Evaluación del consorcio entre Pleurotus ostreatus, Trametes versicolor y bacterias aeróbicas para remoción de colorantes sintéticos / Evaluation of the consortium between Pleurotus ostreatus, Trametes versicolor and aerobic bacteria for removal of synthetic dye

RESUMEN Los residuos líquidos producidos al elaborar tinciones biológicas contienen mezclas de compuestos químicos y microorganismos, que generan un elevado impacto ambiental si no son tratados adecuadamente. Por esta razón, en el presente trabajo se evaluaron a Pleurotus ostreatus, Trametes versicolor, Enterobacter xianfangensis, Pseudomonas azotoformans, Pseudomonas sp., Bacillus subtilis y Pseudomonas fluorescens, para el tratamiento de un residuo líquido que contenía colorantes trifenilmetánicos y azóicos, a escala de laboratorio. Inicialmente, se seleccionaron las cepas con menor efecto antagónico y se determinó su potencial para producir las enzimas Lacasa, Manganeso Peroxidasa y Lignino Peroxidasa, al emplear sustratos inductores y mezclas de colorantes. Para el consorcio fúngico/bacteriano la disminución de las unidades de color y demanda química de oxígeno fueron del 99 % y 70 % a las 96 h. La remoción de estos parámetros se relacionó con la interacción positiva e incremento de las poblaciones de hongos, bacterias y la producción de enzimas ligninolíticas, obteniendo valores a las 96 h de 7.0 y 14.0 unidades logarítmicas para hongos y bacterias, con unas actividades enzimáticas de 75 U/L, 205 U/L y 0.63 U/L para Lacasa, MnP y LiP, respectivamente. Con el presente trabajo se demostró que con el uso consorcios fúngicos/bacterianos se incrementa la remoción de colorantes y se disminuye el tiempo de proceso. Sugiriendo que estos microorganismos podrían ser evaluados en plantas de tratamiento que integren diferentes unidades de tratamiento para optimizar la remoción de contaminantes con baja biodegradabilidad.

ABSTRACT The liquid wastes generated when biological stains are prepared, contain a mixture of chemical compounds and microorganisms, with high environmental impact. For this reason, Pleurotus ostreatus, Trametes versicolor, Enterobacter xianfangensis, Pseudomonas azotoformans, Pseudomonas sp., Bacillus subtilis and Pseudomonas fluorescens, were used to evaluate the treatment of a liquid waste containing triphenylmethane and azo dyes, on a laboratory scale. Initially, the strains with less antagonistic effect among them were selected for their potential to produce enzymes as Laccase, Manganese Peroxidase and Lignin Peroxidase. The enzymatic activity was determined by using inducing substrates and dye mixtures. For fungal/bacterial consortium, the decrease in color, Chemical Oxygen Demand and in Biochemical Oxygen demand was of 99 %, 70 % and 65 % at 96 h, respectively. The removal of these parameters was related to the positive interaction between the populations of fungi, bacteria and the production of ligninolytic enzymes, obtaining values of 7.0 and 14.0 logarithmic units for fungi and total bacteria at 96 h with enzymatic activities of 75 U/ L, 205 U/L and 0.63 U/L for Laccase, MnP and LiP. The present work demonstrates that using of fungal/bacterial consortia, the removal of dyes is increased, and the process time is decreased. Suggesting that these microorganisms could be evaluated in treatment plants that integrate different treatment units to optimize the removal of contaminants with low biodegradability.

Utilization of bacterial consortium for oil sludge biodegradation using bioslurry method

Aims@#Oil sludge is one of pollutant sources in the environment. Bacterial abundance, interaction, and compatibility of environmental factors ensure the success of biodegradation. The purpose of this study was to determine the effectiveness of bacterial consortium in degrading oil sludge using bioslurry method. @*Methodology and results@#The research design used was completely randomized design 4×5 with variation of bacterial consortium concentration and incubation time. Composition of contaminant and liquid phase in bioslurry method was 1:9 ratio with aeration, at room temperature. The liquid phase comprises distilled water with the addition of 2% (v/v) of molasses as nutrient for bacterial growth. Bacterial growth was evaluated using the Total Plate Count (TPC) method. Total Petroleum Hydrocarbon (TPH) measurements were evaluated using the gravimetric method while the oil sludge hydrocarbon component was evaluated by Gas Chromatography Mass Spectrophotometry (GCMS). The pH and temperature data were analyzed descriptively while TPC and TPH data were analyzed using Two Way ANOVA (α=0.05). The bacterial consortium could grow on oil sludge hydrocarbon substrate with a range of temperature of 29 °C-32 °C and an optimum pH of 7. Biodegradation of TPH was 70.48% at consortium concentration of 15% in 14 days of incubation. @*Conclusion, significance and impact of study@#Biodegradation of oil sludge using a bacterial consortium by bioslurry method is one of the effective methods to reduce pollutants in the management of oil sludge.

Stenotrophomonas maltophilia isolated from gasoline-contaminated soil is capable of degrading methyl tert-butyl ether

Background: Methyl tert-butyl ether (MTBE) is a pollutant that causes deleterious effects on human and environmental health. Certain microbial cultures have shown the ability to degrade MTBE, suggesting that a novel bacterial species capable of degrading MTBE could be recovered. The goal of this study was to isolate, identify and characterize the members of a bacterial consortium capable of degrading MTBE. Results: The IPN-120526 bacterial consortium was obtained through batch enrichment using MTBE as the sole carbon and energy source. The cultivable fraction of the consortium was identified; of the isolates, only Stenotrophomonas maltophilia IPN-TD and Sphingopyxis sp. IPN-TE were capable of degrading MTBE. To the best of our knowledge, this report is the first demonstrating that S. maltophilia and Sphingopyxis sp. are capable of degrading MTBE. The degradation kinetics of MTBE demonstrated that S. maltophilia IPN-TD had a significantly higher overall MTBE degradation efficiency and rate (48.39 ± 3.18% and 1.56 ± 0.12 mg L-1 h-1, respectively) than the IPN-120526 consortium (38.59 ± 2.17% and 1.25 ± 0.087 mg L-1 respectively). The kinetics of MTBE removal by both cultures fit first-order and pseudo-first-order reaction models. Conclusions: These findings suggest that S. maltophilia IPN-TD in axenic culture has considerable potential for the detoxification of MTBE-contaminated water.

Decolorization of azo dyes (Direct Blue 151 and Direct Red 31) by moderately alkaliphilic bacterial consortium

Abstract Removal of synthetic dyes is one of the main challenges before releasing the wastes discharged by textile industries. Biodegradation of azo dyes by alkaliphilic bacterial consortium is one of the environmental-friendly methods used for the removal of dyes from textile effluents. Hence, this study presents isolation of a bacterial consortium from soil samples of saline environment and its use for the decolorization of azo dyes, Direct Blue 151 (DB 151) and Direct Red 31 (DR 31). The decolorization of azo dyes was studied at various concentrations (100–300 mg/L). The bacterial consortium, when subjected to an application of 200 mg/L of the dyes, decolorized DB 151 and DR 31 by 97.57% and 95.25% respectively, within 5 days. The growth of the bacterial consortium was optimized with pH, temperature, and carbon and nitrogen sources; and decolorization of azo dyes was analyzed. In this study, the decolorization efficiency of mixed dyes was improved with yeast extract and sucrose, which were used as nitrogen and carbon sources, respectively. Such an alkaliphilic bacterial consortium can be used in the removal of azo dyes from contaminated saline environment.

Remoción anaerobia del colorante azul directo brl en Reactor Anaerobio de Flujo Ascendente UASB (Upflow Anaerobic Sludge Blanket) con carbón activado / Anaerobic removal of the brl direct blue dye in Upflow Anaerobic Sludge Blanket (UASB) with activated carbon

En esta investigación se utilizó el colorante azul directo brl para remoción anaerobia con un consorcio bacteriano aislado de efluentes industriales del Parque Industrial río Seco (PIRS), Arequipa, Perú; en un reactor anaerobio de flujo ascendente UASB con carbón activado. El reactor tuvo una capacidad de 14.4 L con lodos y carbón activado del 40% de volumen, con una carga orgánica de 6 Kg DQO/m³•día y un tiempo de retención hidráulica de 1 día con un flujo ascendente. El objetivo fue medir la eficiencia de la remoción anaerobia del colorante en un tiempo de 28 días. Los resultados demostraron un incremento del 41% de los Sólidos Suspendidos Volátiles (SSV) de 12894 mg•L-1 a 21546 mg•L-1 bajo las condiciones del experimento, con una remoción del 57% de la Demanda Química de Oxigeno (DQO) de 484 mg•L-1 a 122 mg•L-1 y una remoción del 87% del colorante azul directo brl de 69.61 mg•L-1 a 9 mg•L-1. Los resultados con el carbón activado granular solamente, demostraron una remoción del 61% del colorante azul directo brl de 70.67 mg•L-1 a 27.83 mg•L-1 a los 28 días.

In this research the brl direct blue dye was used for anaerobic removal with a bacterial consortium of industrial effluents from Industrial Park Río Seco (IPRS), Arequipa, Peru; in an anaerobic reactor of UASB Upflow with activated carbon. The reactor had a capacity of 14.4 L with sludge and activated carbon of 40% of volume, with an organic load of 6 Kg COD/m³•dia and a hydraulic retention time of 1 day with an upward flow. The objective was to measure the efficiency of the anaerobic removal of coloring in a time of 28 days. The results showed an increase of 41% of the solids suspended volatile (SSV) 12894 mg•L-1 up to 21546 mg•L-1 under the conditions of the experiment, with a removal of 57% of the chemical demand of oxygen (COD) from 484 mg•L-1 to 122 mg•L-1 and a removal of 87% of the dye Blue direct the 69.61 brl mg•L-1 to 9 mg•L-1. Results with activated charcoal granular only, they showed a removal of 61% of the dye Blue direct 70.67 brl mg•L-1 to 27.83 mg•L-1 at 28 days.

Optimización del medio de cultivo QBP para la producción de biomasa del consorcio BIOYAF / Optimization of culture media QBP to the production of biomass of consortium BIOYAF

La optimización de los medios de cultivo con fines industriales en la mayoría de los casos ha sido efectuada mediante procedimientos empíricos de ensayo y error. Empleando diversos métodos estadísticos es probable que el medio de cultivo original pueda ser optimizado, en muchos casos es posible obtener un medio que no solo sea más productivo, sino de menor o igual costo que el original. Se optimizó el medio de cultivo QBP para el crecimiento de las cepas del consorcio bacteriano BIOYAF capaz de degradar hidrocarburos del petróleo, empleando un Diseño de Factor Categórico Individual para determinar el tiempo de trabajo, un Diseño Factorial (24) para determinar los rangos de trabajo de concentración de los nutrientes y un Diseño de Superficie de Respuesta para optimizar las concentraciones. Las variables de respuesta de evaluación de los experimentos fueron masa húmeda, masa (UDO), conteo de viables, conductividad, pH y tensión superficial. El tiempo óptimo para el crecimiento de las cepas del consorcio BIOYAF es de seis horas. El medio de cultivo QBP con concentraciones óptimas de fosfato de amonio (3,19 g.L-1), sulfato de magnesio (0,04 g.L-1), levadura (3,77 g.L-1) y sacarosa (47,89 g.L-1) permite que la producción de biomasa aumente de 1,540 UDO a 3,082 UDO.

The optimization of culture media with industrial purposes, in most cases, has been made through empirical trial and error procedures. Using different statistical methods original culture media can be optimized, in many cases, is possible to obtain a more productive media, at the same cost as the original one. The culture media QBP was optimized for the growth of the bacterial consortium BIOYAF, which can degrade petroleum hydrocarbons, using a Categorical Individual Factor Design to determine the working time, a Factorial Design (24) to determine working range of elements concentration and a Surface Response Design to optimize the concentrations. The response variables of the experiments used in this work were: wet mass, mass (UDO), viable's count, conductivity, pH and surface tension. The optimal time for growth of the consortium was of six hours. The optimized QBP culture media (ammonium phosphate: 3.19; magnesium sulphate: 0,04; yeast extract : 3,77; sucrose: 47,89) allowed that the biomass' production increases of 1,540 UDO to 3,082 UDO.

Consorcio microbiano nativo con actividad catalítica para remoción de índigo y surfactantes en agua residual industrial textil a través de una matriz de inmovilización / Microbial consortium native catalytically active for removal of indigo and surfactants in textile industry wastewater through an immobilization matrix

El siguiente estudio tuvo como objetivo aislar seis diferentes cepas bacterianas provenientes de las descargas de agua utilizadas en la tintura de hilo con colorante índigo, que tuviesen capacidad de degradación de compuestos orgánicos del tinte índigo y tres surfactantes de tipo no iónicos. Igualmente, se evaluaron diferentes medios de soporte para inmovilizar las cepas seleccionadas. Las cepas con mejor capacidad de decoloración se combinaron para conformar cuatro consorcios (I, II, III, y IV) con el fin de potenciar el proceso de decoloración, considerando que la sinergia y el complemento de actividades metabólicas de cultivos mixtos dentro de una comunidad microbiana incrementan la eficiencia de remoción de carga orgánica. Los porcentajes de remoción que se alcanzaron fueron 64, 73, 76 y 59 %, respectivamente. Los cultivos individuales no presentaron porcentajes de remoción superiores a los reportados por los consorcios, lo que permite pensar en su utilización para la remoción de tintes índigos en aguas residuales.

The aim of this study was isolate six different bacterial strains from water discharges used in dyeing yarn with indigo, capable of degradation of organic compounds with indigo dye and three type nonionic surfactants. Similarly, various supporting media were evaluated for immobilizing the selected strains. Strains with better capacity were combined to form four consortia (I, II, III, and IV) in order to enhance the bleaching process, whereas synergy and complement metabolic activities of mixed cultures within a community increase microbial removal efficiency of organic load. Removal percentages were achieved which were 64, 73, 76 and 59%, respectively. Individual cultures showed no higher than rates reported by consortia removal, which suggests in its use for the removal of indigo dyes in wastewater.

Effect of biologically treated petroleum sludge on seed germination and seedling growth of Vigna unguiculata (L.) Walp. (Fabaceae)

The present investigation was carried out to study the response of different concentrations of treated petroleum sludge on seed germination, root and shoot length and tolerance of Vigna unguiculata (L.) Walp. The biologically treated petroleum sludge with bacterial consortium showed 54.8% reduction in total petroleum hydrocarbons. Treated sludge was utilized with agricultural soil in known concentration for the assessment of growth of V. unguiculata. A remarkable absence of seed germination was observed at higher sludge concentration. The different concentrations of treated petroleum sludge showed severe decline on the length, weight and vigour index of the tested seedlings with increasing sludge concentrations. The results showed that the difference in rate of seed germination was significant among various concentrations. Under environmental stress condition, germination is the most critical phase of life cycle in crop plants. In this present study, the high oil content found to alter the osmotic relation between seed and water and thus reduce the amount of water absorbed. It was concluded that the concentration of nutrients and oil present in the treated sludge were toxic to the plant.

Degradation of 4-Chlorophenol by a Moderately Halophilic Bacterial Consortium under Saline Conditions.

Aims: To investigate the degradation of 4-chlorophenol by a moderately halophilic bacterial consortium and to study the effect of nitrogen sources on the degradation of 4- chlorophenol. Study Design: 4-chlorophenol degradation by moderate halophiles. Place and Duration of Study: Centre for Environmental studies, Microbiology Lab, Anna University, Chennai, Tamil Nadu, between Jan 2009 and May 2009. Methodology: 4-chlorophenol was degraded with the moderately halophilic bacterial consortium in the minerals salts medium and degradation was analysed by gas chromatography. Effect of NaCl concentrations and alternate nitrogen sources on the degradation of 4-chlorophenol was determined. Results: The bacterial consortium was able to degrade 4-Chlorophenol at a range of NaCl concentrations, where the optimum degradation was obtained at 50 g/L of NaCl. Addition of alternate nitrogen sources like tryptone and urea did not enhance the degradation of 4- Chlorophenol. Conclusion: Bacterial consortium degraded 4-chlorophenol at optimum NaCl concentration of 50 g/L of NaCl. Addition of yeast extract as nitrogen source showed higher degradation than the nitrogen sources.

Crecimiento de Casuarina equisetifolia (Casuarinaceae) en suelo con diésel, y aplicación de bioestimulación y bioaumentación / Casuarina equisetifolia (Casuarinaceae) growth in soil with diesel and application of biostimulation and bioaugmentation

Phytoremediation is an ecologically sound biotechnology directed to cleaning up contaminated soils. The study of tree species to treat petroleum contaminated soils is scarce; moreover, the combination of phytoremediation with bioaugmentation and biostimulation processes is also limited. Thus, this work evaluated the effects of the inoculation of Glomus intraradices, a bacterial consortium (M2BOS1-R2 and M2BOSI-F4) and Trichoderma viride, on the growth of Casuarina equisetifolia, fertilized with Floranid® or Triple 17, when sown in a diesel-contaminated soil (7 500mg/kg). The factorial experiment 2x5x3 included 30 treatments with 10 replicates in a completely randomized design under greenhouse conditions for 120 days. Diesel significantly diminished plant height, total biomass, and plant index quality (PIQ). Glomus or bacterial consortium significantly increased plant height, total biomass and PIQ when compared to the inoculation of the three microorganisms or to the control. Floranid had negative effects on plant growth and PIQ at diesel contamination. Fertilization with Triple 17 combined with the three microorganisms stimulated plant growth in the absence of diesel, whereas in the presence of this contaminant the treatments combining Triple 17 with the bacterial consortium or with Trichoderma had better plant growth and PIQ. Mycorrhizal colonization was inhibited due to diesel contamination, and especially when Floranid was applied. The fertilizer Triple 17 (biostimulation) combined with the beneficial microorganisms (bioaugmentation) improved growth responses of C. equisetifolia in diesel-contaminated soil.

La fitorremediación es una biotecnología ecológicamente racional que está dirigida a la limpieza de suelos contaminados; sin embargo, el estudio de especies arbóreas para la fitorremediación de suelos con hidrocarburos del petróleo es limitado. Más aún, la combinación de la fitorremediación con procesos de bioaumentación y bioestimulación es también limitada. Por lo anterior, este estudio evaluó el efecto de la inoculación de Glomus intraradices, un consorcio bacteriano (M2BOS1-R2 y M2BOSI-F4) y Trichoderma viride en el crecimiento de plantas de Casuarina equisetifolia L. fertilizadas con Floranid® o Triple 17, en suelo contaminado con diésel (7 500mg/kg). El experimento factorial 2x5x3 incluyó 30 tratamientos y 10 repeticiones, distribuidos completamente al azar en invernadero, durante 120 días. El diésel disminuyó significativamente la altura, la biomasa total y el índice de calidad (ICP) de planta. Glomus o las bacterias aumentaron significativamente la altura, la biomasa seca total y el ICP con respecto al tratamiento sin inocular o con la triple inoculación. El Floranid redujo el crecimiento vegetal y el ICP, en presencia de diésel. El Triple 17 combinado con los tres microorganismos produjo mayor crecimiento vegetal en ausencia de contaminación, pero en presencia de diésel, el Triple 17 combinado con bacterias o con Trichoderma, estimuló la biomasa seca total y el ICP. La colonización micorrízica fue inhibida por el diesel, especialmente con la fertilización del Floranid. El Triple 17 (bioestimulación) combinado con los microorganismos (bioaumentación), favoreció el crecimiento de Casuarina en suelo contaminado con diésel.

Microbial Biodegradation of Aromatic Compounds in a Soil Contaminated with Gasohol.

The studies developed in this work aimed to find alternatives to biodegradation or bioremediation of soils contaminated with gasoline or gasohol. So, the biodegradation of benzene, toluene and o-xylene (BTX) in soil samples contaminated with gasoline or gasohol by a bacterial consortium was studied. Four bacterial strains were selected for the consortium based on their growth capacity in gasoline, gasohol and BTX as sole carbon sources, and on the production of biosurfactants in mineral medium containing gasohol as the sole carbon source. The reduction of TX concentrations in soil slurries in a multi-cell bioreactor system was used as the criterion to evaluate biodegradation efficiency. BTX removal was highly stimulated by air injection and mineral nutrients, and was significantly increased by the presence of the bacterial consortium. Addition of a proprietary oxygen release compound did not stimulate the biodegradation of BTX.

Efecto de la inoculación de la cepa Sphingomonas paucimobilis 20006FA sobre la composición de un consorcio bacteriano degradador de fenantreno / Effect of the inoculant strain Sphingomonas paucimobilis 20006FA on the bacterial composition of a phenanthrene-degrading consortium

Se estudió el efecto de la inoculación con la cepa Sphingomonas paucimobilis 20006FA sobre la composición bacteriana de un consorcio degradador de fenantreno en cultivos discontinuos (batch) con 8 repiques sucesivos. El consorcio original se obtuvo a partir de un suelo prístino. A los fines del estudio, se obtuvieron y mantuvieron dos consorcios: uno inoculado (F200+I) y otro sin inocular (F200). Se estudió la diversidad bacteriana de los consorcios mediante el análisis de microorganismos cultivables (por caracterización fenotípica y genotípica) y totales (por PCR-DGGE). A lo largo de los repiques sucesivos pudo observarse en ambos consorcios una tendencia a la pérdida de la capacidad degradadora de fenantreno, acompañada por una disminución de la diversidad bacteriana. Si bien la inoculación no produjo cambios significativos en la capacidad degradadora de fenantreno de los consorcios (29,9% para F200 y 27,6% para F200+I hacia el tercer repique), sí produjo cambios en la composición bacteriana, ya que los perfiles de DGGE revelaron una dinámica estructural diferente en el consorcio inoculado. En ambos consorcios se pudo observar la presencia de una banda intensa posicionada a la misma altura que el ADN del inóculo en el gel de DGGE; sin embargo, los cultivos aislados de los consorcios que presentaban idéntica posición de banda en el perfil PCR-DGGE que la cepa S. paucimobilis 20006FA mostraron baja similitud con la cepa inoculada mediante la técnica de RAPD.

The effect of the inoculant strain Sphingomonas paucimobilis 20006FA on the bacterial composition of a phenanthrene-degrading consortium obtained from a pristine soil in sequencing batch cultures was studied. Inoculated (F200+I) and non-inoculated (F200) phenanthrene-degrading consortia, were obtained. Bacterial diversity of consortia was studied at cultivable (phenotype and genotype characterization) and non-cultivable (PCR-DGGE) levels. During the successive cultures, a loss in the phenanthrene-degrading capacity and a decrease in the bacterial diversity were observed in both consortia. Although inoculation did not produce any significant changes in the consortia phenanthrene-degrading capacity (29.9% F200 and 27.6% F200+I), it did produce changes in the bacterial composition, showing a differential structural dynamics in the DGGE profiles of the inoculated consortium. In both consortia, a dominant band placed at the same position as that of the DNA of the inoculant strain in the DGGE gel could be observed. However, isolated cultures from the consortia which had an identical band position to that of S. paucimobilis 20006FA in the PCR-DGGE profile showed low similarity with respect to the inoculant strain (RAPD).