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RESUMOForam analisadas 30 amostras de carne bovina moída resfriada, previamente embaladas, provenientes de estabelecimentos comercias do município de Niterói, RJ, com o objetivo de se observar a freqüência de bactérias do gênero Listeria spp. Utilizou-se para isto a metodologia revisada do USDA. 50% das amostras analisadas apresentaram contaminação por Listeria spp., sendo a L. innocua (SEELIGER & SCHOOFS, 1979) a espécie isolada em maior número, seguida pela L. monocytogenes (MURRAY et al., 1926;PIRIE, 1940). Na tipificação sorológica, observou-se maior prevalência de L. monocytogenes pertencente ao sorotipo 4b (50%), porém o sorotipo ½ c também foi identificado. As amostras que apresentaram-se contaminadas com L. monocytogenes, caracterizam-se como potencialmente capazes de ocasionar enfermidades transmitidas por alimentos.Termos para indexação: Microbiologia, carne vermelha, listeriose. ABSTRACTThirty bovine ground meat samples from several markets from Niterói, RJ, were analyzed, in order to observe the frequency of bacterias of the genus Listeria spp. A USDA revised methodology as applied in this research. Fifty percent of the samples were contaminated by Listeria spp.. L. innocua species as the most isolated, followed by L. monocytogenes. In serological typification, the greatest prevalence was that of sorotype 4b L. monocytogenes (50%), however the ½ c sorotype was also identified. Samples contaminated by L. monocytogenes are potentially capable of causing diseases through food consumption. (MURRAY et al., 1926;PIRIE, 1940), considerada a espécie patogênica para homens e animais, contém os sorovares ½ a, 1/2b, 1/ 2c, 3a, 3b, 3c, 4a, 4b, 4c, 4e, 7 (SEELIGER & JONES, 1996).

ResumoCom o aumento do uso de antimicrobianos como promotores de crescimento e até mesmo com fins terapêuticos na criação de animais de produção, existe o interesse global referente ao consumo de baixos níveis de resíduos de antimicrobianos em alimentos e os efeitos destes na saúde humana. A ingestão de alimentos contendo resíduos de fármacos antimicrobianos pode ocasionar resistência bacteriana aos antimicrobianos utilizados rotineiramente na terapêutica humana, dificultando o tratamento de enfermidades infecciosas humanas. Neste experimento foi realizado o teste de sensibilidade aos antimicrobianos em cepas de Listeria spp. isoladas a partir de amostras de carnes bovinas, através da metodologia descrita pelo NCCLS em 2003. De acordo com os resultados, todas as cepas isoladas foram resistentes à maioria dos antimicrobianos testados. As cepas de L. monocytogenes foram resistentes à gentamicina, cefoxitina, ampicilina, clindamicina, oxaciclina e sulfazotrim. As cepas de L. innocua isoladas foram resitentes à gentamicina, cefoxitina, tetraciclina, vancomicina, oxaciclina e clindamicina. Palavras-chave:Antimicrobianos. Alimentos. Listeriose. IntroduçãoA utilização de antimicrobianos gerou grande otimismo em relação à prevenção e ao tratamento dos processos infecciosos. Entretanto, o uso exagerado e nem sempre criterioso ou racional dos antimicrobianos e quimioterápicos trouxe dificuldades, sendo a maior delas representada pela progressiva resistência bacteriana aos fármacos. 1 As bactérias podem ser classificadas em sensíveis e resistentes aos antimicrobianos. Em geral, classificam-se como resistentes, as bactérias que crescem "in vitro", nas concentrações médias que os antimicrobianos atingem no sangue, quando administrados por via oral. São sensíveis as que não crescem nestas concentrações. 2 De acordo com Trabulsi e Toledo 2 , a resistência bacteriana pode ser natural ou adquirida. A natural corresponde a uma característica da espécie bacteriana, e a adquirida, à característica de uma ou mais amostras da espécie. A aquisição de resistência por uma célula bacteriana sensível é sempre decorrente de uma alteração genética.O gênero Listeria apresenta uma susceptibilidade uniforme aos antimicrobianos contra bactérias Gram positivas. 3 Os antimicrobianos mais indicados no tratamento da listeriose são : tetraciclina, coumercina, rifampicina, cloranfenicol, eritromicina e ampicilina, sendo esta última adicionada de um antibiótico aminoglicosídio. 4,5 Marth 6 relata que a maioria das cepas é sensível à tetraciclina, cloranfenicol, eritromicina e cefalotina. Ampicilina, rifampicina, ou penicilina associada com gentamicina são os antimicrobianos de escolha para o tratamento de listeriose. 7 A associação de trimetoprim com uma sulfonamida como a sulfametoxazole no co-trimoxazole, é considerada como uma segunda opção para o tratamento. 8 Para o tratamento da bacteremia e da mulher grávida com listeriose, utiliza-se a vancomicina e a eritromicina, respectivamente. 7 Mesmo com o uso destes fármacos, a terapia com antimicrobian...

Nos tempos modernos, uma das grandes preocupações da comunidade científica é a grande probabilidade de colonização da mucosa intestinal do homem, através da ingestão de alimentos contaminados, por microrganismos extremamente resistentes à maioria dos antimicrobianos utilizados no tratamento de enfermidades.O uso de antibióticos foi revolucionário no tratamento das infecções bacterianas e crucial para a redução da mortalidade (NATARO; KAPER, 1998). Entretanto, seu uso abusivo e indiscriminado, tanto em humanos (CHUC et al., 2002) quanto na medicina veterinária (COSTA et al., 2006), pode ter contribuído para o aumento da resistência antimicrobiana (CHUC et al., 2002). Essa resistência relaciona-se, ainda, à produção de enzimas (β-lactamases e β-lactamases de amplo espectro), que atuam sobre a estrutura das penicilinas, inativando-as, característica que constitui um mecanismo de defesa desses agentes. Emery e Weymouth (1997) constataram que a síntese dessas enzimas era codificada por genes presentes AbstractForty-four strains of Escherichia coli isolated from mussel samples collected in the city of Niterói, State of Rio de Janeiro, were evaluated in terms of antimicrobial sensitivity. Twenty-four antimicrobials were tested, and different standards of behavior could be observed. All strains evaluated presented total sensitivity to only 41.66% of the antimicrobials (R, Ac, C, To, Fx, Cz, Ct, NT, Cp, and GE) and total resistance to 4.16% of the antimicrobials (Ca). The strain number eighteen presented sensitivity to 95.83% of the antimicrobials, whereas the strain number thirty presented resistance to 41.66% of the antimicrobials. Based on the results obtained, it is important to consider the health risk posed by raw fish consumption, especially filter-feeding bivalves, contaminated by microorganisms resistant to different antimicrobials since they may be involved in processes of human reinfection causing gastroenteritis.

Foodborne disease caused by microorganisms is a problem of public health. Minas soft cheese is a national product manufactured using simple technology; it has high level of acceptance in the country making its production an important economic activity. Many microorganisms may be present in foods including the bacterium Escherichia coli (E. coli). Overall, E. coli is a harmless commensal bacterium; however, some strains may have a pathogenic potential. Several outbreaks of foodborne diseases associated with consumption of contaminated cheese have been reported, and the presence of pathogenic strains of E. coli has increased. The objective of this study was to isolate, evaluate the antimicrobial susceptibility, and characterize, by Multiplex PCR, the pathogenic E. coli strains isolated from Minas cheese commercialized in Rio de Janeiro. Thirty samples were analyzed and five strains of E. coli (EPEC) were identified. The assessment of antimicrobial susceptibility revealed 40% of the isolates resistant to ampicillin and 40% with intermediate resistance to ampicillin-sulbactam combination. These findings are a warning signal to health authorities since Minas cheese is a ready to eat food product, and therefore should not pose health risks to the population.

The aim of this study was to evaluate the effect of gamma irradiation (1, 2 and 3 kGy) on the bacteriological quality and sensory perception of refrigerated raw whole milk. Moreover, physiochemical and bacteriological parameters were monitored during 60 days of storage at 4C. All of the irradiated samples, mainly 2 and 3 kGy, exhibited a lower (P < 0.05) bacterial load than the nonirradiated samples. During storage, the mesophilic count and titratable acidity did not increase in the irradiated samples. The consumers were able to differentiate all of the irradiated samples from the control group (P < 0.05); however, positive attributes were used to describe the irradiated samples. The present study indicates that the 2 kGy irradiation dose improved the bacteriological quality of raw whole milk and likely did not negatively affect sensory characteristics by maintaining a constant mesophilic count and titratable acidity over the 60 days of refrigerated storage. PRACTICAL APPLICATIONSThe prevalence of foodborne diseases and huge economic losses from food industries in developing countries has markedly increased. Taking into account the dairy products, raw milk represents the main source of foodborne infections. To investigate an alternative conservation method, three gamma irradiation doses (1, 2 and 3 kGy) were applied in refrigerated raw whole milk. After, bacteriological and sensory qualities of this milk were investigated. In addition, mesophilic count and titratable acidity were analyzed during 60 days of storage under refrigeration (4 ± 1C). On 0 day, all irradiation doses decreased (P < 0.05) the bacterial load of raw whole milk compared with nonirradiated samples. Moreover, both parameters evaluated during storage period (mesophilic bacterial count and titratable acidity) were stable in samples treated with 1, 2 and 3 kGy. However, rancid odors and flavors were perceived on the samples irradiated with 3 kGy. Therefore, in our study, the 2 kGy dose was recommended for raw whole milk because of the positive effects on bacterial quality and minimal sensory changes.

Listeria monocytogenes has created great concern among health authorities since the 1980's because of an increase in the number of outbreaks of human listeriosis and its possible association with contaminated food. There are no reports of an association between listeriosis and food contamination in Brazil, although recent studies have identified this bacteria in poultry meat. The goals of the present study were to investigate the incidence of L. monocytogenes in commercial turkey meat, to evaluate the bacterial sensitivity to antimicrobial agents, and to conduct serology tests of L. monocytogenes isolates. Forty samples of turkey meat were studied: 10 samples of whole turkey blanquet, 10 samples of sliced turkey blanquet, 10 samples of whole turkey ham, and 10 samples of sliced turkey ham. These samples were inspected by the Brazilian Federal Inspection Service and were retailed in the city of Niterói. Bacteria were not detected in whole products; however, incidence was high in sliced products (80% in blanquet and 90% in ham). Isolates of L. monocytogenes, which belonged to serovars 4b, ½ c, ½ b, and ½ a, were found to be sensitive to all antimicrobial agents tested. The most common serovars were those known to cause listeriosis. Despite the lack of isolation of L. monocytogenes in whole meat, its presence in sliced turkey meat indicates that improved sanitation in the processes of slicing and packaging is urgently needed.

ResumoVisando conhecer a segurança do produto "sashimi" de salmão fornecido em restaurantes, e dos riscos potenciais ao consumidor, a pesquisa objetivou avaliar a ocorrência de Vibrio parahaemolyticus e de Salmonella spp na matéria-prima, no produto final antes de sua exposição à venda e após sua exposição ao cliente; e de Salmonella spp nas mãos dos manipuladores, em dois restaurantes (RI e RII). Os estabelecimentos foram classificados pelas diferentes condições de higiene e climatização do ambiente de manipulação, sendo RII considerado o melhor. Foi verificada a ausência de Vibrio parahaemolyticus em 100% das amostras; presença de Salmonella spp. em 12,5% do total de amostras analisadas, sendo todas estas pertencentes a RII: 25% estava presente na mão do manipulador e 75%, presente na matéria-prima e produtos finais. Através dos resultados da pesquisa pôde-se concluir que ambos os estabelecimentos estavam em conformidade com a RDC 12 de 2001 da ANVISA para Vibrio parahaemolyticus, mas RII enquadrou-se fora dos padrões estabelecidos quanto à presença de Salmonella spp. O resultado sugere que RII necessita da adoção eficaz de práticas higiênicosanitárias na elaboração de "sashimi" para eliminar a presença de Salmonella spp., que é um risco potencial à saúde do consumidor.Palavras-chave: pescado, "sashimi", Vibrio parahaemolyticus, Salmonella spp. AbstractIn order to know the quality and safety of the sashimi salmon comes in restaurants and its potential risks to the consumer, this research aimed evaluated the occurrence of Vibrio parahaemolyticus and Salmonella in raw material, on the final product before its exposure to sales and after exposure to the client and Salmonella spp in the hands of handlers, in two restaurants (RI and RII). The difference between the places was classified by the conditions of environmental air handling and hygiene, and RII was considered the best. It was verified the absence of Vibrio parahaemolyticus in 100% of samples, the presence of Salmonella spp. in 12.5% of total samples analyzed, with absence in all samples of RI and presence in 25% of samples at RII. In this proven contamination, 25% was present in the hands of the handlers and 75% present in the raw material and finished products. Based on the results of research it was concluded that both establishments were in compliance with the legislation for the first microorganism, but RII, although had the best conditions of climate and hygiene, framed outside of the microbiological standards established by the presence of Salmonella spp. The results suggest that the establishment in violation of the law requires the efficient and effective adoption of adequate sanitary practices in preparation of sashimi to avoid the presence of Salmonella spp., which can pose a risk to consumer health.