Atividade antagonista in vitro de bactérias ácido láticas isoladas de queijo de coalho artesanal do Sertão paraibano frente a microrganismos indicadores / Antagonist activity in vitro of lactic acid bacteria isolated from coalho cheese from Sertão paraibano front microorganisms indicators

Bactérias ácido láticas (BAL) produzem substâncias inibitórias de patógenos e deteriorantes de alimentos e isso tem despertado interesse sobre seu uso na preservação e na segurança sanitária desses produtos. Assim, o estudo foi realizado com o objetivo de avaliar a atividade inibitória de Streptococcus infantarius subsp. infantarius isoladas de queijo de coalho artesanal do Sertão da Paraíba frente a microrganismos indicadores. A avaliação do potencial antagônico foi realizada pela técnica de difusão em disco frente à estirpe reveladora Escherichia coli, isolada das mesmas amostras de queijos e frente ao patógeno de referência Escherichia coli ATCC 3539. Das 11 estirpes analisadas, 81,8% foram capazes de inibir o microrganismo indicador isolado dos mesmos queijos de coalho, enquanto 36,4% das bactérias láticas apresentaram inibição frente ao patógeno de referência. Conclui-se que as cepas Streptococcus infantarius subsp. infantarius isoladas de queijos de coalho do Sertão da Paraíba apresentam potencial antagônico e podem assegurar a qualidade microbiológica de alimentos fermentados, inclusive o queijo de coalho.(AU)

Lactic acid bacteria (BAL) produce pathogen inhibiting and food damaging substances and this has raised interest in their use in the preservation and health safety of these products. Thus, the study was carried out with the objective of evaluating the inhibitory activity of Streptococcus infantarius subsp. infantarius isolated from artisanal coalho cheese from Sertão da Paraíba against indicator microorganisms. The evaluation of the antagonistic potential was performed using the disk diffusion technique against the Escherichia coli revealing strain, isolated from the same cheese samples and against the reference pathogen Escherichia coli ATCC 3539. Of the 11 strains analyzed, 81.8% were able to inhibit the indicator microorganism isolated from the same coalho cheeses, while 36.4% of the lactic acid bacteria showed inhibition compared to the reference pathogen. It is concluded that the strains Streptococcus infantarius subsp. infantarius isolated from coalho cheeses from Sertão da Paraíba have antagonistic potential and can ensure the microbiological quality of fermented foods, including coalho cheese.(AU)

Socio-environmental and microbiological assessment of the river Piancó, Pombal, Brazil / Avaliação socioambiental e microbiológica do rio Piancó, Pombal-Paraíba

The River Piancó in the municipality of Pombal on the western stretch of the state of Paraíba, Brazil, receives contaminated effluents. Current assay evaluates the microbiological quality of the river water and analyzes the social and environmental aspects of the riverine community with regard to the water and its use of the river. The water´s microbiological quality was verified at four sites on the river in five two- monthly collections throughout the year (totaling 20 samples) for the following analyses: Most Probably Number (MPN), Total (TC) and Fecal Coliform (FC) and identification of Escherichia coli. The social and environmental aspects were assessed by a 15-question questionnaire given to thirty homes. Results report Fecal Coliforms (> 240 to > 1,100 MPN 100 mL-1), Total (> 93 to > 1,100 MPN 100 mL-1) and high concentrations of E. coli (> 898 to > 1,100 UFC 100 mL-1) in all the sampling sites. The river is frequented by the riverine people for home consumption, recreation and fishing. Conditions of the River Piancó, especially in the stretch that margins the town of Pombal, are highly critical and exceed the limits of current Brazilian legislation with regard to drinking and swimming conditions.

O Rio Piancó, na sua porção oeste do Estado da Paraíba, no município de Pombal, recebe efluentes que têm causado a sua contaminação. Este trabalho objetivou avaliar a qualidade microbiológica deste rio e analisar aspectos socioambientais da comunidade ribeirinha sobre a água e o uso do rio. A qualidade microbiológica foi verificada em quatro pontos do rio, em cinco coletas bimestrais ao longo do ano (20 amostras no total), para análises do Número Mais Provável (NMP), Coliformes Totais (CT) e Fecais (CF) e identificação da Escherichia coli. A avaliação socioambiental foi por meio da aplicação de um questionário socioambiental constituído por 15 perguntas, aplicados a uma população de 30 residências. Os resultados reportaram a presença de Coliformes Fecal (> 240 a > 1.100 NMP 100 mL-1), Total (> 93 a > 1.100 NMP 100 mL-1) e altas concentrações de E. coli (> 898 a > 1.100 UFC 100 mL-1) em todos os pontos amostrais. O rio é utilizado pelos moradores ribeirinhos, principalmente, para o consumo doméstico, a recreação primária e a pesca. A atual situação do Rio Piancó, na porção em que margeia a cidade de Pombal é crítica, ultrapassando todos os limites da legislação brasileira vigente quanto à potabilidade e balneabilidade da água do rio.

The sensitivity of bacterial foodborne pathogens to Croton blanchetianus Baill essential oil

The aim of this study was to assess the activity of essential oil extracted from the leaves of C. blanchetianus Baill, popularly known as "marmeleiro", in inhibiting the growth and survival of pathogenic microorganisms in food by determining their survival in vitro and by observing the behaviour of Listeria monocytogenes inoculated into a food model (meat cubes) that was stored at refrigeration temperature (7 ± 1 ºC) for 4 days. The results indicated a bactericidal effect against Aeromonas hydrophila and Listeria monocytogenes and bacteriostatic action against Salmonella Enteritidis. A bacteriostatic effect on meat contaminated with L. monocytogenes was found for all concentrations of essential oils tested. These results showed that essential oil from the leaves of C. blanchetianus Baill represents an alternative source of potentially natural antimicrobial agents that may be used as a food preservative.