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1.
Salud pública Méx ; 62(3): 262-269, May.-Jun. 2020. tab, graf
Article in English | LILACS | ID: biblio-1377312

ABSTRACT

Abstract: Objective: To describe interindividual metabolism variations and sociodemographic characteristics associated to urinary arsenic, and to estimate the arsenic contamination in water from urinary total arsenic (TAs). Materials and methods: Women (n=1 028) from northern Mexico were interviewed about their sociodemographic characteristics and their urinary concentrations of arsenic species were measured by liquid chromatography. Inorganic arsenic (iAs) in water was estimated from urinary TAs. Results: Women were 20-88 years old. TAs in urine ranged from p10=3.41 to p90=56.93 μg/L; 74% of women had levels >6.4 μg/L. iAs in water varied from p10=3.04 to p90=202.12 μg/L; 65% of women had concentrations >10 μg/L, and 41%, concentrations >25 μg/L. Large variations in iAs metabolism were observed. TAs was significantly negatively associated with age and schooling, and positively with the state of residence. Conclusion: Exposure to iAs is an environmental problem in Mexico. Individual variations in metabolism are a challenge to design prevention and control programs.


Resumen: Objetivo: Describir las variaciones interindividuales del metabolismo y las características sociodemográficas asociadas con el arsénico urinario, así como estimar su contaminación en el agua. Material y métodos. Se entrevistó a 1 028 mujeres del norte de México; por cromatografía de líquidos se midieron los metabolitos urinarios de arsénico y, a partir de ellos, se estimó la concentración en agua. Resultados: Las mujeres tuvieron 20-88 años. El arsénico urinario varió de p10=3.41 a p90=56.93 μg/L; 74% de las mujeres tuvieron niveles >6.4 μg/L. El arsénico en agua varió de p10=3.04 a p90=202.12 μg/L; 65% de las mujeres tenían concentraciones >10 μg/L, y 41%, >25 μg/L. Se observaron amplias variaciones en el metabolismo del arsénico. El arsénico urinario se asoció negativamente con la edad y escolaridad, y positivamente con el estado de residencia. Conclusión: La exposición a arsénico es un problema ambiental en México. Las variaciones individuales en su metabolismo son un desafío para diseñar programas de prevención y control.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Young Adult , Arsenic/urine , Water Pollutants, Chemical/analysis , Environmental Exposure , Herbicides/urine , Arsenates/urine , Arsenates/analysis , Arsenates/metabolism , Arsenic/analysis , Arsenic/metabolism , Arsenicals/urine , Arsenicals/analysis , Arsenicals/metabolism , Socioeconomic Factors , Cacodylic Acid , Case-Control Studies , Chromatography, Liquid , Herbicides/analysis , Herbicides/metabolism , Mexico
2.
Braz. arch. biol. technol ; 63: e20180571, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132192

ABSTRACT

Abstract Rice (Oryza sativa L.) is one of the most important crops in the world, and it is considered the primary source of nutritional layout in developing countries in Asia. The glutathione S-transferases (GSTs) superfamily confers to rice protection against biotic and abiotic stress, and herbicide resistance. However, the three-dimensional structure of a GST Tau class, is unsolved. The objectives of this work were to develop a reliable comparative model for the s-transferase glutathione class Tau 4 from rice, and simulate docking interactions, against herbicides bentazon and metsulfuron. Results showed that the predicted model is reliable and has structural quality. Ramachandran plot set 91.9% of the residues in the most favored regions. All complexes showed negative binding energies values; and metsulfuron docked to the glutathione tripeptide, and it represents a possible insilico evidence of glutathione conjugation with this herbicide.


Subject(s)
Oryza/enzymology , Stress, Physiological , Glutathione Transferase/metabolism , Herbicides/metabolism , Oryza/drug effects , Inactivation, Metabolic
3.
Rev. argent. microbiol ; 49(2): 189-196, jun. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-957998

ABSTRACT

El paraquat es un herbicida utilizado ampliamente en la agricultura. Debido a su gran distribución y uso inadecuado, representa un problema grave de contaminación del suelo y el agua. Se ha encontrado que los hongos de la podredumbre blanca son capaces de degradar compuestos contaminantes que poseen estructuras similares a la lignina, como es el caso del paraquat. En el presente trabajo se evaluó la degradación de este herbicida y su efecto en la producción de enzimas ligninolíticas por parte de algunos hongos de la podredumbre blanca aislados del sur de México. Seis cepas fúngicas mostraron tolerancia al herbicida durante el cultivo en medio sólido. Tres de las 6 cepas evaluadas, correspondientes a las especies Polyporus tricholoma, Cilindrobasidium laeve y Deconica citrispora, mostraron niveles de degradación del 32, el 26 y el 47%, en ese orden, a los 12 días de cultivo en presencia del xenobiótico. Se detectó un incremento en las actividades de las enzimas lacasa y Mn-peroxidasa en las cepas que presentaron el mayor porcentaje de degradación, probablemente asociado a la disminución del herbicida. Adicionalmente, se realizaron ensayos con extractos enzimáticos procedentes del medio de cultivo extracelular de las 2 cepas que presentaron mayor degradación. Después de 24 h de incubación, se obtuvo una degradación del 49% del paraquat inicial con los extractos de D. citrispora. Los resultados obtenidos indican que la degradación del herbicida estaría asociada a la presencia de enzimas extracelulares en los hongos de la podredumbre blanca. En este trabajo se muestran las primeras evidencias del potencial de biodegradación de diferentes especies de hongos de la pudrición blanca.


Paraquat is a widely used herbicide in agriculture. Its inappropriate use and wide distribution represents a serious pollution problem for soil and water. White rot fungi are capable of degrading pollutants having a similar structure to that of lignin, such as paraquat. This study evaluated the degradation effect of paraquat on the production of ligninolytic enzymes by white rot fungi isolated from the South of Mexico. Six fungal strains showed tolerance to the herbicide in solid culture. Three of the six evaluated strains showed levels of degradation of 32, 26 and 47% (Polyporus tricholoma, Cilindrobasidium laeve and Deconica citrispora, respectively) after twelve days of cultivation in the presence of the xenobiotic. An increase in laccase and manganese peroxidase (MnP) activities was detected in the strains showing the highest percentage of degradation. Experiments were done with enzyme extracts from the extracellular medium with the two strains showing more degradation potential and enzyme production. After 24 hours of incubation, a degradation of 49% of the initial paraquat concentration was observed for D. citrispora. These results suggest that paraquat degradation can be attributed to the presence of extracellular enzymes from white rot fungi. In this work the first evidence of the biodegradation potential of D. citrispora and Cilindrobasidium leave is shown.


Subject(s)
Paraquat , Peroxidases , Fungi , Herbicides , Paraquat/metabolism , Biodegradation, Environmental , Laccase , Fungi/enzymology , Herbicides/metabolism , Lignin , Mexico
4.
Braz. j. microbiol ; 48(1): 101-108, Jan.-Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-839340

ABSTRACT

Abstract Production of a bioherbicide for biological control of weeds requires a series of steps, from selection of a suitable microbial strain to final formulation. Thus, this study aimed to select fungi for production of secondary metabolites with herbicidal activity using biological resources of the Brazilian Pampa biome. Phytopathogenic fungi were isolated from infected tissues of weeds in the Pampa biome. A liquid synthetic culture medium was used for production of metabolites. The phytotoxicity of fungal metabolites was assessed via biological tests using the plant Cucumis sativus L., and the most promising strain was identified by molecular analysis. Thirty-nine fungi were isolated, and 28 presented some phytotoxic symptoms against the target plant. Fungus VP51 belonging to the genus Diaporthe showed the most pronounced herbicidal activity. The Brazilian Pampa biome is a potential resource for the development of new and sustainable chemical compounds for modern agriculture.


Subject(s)
Biological Products/metabolism , Fungi/metabolism , Herbicides/metabolism , Phylogeny , Brazil , RNA, Ribosomal, 5.8S/genetics , DNA, Intergenic , Plant Weeds/microbiology , Fermentation , Fungi/isolation & purification , Fungi/classification , Fungi/genetics
5.
Braz. j. microbiol ; 46(2): 425-432, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749712

ABSTRACT

The strain JPL-2, capable of degrading fenoxaprop-P-ethyl (FE), was isolated from the soil of a wheat field and identified as Rhodococcus ruber. This strain could utilize FE as its sole carbon source and degrade 94.6% of 100 mg L−1 FE in 54 h. Strain JPL-2 could also degrade other aryloxyphenoxy propanoate (AOPP) herbicides. The initial step of the degradation pathway is to hydrolyze the carboxylic acid ester bond. A novel esterase gene feh, encoding the FE-hydrolyzing carboxylesterase (FeH) responsible for this initial step, was cloned from strain JPL-2. Its molecular mass was approximately 39 kDa, and the catalytic efficiency of FeH followed the order of FE > quizalofop-P-ethyl > clodinafop-propargyl > cyhalofop-butyl > fluazifop-P-butyl > haloxyfop-P-methyl > diclofop-methy, which indicated that the chain length of the alcohol moiety strongly affected the hydrolysis activity of the FeH toward AOPP herbicides.


Subject(s)
Carboxylesterase/genetics , Carboxylesterase/metabolism , Herbicides/metabolism , Oxazoles/metabolism , Propionates/metabolism , Rhodococcus/isolation & purification , Rhodococcus/metabolism , Biotransformation , Cloning, Molecular , Cluster Analysis , Carboxylesterase/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Molecular Weight , Phylogeny , /genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Rhodococcus/enzymology , Rhodococcus/genetics , Sequence Analysis, DNA , Soil Microbiology , Substrate Specificity , Triticum/growth & development
6.
Braz. j. microbiol ; 46(2): 433-441, Apr-Jun/2015. graf
Article in English | LILACS | ID: lil-749723

ABSTRACT

An indigenous bacterial strain capable of utilizing 2,4-dichlorophenoxyacetic acid as the sole carbon and energy source was isolated from a soil used for grown wheat with a long-term history of herbicide use in Beijing, China. The strain BJ71 was identified as Cupriavidus campinensis based on its 16S rRNA sequence analysis and morphological, physiological, and biochemical characteristics. The degradation characteristics of strain BJ71 were evaluated. The optimal conditions for 2,4-D degradation were as follows: pH 7.0, 30 °C, 3% (v/v) inoculum size, and an initial 2,4-D concentration of 350 mg L−1. Up to 99.57% of the 2,4-D was degraded under optimal conditions after 6 days of incubation. Strain BJ71 was also able to degrade quizalofop and fluroxypyr. This is the first report of a 2,4-D-degrader containing tfdA gene that can utilize these two herbicides. In a biodegradation experiment, 87.13% and 42.53% of 2,4-D (initial concentration, 350 mg kg−1) was degraded in non-sterile and sterilized soil inoculated with BJ71, respectively, after 14 days. The 2,4-D degradation was more rapid in a soil microcosm including BJ71 than in a soil microcosm without BJ71. These results indicate that strain BJ71 is a potential candidate for the bioremediation of soil contaminated with the herbicide 2,4-D.


Subject(s)
Cupriavidus/isolation & purification , Cupriavidus/metabolism , Herbicides/metabolism , /metabolism , Acetates/metabolism , Bacteriological Techniques , Biotransformation , China , Cluster Analysis , Cupriavidus/genetics , Cupriavidus/physiology , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Molecular Sequence Data , Phylogeny , Propionates/metabolism , Pyridines/metabolism , Quinoxalines/metabolism , /genetics , Sequence Analysis, DNA , Temperature , Time Factors , Triticum
7.
Braz. j. microbiol ; 45(3): 971-975, July-Sept. 2014. graf
Article in English | LILACS | ID: lil-727028

ABSTRACT

This study evaluated the impact of different concentrations of glyphosate (Rondup®) on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC®15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, and 1690 ppm) and cultured in normoxia and anoxia, following their OD560nm every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm) in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p < 0.05). However, these same concentrations favor the planktonic anaerobic growth (p < 0.05). On the other hand, the herbicide favors a slight growth of biofilms in a concentration-dependent manner up to 84.5 ppm (p > 0.05), and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p < 0.05), regardless of concentration. In a concentration-dependent manner, glyphosate interferes with the growth ability of P. aeruginosa ATCC®15442.


Subject(s)
Biofilms/drug effects , Biofilms/growth & development , Glycine/analogs & derivatives , Herbicides/metabolism , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Aerobiosis , Anaerobiosis , Biomass , Glycine/metabolism , Spectrophotometry
8.
Braz. j. microbiol ; 44(4): 1207-1214, Oct.-Dec. 2013. ilus, tab
Article in English | LILACS | ID: lil-705249

ABSTRACT

Fungi have been recently recognized as organisms able to grow in presence of high salt concentration with halophilic and halotolerance properties and their ligninolytic enzyme complex have an unspecific action enabling their use to degradation of a number of xenobiotic compounds. In this work, both the effect of salt and polyols on growth of the basidiomycetes strains, on their ability to produce ligninolytic enzyme and diuron degradation were evaluated. Results showed that the presence of NaCl in the culture medium affected fungal specimens in different ways. Seven out of ten tested strains had growth inhibited by salt while Dacryopinax elegans SXS323, Polyporus sp MCA128 and Datronia stereoides MCA167 fungi exhibited higher biomass production in medium containing 0.5 and 0.6 mol.L-1 of NaCl, suggesting to be halotolerant. Polyols such as glycerol and mannitol added into the culture media improved the biomass and ligninases production by D. elegans but the fungus did not reveal consumption of these polyols from media. This fungus degraded diuron in medium control, in presence of NaCl as well as polyols, produced MnP, LiP and laccase.


Subject(s)
Basidiomycota/enzymology , Basidiomycota/metabolism , Herbicides/metabolism , Oxygenases/metabolism , Sodium Chloride/metabolism , Biomass , Biotransformation , Basidiomycota/drug effects , Basidiomycota/growth & development , Culture Media/chemistry , Diuron/metabolism , Growth Inhibitors/metabolism , Growth Inhibitors/toxicity , Polymers/metabolism , Polymers/toxicity , Sodium Chloride/toxicity
9.
J Environ Biol ; 2008 Mar; 29(2): 175-8
Article in English | IMSEAR | ID: sea-113804

ABSTRACT

In this study, effect of different 2,4 -dichlorophenoxyacetic acid (2,4-D) concentrations (0.0, 9.10(-5), 9.10(-4), 9.10(-3) and 9.10(-2) mM) on growth rate, content of protein and chlorophyll-a in Chlorella vulgaris and Spirulina platensis cells was investigated. The most stimulatory effect on growth rate, protein and pigment ratio of C. vulgaris and S. platensis was observed at 9.10(-4) mM concentrations of 2,4-D. The results show that low concentrations of 2,4-D have hormonal effect due to being a synthetic auxin. Cell number protein and pigment rates were inhibited at 9.10(-2) mM concentration in C. vulgaris. Such parameters were inhibited in S. platensis, both at 9.10(-3) and 9.10(-2) mM 2,4-D concentrations. This is due to herbicidal effect of high concentrations of 2,4-D. S. platensis was found to be more sensitive than S. vulgaris to 2,4-D applications. The use of algae as bio-indicators in herbicide contaminated fresh water habitats, was discussed.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/metabolism , Chlorella vulgaris/cytology , Chlorophyll/metabolism , Dose-Response Relationship, Drug , Fresh Water , Herbicides/metabolism , Kinetics , Nuclear Proteins/metabolism , Pigments, Biological/antagonists & inhibitors , Spirulina/cytology , Water Pollutants, Chemical/metabolism
10.
Article in English | IMSEAR | ID: sea-114181

ABSTRACT

Glyphosate application resulted in a decline in soil pH with consequent increase in soil mycoflora suggesting an indirect relationship. Though the composition of mycoflora unchanged, species of aspergilli, fusaria, penicillia and Trichoderma were predominant. HPLC, IR analysis revealed the presence of sarcosine derivative as an intermediary of glyphosate degradation in soil.


Subject(s)
Biodegradation, Environmental , Colony Count, Microbial , Fungi/drug effects , Glycine/analogs & derivatives , Herbicides/metabolism , Hydrogen-Ion Concentration , Sarcosine/metabolism , Soil Microbiology , Soil Pollutants/metabolism
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