Search

Currently, organochlorine pesticides (OPs) are restricted or banned from agricultural and public health areas. However, many of these compounds have been found in high concentrations in contaminated sites, and therefore continue to pose environmental and health concerns. Thus, it is imperative to identify efficient microorganisms to remove them and to develop methods to remediate environments contaminated with OPs. In this regard, the aim of this work was to evaluate the individual and simultaneous removal of three OPs; specifically lindane (LIN), γ-chlordane (CLD) and methoxychlor (MTX) (2 mg L-1 of each pesticide alone or as constituent of a mixture), from liquid contaminated systems, employing a native and non-GMO Streptomyces strain. Toxicity test of the treated systems against the cell line Caco-2, and the detection in the genome of the used microorganism of sequences related with the pesticides catabolism are reported. The results demonstrated that, Streptomyces sp. A5 was able to remove individually 57.4%, 100.0% and 6.5% of LIN, CLD and MTX, respectively. From the pesticide mixture, LIN and CLD were efficiently removed on 62.2% and 68.6% respectively by the studied strain. On the other hand, we demonstrated that the liquid systems contaminated with the OPs mixture and bioremediated with Streptomyces sp. A5 showed lower cytotoxicity than their respective controls without inoculate. Moreover, molecular studies revealed the presence in Streptomyces sp. A5 of putative lin genes with potential dehydrochlorinase, haloalkane dehalogenase and NAD-dependent dehydrogenase activities. Therefore, the potential of Streptomyces sp. A5 to efficiently remediate OPs alone or in mixtures from liquid contaminated system, was demonstrated. Fil: Fuentes, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Sineli, Pedro Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Pons, Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: de Moreno, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Benimeli, Claudia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Hill, Russell T.. University of Maryland; Estados Unidos Fil: Cuozzo, Sergio Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

With the aim of comparing the behavior of single and mixed cultures of actinobacteria for the removal of chromium and lindane from different co-contaminated systems, the actinobacteria Streptomyces sp. M7, MC1, A5 and Amycolatopsis tucumanensis DSM 45259 were assayed as simple, double, triple, and quadruple cultures in minimal medium and soil artificially polluted with Cr(VI) and lindane. In liquid medium, Streptomyces sp. MC1 and the quadruple consortium reached the highest Cr(VI) and lindane removal (94% and 52%, respectively, in both cultures), although they did not present statistically significant differences in Cr(VI) removal respect to six other consortia. The best removal of bioavailable chromium and lindane from artificially contaminated soil were achieved by Streptomyces sp. M7 (50% and 60%, respectively) and the quadruple consortium (60% and 55%, respectively). The bioassay with Lactuca sativa demonstrated the success of the bioremediation in soil by Streptomyces sp. M7 and the quadruple consortium through an increase in the vigor index measured in lettuce seedlings compared to non-treated soil. The quadruple consortium demonstrated to be appropriate to bioremediate Cr(VI) and lindane co-contaminated both liquid and soil systems. The viability of the four strains after the bioremediation process was confirmed. These results represent an approximation for conducting a field-scale bioremediation strategy. Fil: Aparicio, Juan Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Sáez, Juliana María. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Raimondo, Enzo Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Benimeli, Claudia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Polti, Marta Alejandra. Universidad Nacional de Catamarca; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

The textile dyeing and other industries use an extensive amount of azo dyes. Their effluents are specifically colored and could cause severe damage to the environment. The anaerobic treatment of textile dying effluents could generate carcinogenic aromatic amines. For this reason, in the recent years yeasts have become a promising alternative, combining unicellular growth with oxidative mechanisms. This work reports the oxidative Reactive Black 5 (RB5) biodegradation mechanism by Trichosporon akiyoshidainum HP 2023, isolated from a non-contaminated environment and extensively studied for its exceptional decoloration abilities on azo dyes. Several analytical techniques (HPLC, FTIR, GC–MS, UV–vis) were used as to monitor the dye-decoloration process and the enzyme produced during biodecoloration. Starting with 200 mg L−1 of RB5, at 12 h, 89% color removal and a shift from dark blue to purple was observed, at 24 h no color was visible. Also, a decrease of aromatic amines and total aromacity (71 and 75%, respectively) was observed and biomass presented no color. The mechanism is driven by phenol oxidase and peroxidase enzymes, as they were no present in cultures without dye. During decoloration, at 15 h both enzymes reached it maximum activity levels, 353 UL−1 for phenol oxidase and 2750 UL−1 for peroxidase. The two-stages proposed mechanism involves the formation of a purple-colored quinone with an azo bond, which is subsequently degraded, finally the complete disappearance of color is achieved. These results make Trichosporon akiyoshidainum HP 2023 a promising tool for dye removal treatment of colored textile effluents. Fil: Martorell, María Martha. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Pajot, Hipolito Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Castellanos, Lucia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

Wastewaters containing polycyclic aromatic hydrocarbons (PAH) must be treated before discharge in water bodies to avoid environmental pollution and comply with environmental protection regulations. The development of novel PAH removal technologies from wastewaters is thus of great importance. The aim of this work was to use immobilized bacteria on polyurethane foam (PUF) for acenaphthene, fluoranthene and pyrene removal using annonaceous acetogenins (ACG) to stimulate biofilm and possibly enhance PAH removal activity. Different ACG were tested for their capacity to stimulate biofilm formation on Pseudomonas monteilii P26, a known naphthalene degrader. Itrabin, jetein and an ethanolic extract of Annona cherimola pulp were selected for showing a high stimulation level at low concentration in microplate biofilm formation assay. On PUF, the biofilm formation was strongly stimulated by itrabin and the ethanolic extract. However, there was no difference between the PAH removal percentages of the different systems (sterile PUF, cell immobilized in presence of ACG and cells immobilized without ACG). In average, 99% acenaphthene, 98% fluoranthene and 92.5% pyrene were removed in 7 days mostly by sorption (initial PAH concentration was 50 ppm). A 15–22% removal was attributed to biodegradation or bioaccumulation in the systems with immobilized cells. In this case, stimulating biofilm formation did not enhance PAH removal by immobilized bacteria on PUF. Fil: Alessandrello, Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentina Fil: Parellada, Eduardo Alberto. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentina Fil: Neske, Adriana Neske. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vullo, Diana Lia. Universidad Nacional de General Sarmiento. Instituto de Ciencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ferrero, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina