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BACKGROUND: The production of agricultural wastes still growing as a consequence of the population growing. However, the majority of these residues are under-utilized due their chemical composition, which is mainly composed by cellulose. Actually, the search of cellulases with high efficiency to degrade this carbohydrate remains as the challenge. In the present experiment, two genes encoding an endoglucanase (EC 3.2.1.4) and ß-glucosidase (EC 3.2.1.21) were overexpressed in Escherichia coli and their recombinant enzymes (egl-FZYE and cel-FZYE, respectively) characterized. Those genes were found in Trabulsiella odontermitis which was isolated from the gut of termite Heterotermes sp. Additionally, the capability to release sugars from agricultural wastes was evaluated in both enzymes, alone and in combination. RESULTS: The results have shown that optimal pH was 6.0 and 6.5, reaching an activity of 1051.65 ± 47.78 and 607.80 ± 10.19 U/mg at 39 °C, for egl-FZYE and cel-FZYE, respectively. The Km and Vmax for egl-FZYE using CMC as substrate were 11.25 mg/mL and 3921.57 U/mg, respectively, whereas using Avicel were 15.39 mg/mL and 2314.81 U/mg, respectively. The Km and Vmax for cel-FZYE using Avicel as substrate were 11.49 mg/mL and 2105.26 U/mg, respectively, whereas using CMC the enzyme did not had activity. Both enzymes had effect on agricultural wastes, and their effect was improved when they were combined reaching an activity of 955.1 ± 116.1, 4016.8 ± 332 and 1124.2 ± 241 U/mg on corn stover, sorghum stover and pine sawdust, respectively. CONCLUSIONS: Both enzymes were capable of degrading agricultural wastes, and their effectiveness was improved up to 60% of glucose released when combined. In summary, the results of the study demonstrate that the recombinant enzymes exhibit characteristics that indicate their value as potential feed additives and that the enzymes could be used to enhance the degradation of cellulose in the poor-quality forage generally used in ruminant feedstuffs.

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Thousands of people living in semi-arid regions face problems of drought and loss of water quality. In addition, high incidence of acute diarrheal diseases related to water consumption has been responsible for a high number of deaths and high economic costs for human health. Many of the diseases can be caused by the presence of enterobacteria in reservoirs that serve for multiple purposes. This study aimed to confirm the presence of potentially harmful bacteria, which was highlighted in other articles, and to reveal non-identified genera by culture-dependent methods and pyrosequencing. Twenty-three genera of the Enterobacteriaceae family were detected, with emphasis on Escherichia genus and confirmation of the presence of species such as Salmonella enterica and Enterobacter cloacae. The abundance of heterotrophic prokaryotes and the physical and chemical data show an expected average for this type of environment due to the numbers historically presented in previous articles. The unprecedented detection of the presence of some potentially pathogenic species can alert and raise awareness of the populations that use stored water in the semi-arid regions. Consequently, as a result of the peculiar characteristics of reservoirs under this climate influence, there is a cosmopolitanism of enterobacteria that may be related to the alarming numbers of infections from Waterborne Diseases.

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Thousands of people living in semi-arid regions face problems of drought and loss of water quality. In addition, high incidence of acute diarrheal diseases related to water consumption has been responsible for a high number of deaths and high economic costs for human health. Many of the diseases can be caused by the presence of enterobacteria in reservoirs that serve for multiple purposes. This study aimed to confirm the presence of potentially harmful bacteria, which was highlighted in other articles, and to reveal non-identified genera by culture-dependent methods and pyrosequencing. Twenty-three genera of the Enterobacteriaceae family were detected, with emphasis on Escherichia genus and confirmation of the presence of species such as Salmonella enterica and Enterobacter cloacae. The abundance of heterotrophic prokaryotes and the physical and chemical data show an expected average for this type of environment due to the numbers historically presented in previous articles. The unprecedented detection of the presence of some potentially pathogenic species can alert and raise awareness of the populations that use stored water in the semi-arid regions. Consequently, as a result of the peculiar characteristics of reservoirs under this climate influence, there is a cosmopolitanism of enterobacteria that may be related to the alarming numbers of infections from Waterborne Diseases.(AU)

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Enterobacteriaceae can be present in the environment and in the intestine of warmblooded animals. This study aimed to isolate and identify enterobacteria in informally marketed milk in cities of South of the Piaui. 52 milk samples were acquired at different points of Bom Jesus, Redenção do Gurguéia, Santa Luz and Cristino Castro, Piaui, which were taken into Styrofoam containing ice to food microbiology laboratory of the Federal University of Piauí, in Bom Jesus, where held the bacterial isolation in MacConkey, EMB and XLD. The conclusive biochemical identification and agglutination test was held at the Enterobacteria Laboratory of FIOCRUZ, (Rio de Janeiro-RJ). From the 37 strains, identified the species Escherichia coli, Enterobacter cloacae, Enterobacter gergoviae, Enterobacter aerogenes, Klebsiella pneumoniae, Citrobater freundii, Providencia rettigeri and Serratia marcescens. The informally marketed milk is contaminated by Enterobacteriaceae that can be pathogenic and should be taken preventive measures, such as pasteurization of milk.(AU)

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Enterobacteriaceae can be present in the environment and in the intestine of warmblooded animals. This study aimed to isolate and identify enterobacteria in informally marketed milk in cities of South of the Piaui. 52 milk samples were acquired at different points of Bom Jesus, Redenção do Gurguéia, Santa Luz and Cristino Castro, Piaui, which were taken into Styrofoam containing ice to food microbiology laboratory of the Federal University of Piauí, in Bom Jesus, where held the bacterial isolation in MacConkey, EMB and XLD. The conclusive biochemical identification and agglutination test was held at the Enterobacteria Laboratory of FIOCRUZ, (Rio de Janeiro-RJ). From the 37 strains, identified the species Escherichia coli, Enterobacter cloacae, Enterobacter gergoviae, Enterobacter aerogenes, Klebsiella pneumoniae, Citrobater freundii, Providencia rettigeri and Serratia marcescens. The informally marketed milk is contaminated by Enterobacteriaceae that can be pathogenic and should be taken preventive measures, such as pasteurization of milk.

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The Suquía River lower-middle basin (Córdoba, Argentina) is subject to a strong anthropic impact because it receives pollutants from different sources (industries, wastewaters, heavy traffic, agricultural land use, etc.) We have assessed the degree of watershed degradation of Suquía River lower-middle sections through the analysis of different ecosystem compartments (air, water, riparian soil, sediments and biota), in order to provide useful data to be considered in future river restoration programs. Four study sites were selected along the river (La Calera city, Córdoba city, Corazón de María village and Río Primero city) which were sampled during the low- and high-water flow periods. We analyzed: a) chemical and physical characteristics of water, sediments, and riparian soil; b) heavy metal content of water and sediments, and c) semi-volatile organic compounds in air. Besides, pollutant bioindicators such as fish assemblages, lichens (Usnea amblyoclada), vascular plants (Tradescantia pallida), and microorganisms (fecal coliform and Escherichia coli) were used to further assess the status of the river. All analyzed ecological compartments were affected by water pollution, particularly, fish assemblages, sediments and riparian soils by heavy metal and coliform bacteria. Moreover, we detected a possible contribution of sulfur and a high pollutant content in air that merit further research about other air-water exchanges. Accordingly, we strongly suggest that an action to restore or remediate the anthropic effect on the Suquía River be extended to all possible compartments along the river.

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INTRODUCTION: To determine a proper length of time for cleaning cloth usage, the present work aimed to evaluate bacterial multiplication in artificially contaminated cleaning cloths containing different amounts of organic matter. METHODOLOGY: Cloths containing 1%, 5%, and 10% of bovine albumin were contaminated with Salmonella enteritidis 3091/05, Escherichia coli ATCC 25972, Staphylococcus aureus ATCC 25923, and Shigella sonnei CC07. They were incubated for different time periods at 30°C. Microbial multiplication was evaluated by bacterial counts and the ATP bioluminescence increase was monitored at sampling points. An ampicillin-resistant recombinant HSα E. coli strain was used as a pathogen surrogate to investigate the potential of microbial cloth dispersion. RESULTS: None of the strains showed expressive growth up to two hours of incubation. At three hours, the microorganisms demonstrated a slight increase, with E. coli ATCC 25972 showing a significant increase in cells (p < 0.05). The ATP bioluminescence did not increase during the incubation period and confirmed the microbial count results, demonstrating that the amounts of organic matter tested did not interfere with bacterial multiplication during the first three to four hours of incubation. The dispersion experiment indicated that a cleaning cloth contaminated with 104 CFU/cm² was able to spread 10² CFU/cm² of recombinant E. coli onto a stainless steel surface. CONCLUSION: Based on these results, we suggest that an appropriate period of time for using disinfected cleaning cloths is around two hours, not exceeding three hours of usage.

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Exponer los resultados obtenidos en las evaluaciones realizadas a los medios de cultivo Agar azul bromotimol lactosa producido en BioCen, Cuba, y el comercializado por la Merck, Alemania, destinado para la diferenciación de microorganismos especialmente las enterobacterias, por su capacidad de fermentar la lactosa. Se ensayaron un total de 13 cepas certificadas y una aislada de muestra de agua, pertenecientes al Departamento de Investigaciones de Medios de Cultivo (BioCen). Las cepas evaluadas en ambos productos mostraron similitud en cuanto a su respuesta y a las características morfológicas de las colonias. Los valores del índice relativo de crecimiento (IRC) para 10 cepas superaron el 90 por ciento, resultando el 71,5 por ciento del total, mientras que solo 4 cepas reflejaron valores inferiores, resultando el 28,5 por ciento del total. Todas las cepas sobrepasaron el valor recomendado (> 70 por ciento), además las características culturales desarrolladas respondían a las reportadas. Los resultados alcanzados en la determinación del IRC demuestran la buena calidad del medio producido en BioCen frente a cepas de referencia, tomando como criterio el hecho de que todos los microorganismos ensayados mostraron valores del IRC superiores al valor recomendado.

To show results obtained in evaluations performed in agar blue bromotimol lactose culture media produced in BioCen, Cuba, and that marketed by Merck, Germany, created for microorganism differentiation, specially the Enterobacter ones, due to its ability for lactose fermentation. We assayed a total of 13 certified strains and another isolated from water sample, from Research Department of Culture Media (BeioCen). Values or Growing Relative Index for 10 strains were above 90 percent, with 71,5 percent of total, while that only 4 strains shoed lower values to a 28,5 percent of total. All strains exceeded the recommended value (>70 percent). Strains evaluated in both products showed similarity as regard its response and to morphologic features of colonies.

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