The inhibition effect of limonene on the organisms involved in anaerobic reactors may affect obtaining H2 in this process. Rapid and precise limonene quantification is desirable to characterize wastewaters. The objective of this research was to develop a Gas Chromatography Coupled to Mass Spectrometry (GC-MS) method to determine limonene concentration in liquid samples from batch reactors applied to H2 production at 30 ºC. Method validation was carried out through calibration curves (3 to 20 mg L-1of limonene), in addition to evaluating its precision (CV =0.1%), linearity (R2=0.979), limits of detection (1.7 mg L-1) and quantification (4.2 mg L-1). Its inhibitory effect was evaluated with increasing concentrations of limonene (without addition to 2000 mg L-1). Limonene affected the starting time of H2 production (λ), since λ was 8.7 h in control assays and 15 h with 2000 mg L-1 of limonene. The same was observed for obtaining H2, since 19.5 mmol H2 L-1 was obtained in control assays and 8.7 mmol H2 L-1 was obtained in assays with 2000 mg L-1 of limonene. This method was effective for limonene determination in liquid samples from batch reactors and could be used for characterization and control of anaerobic reactors.

RESUMO Biossurfactantes são moléculas multifuncionais produzidas por microrganismos e podem apresentar vantagens em relação aos surfactantes sintéticos, como baixa toxicidade, alta biodegradabilidade, maior redução da tensão superficial e alta diversidade química. No entanto, a produção em escala comercial ainda é escassa devido ao elevado custo dos substratos utilizados. Portanto, no presente trabalho foi avaliada a produção de biossurfactantes utilizando diferentes óleos como fonte de carbono, como óleo de soja, óleo de fritura, óleo diesel, óleo lubrificante novo e usado, a partir de dois gêneros de bactérias isoladas de lodo indústria de cosméticos e solo contaminado com óleo diesel, Lysinibacillus sp. e Bacillus sp. respectivamente. Estas foram identificadas por sequenciamento do fragmento do gene RNAr 16S e mantidas sob refrigeração a 4 ºC em tubos de ensaio, com ágar triptona de soja. Os ensaios de produção foram realizados sob agitação de 200 rpm a 30 °C com duração de 7 dias. A produção de biossurfactante foi analisada pela atividade emulsificante, índice emulsificação e por colapso da gota. As bactérias utilizadas produziram biossurfactante em todos os tipos de óleos testados. O óleo de soja mostrou-se o melhor substrato para produção de biossurfactante a partir do Lysinibacillus sp. e Bacillus sp. com índice de emulsificação de 50 % e 46,63 %, respectivamente.

ABSTRACT Biosurfactants are multifunctional molecules produced by microorganisms and havea some advantages compared to synthetic surfactants, such as low toxicity, high biodegradability ,improved tensoactivity and chemical diversity. However, commercial scale production is not viable due to the high cost of the substrates used. Therefore, in the present work we evaluated the production of biosurfactants using different oils as carbon source, such as soybean oil, frying oil, diesel oil, new and used lubricating oil, from two genera of bacteria isolated from sludge cosmetics industry and soil contaminated with diesel oil, Lysinibacillus sp. and Bacillus sp. respectively. These were identified by sequencing the 16S rRNA gene fragment and kept under refrigeration at 4 ° C in test tubes with tryptone soy agar. The production was carried out under agitation at 200 rpm at 30 °C for 7 days. The biosurfactant production was analyzed by emulsifying activity, emulsification index and drop collapse. The bacteria used produced biosurfactant in all types of oils tested. Soybean oil was the best substrate for the production of biosurfactant from Lysinibacillus sp. and Bacillus sp. with an emulsification index of 50% and 46.63%, respectively.

RESUMO Avaliou-se neste trabalho os fatores de risco associados com a ocorrência de coliformes totais (CT), coliformes fecais (CF) e ovos de parasitas intestinais (OPI) em hortaliças que chegavam a uma agroindústria do município de Ibiúna- SP. Foi aplicado um questionário com 17 questões para 24 produtores a fim de realizar o diagnóstico dos fatores de risco e a sua posterior associação com a presença ou não de CT, CF e OPI. As questões versavam principalmente sobre o sistema de produção, adubo empregado, origem da água utilizada para irrigação, higienização das hortaliças e forma de transporte. Para a pesquisa de CT, CF e OPI, as amostras foram processadas no laboratório de microbiologia e parasitologia do Instituto Federal de São Paulo, campus São Roque. Os resultados revelaram que em 100% das amostras investigadas foram encontrados CT, e em 95,83%, detectados CF. Houve associação estatística significante para o fator de risco utilização de água de açude onde havia lançamento de águas residuais e ausência de higienização de hortaliça no ato da colheita em relação a presença de CF. Ovos de parasitas intestinais foram encontrados em 33,33% das amostras.

ABSTRACT In this study, we evaluated the risk factors associated with the occurrence of total coliforms, thermotolerant coliforms, and intestinal parasite eggs in vegetables from an agroindustry in the city of Ibiúna - SP, Brazil. A questionnaire with 17 questions was applied to 24 producers to carry out a diagnosis of the risk factors and their posterior association or not with total coliforms, thermotolerant coliforms, and intestinal parasite eggs. The questions addressed mainly the production system, fertilizer used, source of the water used for irrigation, sanitization of the vegetables, and form of transport. For the investigation of total coliforms, thermotolerant coliforms, and intestinal parasite eggs, the samples were processed at the microbiology and parasitology laboratory of the Federal Institute of São Paulo, São Roque Campus. The results revealed that total coliforms were found in 100% of the investigated samples and thermotolerant coliforms were detected in 95.83% of the samples. There was a significant statistical association for the risk factor use of reservoir water, where there was release of wastewater and absence of sanitization of the vegetables at the moment of harvest in relation to the presence of thermotolerant coliforms. Intestinal parasite eggs were found in 33.33% of the samples.

Resumo: Objetivo As comunidades microbianas desempenham papel crucial nos processos ambientais como na mineralização de matéria orgânica e ciclagem de nutrientes em ambientes aquáticos. No entanto, apesar da importância ecológica de archaea e bactéria em ambientes aquáticos, a estrutura destas comunidades permanece pouco estudada. Métodos Neste sentido, nos avaliamos a riqueza e densidade de archaea e bactéria na coluna d’água e no sedimento do reservatório de Itupararanga e avaliamos as relações entre os fatores bióticos e abióticos. Para tanto, amostragens foram realizadas em cinco profundidades na região próxima a barragem e em três profundidades no ponto da entrada. Resultados A partir de PCR-DGGE observou-se que ambas as comunidades distribuíram-se ao logo dos pontos de amostragem, mesmo em condições com presença de oxigênio. Conclusões A densidade bacterianas, avaliada por qPCR foi maior do que a de archaea, provavelmente devido a maior plasticidade metabólica desses microrganismos.

Abstract Aim: Microbial communities play a central role in environmental process such as organic matter mineralization and the nutrient cycling process in aquatic ecosystems. Despite their ecological importance, variability of the structure of archaeal and bacterial communities in freshwater remains understudied. Methods In the present study we investigated the richness and density of archaea and bacteria in the water column and sediments of the Itupararanga Reservoir. We also evaluated the relationship between the communities and the biotic and abiotic characteristics. Samples were taken at five depths in the water column next to the dam and three depths next to the reservoir entrance. Results PCR-DGGE evaluation of the archaeal and bacterial communities showed that both were present in the water column, even in oxygenated conditions. Conclusions The density of the bacteria (qPCR) was greater than that of the archaea, a result of the higher metabolic plasticity of bacteria compared with archaea.

The objective of this study was to evaluate the degradation of Linear Alkylbenzene Sulfonate (LAS) in anaerobic sequencing batch reactor (ASBR) under denitrifying conditions using swine sludge as inoculum. The reactor was operated for 104 days with synthetic substrate containing nitrate, and LAS was added later (22 mg/L). Considering the added mass of the LAS, the adsorbed mass in the sludge and discarded along with the effluent, degradation of the surfactant at the end of operation was 87%, removal of chemical oxygen demand was 86% and nitrate was 98%. The bacterial community was evaluated by cutting the bands and sequencing of polymerase chain reaction (PCR) fragments and denaturing gradient gel electrophoresis (DGGE). The sequences obtained were related to the phylum Proteobacteria and the alpha-and beta-proteobacteria classes, these bacteria were probably involved in the degradation of LAS. The efficiently degraded LAS in the reactor was operated in batch sequences in denitrifying conditions.

El alquilbenceno sulfonato lineal (LAS) es el tensoactivo sintético más usado en todo el mundo en los produtos de limpeza domestica e industrial y puede llegar a las masas de agua a través de la descarga de aguas residuales sin tratamiento o con un tratamiento ineficaz. El objetivo del estudio consistió en evaluar la capacidad de la microbiota presente en el sedimento del río Tietê en la degradación del tensoactivo anionico - LAS. El experimento se llevó a cabo en un bioreactor de lotes secuenciales en condiciones de desnitrificación con ciclos de 24 horas, agitación de 150rpm, usando 430mL de sedimento y 1 070mL de sustrato sintético constituido por extracto de levadura, almidón soluble, bicarbonato de sodio y sacarosa. El LAS fue añadido a diferentes concentraciones de 15mg/L y 30mg/L. El funcionamiento del bioreactor se dividió en la adaptación de la biomasa con sustrato sintético sin LAS y tres condiciones experimentales: A) adición de 15mg/L de LAS; B) 15mg/L de LAS y reducción del 50% de la concentración del co-sustrato y C) 30mg/L de LAS y la concentración de 100% de co-substrato. Los resultados obtenidos muestran que la eficiencia en la degradación del LAS está directamente relacionada con la población de bacterias desnitrificadoras y que el sedimento del río Tietê se puede utilizar como inóculo en el tratamiento de LAS en condiciones desnitrificadoras. La población de bacterias fue capaz de degradar el LAS independiente de la fuente de carbón adicionada. La remoción de LAS y de nitrato se puede lograr simultáneamente en aguas residuales con una baja carga orgánica. La reducción de la concentración del co-sustrato fue influenciado directamente por la población de bacterias desnitrificantes (2.2x10(13) a 1.0x10(8)MNP/gTVS) y por lo tanto la degradación de LAS (60.1-55.4%). Los microorganismos en el sedimento del río Tietê se pueden usar como inóculo alternativo para el tratamiento de efluentes contaminados con nitrato y LAS.

Linear alkylbenzene sulfonate (LAS) is widely used in the formulation of domestic and industrial cleaning products, the most synthetic surfactants used worldwide. These products can reach water bodies through the discharge of untreated sewage or non-effective treatments. This study evaluates the ability of the microorganisms found in the Tietê river sediment to degrade this synthetic surfactant. The experiment was conducted in a bioreactor, operated in batch sequences under denitrifying conditions, with cycles of 24 hours and stirring at 150rpm, using 430mL of sediments and 1 070mL of a synthetic substrate consisting of yeast extract, soluble starch, sodium bicarbonate and sucrose. LAS was added at different concentrations of 15mg/L and 30mg/L. The reactor operation was divided into the biomass adaptation to the synthetic substrate without LAS and three experimental conditions: a) addition of 15mg/L of LAS; b) 50% reduction the co-substrate concentration and 15mg/L of LAS, and c) addition of 30mg/L of LAS and 100% co-substrate concentration. The results showed that the degradation efficiency of LAS was directly related to the addition of co-substrates and the population of denitrifying bacteria. The removal of LAS and nitrate can be achieved simultaneously in wastewater with low organic loads. The reduction in the co-substrates concentration was directly influenced by the number of denitrifying bacteria (2.2x10(13) to 1.0x10(8)MPN/gTVS), and consequently, LAS degradation (60.1 to 55.4%). The sediment microorganisms in the Tietê river can be used as an alternative inoculum in the treatment of wastewater with nitrate and LAS contamination.

In this work, the biological denitrification associated with anoxic oxidation of methane and the microbial diversity involved were studied. Kinetic tests for nitrate (NO3-) and nitrite (NO2-) removal and methane uptake were carried out in 100 mL batch reactors incubated in a shaker (40 rpm) at 30 ºC. Denitrificant/methanotrophic biomass was taken from a laboratory scale reactor fed with synthetic nitrified substrates (40 mgN L-1 of NO3- and subsequently NO2-) and methane as carbon source. Results obtained from nitrate removal followed a first order reaction, presenting a kinetic apparent constant (kNO3)) of 0.0577±0.0057d-1. Two notable points of the denitrification rate (0.12gNO3--N g-1 AVS d-1 and 0.07gNO3--N g-1 AVS d-1) were observed in the beginning and on the seventh day of operation. When nitrite was added as an electron acceptor, denitrification rates were improved, presenting an apparent kinetic constant (kNO2) of 0.0722±0.0044d-1, a maximum denitrification rate of 0.6gNO2--N g-1AVS d-1, and minimum denitrification rate of 0.1gNO2--N g-1AVS d-1 at the beginning and end of the test, respectively. Endogenous material supporting denitrification and methane concentration dissolved in the substrate was discarded from the control experiments in the absence of methane and seed, respectively. Methylomonas sp. was identified in the reactors fed with nitrate and nitrite as well as uncultured bacterium.

Um reator de escoamento contínuo, inoculado com Aspergillus niger AN400, possuía volume total de 5 L e foi operado a 29ºC, com oito horas de tempo de detenção hidráulica e 150 L.h-1 de vazão de ar, para remover 25 mg.L-1 de corante vermelho do congo de água residuária sintética. A alimentação do reator foi realizada em duas fases: Fase I, com 0,5 g.L-1 de sacarose e Fase II, sem sacarose. Na Fase I, foi possível observar eficiências de remoção de matéria orgânica (mg de DQO.L-1) e de cor (mg PT.L-1) de 80 ± 16% e 82 ± 10% (mg Pt.L-1), respectivamente. Na Fase II, a eficiência de remoção de matéria orgânica foi de 75 ± 13% e de cor (mg Pt.L-1) de 89 ± 7%. As maiores remoções de nutrientes foram alcançadas pelo reator na Fase I, com 25% de amônia, 90% de nitrito, 93% de nitrato e 21% de fósforo. Aparentemente, a presença de sacarose melhorou a remoção dos nutrientes.

A continuous flow reactor, inoculated with Aspergillus niger AN400, with total volume of 5 L was operated at 29oC, with eight hours of retention hydraulic time and 150 L.h-1 of air flow rate in order to remove 25 mg.L-1 of Congo Red dye from a synthetic wastewater. The feeding of the reactor, inoculated with Aspergillus niger AN400, was done in two phases: Phase I, with 0,5 g/L of saccharose and Phase II, with no saccharose. In Phase I, it was possible to verify efficiencies of organic matter and color (mg Pt.L-1) removal of 80 ± 16% and 82 ± 10%, respectively. In Phase II, the efficiency of organic matter removal was 75 ± 13% and color removal was 89 ± 7%. The higher removals of nutrients were achieved by the reactor in Phase I with 25% to ammonia, 90% to nitrite, 93% to nitrate and 21% to phosphorus. Apparently, the presence of saccharose improved the removal of the nutrients.