PFUdA) and perfluorotridecanoic acid (PFTrDA) in males are significantly higher than those in females (p < 0.01). Significant positive correlations were observed between nail and serum for PFOS (p < 0.01), perfluorooctanoic acid (PFOA) (p < 0.05) and PFHxS (p < 0.01), suggesting that human nails, a noninvasive sample, are a promising bio-indicator for PFAA risk assessment.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Adulto , Ácidos Alcanossulfônicos/sangue , Ácidos Alcanossulfônicos/química , Ácidos Alcanossulfônicos/metabolismo , Caprilatos/sangue , Caprilatos/química , Caprilatos/metabolismo , China , Cidades , Ácidos Graxos/sangue , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Fluorcarbonetos/sangue , Fluorcarbonetos/química , Fluorcarbonetos/metabolismo , Cabelo , Humanos , Masculino , Unhas , Adulto Jovem
19.
Ecotoxicol Environ Saf ; 201: 110799, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32544743

RESUMO

Mercury (Hg) is an environmental contaminant that poses great risk to human health. However, it is still widely used in artisanal gold-mining enterprises around the world, especially in developing countries. Methylmercury (MeHg) is produced environmentally by biomethylation of inorganic Hg present in water sediments, leading to its subsequent accumulation in the aquatic food chain. Due to its high metabolic rate, the Central Nervous System (CNS) is one of the main targets of MeHg. In the present study, we investigate the impact of chronic MeHg intoxication on NADPH diaphorase (NADPH-d) activity and astrocyte mobilization in the visual cortex of the rat. After 60 days of MeHg administration by oral gavage (0.04 mg/kg/day), tissue samples containing the visual cortex were submitted to measurements of Hg levels, NADPH-d activity, and GFAP immunohistochemistry for identification of astrocytes. MeHg intoxication was associated with increased Hg deposits and with reduced NADPH-d neuropil reactivity in the visual cortex. A morphometric analysis suggested that NADPH-d-positive neurons were mostly spared from MeHg harmful action and intoxicated animals had astrocytic activation similar to the control group. The decrease in NADPH-d neuropil reactivity may be due to the negative effect of chronic MeHg poisoning on both the synthesis and transport of this enzyme in afferent pathways to the visual cortex. The relative resistance of NADPH-d-reactive neurons to chronic MeHg intoxication may be associated with peculiarities in cell metabolism or to a protective role of nitric oxide, safeguarding those neurons from Hg deleterious effects.


Assuntos
Astrócitos/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Compostos de Metilmercúrio/toxicidade , NADPH Desidrogenase/metabolismo , Neurônios/efeitos dos fármacos , Córtex Visual/efeitos dos fármacos , Animais , Astrócitos/enzimologia , Comportamento Animal/efeitos dos fármacos , Poluentes Ambientais/metabolismo , Ouro , Humanos , Masculino , Compostos de Metilmercúrio/metabolismo , Mineração , Neurônios/enzimologia , Ratos , Ratos Wistar , Córtex Visual/enzimologia , Córtex Visual/patologia
20.
Chemosphere ; 259: 127419, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32593003

RESUMO

Carbofuran is one of the most toxic broad-spectrum and systemic N-methyl carbamate pesticide, which is extensively applied as insecticide, nematicide and acaricide for agricultural, domestic and industrial purposes. It is extremely lethal to mammals, birds, fish and wildlife due to its anticholinesterase activity, which inhibits acetyl-cholinesterase and butyrylcholinesterse activity. In humans, carbofuran is associated with endocrine disrupting activity, reproductive disorders, cytotoxic and genotoxic abnormalities. Therefore, cleanup of carbofuran-contaminated environments is of utmost concern and urgently needs an adequate, advanced and effective remedial technology. Microbial technology (bacterial, fugal and algal species) is a very potent, pragmatic and ecofriendly approach for the removal of carbofuran. Microbial enzymes and their catabolic genes exhibit an exceptional potential for bioremediation strategies. To understand the specific mechanism of carbofuran degradation and involvement of carbofuran hydrolase enzymes and genes, highly efficient genomic approaches are required to provide reliable information and unfold metabolic pathways. This review briefly discusses the carbofuran toxicity and its toxicological impact into the environment, in-depth understanding of carbofuran degradation mechanism with microbial strains, metabolic pathways, molecular mechanisms and genetic basis involved in degradation.


Assuntos
Biodegradação Ambiental , Carbofurano/toxicidade , Inibidores da Colinesterase/toxicidade , Poluentes Ambientais/toxicidade , Acetilcolinesterase/metabolismo , Animais , Carbamatos , Carbofurano/metabolismo , Inibidores da Colinesterase/metabolismo , Poluentes Ambientais/metabolismo , Humanos , Hidrolases , Inseticidas/metabolismo , Inseticidas/toxicidade , Redes e Vias Metabólicas
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