Search

Background: Brewers spent grain (BSG) is one of the most abundant by-products of the beer industry and causes serious environmental problems. Ferulic acid (FA) is an antioxidant with potential cosmeceutical applications. FA was extracted from BSG, developing a method of high extraction performance in order to be encapsulated in ultradeformable liposomes (Nanoferulic. NF).Objectives: To obtain a product with high added value such as FA, from a residue currently underused, using simple and economical chemical methods. To load FA into a nanosystem designed for the topical route; its encapsulation has the purpose to take profit from its photoprotective, anti-inflammatory and antioxidant properties in the deep layers of the skin. Methods: FA was obtained from dried BSG using acid and basic treatments in series. NF was prepared by lipid film resuspension of a solution containing FA obtained from BSG. Size and Z-potential were determined. Cytotoxicity was assessed in vitro. Skin penetration was assessed by NF determination at different skin depths and by confocal microscopy.Results: The yield of the extraction process was 0.43% on a dry basis. Encapsulation rendered liposomes of around 140 nm with 92% of encapsulation efficiency. No toxicity was observed in all the tested concentrations. Successful results were obtained from the regeneration studies.Conclusions: It was possible to develop a nanosystem containing FA, generating a high-value commercial input for the pharmaceutical and cosmeceutical industry. The use of BSG generated in industrial-scale would help to reduce the volume of highly polluting waste. Fil: Bucci, Paula Lorena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Santos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; Argentina Fil: Martinetti Montanari, Jorge Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB; Argentina Fil: Zaritzky, Noemi Elisabet. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina

Phenol is one of the contaminants most frequently found in the environment and it is considered a priority pollutant due to their toxic effects. Hairy roots (HR) constitute a good model tool for the removal of this contaminant. In this work, phenol removal using wild type (WT) and double transgenic (DT) Nicotiana tabacum HR was performed with high efficiency (60–80%, for 25–250 mg L−1 phenol solutions, respectively). After phytoremediation process, the toxicity of post removal solutions (PRS) was evaluated through two-toxicity test belonging to two trophic levels, Lactuca sativa test and Rhinella arenarum (AMPHITOX). Toxicity of PRS showed variable results since these solutions were less toxic to L. sativa seeds compared to R. arenarum embryos, which could be attributed to different sensitivities of the exposed organisms. Although PRS obtained using WT and DT HR reduced phenol phytotoxicity on L. sativa seeds, WT PRS were even less toxic than DT PRS according to this test. Regarding AMPHITOX, HR culture medium without phenol but incubated with HR and phenol PRS exerted a toxic effect on the embryos, which could be related to the presence of toxic products derived from HR metabolism. The results demonstrated that an efficient phenol removal is not always accompanied by a considerable reduction of the solution toxicity and therefore, the use of organisms from different trophic levels to evaluate the toxicity after the removal process gains importance. Fil: Paisio, Cintia Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina Fil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina Fil: González, Paola Solange. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Cordoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina

Old Yellow Enzymes play key roles in several cellular processes and have become an important family of enzymes withbiotechnological potential. One of the major challenges of biotechnology consists of the bioremediation of co-polluted soilswith organic and inorganic compounds. In co-contaminated areas, chromium normally exists in its more toxic and carcinogenicform Cr(VI). Microorganisms can reduce this metal to the insoluble and less toxic Cr(III).Streptomycessp. M7 is a strain able toefficiently bioremediate polluted soils withγ-hexachlorocyclohexane and Cr(VI). The complete degradation pathway for γ-hexachlorocyclohexane was recently elucidated in this strain. In the present work, we confirmed the ability ofStreptomycessp.M7 to eliminate a high percentage of Cr(VI) from a synthetic culture medium. After a transcriptional study in the presence ofCr(VI), we also report the molecular cloning of a gene coding for an Old Yellow Enzyme with chromate reductase activity. Ourresults suggest that the elimination of Cr(VI) byStreptomycessp. M7 is directly related to the activity of this Old Yellow Enzyme.The importance of our work is in identifying for the first time an Old Yellow Enzyme with chromate reductase activity inStreptomycesand Actinobacteria. Finding this enzyme helps understand chromium homeostasis inStreptomycessp. M7, inaddition to opening a new research window related to Old Yellow Enzymes from Actinobacteria. Fil: Sineli, Pedro Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Guerrero, Daiana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina Fil: Alvarez, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Dávila Costa, José Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

Vinasse, the most important liquid residue of the bioethanol production, is often used in fertigation programs. However, this practice may have negative effects on crops if applied without a prior conditioning treatment. In the present study, the efficiency of a fungus-based process as a method for vinasse treatment was evaluated. Phytotoxicity of the residue, before and after biological treatment, was tested on two plant species used for human consumption (Triticum aestivum L. and Raphanus sativus) in order to evaluate the application of vinasse in fertigation. The fungus, identified as Aspergillus sp. V2, showed high tolerance to vinasse, resulting in an optimal growth even when is cultivated on the undiluted residue. Biologically treated vinasse with a cycle of re-inoculation of spores resulted in a COD removal of 52%, whereas pH was increased from 4.4 to 6.1 at the end of treatment. Toxicity studies demonstrated a substantial improvement in the growth parameters (vigor index and fresh weight) of plant species exposed to treated vinasse compared to those exposed to raw residue. These results show that Aspergillus sp. V2 is useful for the recovery of an actual wastewater like sugarcane vinasse, enhancing its fertilizing properties. Fil: Rulli, Macarena María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Villegas, Liliana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; Argentina Fil: Colin, Veronica Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

Cross-linked oxalic acid/chitosan hydrogels (ChOxb) were synthesized, characterized and tested for the adsorption of azo-dyes (Reactive Red 195 RR195) in contaminated wastewater; this novel biodegradable material was highly efficient. SEM-EDS and N2 adsorption/desorption were used to analyze specific area; FTIR-ATR spectra evidenced electrostatic interactions between protonated amino groups of chitosan and oxalate ions (intensity decrease and shift of amide-II band). Adsorption performance in batch assays showed a maximum percentage of removal of 90.6%, at pH = 4 (initial dye concentration of 300 mg.L−1). The maximum adsorption capacity (Qm) at pH = 4 was 110.7 mg.g−1, positioning ChOxb as one of the most efficient adsorption materials. Oxalic acid (natural organic acid) is an eco-friendly cross-linking agent that reduced swelling and improved chemical stability of ChOxb at low pH = 2.5. Redlich-Peterson adsorption isotherm presented the best fit; adsorption thermodynamic parameters were evaluated. Mixed surface reaction and diffusion-controlled kinetic model was the equation that best fitted kinetic data. FTIR-ATR, SEM-EDS and Z-potential showed electrostatic interactions between dye and amino groups of ChOxb; ChOxd can be reused without losing adsorption capacity and competitive electrostatic interactions between ChOxb-nitrate were observed. This new bio-material is an excellent alternative for the removal of RR195, improving Qm with better structural and functional properties. Fil: Perez Calderon, John Freddy. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Santos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; Argentina Fil: Zaritzky, Noemi Elisabet. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ingenierí­a. Departamento de Ingeniería Química; Argentina

Se releva el panorama de la bioenergía en Argentina, y sus aplicaciones térmicas y eléctricas. Se analizan los avances en experiencias de acondicionamiento de biomasa sólida en forma de pellets, chips y carbón. Se mencionan algunos aprovechamientos energéticos mas destacables del país, que dan cuenta de la diversidad de recursos, pero aún señalan aspectos técnicos, tecnológicos y logísticos que deben ser resueltos. En particular, grandes emprendimientos cuentan con importación de tecnología y es escasa la producción nacional. Fil: Manrique, Silvina Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentina Fil: Salvo, Aien Weni. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentina Fil: Villafañe, Florencia. Gobierno de la Provincia de Jujuy. Ministerio de Ambiente; Argentina Fil: Martín, José Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Ambiente, Hábitat y Energía; Argentina Fil: Honorato, Martín Omar. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur; Argentina

Trichoderma fungi are considered as suitable biofertilizers, since they could increase the efficiency of the use of nutrients in plants and are used as biocontrol agents against plant pathogen. The aim of this study was to characterize a set of Trichoderma strains isolated from horticultural and near-pristine soils from the Argentine Pampas, and to evaluate their potentiality as a growth promoter and as a biocontroller of Fusarium wilt disease on tomato. Nineteen collected strains, identified as T. brevicompactum, T. gamsii and T. harzianum, were tested for their ability to produce the auxin indole 3-acetic acid (IAA), solubilize phosphate and biocontrol F. oxysporum. Twelve strains reduced growth of pathogenic fungus over 50% and four of them (named FCCT 16, FCCT 58, FCCT 199-2 and FCCT 363-2) exhibited IAA highest production (ranging 13.38–21.14 µg/ml) and were able to solubilize phosphate (ranging 215.80–288.18 µg/ml of calcium phosphate). Tomato plants inoculated with those four strains increased chlorophyll content, shoot length, fresh and dry weight of shoot and roots, and reduced F. oxysporum wilt disease between 10 and 30%. On the basis of our results, we conclude that soils of the Argentine Pampas harbor Trichoderma strains with beneficial dual effects which could be of interest for the development of commercial products. Fil: Bader, Araceli Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentina Fil: Salerno, Graciela Lidia. Fundación para Investigaciones Biológicas Aplicadas; Argentina Fil: Covacevich, Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentina Fil: Consolo, Verónica Fabiana. Fundación para Investigaciones Biológicas Aplicadas; Argentina

Dairy effluents contain limited nitrogen for biological treatment. In the present study a cheese whey wastewaterwas supplemented with ammonia to obtain suitable COD:N ratios. The effects of the organic load and micronutrientson the biological nitrogen removal process were analyzed in aerobic granular sequential batch reactors(SBRs). Better nitrifying activity (5.04 mg N.(L.h)−1) was achieved at COD:N = 100:12, when micronutrientswere added. In this condition, simultaneous nitrification- denitrification led to a higher inorganic nitrogen removal.Aerobic denitrification was driven by intracellular glycogen. In absence of micronutrients, nitrificationtook place when the organic load was decreased (COD:N = 100:22). The microbial community was analyzed bynext-generation sequencing technology. Nitrification was attributed to heterotrophic nitrifiers. Bacteria belongingto Niabella and Diaphorobacter genera and to Planctomycetales order are the main candidates responsiblefor the nitrification process. Co-treatment of dairy and ammonium-rich wastewater constitutes a promisestrategy for the biological treatment of dairy wastewaters. Fil: Bucci, Paula Lorena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Coppotelli, Bibiana Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Morelli, Irma Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Zaritzky, Noemi Elisabet. Universidad Nacional de La Plata. Facultad de Ingeniería; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Caravelli, Alejandro Horacio. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina

Non-viable biomass of Pseudomonas putida immobilized in agar-agar was used as adsorbent to remove aluminum from aqueous solutions. In batch assays, adsorption equilibrium was reached after 45 min and 95% of 2.7 mg/L Al3+ were adsorbed. Immobilized biomass was packed to obtain a fixed-bed column and the dynamic behavior in continuous mode was established through breakthrough curves. At different flow rates (0.5 and 1.0 mL/min) the adsorption capacity of the column did not change, but removal percentage was higher at the lowest flow rate (64.92% and 44.34%, respectively). The fixed-bed column presented a higher biosorption capacity than that obtained in batch experiments (0.15 and 0.09 mg Al3+/g beads, respectively), and showed stability for up to 12 successive adsorption/desorption cycles with negligible loss in adsorption efficiency. We concluded that this packed biosorbent could be a good alternative for the removal of Al3+ from aqueous solutions. Fil: Boeris, Paola Sabrina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Liffourrena, Juan Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina Fil: Lucchesi, Gloria Ines. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The present study was aimed to test an electrochemical sensing approach for the detection of an active chemolithotrophic metabolism (and therefore the presence of chemolithotrophic microorganisms) by using the corrosion of pyrite by Acidithiobacillus ferrooxidans as a model. Different electrochemical techniques were combined with adhesion studies and scanning electron microscopy (SEM). The experiments were performed in presence or absence of A. ferrooxidans and without or with ferrous iron in the culture medium (0 and 0.5 g L−1, respectively). Electrochemical parameters were in agreement with voltammetric studies and SEM showing that it is possible to distinguish between an abiotically-induced corrosion process (AIC) and a microbiologically-induced corrosion process (MIC). The results show that our approach not only allows the detection of chemolithotrophic activity of A. ferrooxidans but also can characterize the corrosion process. This may have different kind of applications, from those related to biomining to life searching missions in other planetary bodies. Fil: Saavedra Olaya, Albert Ulises. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina Fil: Figueredo, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina Fil: Corton, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina Fil: Abrevaya, Ximena Celeste. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina

Aim: To analyze the physiological response of Sphingobium sp. 22B to water stress. Methods and results:The strain was grown under excess of carbon source and then submitted to low (60RH) and high (18RH) water stress conditions for 96 h. Quantification of trehalose, glycogen, polyhydroxybutyrate (PHB), and transmission electron microscopy (TEM) was studied. Genes linked with desiccation were searched in Sphingobium sp. 22B and Sphingomonas "sensu latu" genomes and their transcripts were quantified by Real-Time PCR. Results showed that, in absence of water stress, strain 22B accumulated 4.76± 1.41% of glycogen, 0.84± 1.62% of trehalose and 44.9± 6.4% of PHB per cellular dry weight. Glycogen and trehalose were mobilized in water stresses conditions, this mobilization was significantly higher in 60RH in comparison to 18RH. Gene treY was upregulated 6-fold change in 60RH relative to 18RH. TEM and quantification of PHB revealed that PHB was mobilized under 60RH condition accompanied by the downregulation of the phbB gene. TEM images showed an extracellular amorphous matrix in 18RH and 60RH. Major differences were found in the presence of aqpZ and trehalose genes between strain 22B and Sphingomonas genomes. Conclusion: Strain 22B showed a carbon conservative metabolism capable of accumulation of three types of endogenous carbon sources. The strain responds to water stress by changing the expression pattern of genes related with desiccation, formation of an extracellular amorphous matrix and mobilization of the carbon sources according to the degree of water stress. Trehalose, glycogen and PHB may have multiple functions in different degrees of desiccation. The robust endowment of molecular responses to desiccation shown in Sphingobium sp. 22B could explain its survival in semiarid soil.Significance and Impact of the studyUnderstanding the physiology implicated in the toleration of the PAH-degrading strain Sphingobium sp 22B to environmental desiccation may improve the bioaugmentation technologies in semiarid hydrocarbons contaminated soils., Centro de Investigación y Desarrollo en Fermentaciones Industriales

The Northwest of Argentina has numerous sugar industries and about 99.5% of the total sugar production is concentrated in the provinces of Tucumán, Salta, and Jujuy. Integrated sugarcane factories (sugar mills coupled to a bioethanol distillery) are common in our country. The liquid fraction generated from rectification and distillation operations of bioethanol, known as vinasse, is not itself a hazardous waste, but because of its complex composition, it is considered potentially dangerous. The province of Tucumán has achieved a substantial improvement with regard to the vinasse spills onto watercourses near sugar-alcohol industries. However, millions of liters of effluent are annually accumulated in open-pit pools to the limit of their capacity, threatening the sustainability of the ecosystem. A variety of physicochemical and microbiological technologies is continually evaluated to mitigate the environmental impact of vinasse. However, microbiological conditioning of distillery effluents has been reported as effective and eco-friendly. Particularly, fungal technology has made great contributions to the treatment of vinasse since fungi possess an extraordinary ability to digest complex waste materials. Additionally, fungus-based processes offer the possibility to obtain value-added products from waste materials. The present chapter provides an overview of the current scope of fungal technology applied for treatment of vinasse. Additionally, are discussed the first advances on the potential of an autochthonous fungus strain to degrade a local sugarcane vinasse sample. Fil: del Gobbo, Luciana Melisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán; Argentina Fil: Colin, Veronica Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

Living organisms are subject to different environmental effects, including physical, biological or chemical factors. In front of pollution, which can be defined as an aggression, the organisms must be adapted to survive. In microsomal fraction of cells, there is an oxidase enzymatic complex, whose central element is the cytochrome P450, able to eliminate certain harmful substances. The main action of P450 system is to introduce a functional group to foreign lipophilic compound, which deveins water-soluble and it excretion was facilitated. In this study a method, originally designed to measure P450 activity in animal cells, was modified and adapted for application in plant cells from contaminated environments. Scindapsus aureus also namely Epipremnum aureum, is considered between the best plants with air purification ability. The aim of this work was to study the effect of polluted environments on this plant species, to determining its potential use as contamination biomarker. The results indicated that P450 activity was manifested only in saturated cell-free extract dialysates from those plants exposed to high contamination during periods longer than 30 days. The induction of this enzyme, with detoxificant power, could depend of pollutant type, and/or exposure times. Few studies using plants as air contamination biomarker by CO were conducted. The results obtained allow recommend susceptible species for quantifying indirect pollution in offices, laboratories, factories, where the workers are exposed 8 h daily, during several years. Fil: Cruz, Rosa Magdalena. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Salud Publica; Argentina Fil: Fuentes de Curia, Maria Elena. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Salud Publica; Argentina Fil: Khouri, Eduardo Alejandro. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Salud Publica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rollan, Graciela Celestina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Gonzalez, Silvia Nelina. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Salud Publica; Argentina

Faced with more and more stringent regulations, nowadays heavy metals are the environmental priority pollutants and are becoming one of the most serious environmental problems. A variety of remediation technologies are currently available to address these classes of pollutants (Fu and Wang 2011; Yao et al. 2012). However, many of they have several disadvantages such as a high cost and the risk of secondary contamination (de Souza et al. 2013). In this context, new technologies for the reduction of heavy metals to acceptable levels but at more manageable costs are continually being evaluated. Fil: Colin, Veronica Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Polti, Marta Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina Fil: Amoroso, Maria Julia del R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Fungi produce pigments and acids, generating particular local conditions which modify the physicochemical properties of materials. The aims of this work are (i) to investigate bioadhesion, foxing production and biofilm formation by Scopulariopsis sp. and Fusarium sp. isolated from document collections under laboratory conditions; (ii) to verify attack on cellulose fibres and (iii) to study the possibility of reducing fungal growth using natural products. Biofilm formation and extracellular polymeric substance (EPS) production by fungi were demonstrated in laboratory assays and by scanning electron microscopy (SEM) observations. The biocidal activity of two essential oils of Origanum vulgare L. and Thymus vulgaris L. was evaluated using the microatmosphere method. SEM observations showed that these strains were able to attach to paper and form biofilms, causing damage on them, which demonstrates the biodeterioration ability of these microorganisms. Scopulariopsis sp. and Fusarium sp. isolated from paper books showed the formation of fox-like reddish-brown colour spots, attack to the paper structure and pigment production on aged paper samples. The strains tested produced a decrease in the pH of one unit. This would substantiate the effect of the strains in paper biodeterioration. The microatmosphere method showed that volatile compounds of the essential oils have antifungal activity., Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Facultad de Ciencias Veterinarias, Facultad de Ciencias Naturales y Museo

Bloom-forming cyanobacteria are widely distributed in freshwater ecosystems. To cope with salinity fluctuations, cyanobacteria synthesize compatible solutes, such as sucrose, to maintain the intracellular osmotic balance. The screening of cyanobacterial genomes revealed that homologues to sucrose metabolism-related genes only occur in few bloomforming strains, mostly belonging to Nostocales and Stigonematales orders. Remarkably, among Chroococcales and Oscillatoriales strains, homologues were only found in M. aeruginosa PCC 7806 and Leptolyngbya boryana PCC 6306, suggesting a massive loss of sucrose metabolism in bloomforming strains of these orders. After a complete functional characterization of sucrose genes in M. aeruginosa PCC 7806, we showed that sucrose metabolism depends on the expression of a gene cluster that defines a transcriptional unit, unique among all sucrose-containing cyanobacteria. It was also demonstrated that the expression of the encoding genes of sucrose-related proteins is stimulated by salt. In view of its ancestral origin in cyanobacteria, the fact that most bloom-forming strains lack sucrose metabolism indicates that the genes involved might have been lost during evolution. However, in a particular strain, like M. aeruginosa PCC 7806, sucrose synthesis genes were probably regained by horizontal gene transfer, which could be hypothesized as a response to salinity fluctuations. Fil: Kolman, Maria de Los Angeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentina. Fundación para Investigaciones Biológicas Aplicadas; Argentina Fil: Salerno, Graciela Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentina. Fundación para Investigaciones Biológicas Aplicadas; Argentina

La quitina es el polisacárido constitutivo más abundante en los exoesqueletos de insectos y crustáceos. Su derivado más tradicionalmente estudiado es el quitosano. En el presente trabajo se ha propuesto la obtención de quitina y la utilización de quitosano para el desarrollo de películas con potencial uso de aplicación en agricultura. La quitina fue obtenida a partir del desecho de exoesqueletos de langostinos asociados a su comercialización de las industrias pesqueras de la ciudad de Mar del Plata, Argentina. Si bien existen varios métodos de obtención de quitina, en el presente trabajo se utilizó una metodología sencilla en el laboratorio pero de fácil escalonamiento a escala piloto. Esta consistió en un proceso químico de hidrolisis de las proteínas y remoción del material inorgánico utilizando ácidos y álcalis a altas concentraciones pero, a diferencia de la mayoría de los métodos descriptos, el procedimiento se realiza a temperatura ambiente. Para la obtención de películas o filmes se partió de quitosanos de origen comercial y se utilizó la técnica de evaporación de solvente conocida como casting, descripta como altamente práctica y sencilla. Se optimizaron las condiciones para la utilización de dichos filmes en el recubrimiento de semillas de trigo. Fil: Casalongue, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: Civantos, Ana. Universidad Complutense de Madrid; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: López Lacomba, Juan Luis. Universidad Complutense de Madrid; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: Mansilla, Andrea Yamila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: Martínez Campos, Enrique. Universidad Complutense de Madrid; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: Mendieta, Julieta Renee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina Fil: Ramos, Viviana. Universidad Complutense de Madrid; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina

Many of the complex issues worldwide regarding environmental management and sustainable develo-pment require integrating the social and natural sciences. Nevertheless, while theoretical discussions have been increasingly developed, operative issues are still major barriers to integrated social-ecological analysis. The aim of this paper was to assess regional forage production in semi-arid rangelands as a key feature in social-ecological analysis, by using human organizational units (i.e. counties). We used these state-administrative units to explore demographic and farming indicators in order to address socio-productive implications of different regional forage production dynamics. We studied the forage spatial and temporal dynamics in two different large ecological regions: Monte and Patagonia, under a single administrative unit (i.e. province). Since forage production estimations in arid rangelands are not trivial, we tested two different methods. We found that inter-annual variability in forage production explained the main differences between regions. At a regional level, zones with higher temporal variability in forage production registered less rural residents and farm numbers, but inverse situations were registered at sub-regional scales. We found a non-linear relationship between forage production variability and rural population density. We proposed differentiated policy recommendations regarding rangeland management and animal husbandry, considering both the social and ecological contexts. © 2012 Elsevier Ltd. Fil: Easdale, Marcos Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; Argentina Fil: Aguiar, Martin Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina

The Copahue geothermal system is a natural extreme environment located at the northern end of the Cordillera de los Andes in Neuquén province in Argentina. The geochemistry and consequently the biodiversity of the area are dominated by the activity of the Copahue volcano. The main characteristic of Copahue is the extreme acidity of its aquatic environments; ponds and hot springs of moderate and high temperature as well as Río Agrio. In spite of being an apparently hostile location, the prokaryotic biodiversity detected by molecular ecology techniques as well as cultivation shows a rich and diverse environment dominated by acidophilic, sulphur oxidising bacteria or archaea, depending on the conditions of the particular niche studied. In microbial biofilms, found in the borders of the ponds where thermal activity is less intense, the species found are completely different, with a high presence of cyanobacteria and other photosynthetic species. Our results, collected during more than 10 years of work in Copahue, have enabled us to outline geomicrobiological models for the different environments found in the ponds and Río Agrio. Besides, Copahue seems to be the habitat of novel, not yet characterised autochthonous species, especially in the domain Archaea., This work was partially supported by grants PICT 2012-0623 and PICT 2013-0630 (ANPCYT)., We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).

Copahue is a natural geothermal field (Neuquén province, Argentina) dominated by the Copahue volcano. As a consequence of the sustained volcanic activity, Copahue presents many acidic pools, hot springs and solfataras with different temperature and pH conditions that influence their microbial diversity. The occurrence of microbial biofilms was observed on the surrounding rocks and the borders of the ponds, where water movements and thermal activity are less intense. Microbial biofilms are particular ecological niches within geothermal environments; they present different geochemical conditions from that found in the water of the ponds and hot springs which is reflected in different microbial community structure. The aim of this study is to compare microbial community diversity in the water of ponds and hot springs and in microbial biofilms in the Copahue geothermal field, with particular emphasis on Cyanobacteria and other photosynthetic species that have not been detected before in Copahue. In this study, we report the presence of Cyanobacteria, Chloroflexi and chloroplasts of eukaryotes in the microbial biofilms not detected in the water of the ponds. On the other hand, acidophilic bacteria, the predominant species in the water of moderate temperature ponds, are almost absent in the microbial biofilms in spite of having in some cases similar temperature conditions. Species affiliated with Sulfolobales in the Archaea domain are the predominant microorganism in high temperature ponds and were also detected in the microbial biofilms. Fil: Urbieta, María Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales. Universidad Nacional de la Plata. Facultad de Cs.exactas. Centro de Investigación y Desarrollo En Fermentaciones Industriales; Argentina Fil: Gonzalez Toril, Elena. Consejo Superior de Investigaciones Cientificas; España Fil: Aguilera Bazán, Ángeles. Consejo Superior de Investigaciones Cientificas; España Fil: Giaveno, María Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - Patagonia Norte. Instituto de Investigación y Des. En Ing. de Procesos, Biotecnología y Energias Alternativas. Idepa - Subsede San Antonio Oeste; Argentina Fil: Donati, Edgardo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales. Universidad Nacional de la Plata. Facultad de Cs.exactas. Centro de Investigación y Desarrollo En Fermentaciones Industriales; Argentina

Background: The Fogarty International Center (FIC) of the United States National Institutes of Health includes the International Training and Research in Environmental and Occupational Health (ITREOH) Program. The "International Training Program in Environmental Toxicology and Public Health" Center, funded in 2002 is based at the University of California, Davis, and is part of the ITREOH group of Centers. It has major efforts focused at the public universities in Montevideo, Uruguay, and Salta, Argentina. Results: Training and research efforts in Salta begun in 2005 in the College of Engineering. A donated used real-time PCR machine was the starting point and the initial FIC support was instrumental to face other problems including physical space, research projects and grants, trainees, training, networking, and distractions/opportunities in order to develop local capacities in Environmental Engineering using modern methodology. After 6 years of successful work, the Salta center has become a reference Center in the field, and is still growing and consolidating. Conclusions: This program has had a significant impact locally and regionally. The model used in Argentina could be easily adapted to other fields or types of projects in Argentina and in other developing countries. Fil: Rajal, Verónica Beatriz. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina Fil: Cid, Alicia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina Fil: Cruz, Mercedes Cecilia. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina Fil: Poma, Hugo Ramiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina Fil: Gutiérrez Cacciabue, Dolores. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina Fil: Romano Armada, Neli. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina Fil: Moraga, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina. Universidad Nacional de Salta. Facultad de Ingeniería; Argentina Fil: Last, Jerold A.. University of California; Estados Unidos

Chromate-resistant microorganisms able to reduce toxic Cr(VI) into insoluble Cr(III) are seen as prom- ising candidates for alleviating Cr(VI)-contamination. In this study, chromate-reducing yeasts could be isolated from a textile-dye effluent and associated biofilm by using microcosm methodology with pe- riodical 1 mM Cr(VI)-pulses. Viable cell count seemed to reveal a progressive tolerance increase to Cr(VI). However, fungal colony numbers decreased after 108 h of cultivation most likely as a consequence of the accumulated toxic effects of metal during enrichment. From 49 different Cr(VI)-tolerant fungal mor- photypes isolated under selective conditions, 12 yeasts showed resistance up to 50 mM and 6 fila- mentous fungi up to 2 mM. These highly tolerant yeasts could be subsequently grouped into 8 OTUs (Operational Taxonomic Units) according to the ITS1-NL4 RFLP (Restriction Fragment Length Polymor- phism) analysis. From them, microsatellite amplification, sequencing and Cr(VI)-removal ability allowed to select two representative isolates. A polyphasic approach including morphological, physiological/ biochemical characterization and molecular taxonomy analysis allowed to identify these isolates as Cyberlindnera jadinii M9 (previously Pichia jadinii) and Wickerhamomyces anomalus M10 (previously Pichia anomala). Cy. jadinii M9 and W. anomalus M10 were grown in YNB’ medium plus 1 mM Cr(VI) at 25 C and pH 5.0, causing complete chromium removal before reaching 48 h of cultivation. Flame Atomic Absorption Spectroscopy (FAAS) assays suggested that Cr(VI) withdrawal was coupled to Cr(III) appearance. Electron microscopy studies indicated absence of precipitates on the cell wall region or microprecipitates into the cellular cytoplasm. These complementary results revealed that biospeciation to Cr(III) would the main detoxification mechanism in selected chromate-resistant yeasts, which could be thus envisaged as promising tools for future biological treatment of Cr(VI) pollution. Fil: Fernandez, Pablo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina; Fil: Cabral, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina; Fil: Delgado, Osvaldo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina; Fil: Fariña, Julia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina; Fil: Figueroa, L.I.C.. Universidad Nacional de Tucuman. Facultad de Bioquimica, Quimica y Farmacia; Argentina

Microcosm assays with dye-amended culture media under a shot-feeding strategy allowed us to obtain 100 yeast isolates from the wastewater outfall channel of a dyeing textile factory in Tucuman (Argentina). Meanwhile, 63 yeast isolates were obtained from Phoebe porphyria (Laurel del monte) samples collected from Las Yungas rainforest (Tucuman), via a classical isolation scheme. Isolated yeasts, both from dye-polluted and virgin environments, were compared for their textile dye decolourization ability when cultured on solid and liquid media. Nine isolates from wastewater and 17 from Las Yungas showed the highest decolourization potential on agar plates containing six different reactive dyes, either alone or as a mixture. Five yeasts from each environment were further selected on the basis of their high dye removal rate in Vilmafix Red 7B-HE- or Vilmafix Blue RR-BBamended liquid cultures. Yeasts from wastewater showed slightly higher decolourization percentages after 36 h of culture than yeasts from Las Yungas (98?100% vs. 91?95%, respectively). However, isolates from Las Yungas exhibited higher specific decolourization rates than isolates from effluents (1.8?3.0 vs. 0.9?1.3 mg g-1 h-1 , respectively). All selected isolates were first grouped according to microsatellite-PCR analysis and representative isolates from each group were subsequently identified based on the 26S rRNA gene sequence analysis. Yeasts from wastewater were identified as the ascomycetous Pichia kudriavzevii (100%) and closely related to Candida sorbophila (99.8%), whilst yeasts from Las Yungas were identified as the basidiomycetous Trichosporon akiyoshidainum and Trichosporon multisporum. It is suggested that findings concerning yeast selection during screening programs for dye-decolourizing yeasts may be explained in the light of the copiotroph-oligotroph microorganisms rationale. Fil: Pajot, Hipólito Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina Fil: Delgado, Osvaldo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina Fil: Castellanos de Figueroa, Lucia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina Fil: Fariña, Julia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Planta Piloto de Procesos Industriales Microbiológicos (i); Argentina

Sediments of fluvial streams are a sink for pollutants such as heavy metals and organic recalcitrant compounds. In anoxic conditions, sulphide generation and alkalinisation cause precipitation of heavy metals. The redox potential of the system could change to higher values, mainly owing to oxygen exposition generated by anthropogenic disturbances of the sediment such as dredging operations. Knowledge about the mechanisms involved is fundamental to assess the risk of acid generation and rise in heavy metals bioavailability. In this paper, the characterisation and assessment of acidification risk of sediments of a contaminated stream near Buenos Aires was carried out by static and kinetic assays. Speciation of heavy metals was determined after metal sequential extraction procedure. Also, re-suspension of sediments assay in batch mode, with and without Acidithiobacillus ferrooxidans inoculum, was carried out to assess the chemical changes that occur at oxygen exposure, verifying the acidification and heavy metal release processes. Fil: Porzionato, Natalia Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina Fil: Candal, Roberto Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina Fil: Curutchet, Gustavo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina