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1.
Chemosphere ; 262: 127749, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805655

RESUMO

Beans of cacao (Theobroma cacaoL.) are used to produce a variety of chocolate products. Bioaccumulation of metals at toxic levels through the consumption of contaminated products has been identified as a health concern in humans. Both metal diversity and concentration as well as their interactions in the soil influence essential and non-essential metal uptake in plants; but the effects of these on bioaccumulation of metals in cacao is not understood across diverse soil types. In this study eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were investigated in 12 soil subgroups belonging to four soil orders across 15 locations in Trinidad, with the aim to investigate the effect of soil metal diversity and concentration on metal bioaccumulation in cacao. Soil metals were extracted using five methods (aqua regia, DTPA, Mehlich 3, nitric acid, and water). Cacao leaf metal concentrations were determined using the USEPA 3052 method. Metal extraction efficiency ranged between methods with aqua regia ≥ nitric acid > Mehlich 3 ≥ DTPA ≥ water across all metals. The soil extraction method that best predicted cacao leaf metal concentrations varied with the metal - Mehlich 3 or DTPA for Cd, Ni, Zn; aqua regia, Mehlich 3, or nitric acid for Pb, and water for Mn. A stepwise regression analysis showed that plant metal concentration can be predicted using soil physicochemical characteristics as well as the concentration of metals in the soil. The importance of soil type on cacao leaf metal bioaccumulation is discussed.


Assuntos
Bioacumulação , Cacau/química , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Disponibilidade Biológica , Cacau/efeitos dos fármacos , Cacau/crescimento & desenvolvimento , Humanos , Metais Pesados/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Trinidad e Tobago
2.
Bull Environ Contam Toxicol ; 105(5): 685-691, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33067667

RESUMO

Owls are predators that perform important ecological functions. There are several threats to owl conservation such as the bioaccumulation of chemicals through environmental contamination. The high probability of bioaccumulation in these animals is related to their role as predators and high trophic positions. The objective of this study was to quantify four elements (cadmium, chromium, nickel, and lead) as the biomarkers of environmental exposure in owls. To this end, we analyzed pellets and feathers of different owl species. These matrices were contaminated with all four elements, with chromium most commonly detected. Chromium and nickel were found in the pellets in all 10 months of the study, and May was the month with the highest concentrations of all the elements. Tyto furcata appears to bioaccumulate more elements in its feathers than Megascops spp. and Athene cunicularia. Our findings showed bioaccumulation of these four elements in owls and their environment.


Assuntos
Monitoramento Biológico/métodos , Poluição Ambiental/análise , Plumas/química , Conteúdo Gastrointestinal/química , Metais Pesados/análise , Estrigiformes/crescimento & desenvolvimento , Animais , Cádmio/análise , Cromo/análise , Refluxo Laringofaríngeo , Chumbo/análise , Metais Pesados/metabolismo , Níquel/análise
3.
Bull Environ Contam Toxicol ; 105(5): 777-783, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33044567

RESUMO

The capacity of Lemna minor to remediate toxic heavy metals from wastewater is reasonably well documented. In view of the pivotal role of this species in the environmental clean-up, here we evaluated the bioaccumulation potential of L. minor for cadmium (Cd), lead (Pb), and nickel (Ni) through a controlled experiment. L. minor tolerated the metals Cd, Ni, and Pb up to 0.5, 5, and 8 mg/L, respectively, and beyond these concentrations the toxicity symptoms appeared. Bio-concentration factor varied at different concentrations of heavy metals tested. Overall, L. minor showed good phytoremediation potential for all the three tested heavy metals (Cd, Ni, and Pb), though in relative terms it was more effective in extracting Ni and Cd, as compared to Pb, both in single and mixed concentrations. In view of the growing pollution in Kashmir Himalayan aquatic habitats the phytoremediation by invasive species such as L. minor promises to be one of the best choices than other native plants for cleaning up of polluted soils/water because of its fast growth rate, high abundance, easy handling, and wide distribution in Kashmir Himalayan aquatic ecosystems.


Assuntos
Organismos Aquáticos/metabolismo , Araceae/metabolismo , Bioacumulação , Metais Pesados/metabolismo , Águas Residuárias/química , Organismos Aquáticos/crescimento & desenvolvimento , Araceae/crescimento & desenvolvimento , Biodegradação Ambiental , Cádmio/análise , Cádmio/metabolismo , Ecossistema , Índia , Lagos , Chumbo/análise , Chumbo/metabolismo , Metais Pesados/análise , Níquel/análise , Níquel/metabolismo
4.
Bull Environ Contam Toxicol ; 105(4): 546-552, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32870331

RESUMO

The heavy metals were studied in water, sediments, algae, and various tissues of Glyptosternon reticulatum and Cyprinus carpio from River Swat, Pakistan, using flame atomic absorption spectrophotometer. The Zn, Cu, Pb and Ni were higher in water at sewage site compared to upstream and downstream sites. In sediments, the Ni and Cd were not detected whereas Cu, Pb and Zn were higher at downstream followed by sewage and upstream sites. The Ni and Zn in algae were higher at upstream and sewage sites compared to downstream site whereas Pb and Cd were higher at upstream site compared to sewage and downstream sites and Cu was found same at all the three sites. The heavy metals (Zn > Cu > Pb and Ni) in tissues (liver > gills > skin > muscles) of G. reticulatum was higher than in C. carpio. This study recommends the proper monitoring of River Swat in order to save its water and inhabitant aquatic life.


Assuntos
Carpas/metabolismo , Peixes-Gato/metabolismo , Sedimentos Geológicos/análise , Metais Pesados/metabolismo , Rios/química , Spirogyra/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Metais Pesados/análise , Paquistão , Especificidade da Espécie , Distribuição Tecidual , Poluentes Químicos da Água/análise
5.
Chemosphere ; 258: 127342, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947679

RESUMO

Environmental contaminations by potentially toxic metals (PTMs) are associated with energy exploitation and present a significant problem in urban areas due to their impacts on human health. The PTMs status in Urumqi total environment inevitably impacted by extensive development of coal and oil industries has been lack of understanding comprehensively. A series of PTMs (As, Ba, Ce, Co, Cr, Cu, Ga, La, Mn, Ni, Pb, Rb, Sr, Th, U, V, Y, Zn, Zr) in the soil-dust-plant (foliage of Ulmus pumila L.) system of Urumqi (NW China) were screened by XRF and ICPMS. Multivariate statistics, risk models, GIS-based geostatistics, Positive Matrix Factorization (PMF) receptor modelling and blood lead levels of 0-6 aged children evaluated by IEUBK model are used to determine the priority pollutants, sources and health effects of the investigated elements. The spatial distribution of PTMs in soil-dust-plant system significantly coincides with coal combustion, traffic emission, and industrial activity. Although all PTM toxicants in soil, dust and tree foliage show some effects, the priority contaminants are observed for Cu, Pb and Zn as single element. The total carcinogenic and non-carcinogenic risks from PTMs are beyond the tolerance range of 0-6 year's old children, and the dust (TCR = 1.07E-04) PTMs pose approximatively equivalent carcinogenic risk to soil PTMs (TCT = 1.09E-04). The predicted BLLs (75-83 µ g·L-1) of 1-2 years children are most strongly influenced by Pb in soil and dust, and therefore more attention should be focused on sources of Pb to support the primary health care of the toddlers in Urumqi.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Metais Pesados/sangue , Poluentes do Solo/sangue , Carcinógenos , China , Poeira/análise , Monitoramento Ambiental , Poluentes Ambientais , Poluição Ambiental/estatística & dados numéricos , Substâncias Perigosas , Humanos , Indústrias , Chumbo/sangue , Metais Pesados/análise , Metais Pesados/metabolismo , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo
6.
Bull Environ Contam Toxicol ; 105(4): 538-545, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32968836

RESUMO

In the present study, heavy metals (Cd, Cu, Pb, and Zn) level in the water, sediment, and crabs were analyzed from Noyyal and Chinnar Rivers of the Western Ghats in Tamil Nadu, India. Based on our results, Noyyal River is considered as polluted environment due to the discharge of contaminants by various anthropogenic activities, whereas, Chinnar River maintained as unpolluted one due to its tributary nature of Noyyal River located in Western Ghats hills. The results showed that the heavy metals in water and sediments were higher in Noyyal River. Also, the level of bioaccumulation of studied metals and biochemical constituents were higher in the crab Spiralothelphusa hydrodroma sampled from Noyyal River than Barytelphusa cunicularis collected from Chinnar River. The present findings revealed that the crab sampled from Noyyal River had elevated heavy metals which lead to a significant increase in biochemical constituents to overcome the stress.


Assuntos
Braquiúros/metabolismo , Exposição Ambiental , Sedimentos Geológicos/análise , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , Monitoramento Ambiental , Feminino , Índia , Masculino , Rios/química , Especificidade da Espécie , Inquéritos e Questionários , Poluição Química da Água
7.
Bull Environ Contam Toxicol ; 105(4): 559-564, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32974765

RESUMO

In this work, we propose to evaluate the effect of agriculture intensification under greenhouses on the biochemical and transcriptomic responses of the earthworms Eisenia andrei. This work was conducted on two sites in Téboulba and Sahline (Monastir governorate) and a control site in an experimental plot that is undergoing organic farming. For this purpose, the earthworms Eisenia andrei were exposed to the soils during 7 and 14 days. The physicochemical properties of the soils were analyzed. The biochemical biomarkers of metallothioneins (MTs) and malondialdehyde (MDA) accumulations were also assessed. Moreover, the gene expression level of the MTs was analyzed. The results of our study revealed a significant trace element accumulation accompanied by a high level of MDA and MT proteins. Moreover, a significant expression of the MT gene was observed in earthworms exposed to the soils from Sahline and Téboulba. Hence, this work reveals that intensive agriculture can affect the biological responses of earthworms and consequently, the soil's biofertility.


Assuntos
Agricultura , Biomarcadores Ambientais/fisiologia , Metais Pesados/metabolismo , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/metabolismo , Solo/química , Agricultura/métodos , Animais , Expressão Gênica/efeitos dos fármacos , Malondialdeído/metabolismo , Metalotioneína/metabolismo , Oligoquetos/genética , Oligoquetos/metabolismo , Tunísia
8.
Chemosphere ; 261: 127748, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32738713

RESUMO

Data about the toxicological interactions of MPs and heavy metals in biota is limited, particularly in fish early life stages. This study aimed to evaluate the toxicological effects of MPs and copper (Cu), alone or combined, in zebrafish early life stages. Embryos were exposed from 2 until 96-h post-fertilization (hpf) to MPs (2 mg/L), three sub-lethal concentrations of Cu (15, 60 and 125 µg/L) and binary mixtures containing Cu and MPs (Cu15+MPs, Cu60+MPs, Cu125+MPs). Lethal and sub-lethal parameters, histopathological changes, biochemical biomarkers, gene expression and behavior were assessed. Our findings showed that Cu and Cu + MPs decreased embryos survival and hatching rate. Increased ROS levels were observed in larvae exposed to the two lowest Cu and Cu + MPs groups, suggesting an induction of oxidative stress. An increased CAT and GPx activities were observed in Cu and Cu + MPs, implying a response of the antioxidant defense system to overcome the metal and MPs stress. The sod1 expression was downregulated in all Cu groups and in the two highest Cu + MPs exposed groups. AChE was significantly inhibited in Cu and Cu + MPs groups, indicating neurotoxicity. A disruption of avoidance and social behaviors were also noticed in the Cu125 and Cu125+MPs exposed larvae. Evidences of Cu-toxicity modulation by MPs were observed in some endpoints. Overall, the findings of this study highlight that Cu alone or co-exposed with MPs lead to oxidative stress, neurotoxicity and ultimately behavioral alterations in early life stages of zebrafish, while MPs alone do not produce significant effects on zebrafish larvae.


Assuntos
Cobre/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Metais Pesados , Microplásticos/toxicidade , Peixe-Zebra/fisiologia , Animais , Antioxidantes/metabolismo , Comportamento Animal/efeitos dos fármacos , Biomarcadores/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Metais Pesados/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Plásticos/metabolismo , Taxa de Sobrevida , Poluentes Químicos da Água/toxicidade
9.
Ecotoxicol Environ Saf ; 204: 111020, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32810706

RESUMO

Over the past 30 years, the ever-rising demands of the modern and growing population have led to the rapid development of agricultural and industrial sectors worldwide. However, this expansion has exposed the environment to various pollutants including heavy metal (HM)s. Almost all HMs are serious toxicants and can pose serious health risks to living organisms in addition to their bioaccumulative and non-biodegradable nature. Different techniques have been developed to restore the ecological functions of the HM-contaminated soil (HMCS). However, the major downfalls of the commonly used remediation technologies are the generation of secondary wastes, high operating costs, and high energy consumption. Phytoremediation is a prominent approach that is more innocuous than the existing remediation approaches. Some microbes-plant interactions enhance the bioremediation process, with heavy metal resistant-plant growth promoting bacteria (HMRPGPB) being widely used to assist phytoremediation of HMs. However, the most common of all major microbial assisted-phytoremediation disturbances is that the HM-contaminated soil is generally deficient in nutrients and cannot sustain the rapid growth of the applied HMRPGPB. In this case, biochar has recently been approved as a potential carrier of microbial agents. The biochar-HMRPGPB-plant association could provide a promising green approach to remediate HM-polluted sites. Therefore, this review addresses the mechanisms through which biochar and HMRPGPB can enhance phytoremediation. This knowledge of biochar-HMRPGPB-plant interactions is significant with respect to sustainable management of the HM-polluted environment in terms of both ecology and economy, and it offers the possibility of further development of new green technologies.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Carvão Vegetal/farmacologia , Embriófitas/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Desenvolvimento Vegetal/fisiologia , Solo/química
10.
Ecotoxicol Environ Saf ; 202: 110906, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800241

RESUMO

The nonsteroidal anti-inflammatory drug diclofenac (DCF) is considered a contaminant of emerging concern. DCF can co-exist with heavy metals in aquatic environments, causing unexpected risks to aquatic organisms. This study aimed to assess the combined effects of DCF and cadmium (Cd) at environmentally relevant concentrations on the bioconcentration and status of oxidative stress and detoxification in Chironomus riparius larvae. The larvae were exposed to DCF (2 and 20 µg L-1) and Cd (5 and 50 µg L-1) alone or in mixtures for 48 h. The combined exposure to DCF and Cd was found to reciprocally facilitate the accumulation of each compound in larvae compared with single exposures. As indicated by the antioxidant enzyme activities, reduced glutathione levels, and malondialdehyde contents, the low concentration of the mixture (2 µg L-1 DCF + 5 µg L-1 Cd) did not alter the oxidative stress status in larvae, while the high concentration of the mixture (20 µg L-1 DCF + 50 µg L-1 Cd) induced stronger oxidative damage to larvae compared with single exposures. The expression levels of eight genes (CuZnSOD, MnSOD, CAT, GSTd3, GSTe1, GSTs4, CYP4G, and CYP9AT2) significantly decreased due to the high concentration of the mixture compared with single exposures in most cases. Overall, the results suggest that the mixture of DCF and Cd might exert greater ecological risks to aquatic insects compared with their individual compounds.


Assuntos
Cádmio/toxicidade , Chironomidae/fisiologia , Diclofenaco/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Cádmio/metabolismo , Chironomidae/efeitos dos fármacos , Diclofenaco/metabolismo , Inativação Metabólica/efeitos dos fármacos , Larva/efeitos dos fármacos , Malondialdeído/metabolismo , Metais Pesados/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
11.
Ecotoxicol Environ Saf ; 202: 110954, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800228

RESUMO

Current study aims to determine difference in metal accumulation pattern in muscle of Liza parsia (pelagic, omnivore), Amblypharyngodon mola (surface feeder, herbivore) and Mystus gulio (benthic, carnivore) depending on their niche and feeding habit and how it affects the endogenous antioxidants and glucose metabolism in fish muscle. Fishes were collected from Malancha, Diamond Harbour and Chandanpiri, West Bengal, India. Concentrations of lead, zinc, cadmium, chromium were measured in water, sediment and fish muscle. Metal pollution index (MPI) and bioconcentration factor (BCF) was calculated to evaluate the ability of fish to accumulate specific metals in muscle tissue from the aquatic environment. Metal concentrations were found significantly higher (P < 0.05) in water, sediment, fish muscles from Malancha than Chandanpiri and Diamond Harbour. L. parsia (MPI: 0.4-1.6) showed highest metal deposition in their muscle followed by A. mola (MPI: 0.37-1.38) and M. gulio (MPI: 0.2-1.2). Malondealdehyde, superoxide dismutase, catalase, glutathione S transferase, glutathione reductase and cortisol levels increased in case of L. parsia from Malancha and Chandanpiri. Succinate dehydrogenase, lactate dehydrogenase, Ca+2 ATPase and cytochrome C oxidase levels were significantly (P < 0.05) lower at Malancha and Chandanpiri than Diamond Harbour. Heat shock protein (HSP70) expression was significantly (P < 0.05) higher in all fish species at Malancha followed by Chandanpiri and Diamond Harbour. Glucose, glycogen, hexokinase, phosphofructokinase and glycogen phosphorylase levels varied between sites and selected fish species. Serum cortisol level was measured and found to be the highest in L. parsia from Malancha (2.94 ± 0.12 ng/ml) and the lowest in M. gulio from Diamond Harbour (0.7 ± 0.05 ng/ml). The results indicate that metal toxicity alters antioxidant levels, oxidative status and energy production in fish in species specific manner. Our results also indicate that Mystus has the highest degree of adaptability in response to metal toxicity possibly due to its specific food habit and niche position. Therefore, it can be concluded that maintenance of oxidative and metabolic status to combat metal-induced oxidative load will be helpful for the fishes to acquire better resistance under such eco-physiological stress. Alteration of niche and interactive segregation in aquatic organism may be one of the key modulator of resistance against such stress.


Assuntos
Antioxidantes/metabolismo , Cyprinidae/metabolismo , Comportamento Alimentar/fisiologia , Glucose/metabolismo , Metais Pesados/toxicidade , Músculos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Cyprinidae/fisiologia , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Índia , Metais Pesados/metabolismo , Músculos/enzimologia , Músculos/metabolismo , Oxirredução , Especificidade da Espécie , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/metabolismo
12.
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
13.
PLoS One ; 15(7): e0236943, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735612

RESUMO

Halophyte Lobularia maritima LmSAP encodes an A20AN1 zinc-finger stress-associated protein which expression is up-regulated by abiotic stresses and heavy metals in transgenic tobacco. To deepen our understanding of LmSAP function, we isolated a 1,147 bp genomic fragment upstream of LmSAP coding sequence designated as PrLmSAP. In silico analyses of PrLmSAP revealed the presence of consensus CAAT and TATA boxes and cis-regulatory elements required for abiotic stress, phytohormones, pathogen, and wound responses, and also for tissue-specific expression. The PrLmSAP sequence was fused to the ß-glucuronidase (gusA) reporter gene and transferred to rice. Histochemical GUS staining showed a pattern of tissue-specific expression in transgenic rice, with staining observed in roots, coleoptiles, leaves, stems and floral organs but not in seeds or in the root elongation zone. Wounding strongly stimulated GUS accumulation in leaves and stems. Interestingly, we observed a high stimulation of the promoter activity when rice seedlings were exposed to NaCl, PEG, ABA, MeJA, GA, cold, and heavy metals (Al3+, Cd2+, Cu2+ and Zn2+). These results suggest that the LmSAP promoter can be a convenient tool for stress-inducible gene expression and is a potential candidate for crop genetic engineering.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Regiões Promotoras Genéticas , Plantas Tolerantes a Sal/genética , Estresse Fisiológico/genética , Dedos de Zinco/genética , Produtos Agrícolas/genética , Engenharia Genética , Glucuronidase/metabolismo , Metais Pesados/metabolismo , Especificidade de Órgãos , Oryza/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tabaco/genética
14.
Ecotoxicol Environ Saf ; 204: 111098, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798749

RESUMO

Cadmium (Cd) is a detrimental element that can be toxic to plants. The physiological and biochemical responses of plants to Cd stress have been extensively studied, but the molecular mechanisms remain unclear. The present study showed that Cd severely inhibited the growth of roots and shoots and reduced plant biomass of mung bean seedlings. To further investigate the gene profiles and molecular processes in response Cd stress, transcriptome analyses of mung bean roots exposed to 100 µM Cd for 1, 5, and 9 days were performed. Cd treatment significantly decreased global gene expression levels at 5 and 9 d compared with the control. A total of 6737, 10279, and 9672 differentially expressed genes (DEGs) were identified in the 1-, 5-, and 9-day Cd-treated root tissues compared with the controls, respectively. Based on the analysis of DEG function annotation and enrichment, a pattern of mung bean roots response to Cd stress was proposed. The processes detoxification and antioxidative defense were involved in the early response of mung bean roots to Cd. Cd stress downregulated the expressions of a series of genes involved in cell wall biosynthesis, cell division, DNA replication and repair, and photosynthesis, while genes involved in signal transduction and regulation, transporters, secondary metabolisms, defense systems, and mitochondrial processes were upregulated in response to Cd, which might be contributed to the improvement of plant tolerance. Our results provide some novel insights into the molecular processes for growth and adaption of mung bean roots in response to Cd and many candidate genes for further biotechnological manipulations to improve plant tolerance to heavy metals.


Assuntos
Cádmio/toxicidade , Poluentes do Solo/toxicidade , Aclimatação , Adaptação Fisiológica , Antioxidantes/metabolismo , Cádmio/metabolismo , Poluição Ambiental , Fabaceae/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metais Pesados/metabolismo , Raízes de Plantas/metabolismo , Plântula/metabolismo , Poluentes do Solo/metabolismo , Transcriptoma , Vigna/metabolismo
15.
Ecotoxicology ; 29(9): 1522-1537, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32710163

RESUMO

One of the major problems affecting the ecosystem health is the exposure of heavy metals due to anthropogenic activities. These exposures may induce toxiogenetic damage and carcinogenesis in aquatic organism. DNA damage biomarkers for fish species detect genotoxic parameters for ecological risk assessment. In the present study, the effect of heavy metals (Cr, Cd, Cu, Fe and Mn) on DNA damage and oxidative stress of Clarias gariepinus was examined by Comet assay at Reference site and two different sampling sites of the Orontes River. Moreover, the relationship between DNA damage and physiological response to oxidative stress caused in C. gariepinus was investigated by sampling seasonal water and fish samples for one year. In this study, Cr, Cd and Cu in water column of Orontes River and the concentrations of Fe and Mn in liver tissue of C. gariepinus were highly exceed the maximum permissible limit set by EPA (1999, 2016) WHO (1989) and TEG (2012) that can cause adverse effects on environment health. SOD activities in liver tissues were significantly higher than those in muscle tissues. SOD, CAT activity and MDA levels of both Site 1 and Site 2 at Orontes River were higher than those of the Reference site. In result of the COMET analysis, the highest levels of DNA damage were found at gill and liver tissues in Site 2 (17.746 ± 1.072% T-DNA; 16.014 ± 0.710% T-DNA respectively) at Orontes river. A higher level of DNA damage in gill cells compared to liver cells was observed in all regions of the Orontes River. In Principal component analysis (PCA), the heavy metals Cd, Cr and Cu (in the water column) and MDA in liver and muscle revealed strong contribution to the observed DNA damage that were scattered opposite to each other's along the principal components. Moreover, correlations between parameters revealed a positive significant relationship between Cd, Cr and Cu in water and DNA damage levels in C. gariepinus. Pearson correlation analysis detected a positive relationship between MDA, CAT and SOD and DNA damage levels in African catfish. Consequently, this study exposed genotoxic damage and oxidative stress of C. gariepinus due to metal pollution in Orontes River and lead to the better understanding of genotoxicty, oxidative stress and heavy metal relationships.


Assuntos
Peixes-Gato/fisiologia , Monitoramento Ambiental , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Metais Pesados/toxicidade , Estresse Oxidativo , Rios , Poluentes Químicos da Água/toxicidade
16.
Ecotoxicol Environ Saf ; 203: 111017, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678748

RESUMO

In this study, the effect of two metal-immobilizing bacterial strains, Serratia liquefaciens CL-1 and Bacillus thuringiensis X30, on the availability of Cd and Pb and the metal accumulation in potato tubers, as well as the underlying mechanisms in metal-contaminated soils were characterized. Moreover, the impacts of the strains on metal immobilization, pH, and NH4+ concentration in metal-contaminated soil solutions were evaluated. Strains CL-1 and X30 increased tuber dry weight by 46% and 40%, reduced tuber Cd and Pb contents by 68-83% and 42-47%, and decreased the Cd and Pb translocation factors by 61-70% and 30-34%, respectively, compared to the controls. Strains CL-1 and X30 decreased the available Cd and Pb contents by 52-67% and 30-44% and increased the NH4+ content by 55% and 31%, pH, urease activity by 70% and 41%, and relative abundance of ureC gene copies by 37% and 20% in the rhizosphere soils, respectively, compared with the controls. Reduced Cd and Pb concentrations and increased pH and NH4+ concentration were found in the bacteria-inoculated soil solution compared to the controls. These results suggested that the strains reduced tuber metal uptake through decreasing the metal availability and increasing the pH, ureC gene relative abundance and urease activity as well as decreasing the metal translocation from the leaves to tubers. These results may provide an effective metal-immobilizing bacteria (especially strain CL-1)-enhanced approach to reduce metal uptake of potato tubers in metal-polluted soils.


Assuntos
Bacillus thuringiensis/metabolismo , Metais Pesados/metabolismo , Serratia liquefaciens/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Urease/metabolismo , Biodegradação Ambiental , Biomassa , Cádmio/metabolismo , Chumbo/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Rizosfera , Solo/química , Poluentes do Solo/análise , Solanum tuberosum/metabolismo , Especificidade da Espécie
17.
PLoS One ; 15(7): e0236313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706781

RESUMO

The impacts of urbanization, such as urban heat island (UHI) and nutrient loads, can influence tree function through altered physiology and metabolism and stress response, which has implications for urban forest health in cities across the world. Our goal was to compare growth-stimulating and stress-mitigating acclimation patterns of red maple (Acer rubrum) trees in deciduous forests embedded in a small (Newark, DE, US) and a large (Philadelphia, PA, US) city. The study was conducted in a long-term urban forest network on seventy-nine mature red maple trees spanning ten forests across Newark and Philadelphia. We hypothesized that red maples in Philadelphia forests compared to Newark forests will be healthier and more acclimated to warmer temperatures, elevated CO2 concentrations and reactive nitrogen (Nr) deposition, and higher nutrient/heavy metal loads. Therefore, these red maples will have higher foliar pigments, nutrients, and stress-indicating elements, enriched δ15N isotopes and increased free polyamines and amino acids to support a growth-stimulating and stress-induced response to urbanization. Our results indicate red maples are potentially growth-stimulated and stress-acclimated in Philadelphia forests experiencing a greater magnitude of urban intensity. Red maples in Philadelphia forests contained higher concentrations of foliar chlorophyll, %N, δ15N, and nutrients than those in Newark forests. Similarly, lower foliar magnesium and manganese, and higher foliar zinc, cadmium, lead, and aluminum reflected the difference in soil biogeochemistry in Philadelphia forests. Accumulation patterns of foliar free amino acids, polyamines, phosphorous, and potassium ions in red maples in Philadelphia forests shows a reallocation in cellular metabolism and nutrient uptake pathways responsible for physiological acclimation. Our results suggest the approach used here can serve as a model for investigating 'plant physiology' and the use of urban trees as a biomonitor of the impacts of 'urban pollution' on urban forests. The results suggest that cellular oxidative stress in trees caused by pollutant uptake is mitigated by the accumulation of free amino acids, polyamines, and nutrients in a larger city. Our study provides a framework for determining whether trees respond to complex urban environments through stress memory and/or acclimation.


Assuntos
Aclimatação , Acer/fisiologia , Parques Recreativos , Árvores/fisiologia , Clorofila/metabolismo , Delaware , Florestas , Temperatura Alta , Metais Pesados/análise , Metais Pesados/metabolismo , Nitrogênio/metabolismo , Philadelphia , Folhas de Planta/metabolismo , Solo/química , Urbanização
18.
Bull Environ Contam Toxicol ; 105(3): 411-421, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32725326

RESUMO

Phytoremediation is an ecologically and economically feasible technique to remove heavy metal from soil. The aim of the study was to examine cadmium (Cd) toxicity and phytoremediation aptitude of Brassica juncea. In the present study, plants survived when exposed to different levels of Cd (0, 25, 50 and 100 mg/kg soil) and accumulated a large amount of Cd in its root and shoot. Translocation factor (TF) of Cd from root to shoot was > 1 at both 45 and 60-day stage of growth suggesting that B. juncea is a hyperaccumulator and strong candidate for phytoextraction of Cd. Alongside, Cd impaired photolysis of water, PSII activity, nutrient uptake, photosynthesis and sugar accumulation in the plant. Cd-generated oxidative stress restricts the growth of B. juncea. The toxic effect of Cd was more pronounced at 45-day stage of growth signifying the drifting of plant towards acquirement of exclusion strategy.


Assuntos
Biodegradação Ambiental , Cádmio/metabolismo , Mostardeira/metabolismo , Poluentes do Solo/metabolismo , Cádmio/análise , Metabolismo dos Carboidratos , Gases , Metais Pesados/metabolismo , Mostardeira/efeitos dos fármacos , Mostardeira/crescimento & desenvolvimento , Oxirredução , Solo , Poluentes do Solo/análise
19.
Chemosphere ; 259: 127497, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32650168

RESUMO

Heavy metal pollution is an increasingly serious problem in agricultural ecosystems. Zinc accumulation in the food chain may harm the physiological functions of organisms, including herbivorous and predatory insects. Its effects on development and reproduction in Harmonia axyridis are largely unknown. In this study, five Zn solutions (25, 50, 100, and 150 mg/kg) plus control (0 mg/kg) were used to treat broad beans and to water the resulting seedlings. Aphids fed on these seedlings were eaten by H. axyridis ladybugs. Zn accumulation was found at all three trophic levels. Compared with the control group, ladybugs in the 25, 50, and 100 mg/kg groups had significantly reduced weight gain from the 4th instar to adulthood. Pupae and larvae (instars 1-4) in the 150 mg/kg group had the lowest survival of any group; pupal mortality in the 100 mg/kg group was significantly higher than that in the control group. Under Zn stress, female adults had inhibited expression of Vg1, Vg2 and VgR, reducing egg production and hatchability. Zn thus negatively affected their fertility. These results provide a theoretical basis for future exploration of soil heavy metal pollution impacts in ecosystems.


Assuntos
Afídeos/química , Besouros/efeitos dos fármacos , Poluentes Ambientais/farmacologia , Fertilidade/efeitos dos fármacos , Cadeia Alimentar , Zinco/farmacologia , Animais , Afídeos/metabolismo , Besouros/crescimento & desenvolvimento , Besouros/metabolismo , Besouros/fisiologia , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Metais Pesados/metabolismo , Metais Pesados/farmacologia , Plantas Comestíveis/química , Plantas Comestíveis/parasitologia , Reprodução/efeitos dos fármacos , Zinco/metabolismo
20.
Ecotoxicol Environ Saf ; 200: 110776, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32474243

RESUMO

Over the past decades, titanium dioxide nanoparticles (n-TiO2) have been extensively used in several industrial applications and the manufacture of novel consumer products. Although strict regulations have been put in place to limit their release into the aquatic environment, these nanoparticles can still be found at elevated levels within the environment, which can result in toxic effects on exposed organisms and has possible implications in term of public health. Bivalve mollusks are a unique and ideal group of shellfish for the study and monitoring the aquatic pollution by n-TiO2 because of their filter-feeding behaviour and ability to accumulate toxicants in their tissues. In these animals, exposure to n-TiO2 leads to oxidative stress, immunotoxicity, neurotoxicity, and genotoxicity, as well as behavioral and physiological changes. This review summarizes the uptake, accumulation, and fate of n-TiO2 in aquatic environments and the possible interactions between n-TiO2 and other contaminants such as heavy metals and organic pollutants. Moreover, the toxicological impacts and mechanisms of action are discussed for a wide range of bivalve mollusks. This data underlines the pressing need for additional knowledge and future research plans for the development of control strategies to mitigate the release of n-TiO2 to the aquatic environment to prevent the toxicological impacts on bivalves and protect public health.


Assuntos
Bivalves/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bioacumulação , Bivalves/genética , Bivalves/metabolismo , Dano ao DNA , Ecotoxicologia , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Nanopartículas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Frutos do Mar , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
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