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Rev. argent. microbiol ; 51(2): 110-118, jun. 2019. ilus, tab
Article in English | LILACS | ID: biblio-1013359


Although Cr(VI)-reducing and/or tolerant microorganisms have been investigated, there is no detailed information on the composition of the microbial community of the biocathode microbial fuel cell for Cr(VI) reduction. In this investigation, the bacterial diversity of a biocathode was analyzed using 454 pyrosequencing of the 16S rRNA gene. It was found that most bacteria belonged to phylum Proteobacteria (78.8%), Firmicutes (7.9%), Actinobacteria (6.6%) and Bacteroidetes (5.5%), commonly present in environments contaminated with Cr(VI). The dominance of the genus Pseudomonas (34.87%), followed by the genera Stenotrophomonas (5.8%), Shinella (4%), Papillibacter (3.96%), Brevundimonas (3.91%), Pseu-dochrobactrum (3.54%), Ochrobactrum (3.49%), Hydrogenophaga (2.88%), Rhodococcus (2.88%), Fluviicola (2.35%), and Alcaligenes (2.3%), was found. It is emphasized that some genera have not previously been associated with Cr(VI) reduction. This biocathode from waters contaminated with tannery effluents was able to remove Cr(VI) (97.83%) in the cathodic chamber. Additionally, through use of anaerobic sludge in the anodic chamber, the removal of 76.6% of organic matter (glucose) from synthetic waste water was achieved. In this study, an efficient biocathode for the reduction of Cr(VI) with future use in bioremediation, was characterized.

Aunque se ha investigado sobre los microorganismos reductores y/o tolerantes de Cr(VI), no hay información detallada sobre la composición de la comunidad microbiana del cátodo de una Celda de Combustible Microbiana para la reducción de Cr(VI). En esta investigación se analizó la diversidad bacteriana de un biocátodo usando pirosecuenciación 454 del gen 16S rRNA. Se encontró que la mayoría de las bacterias pertenecieron a los filos Proteobac-teria (78,8%), Firmicutes (7,9%), Actinobacteria (6,6%) y Bacteroidetes (5,5%), comúnmente presentes en ambientes contaminados con Cr(VI). Se encontró como género dominante a Pseudomonas (34,87%), seguido por los géneros Stenotrophomonas (5,8%), Shinella (4%), Papil-libacter (3,96%), Brevundimonas (3,91%), Pseudochrobactrum (3,54%), Ochrobactrum (3,49%), Hydrogenophaga (2,88%), Rhodococcus (2,88%), Fluviicola (2,35%) y Alcaligenes (2,3%). Se destaca que algunos géneros no han sido previamente asociados con la reducción de Cr(VI). Este biocátodo procedente de aguas contaminadas con efluentes de curtiembres fue capaz de remover Cr(VI) (97,83%) en la cámara catódica. Adicionalmente, a través del uso de lodo anaeróbico en la cámara anódica, se logró la remoción del 76,6% de materia orgánica (glucosa) a partir de agua residual sintética. En este estudio se caracterizó un eficiente biocátodo para la reducción de Cr(VI) con futuro uso en biorremediación.

RNA, Ribosomal, 16S/analysis , Actinobacteria/isolation & purification , Waste Water/microbiology , Bacteria/growth & development , Biodegradation, Environmental , Environmental Monitoring , Reducing Agents/analysis
Braz. j. microbiol ; 49(1): 38-44, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-889215


ABSTRACT Discharge of coke-oven wastewater to the environment may cause severe contamination to it and also threaten the flora and fauna, including human beings. Hence before dumping it is necessary to treat this dangerous effluent in order to minimize the damage to the environment. Conventional technologies have inherent drawbacks however, biological treatment is an advantageous alternative method. In the present study, bacteria were isolated from the soil collected from the sites contaminated by coke-oven effluent rich in phenol and cyanide. Nucleotides sequence alignment and phylogenetic analysis showed the identity of the selected phenol and cyanide degrading isolates NAUN-16 and NAUN-1B as Pseudomonas putida and Pseudomonas stutzeri, respectively. These two isolates tolerated phenol up to 1800 mg L-1 and cyanide up to 340 mg L-1 concentrations. The isolates were immobilized on activated charcoal, saw dust and fly ash. The effluent was passed through the column packed with immobilized cells with a flow rate of 5 mL min-1. The isolates showed degradation of phenol up to 80.5% and cyanide up to 80.6% and also had the ability to reduce biological oxygen demand, chemical oxygen demand and lower the pH of effluent from alkaline to near neutral. The study suggests the utilization of such potential bacterial strains in treating industrial effluent containing phenol and cyanide, before being thrown in any ecosystem.

Cyanides/metabolism , Phenol/metabolism , Pseudomonas putida/metabolism , Pseudomonas stutzeri/metabolism , Waste Disposal, Fluid/methods , Waste Water/microbiology , Biodegradation, Environmental , Cells, Immobilized/classification , Cells, Immobilized/metabolism , Coke/analysis , Cyanides/analysis , Industrial Waste/analysis , Phenol/analysis , Phylogeny , Pseudomonas putida/classification , Pseudomonas putida/genetics , Pseudomonas putida/isolation & purification , Pseudomonas stutzeri/classification , Pseudomonas stutzeri/genetics , Pseudomonas stutzeri/isolation & purification , Waste Water/analysis
Electron. j. biotechnol ; 29: 78-85, sept. 2017. tab, graf, ilus
Article in English | LILACS | ID: biblio-1017382


Background: Biohydrogen effluent contains a high concentration of volatile fatty acid (VFA) mainly as butyric, acetic, lactic and propionic acids. The presence of various VFAs (mixture VFAs) and their cooperative effects on two-stage biohythane production need to be further studied. The effect of VFA concentrations in biohydrogen effluent of palm oil mill effluent (POME) on methane yield in methane stage of biohythane production was investigated. Results: The methane yield obtained in low VFA loading (0.9 and 1.8 g/L) was 15­20% times greater than that of high VFA loading (3.6 and 4.7 g/L). Butyric acid at high concentrations (8 g/L) has the individual significantly negative effect the methane production process (P b 0.05). Lactic, acetic and butyric acid mixed with propionic acid at a concentration higher than 0.5 g/L has an interaction significantly negative effect on the methanogenesis process (P b 0.05). Inhibition condition had a negative effect on both bacteria and archaea with inhibited on Geobacillus sp., Thermoanaerobacterium thermosaccharolyticum, Methanoculleus thermophilus and Methanothermobacter delfuvii resulting in low methane yield. Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production.

Propionates/metabolism , Butyrates/metabolism , Waste Water/microbiology , Methane/biosynthesis , Propionates/analysis , Butyrates/analysis , Palm Oil , Methanobacteriaceae , Archaea , Methanomicrobiaceae , Geobacillus , Fermentation , Waste Water/analysis , Hydrogen , Anaerobiosis
Braz. j. microbiol ; 47(3): 571-586, July-Sept. 2016. tab, graf
Article in English | LILACS | ID: lil-788980


ABSTRACT An analysis of wastewater samples collected from different industrial regions of Egypt demonstrated dangerously high levels of nickel (0.27-31.50 mg L-1), chromium (1.50-7.41 mg L-1) and zinc (1.91-9.74 mg L-1) in the effluents. Alarmingly, these heavy metals are among the most toxic knownones to humans and wildlife. Sixty-nine Actinomycete isolates derived from contaminated sites were evaluated under single, binary, and ternary systems for their biosorption capacity for Ni2+, Cr6+ and Zn2+ from aqueous solutions. The results of the study identified isolates MORSY1948 and MORSY2014 as the most active biosorbents. Phenotypic and chemotypic characterization along with molecular phylogenetic evidence confirmed that the two strains are members of the Nocardiopsis and Nocardia genera, respectively. The results also proved that for both the strains, heavy metal reduction was more efficient with dead rather than live biomass. The affinity of the dead biomass of MORSY1948 strain for Ni2+, Cr6+ and Zn2+ under the optimized pH conditions of 7, 8 and 7, respectively at 40 °C temperature with 0.3% biosorbent dosage was found to be as follows: Ni2+ (87.90%) > Zn2+ (84.15%) > Cr6+ (63.75%). However, the dead biomass of MORSY2014 strain under conditions of pH 8 and 50 °C temperature with 0.3% biosorbent dose exhibited the highest affinity which was as follows: Cr6+ (95.22%) > Ni2+ (93.53%) > Zn2+ (90.37%). All heavy metals under study were found to be removed from aqueous solutions in entirety when the sorbent dosage was increased to 0.4%.

Metals, Heavy/metabolism , Nocardia/classification , Nocardia/metabolism , Temperature , Time Factors , Water Pollutants, Chemical/metabolism , Biodegradation, Environmental , RNA, Ribosomal, 16S/genetics , Biomass , Metals, Heavy/toxicity , Adsorption , Egypt , Waste Water/microbiology , Hydrogen-Ion Concentration , Industrial Waste , Nocardia/isolation & purification , Nocardia/genetics
Rev. argent. microbiol ; 48(3): 245-251, set. 2016. graf, tab
Article in English | LILACS | ID: biblio-843169


The biotechnology sector is continually seeking sustainable and more economical bioprocesses. Fermentation media produced with cheap components or wastes reduce production costs. Moreover, if wastes are used, they contribute to avoid environmental pollution. In this work, microbial growth media based on molasses or acidified glycerol as carbon sources and fertilizer as nitrogen source were tested for the production of a whole-cell catalyst that could be used in Cr(VI)-containing wastewater treatments. Results showed that the highest biomass production yield was obtained with a medium containing acidified glycerol 5% v/v and fertilizer 0.6% v/v. The biomass produced using this medium was immobilized in calcium alginate beads and used as catalyst in the biotransformation of Cr(VI) into Cr(III). The catalyst could be efficiently used for 5 reduction cycles of 40 mg/l Cr(VI) each. Cr(III) retention assays were performed to determine whether Cr(III) could be retained by the catalyst avoiding its solubilization in the supernatants. The retention capacity of the catalyst at 32 °C and pH 3.0 was 3 mg Cr(III)/g. Both an alternative and economical fermentation medium is here proposed for the optimization of Cr(VI)-containing wastewater treatment.

El sector industrial biotecnológico continuamente busca bioprocesos más económicos y sustentables. El uso de medios de cultivo producidos con componentes de bajo costo o con residuos reduce el presupuesto global del proceso y, particularmente si se utilizan residuos, se contribuye, además, a evitar la contaminación ambiental. En este trabajo se probaron medios de cultivo basados en melaza de caña o glicerol ácido como fuentes de carbono y energía, y fertilizante como fuente de nitrógeno, para la producción de un biocatalizador que podría ser usado para el tratamiento de aguas residuales que contienen Cr(VI). Los resultados mostraron que el mayor rendimiento de producción de biomasa se obtuvo con un medio que contenía 5% v/v de glicerol ácido y 0,6% v/v de fertilizante. Utilizando este medio se produjo la biomasa suficiente para la biotransformación de Cr(VI) a Cr(III), luego de ser inmovilizada en alginato de calcio. El proceso pudo ser aplicado eficientemente durante 5 ciclos de reducción de 40 mg/l de Cr(VI) cada uno. Además, se realizaron ensayos de retención de Cr(III) para determinar si esta especie química podría ser removida de la solución por interacción con el biocatalizador. La capacidad de retención obtenida por el biocatalizador a 32 °C y pH 3 fue de 3 mg de Cr(III)/g. De esta manera, se propone un medio de cultivo alternativo y económico para la efectivización de un tratamiento de aguas residuales que contengan Cr(VI).

Biotransformation , Water Purification/methods , Low Cost Technology/economics , Biocatalysis , Waste Water/microbiology , Chromium/analysis , Water Purification/economics
Braz. j. microbiol ; 47(1): 73-84, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775103


Abstract Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens), and msbl6 (candidate division) were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%, 8.9%, and 8.8% of the total bacteria identified, respectively. The dominant bacteria isolated were Clostridium, Bacteroides, Desulfobulbus, Desulfomicrobium, Desulfovibrio and Desulfotomaculum. Our results revealed the presence of new species, genera and families of microorganisms. The most interesting strains were characterised. Three new bacteria involved in anaerobic digestion of abattoir wastewater were published.

Abattoirs , Biota , Bacteria/classification , Bacteria/genetics , Waste Water/microbiology , Anaerobiosis
Braz. j. microbiol ; 47(1): 18-24, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775112


Abstract Phenol and phenolic compounds are environmental pollutants present in industrial wastewaters such as coal tar, oil refineries and petrochemical plants. Phenol removal from industrial effluents is extremely important for the protection of environment. Usually, phenol degradation is carried out by physicochemical methods that are costly and produce hazardous metabolites. Recently, phenol biodegradation has been considered. Yeasts are the most important phenol biodegraders. In this study, the phenol-degrading yeast from environmental samples (soil and wastewater) was isolated from the coking plant of Zarand, Kerman. Then total heterotrophic yeasts were counted. The soil samples had higher rates of yeast degrader, in comparison to wastewater samples. After three passages, four yeasts (K1, K2, K7 and K11) that had the highest growth rate were selected for further study. Also, these yeasts were able to remove phenol measured by Gibbs reagent. The effect of four different concentrations of phenol (50, 125, 200 and 275) mg L−1 was measured and three degradation patterns in these yeasts were observed. The hydrophobicity and emulsification activity were measured in all eleven yeasts. Finally, strong yeasts in phenol degrading yeasts were identified by molecular method using amplification of 18S rRNA gene region. The sequencing results showed that these isolated yeasts belonged to Candida tropicalis strain K1, Pichia guilliermondii strain K2, Meyerozyma guilliermondii strain K7 and C. tropicalis strain K11.

Industrial Waste , Phenol/metabolism , Waste Water/microbiology , Water Pollutants, Chemical/metabolism , Yeasts/classification , Yeasts/metabolism , Biotransformation , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Iran , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Soil Microbiology , Yeasts/genetics , Yeasts/isolation & purification
Braz. j. microbiol ; 46(2): 415-424, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749732


Dyes are the most difficult constituents to remove by conventional biological wastewater treatment. Colored wastewater is mainly eliminated by physical and chemical procedures, which are very expensive and have drawbacks. Therefore, the advantage of using biological processes, such as the biotransformation of dyes, is that they may lead to complete mineralization or formation of less toxic products. To prove the possibility of using fungal processes for decolorization and other applications, the analysis of the toxicity of the processes' products is required. The decolorization of the mixture of two dyes from different classes - triphenylmethane brilliant green and azo Evans blue (GB - total concentration 0.08 g/L, proportion 1:1 w/w) - by Pleurotus ostreatus (BWPH and MB), Gloeophyllum odoratum (DCa), RWP17 (Polyporus picipes) and Fusarium oxysporum (G1) was studied. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated at the end of the experiment. The mixture of dyes was significantly removed by all the strains that were tested with 96 h of experimental time. However, differences among strains from the same species (P. ostreatus) were noted. Shaking improved the efficacy and rate of the dye removal. In static samples, the removal of the mixture reached more than 51.9% and in shaken samples, more than 79.2%. Tests using the dead biomass of the fungi only adsorbed up to 37% of the dye mixture (strain BWPH), which suggests that the process with the living biomass involves the biotransformation of the dyes. The best results were reached for the MB strain, which removed 90% of the tested mixture under shaking conditions. Regardless of the efficacy of the dye removal, toxicity decreased from class V to class III in tests with D. magna. Tests with L. minor control samples were classified as class IV, and samples with certain strains were non-toxic. The highest phytotoxicity decrease was noted in shaken samples where the elimination of dye mixture was the best.

Animals , Basidiomycota/growth & development , Basidiomycota/metabolism , Evans Blue/metabolism , Fusarium/growth & development , Fusarium/metabolism , Rosaniline Dyes/metabolism , Waste Water/microbiology , Araceae/drug effects , Araceae/physiology , Biotransformation , Cell Survival/drug effects , Daphnia/drug effects , Daphnia/physiology , Evans Blue/toxicity , Rosaniline Dyes/toxicity , Water Purification/methods
Braz. j. microbiol ; 46(2): 407-413, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749745


The objective of this study was to evaluate the exopolysaccharide (EPS) production by Rhizobium leguminosarum cultivated in wastewater generated by oil companies (WWOC1 and WWOC2) and fish processing industry (WWFP). The results obtained in Erlenmeyer flasks indicated that the rhizobial strain grew well in industrial wastewater. Generally, wastewater composition affected the growth and the EPS production. WWFP allowed good bacterial growth similar to that obtained with the standard medium (YMB). During growth, various quantities of EPS were produced and yields varied depending on the media. Growing in YMB, EPS production did not exceed 9.7 g/L obtained after 72 h of growth. In wastewater, the maximum EPS value reached 11.1 g/L obtained with the fish processing wastewater, after 72 h of growth. The use of a mixture of the oil company wastewater (WWOC2) and the fish processing wastewater (WWFP) as culture medium affected not only the rhizobial strain growth, but also EPS production. The highest EPS (42.4 g/L, after 96 h of culture) was obtained using a ratio of WWFP and WWOC2 of 50:50 (v:v). Therefore, this work shows the ability of Rhizobium leguminosarum, growing in industrial wastewater as new economic medium, to produce EPS. This biopolymer could be applied in enormous biotechnological areas.

Polysaccharides, Bacterial/metabolism , Rhizobium leguminosarum/growth & development , Rhizobium leguminosarum/metabolism , Waste Water/microbiology , Food Industry , Industrial Waste , Oil and Gas Industry
Braz. j. microbiol ; 45(4): 1309-1315, Oct.-Dec. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-741281


The present study proposed the isolation of arsenic resistant bacteria from wastewater. Only three bacterial isolates (MNZ1, MNZ4 and MNZ6) were able to grow in high concentrations of arsenic. The minimum inhibitory concentrations of arsenic against MNZ1, MNZ4 and MNZ6 were 300 mg/L, 300 mg/L and 370 mg/L respectively. The isolated strains showed maximum growth at 37 ºC and at 7.0 pH in control but in arsenite stress Luria Bertani broth the bacterial growth is lower than control. All strains were arsenite oxidizing. All strains were biochemically characterized and ribotyping (16S rRNA) was done for the purpose of identification which confirmed that MNZ1 was homologous to Enterobacter sp. while MNZ4 and MNZ6 showed their maximum homology with Klebsiella pneumoniae. The protein profiling of these strains showed in arsenic stressed and non stressed conditions, so no bands of induced proteins appeared in stressed conditions. The bacterial isolates can be exploited for bioremediation of arsenic containing wastes, since they seem to have the potential to oxidize the arsenite (more toxic) into arsenate (less toxic) form.

Anti-Bacterial Agents/metabolism , Arsenic/metabolism , Drug Resistance, Bacterial , Enterobacter/drug effects , Klebsiella pneumoniae/drug effects , Waste Water/microbiology , Arsenites/metabolism , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Enterobacter/classification , Enterobacter/growth & development , Enterobacter/isolation & purification , Hydrogen-Ion Concentration , Klebsiella pneumoniae/classification , Klebsiella pneumoniae/growth & development , Klebsiella pneumoniae/isolation & purification , Microbial Sensitivity Tests , Oxidation-Reduction , Proteome/analysis , Ribotyping , /genetics , Temperature
Article in English | IMSEAR | ID: sea-163215


Aims: This study was conducted to determine the effect of different doses of gamma radiation on Multi-drug resistant Pseudomonas aeruginosa isolated from River Nile at Rosetta branch and associated drains in Egypt. Place and Duration of Study: The study was started with samples collection in August 2010 through April 2011 in the Microbiology Dep., Central Laboratory for Environmental Quality Monitoring (CLEQM), National Water Research Center (NWRC), Cairo, Egypt and the National Centre for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt. Methodology: Water samples were processed using membrane filtration, 144 strains of P. aeruginosa were isolated and identified and their antibiotic susceptibility was determined against 20 different antibiotics using agar disc diffusion method. Irradiation of bacterial isolates was processed using gamma irradiation unit of cobalt (Co60) and the D10-value was calculated from the survival curve. Results: Isolates were categorized as multi-drug resistant Pseudomonas aeruginosa (MDRPA). 125 (86.8%) were found to be extensively drug resistant (XDR) and 19 (13.2 %) were characterized as possible pan drug resistant (PDR). The highest resistance (100%) was mostly directed to amoxycillin/clavulanic acid, ampicillin, carbenicillin, methicillin, cephalothin, kanamycin, vancomycin, tetracycline, erythromycin, clindamycin, trimethoprim/sulfamethoxazole, nitrofurantoin and chloramphenicol. More than 75% of isolates were sensitive to norfloxacin (82.6%), piperacillin (81.2%), amikacin (79.2%) and tobramycin (77.8%). 63.2%, 26.4% and 14.6% of isolates were sensitive to ofloxacin, cefotaxime and ceftriaxone, respectively. The viable counts of MDRPA decreased with increasing radiation doses of gamma rays up to the lethal dose (3 kGy). The counts of 0.5, 1.0, 1.5, 2.0, 2.5 kGy irradiated samples were respectively 7.8, 6.5, 4.7, 2.3& 1 log10 and the D10-value calculated from the survival curve was 0.27 kGy. Conclusion: Contaminated fresh water may act as reservoirs for antibiotic resistant pathogens. Regular monitoring of Multi-drug resistant pathogens in aquatic environments should be adopted constantly. Gamma radiation demonstrates a potential value for wastewater treatment and pollution control.

Africa South of the Sahara , Drug Resistance, Multiple, Bacterial/epidemiology , Drug Resistance, Multiple, Bacterial/radiation effects , Egypt , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/isolation & purification , Pseudomonas aeruginosa/radiation effects , Radiation, Ionizing , Rivers/microbiology , Waste Water/microbiology , Waste Water/therapy
Article in English | IMSEAR | ID: sea-163098


Microbial lipases have been heightened in bioremediation and various industries. Place and Duration of Study: Department of Microbiology, Ekiti State University, Ado-Ekiti, Ekiti State, Nigeria, between September 2010 and August 2011. To identify the lipolytic enzyme producing microbial strains in domestic oil rich wastewater, the 16S rRNA gene was amplified and sequenced. The sequences were used to identify the strains by comparing with related sequences in database using BLAST analysis. The enzyme activity was quantified by HPLC analysis. All the lipolytic bacteria showed appreciable growth rates in the wastewater (between 0.67 and 1.67 mg/day) within 5 days. The most effective lipolytic bacteria isolates in the oil-rich wastewater were two species of the genus Pseudomonas and one of Bacillus. Comparing the weights on the first day to the twelfth day values when lipolytic organisms were grown in palm oil, some appreciable increases in weight difference were recorded in some isolates: 28.3%, 7.84%, 4.44% and 6.98% for Pseudomonas, Staphylococcus, Bacillus and Klebsiella, respectively. The weight increase of each of the microbial cells in palm oil culture was usually lesser than what was obtained in the oil-rich wastewater culture. Two isolates showed high similar sequence (99%) to that of Pseudomonas aeruginosa and Lysinibacillus sphaericus, respectively. From palm oil, Lysinibacillus sp. produced various forms of fatty acids in the medium, including myristic acid (2.61%), palmitic acid (6.22%), stearic acid (5.18%) and arachidic (3.66%). These strains are versatile in utilizing the limited nutrient and had the ability to grow appreciably in the toxic condition (soap solution), suggesting that they may serve as candidates in treating dietary oil-rich wastewater.

Bacillaceae/isolation & purification , Bacillaceae/physiology , Fatty Acids/metabolism , Lipid Mobilization/etiology , Lipid Mobilization/physiology , Polymerase Chain Reaction , Pseudomonas aeruginosa/isolation & purification , Pseudomonas aeruginosa/physiology , Waste Water/microbiology , Water Pollutants
Article in English | IMSEAR | ID: sea-162932


Aims: Untreated wastewater is usually used for crop irrigation in developing countries; however it contains a lot of pathogenic bacteria. This study was carried out to determine the fate of E. coli contained in wastewater in a hydromorphic soil. Study Design: Environmental microbiology Place and Duration of the Study: This study was carried out in the experimental field of the Dschang University, during the dry season (November 2011- Mars 2012) and the rainy season (June 2012-September 2012). Methodology: Six plots of 4 m2 each were tilled in 400 m2 surface area in the dry and in the rainy seasons. Wastewater was collected from the experimental wastewater treatment station in the University of Dschang; it was applied on three plots, and three other plots were used as controls. Once every week, soil samples were taken on the surface (0 - 10 cm), in the medium (20 - 30 cm) and at the water table level (40 - 50 cm). Levels of E. coli in soil samples were determined on “Lactose Tergitol® 7 Agar with TTC” medium, and midbiochemical confirmation tests were carried out (tests of indol, Simmons citrate, gas production, mobility, fermentation of mannitol, glucose and lactose). Results: In the rainy season, E. coli was detected on the soil surface until the 112th day, while in the dry season detection did not exceed the 63rd day. E. coli was detected in the deeper layers of the soil (20 - 30 and 40 - 50 cm) from the 14th and the 70th day respectively. This helps to estimate the speed of vertical migration to be between 5 and 18 mm per day. Conclusion: E. coli bacteria contained in urban wastewater survive for a long-time in hydromorphic soils and reach significant depths, and can consequently pose serious problems of public health.

Environmental Microbiology/analysis , Environmental Microbiology/methods , Escherichia coli/growth & development , Rain , Soil/chemistry , Soil/microbiology , Soil Microbiology/analysis , Tropical Climate , Waste Water/microbiology
Rev. salud pública ; 15(5): 780-793, set.-oct. 2013. ilus, tab
Article in Spanish | LILACS | ID: lil-709098


RESUMEN Objetivo Realizar la caracterización físico-química, microbiológica y parasitológica en biosólidos generados en la planta de tratamiento de agua residual San Fernando, Itagüí (Antioquia, Colombia). Métodos Se analizaron 12 muestras de biosólido tomadas cada mes, de enero a diciembre de 2010 a las cuales se les realizó un análisis físico-químico y microbiológico de acuerdo a lo establecido en la Norma Técnica Colombiana 5167. Para la determinación y viabilidad de huevos de helmintos se siguió el protocolo descrito en la Norma Oficial Mexicana 004 con modificaciones. Resultados En las doce muestras analizadas, se encontró una concentración de huevos de Ascarislumbricoides en un rango entre 4 a 22 huevos viables/2g ST. Salmonella estuvo presente en todas las muestras y las Enterobacterias estuvieron en una concentración mínima de 3000 UFC/g. La concentración de los metales pesados estuvo dentro de los valores recomendados por la norma. Los macro y micronutrientes cumplieron con los parámetros establecidos para los materiales orgánicos usados como abonos. No hubo asociación entre la precipitación y el contenido de patógenos en los biosólidos. Conclusión Los biosólidos generados en la planta San Fernando tienen un gran potencial para ser usados como abono orgánico, no obstante, deben ser sometidos a procesos de sanitización con el propósito de cumplir con los parámetros indicados en la Norma NTC 5167.

ABSTRACT Objective This study was aimed at evaluating pertinent physicochemical and microbiological (bacteria and parasites) parameters regarding the biosolids produced by the San Fernando wastewater treatment plant (WWTP) in Itagui, Antioquia, Colombia. Methods Twelve samples were collected and evaluated every month from January to December during 2010. The chemical, physical and microbiological tests followed the protocol described in Colombian technical guideline 5167. The protocol described in Mexican official Norm 004 (with some modifications) was used for identifying helminth ova and assessing their viability. Results All samples proved positive for Ascarislumbricoides, viable ova count ranging from 4 to 22 eggs/2gTS. Both Salmonella and Enterobacteriawere detected in all samples evaluated, the latter having 3,000 colony forming unit (CFU)/g minimum concentration. Biosolid sample values met the heavy metal concentration requirement established by national guidelines. There was no statistical association between rainfall and the pathogen's presence in the biosolids. Conclusion Our results suggested that the biosolids being produced by the San Fernando wastewater treatment plant (WWTP) could be used as organic fertilizer; however they should be treated/sanitized to meet the stipulations in Colombian technical guideline 5167.

Solid Waste , Waste Water , Colombia , Waste Water/analysis , Waste Water/microbiology , Waste Water/parasitology
Braz. j. microbiol ; 44(3): 799-806, July-Sept. 2013. ilus, tab
Article in English | LILACS | ID: lil-699813


This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL) in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%), penicillin (63.8%), co-trimoxazole (55.1%), norfloxacin (53.6%), methicillin (52.7%), cefuroxime (39.1%), cefotaxime (23.2%) and cefixime (20.3%). Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC) showed a high level of resistance (800-1600 µg/mL) to one or more antibiotics. Sixty three (91%) isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates), ampicillin (62.3%), cefodroxil (52.2%), cefotoxime (21.7%) and cefuroxime (18.8%). Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 x 10-3 to 8.8 x 10-4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention.

Humans , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Enterobacteriaceae/genetics , Enterobacteriaceae/isolation & purification , Gene Transfer, Horizontal , Waste Water/microbiology , Conjugation, Genetic , Enterobacteriaceae/drug effects , /genetics , Hospitals , Incidence , Microbial Sensitivity Tests , R Factors , beta-Lactamases/metabolism
Rev. argent. microbiol ; 45(1): 57-60, mar. 2013.
Article in Spanish | LILACS, BINACIS | ID: biblio-1171766


The present work sought to detect the presence of Pseudomonas spp. at different stages of an effluent treatment plant using the Australian system of stabilization ponds, and to determine the susceptibility of those isolates to different antimicrobials. Thirty-four isolates of Pseudomonas spp. derived from effluent treatment station water samples were collected near the transfer ducts between the ponds in November/2008 and december/2009. Among the Pseudomonas spp. isolates, 47.05

showed susceptibility to all antimicrobials tested, 20.58

were resistant to cefepime, and 24

showed intermediate resistance to streptomycin. No Pseudomonas spp. isolates were found in the final pond, or in post-treatment effluents. The Pseudomonas spp. isolates did not exhibit multiresistance to the antimicrobials tested.

Abattoirs , Pseudomonas/drug effects , Drug Resistance, Microbial , Sus scrofa/microbiology , Animals , Anti-Bacterial Agents/pharmacology , Brazil , Waste Disposal, Fluid/methods , Medical Waste Disposal/methods , Species Specificity , Retrospective Studies , Water Microbiology , Pseudomonas/classification , Pseudomonas/isolation & purification , Industrial Waste , Swine , Disk Diffusion Antimicrobial Tests , Waste Water/microbiology
Braz. j. microbiol ; 43(1): 356-362, Jan.-Mar. 2012. ilus, tab
Article in English | LILACS | ID: lil-622824


Pseudomonas fluorescens phages from sewage were tested against P. fluorescens isolates of soil and sewage. The phages were characterized as to host range, morphology, structural proteins and genome fingerprint. Of the seven phages isolated, one was found to be abundant in sewage (5.9×10(7) pfu/mL), having broad host range, and distinct protein and DNA profile when compared to the other six phages. DNA restriction and protein profiles of the phages and their morphology indicate the diversity in the sewage environment. None of the isolates from the rhizosphere regions of various cultivated soils were susceptible to phages isolated from sewage.

Waste Water/analysis , Waste Water/microbiology , Genome, Bacterial , Pseudomonas Phages , Proteins/analysis , Pseudomonas fluorescens/genetics , Pseudomonas fluorescens/isolation & purification , Electrophoresis, Agar Gel , Enzyme Activation , Pseudomonas , Water Samples
Rev. cuba. salud pública ; 37(1): 61-73, ene.-mar. 2011.
Article in Spanish | LILACS | ID: lil-581610


El agua dulce es un recurso vital pero cada día está más escaso debido al crecimiento demográfico, la urbanización y la industrialización, a lo que se suman los conflictos asociados a los cambios climáticos. El propósito de este estudio es aportar información actualizada sobre las guías de la OMS para el uso seguro de las aguas residuales en la agricultura. Se identificaron 33 documentos relacionados con el tema, de ellos se seleccionaron 13 publicados entre 1994 y 2007, que contemplan informes de la UNESCO, guías y manual de la OMS y revisiones críticas del tema. Se resume información sobre las guías de la OMS y la importancia de su incorporación paulatina en Cuba, se destacan, dentro de los Objetivos del Desarrollo del Milenio, aquellos relacionados con el uso seguro de aguas residuales y excretas para la agricultura y acuicultura, que justifican la actual importancia de las nuevas guías propuestas. El uso de aguas residuales en la agricultura puede aportar beneficios, pero su uso no controlado generalmente está relacionado con impactos negativos sobre la salud humana. En Cuba, el reuso del agua es poco utilizado pues si bien la agricultura urbana se ha desarrollado últimamente, se realiza con agua potable. Se debe considerar en el país las guías de la OMS para la futura valoración del uso de las aguas residuales tratadas en la agricultura sin riesgo para la salud y obtener resultados beneficiosos para la población y el ambiente. En resumen, se enumeran aspectos a considerar para el uso seguro de las aguas residuales en la agricultura en Cuba, necesarios para implementar programas nacionales de vigilancia sanitaria y de agricultura con énfasis en los aspectos microbiológicos

Drinking water is a vital but increasingly dwindling resource due to the population growth, housing planning, industrialization associated to new potential demands upon the existing water resources, to which climatic change-related events are added. The objective of this study was to provide updated information on the WHO guidelines for the safe use of wastewater in agriculture. A total of 33 documents about this topic were identified; 13 of them published from 1994 to 2007 were selected since they included UNESCO reports, WHO guidelines and manual and critical reviews. Information was summarized on the WHO guidelines and the importance of their gradual application in Cuba. Among the Millennium Development Goals, those related to the safe use of wastewater and excreta for agriculture and aquaculture were underscored because they supported the present importance of the new suggested guidelines. The use of wastewaters in agriculture may bring about benefits, but their use without restriction is generally related to negative impact on the human health. The water reuse is not very common in Cuba; although the agriculture in urban areas has developed in the last few years, it depends on drinking water. The WHO guidelines must be taken into consideration for the future assessment of the use of treated wastewater in agriculture without causing any risk for health, and for the benefits it may bring to the environment and the population as well. In summary, some aspects to be considered to safely use wastewater in the Cuban agriculture, which are also necessary to implement national health and agricultural surveillance programs centered on microbiological aspects, were listed

Waste Water/microbiology , Organic Agriculture
Rio de Janeiro; s.n; 2011. 91 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: lil-613887


Para avaliar um sistema integrado de agrucultura foram realizadas análises microbiológicas da água utilizada neste sistema e determinada a incidência e resistência antimicrobiana dos enteropatógenos no ecossistema relacionado. As amostras de água testadas apresentaram 32,9% de taxas de coliformes fecais (<- 1.600/100mL), de acordo com a OMS para piscicultura em águas residuais. Salmonella spp. foram detectadas em 14,5% das amostras. De um total de 33 cepas, 15,1% eram resistentes a um ou dois antimicrobianos testados e resistência a múltiplas drogas não foi observada. Aeromonas spp. foram identificadas em 91,6% das amostras. De um total de 416 cepas, resistência a uma classe de antimicrobianos foi observada em 66,3% e a multirresistência às drogas em 37,7%. Na avaliação da virulência dos isolados de Aeromonas hydrophila, 85,3% das cepas apresentaram Beta-hemólise nos três diferentes tipos de eritrócitos empregados e 99,1% nos eritrócitos de coelho e cavalo, sendo possível a caracterização através da PCR do gene aerA e lip, em 100% das amostras. Os resultados obtidos apontam para a relevância quanto às vantagens da implementação de um sistema integrado, disponibilizando alimentos com custo reduzido, porém este sistema necessita de um controle rígido e efetivo para que estes produtos não constituam veículos para a disseminação de doenças.

To evaluate an integrated aquaculture system, microbiological analyses of water used in this system were carried out and the incidence and antimicrobial resistance of enteropathogens were determined in the related ecosystem. Water samples tested had 32.9% of fecal coliforms rates (<-1600/100mL) in accordance with WHO for psiculture in wastewater. Salmonella spp. were detected in 14.5% of the samples. From a total of 33 strains, 15.1% were resistant to one or two antimicrobial drugs tested and multidrug-resistance was not observed. Aeromonas spp. were identified in 91.6% of the samples. From a total of 416 strains, resistance to one antimicrobial class was observed in 66.3% and multidrug-resistance in 37.7%. In relation to virulence factors of Aeromonas hydrophila, 85.3% of the strains showed beta-hemolysis in three different types of erythrocytes and 99.1% in horse and rabbit erythrocytes. It was possible to characterize by PCR assay, the genes aerA and lip in 100% of the strains. The results indicate the relevance of the benefits of implementing an integrated system, providing food with reduced cost, but this system requires a strict and effective control so that these products do not constitute a vehicle for the spread of disease.

Aeromonas , Aeromonas/isolation & purification , Waste Water/analysis , Waste Water/microbiology , Salmonella , Salmonella/isolation & purification , Shigella , Shigella/isolation & purification , Water Microbiology , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Ecosystem , Culture Media/analysis , Virulence Factors , Vibrio , Vibrio/isolation & purification
Acta cir. bras ; 20(supl.1): 253-256, 2005.
Article in Portuguese | LILACS | ID: lil-474158


OBJECTIVE: Test the resistance to antibiotics and heavy metals of E. coli strains isolated from storm sewer water and adjacent seawater samples from three beaches (Meio, Area Preta and Ponta Negra) in the city of Natal/RN/Brazil, and determine the association among those characteristics. METHODS: A total of 98 strains of E. coli, 50 from storm sewers and 48 from the seawater were analyzed resistance to several antimicrobials by disk diffusion and agar dilution and to heavy metals by dilution in plates with aqueous solutions of CuSO4 incorporated to Mueller Hinton agar in concentrations of 100, 150, 200 and 250 ig/mL and HgCl2 in concentrations of 5, 10, 20, 30, and 50 ig/mL. Standard strains were used as control. RESULTS: Among the twelve antimicrobials tested, 28 (28.5%) of E. coli strains showed resistance to different antimicrobials drugs to seven. The greatest resistance rate was to tetracycline (46.4%), ampicillin (39.3%) and cephalothin (32.1%), with the remainder (nitrophurantoine, nalidixic acid, sulfatomexazol-trimethoprin and chloramphenicol) at lower percentages. Among the heavy metals, all the strains (100%) were resistant to zinc and to copper in the largest concentration (250 ig/mL), and 18.4% were resistant to HgCl the 50 ig/mL. Ten (55.5%) of the E. coli strains resistant to Hg were associated to resistance to antibiotics. CONCLUSION: These results suggest the existence of extra chromosomal genes in E. coli strains isolated from storm sewer water and adjacent seawater, which encoders of the resistance to antibiotics and heavy metals.

Anti-Bacterial Agents/pharmacology , Fresh Water/microbiology , Seawater/microbiology , Escherichia coli/drug effects , Metals, Heavy/pharmacology , Fresh Water/chemistry , Seawater/chemistry , Waste Water/analysis , Waste Water/microbiology , Rain/chemistry , Rain/microbiology , Escherichia coli/isolation & purification , Microbial Sensitivity Tests , Drug Resistance, Multiple , Water Microbiology