Toxicity of phenol solutions treated with rapeseed and tomato hairy roots

Phenolic compounds are frequently found in several industrial effluents. Recently, the use of hairy root cultures has been explored as a new alternative for their treatment. In this study, rapeseed and tomato hairy roots (HR) were used to remove phenol efficiently (100 to 250 mg/L) from aqueous solutions in a short time. The removal efficiencies were 95-80% and 60-70% for rapeseed and tomato HR respectively. Polyethyleneglycol (PEG-3350) addition to the reaction medium, significantly enhanced removal efficiency of rapeseed HR reaching values of 98-88%. After the removal process the acute toxicity of post-removal solutions was determined by means of AMPHITOX bioassay. Phenol solutions treated with rapeseed HR showed a lower level of toxicity than at the beginning of the treatment. Moreover, PEG addition reduced the toxicity of these solutions. On the contrary, tomato HR could only be applied to reduce the level of toxicity in solutions initially containing low phenol concentrations (100-150 mg/L), without adding PEG. From these results, it is relevant to point out the importance of studying different plant systems and their reaction capacity to find the more suitable ones for removal purposes.Fil: Paisio, Cintia Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: González, Paola Solange. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gerbaudo, Alejandra. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; ArgentinaFil: Betuzzi, Mabel Lucia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Characterization of a phenol-degrading bacterium isolated from an industrial effluent and its potential application for bioremediation

The use of native microorganisms is a useful strategy for phenol bioremediation. In the present work, a bacterial strain, named RTE1.4, was isolated from effluents of a chemical industry. The strain was able to grow at high concentrations of phenol and its derivatives, such as guaiacol, 2,4-dichlorophenol and pentachlorophenol, as well as in a medium containing industrial effluents. This bacterium was identified as Acinetobacter sp. using morphological, physiological, biochemical and 16S rRNA gene analysis. Acinetobacter sp. RTE1.4 degraded phenol (200 to 600 mg/L) at wide pH range and temperature (5-9 and 25-37°C, respectively) demonstrating high adaptation ability to different conditions. The strain would metabolize phenol by the ortho-pathway since catechol 1,2-dioxygenase activity was detected. When bacteria were grown in medium containing phenol, an altered whole-cell protein pattern was observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), with the lack of some low-molecular mass polypeptides and an increase in the relative abundance of high-molecular mass proteins after treatment. Considering that the use of native strains in bioremediation studies shows several ecological advantages and that the studied bacterium showed high tolerance and biodegradation capabilities, Acinetobacter sp. RTE1.4 could be an appropriate microorganism for improving bioremediation and biotreatment of areas polluted with phenol and/or some of its derivatives. Moreover, the establishment of the optimal growth conditions (pH, temperature, concentration of the pollutant) would provide baseline data for bulk production of the strain and its use in bioremediation processes. © 2013 Copyright Taylor and Francis Group, LLC.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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: González, Paola Solange. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; ArgentinaFil: Pajuelo Domínguez, Eloisa. Universidad de Sevilla; EspañaFil: 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Evaluation of phenol detoxification by Brassica napus hairy roots, using Allium cepa test

Introduction: Meristematic mitotic cells of Allium cepa constitute an adequate material for cytotoxicity and genotoxicity evaluation of environmental pollutants, such as phenol, which is a contaminant frequently found in several industrial effluents. Results and discussion: In the present work, Brassica napus hairy roots (HR) were used for phenol removal assays. The toxicity of post-removal solutions (PRS) and phenol solutions was analyzed. These HR removed the contaminant with high efficiency (100-80% for phenol solutions containing 10-250 mg/L, respectively). Phenol solutions treated with B. napus HR showed a significant reduction of general toxicity compared to untreated phenol solutions, since the IC50 values were 318. 39 and 229. 02 mg/L, respectively. Moreover, PRS presented lower cytotoxicity and genotoxicity than that found in phenol solutions untreated. The mitotic index (MI) observed in meristematic cells treated with PRS (100 and 250 mg/L of phenol) showed an increase of 35% and 42%, whereas the chromosome aberrations showed a significant decrease. According to these results, B. napus HR cultures could be used for the treatment of solutions contaminated with phenol, since we observed not only high removal efficiency, but also an important reduction of the general toxicity, cytotoxicity, and genotoxicity.Fil: González, Paola Solange. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Maglione, Guillermo A.. Universidad Nacional de Río Cuarto; ArgentinaFil: Giordana, Micaela. Universidad Nacional de Río Cuarto; ArgentinaFil: Paisio, Cintia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

Characterization of effluents from a tannery industry: A case study of Córdoba province, Argentina

Tannery effluents are considered to be severe pollutants around the world. The characterization of such effluents is a very important task in order to verify the compliance with legal requirements of the discharge and, if necessary, to optimize their treatment. In this study, we used the effluents from a local tannery (Córdoba, Argentina) that had implemented only a primary treatment. The effluents were periodically collected during one year to assess their physical, chemical, and microbiological characteristics, as well as their toxicity. The physical and chemical characteristics showed variations independently of the sampling time, although, in general, a high nutrient load was the most frequent finding. Moreover, parameters such as chemical oxygen demand, biochemical oxygen demand, total nitrogen, total phosphate, total phenols, Cr(VI) and settleable solids exceeded the limit set by the provincial legislation for the discharge of effluents into surface water bodies. The effluents were also characterized by a high count of bacteria, where pollutant-tolerant and some pathogenic bacteria were found. In sampling 9, Bacteroidetes, Firmicutes and Proteobacteria represented up to 93 % of the total number of sequences obtained, with Paludibacter, Tissierella Soehngenia, Proteocatella and Proteiniclasticum as the most abundant genera. In concordance with these results, all samples showed toxicity according to L. sativa and AMPHITOX bioas-says. Altogether, data from this report indicate the need to optimize primary treatment of the effluents, as well as to include complementary treatments in order to reduce the negative environmental impacts of the release of this kind of runoffs.Los efluentes de las curtidurías se consideran contaminantes graves en todo el mundo. La caracterización de dichos efluentes es una tarea muy importante para verificar el cumplimiento de los requisitos legales de vertido y, en caso de ser necesario, optimizar el tratamiento de efluentes. En este estudio utilizamos los efluentes de una curtiduría local (Córdoba, Argentina) que había implementado sólo un tratamiento primario. Los efluentes fueron recolectados periódicamente durante un año para evaluar sus caracte- rísticas físicas, químicas y microbiológicas, así como su toxicidad. Las características físicas y químicas mostraron variaciones independientemente del tiempo de muestreo, aunque, en general, el hallazgo más frecuente fue una alta carga de nutrientes. Además, parámetros como demanda química de oxígeno, demanda bioquímica de oxígeno, ni- trógeno total, fosfato total, fenoles totales, Cr(VI) y sólidos sedimentables, superaron los límites establecidos por la legislación provincial para el vertido de efluentes en aguas superficiales. Los efluentes también se caracterizaron por un alto recuento de bacterias, encontrándose bacterias tolerantes a contaminantes y algunos patógenos. En la muestra 9, Bacteroidetes, Firmicutes y Proteobacteria representaron en conjunto hasta el 93 % del número total de secuencias obtenidas, siendo Paludibacter, Tissierella Soehngenia, Proteocatella y Proteiniclasticum los géneros más abundantes. De acuerdo con estos resultados, todas las muestras presentaron toxicidad según los bioensayos de L. sativa y AMPHITOX. En conjunto, los datos de este informe indican la necesidad de optimizar el tratamiento primario de los efluentes, así como de incluir tratamientos complementarios para reducir los impactos ambientales negativos de la liberación de este tipo de efluentes.Fil: Fernandez, Marilina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: González, Paola Solange. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; ArgentinaFil: Boarini, Milena Belen. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; ArgentinaFil: Mandille, Josefina. Universidad Nacional de Río Cuarto; ArgentinaFil: Barberón, Ignacio. Universidad Nacional de Río Cuarto; ArgentinaFil: Perotti, Romina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Pereira, Paola Patricia. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Application of two bioassays as potential indicators of phenol phytoremediation efficiency by tobacco hairy roots

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; ArgentinaFil: 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; ArgentinaFil: 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; Argentin

Selection and optimization of a mixed culture for bioaugmentation based on BOD5 and COD reduction in tannery effluents

Most current methodologies for the treatment of tannery effluents do not succeed in bringing contaminant levels down to values that fit environmental standards in force, which means there is a need for appropriate optimization. The present work assessed effluent quality to gain further insight into their variability across time, considering both conventional parameters and those specifically related to tannery effluents, such as chromium levels. Most of the effluents analyzed exceeded the contaminant limits established by current national legislation and therefore would require treatment. To improve treatment efficiency, a mixed bacterial culture was selected on the basis of its ability to remove organic matter (OM), measured in terms of chemical oxygen demand (COD) and biochemical oxygen demand (BOD5). The four strains analyzed, belonging to the genera Bacillus, Rhodococcus and Acinetobacter, were isolated from sediments contaminated with effluents with a high organic load. The native consortium SFC 500-1, formed by Acinetobacter guillouiae SFC 500-1 A and Bacillus toyonensis SFC 500-1E, proved to be the most effective at reducing BOD5 and COD. It was selected for bioaugmentation treatment. Dissolved oxygen was found to be key for reduction, and the inoculum size required to treat effluents with different COD values was also determined. All in all, the results confirmed previous characterization of these effluents, which should always be the basis for treatment and management strategies, and also contributed to optimizing some operational parameters so that effective and safe treatment technologies may be developed.Fil: Perotti, Romina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: González, Paola Solange. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Paisio, Cintia Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Remediación biológica de mercurio: Recientes avances

Mercury (Hg) is a highly toxic heavy metal that threatens human health and environment. It is found naturally as inorganic and organic forms and all are toxic, especially the latter, due to its high lipid solubility, which facilitates their biomagnification in the food chain. Due to the high risks that represent the Hg-contaminated environments, there is a need to efficiently treat them. Among environmental restoration strategies, the biological remediation is a promising technology, which comprises the bio-, phyco-, phyto- and rhizoremediation. Thus, the purpose of this review was to compilate the main aspects concerning to biological remediation of Hg, emphasizing the most recent developments, in order to contribute to the understanding of the mechanisms involved in it and the aspects that still need to be investigated. Thereby, in this review we describe the different mechanisms implicated and the capacity for Hg and methylmercury removal by bacteria, fungi, algae, plants and rhizospheric microorganisms. In addition, it describes the results using transgenic plants, which have been obtained to improve the removal process of this metal. For decades, numerous investigation involving bacterial bioremediation and phytoremediation of Hg have been developed. However, the use of fungi and algae for this purpose are less explored areas. More recently, new areas into the Hg-biological remediation are being studied, such as the rhizoremediation and the use of transgenic plants, which need to be further studied in order to elucidate its biotechnological potential. The application of these systems to treat industrial effluents and/or environments contaminated with Hg is also discussed.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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: González, Paola Solange. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Biología Molecular. Sección Química Biológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: 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 - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Phytoremediation processes of domestic and textile effluents: evaluation of the efficacy and toxicological effects in Lemna minor and Daphnia magna

Phytoremediation has been proposed as a potential biotechnological strategy to remediate effluents before their release into the environment. The use of common aquatic plant species, such as macrophytes (e.g., Lemna spp.) as a cleanup solution has been proposed decades ago. However, the effectiveness of such processes must be assessed by analyzing the toxicity of resulting effluents, for the monitoring of wastewater quality. To attain this purpose, this work intended to quantify the efficacy of a Lemna-based wastewater phytoremediation process, by analyzing toxicological effects of domestic and textile effluents. The toxic effects were measured in Lemna minor (same organisms used in the phytoremediation process, by quantifying toxicological endpoints such as root length, pigment content, and catalase activity) and by quantifying individual parameters of Daphnia magna (immobilization, reproduction, and behavior analysis). Phytoremediation process resulted in a decrease of chemical oxygen demand in both effluents and in an increase in root length of exposed plants. Moreover, textile effluent decreased pigments content and increased catalase activity, while domestic effluent increased the anthocyanin content of exposed plants. D. magna acute tests allowed calculating a EC50 and Toxic Units interval of 53.82–66.89%/1.85–1.49, respectively, to raw textile effluent; however, it was not possible to calculate these parameters for raw and treated domestic effluent (RDE and TDE). Therefore, in general, the acute toxicity of effluent toward D. magna was null for RDE, and mild for the treated textile effluent (TTE), probably due to the effect of phytoremediation. Exposure to textile effluents (raw and treated) increased the total number of neonates of D. magna and, in general, both textile effluents decreased D. magna distance swim. Moreover, although both effluents were capable of causing morphological and physiological/biochemical alterations in L. minor plants, organisms of this species were able to survive in the presence of both effluents and to remediate them.Fil: Alkimin, Gilberto Dias de. Universidade de Aveiro. Centro de Estudos do Ambiente e do Mar; PortugalFil: 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; ArgentinaFil: 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; ArgentinaFil: Nunes, Bruno. Universidade de Aveiro. Centro de Estudos do Ambiente e do Mar; Portugal. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentin

Sequential application of activated sludge and phytoremediation with aquatic macrophytes on tannery effluents: in search of a complete treatment

Tannery effluents with a high organic matter load (indicated by their COD level) have to be treated before they are discharged, so as to minimize their negative impact on the environment. Using field mesocosm systems, this study evaluated the feasibility of treating such effluents through bioaugmentation with activated sludge, followed by phytoremediation with aquatic macrophytes (Lemnoideae subfamily). Regardless of its quality, the activated sludge was able to remove approximately 77% of the COD from effluents with a low initial organic load (up to 1500 mg/L). The macrophytes then enhanced removal (up to 86%), so the final COD values were permissible under the current legislation for effluent discharge. When the initial organic load in the undiluted effluents was higher (around 3000 mg/L), the COD values obtained after consecutive bioaugmentation and phytoremediation were close to the legally allowed limits (583 mg/L), which highlights the potential of phytoremediation as a tertiary treatment. This treatment also brought total coliform counts down to legally acceptable values, without plant biomass decreasing over time. Moreover, the plant biomass remained viable and capable of high COD removal efficiency (around 75%) throughout two additional reuse cycles. These findings indicate that the efficiency of the biological treatments assayed here depends largely on the initial organic load in the tannery effluents. In any case, the sequential application of activated sludge and aquatic macrophytes proved to be a successful alternative for remediation.Fil: Fernandez, Marilina. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; ArgentinaFil: Gómez, Roxana J.. Universidad Nacional de Río Cuarto; ArgentinaFil: González, Paola Solange. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; ArgentinaFil: Barroso, Cintia Natalí. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; ArgentinaFil: Paisio, Cintia Elizabeth. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Biotecnologia Ambiental y Salud. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Biotecnologia Ambiental y Salud.; Argentin

Synergistic effect of chickpea plants and Mesorhizobium as a natural system for chromium phytoremediation

The presence of chromium in soils not only affects the physiological processes of plants but also the microbial rhizosphere composition and metabolic activities of microorganisms. Hence, the inoculation of plants with Cr(VI)-tolerant rhizospheric microorganisms as an alternative to reduce Cr phytotoxicity was studied. In this work, chickpea germination was reduced by Cr(VI) concentrations of 150 and 250 mg/L (6 and 33%, respectively); however lower Cr(VI) concentrations negatively affected the biomass. On the other hand, its symbiont, Mesorhizobium ciceri, was able to grow and remove different Cr(VI) concentrations (5–20 mg/L). The inoculation of chickpea plants with this strain exposed to Cr(VI) showed a significantly enhanced plant growth. In addition, inoculated plants accumulated higher Cr concentration in roots than those noninoculated. It is important to note that Cr was not translocated to shoots independently of inoculation. These results suggest that Mesorhizobium’s capability to remove Cr(VI) could be exploited for bioremediation. Moreover, chickpea plants would represent a natural system for phytoremediation or phytostabilization of Cr in situ that could be improved with M. ciceri inoculation. This strategy would be considered as a phytoremediation tool with great economic and ecological relevance.Fil: Velez, Pilar Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Paisio, Cintia Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: González, Paola Solange. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin