This study aimed to assess the behavior of endogenous microbiota (total mesophilic and psychrotrophic bacteria) during the ripening period and of L. monocytogenes and lactic acid bacteria (LAB) during storage at 5, 10, and 20 degrees C of artisanal Canastra cheeses packed in a silver nanoparticles packaging system using a predictive modeling approach. The tested packaging system did not influence the initial values of pH (around 5.0) or aw (around 0.95) over the storage. Based on the mathematical parameters obtained by the Weibull predictive model, the active packaging system tested did not inactivate L. monocytogenes during the storage period of artisanal Canastra cheeses. Nonetheless, the findings indicate that the polyethylene packaging system containing silver nano- particles (3000 ppm active based on silicon dioxide and silver) did not affect endogenous bacteria of Canastra cheese during ripening and storage, which opens the opportunity for the use of this material without compromising the role of these bacteria during cheese ripening, contributing to characteristics of the product's identity.

The present study aimed to assess the occurrence and counts of Staphylococcus aureus in Brazilian artisanal cheeses (BAC) produced in five regions of Brazil: Coalho and Manteiga (Northeast region); Colonial and Serrano (South); Caipira (Central -West); Maraj o (North); and Minas Artisanal cheeses, from Arax a, Campos das Vertentes, Cerrado, Serro and Canastra microregions (Southeast). The resistance to chlorine -based sanitizers, ability to attach to stainless steel surfaces, and antibiogram profile of a large set of S. aureus strains (n = 585) were assessed. Further, a total of 42 isolates were evaluated for the presence of enterotoxigenic genes ( sea, seb, sec, sed, see, seg, sei, sej , and ser ) and submitted to typing using pulsed -field gel electrophoresis (PFGE). BAC presented high counts of S. aureus (3.4 -6.4 log CFU/g), varying from 25 to 62.5%. From the S. aureus strains (n = 585) assessed, 16% could resist 200 ppm of sodium hypochlorite, whereas 87.6% produced strong ability to attach to stainless steel surfaces, corroborating with S. aureus ability to persist and spread in the environment. Furthermore, the relatively high frequency (80.5%) of multidrug-resistant S. aureus and the presence of enterotoxin genes in 92.6% of the strains is of utmost attention. It reveals the lurking threat of SFP that can survive when conditions are favorable. The presence of enterotoxigenic and antimicrobial -resistant strains of S. aureus in cheese constitutes a potential risk to public health. This result calls for better control of cheese contamination sources, and taking hygienic measures is necessary for food safety. More attention should be paid to animal welfare and hygiene practices in some dairy farms during manufacturing to enhance the microbiological quality of traditional cheese products.

This study aimed to determine the growth potential (delta) of L. monocytogenes (CLIST 3974, CLIST 3969, and CLIST 4162) and S. enterica [S. Typhimurium (ATCC SM 14028), S. Enteritidis (SM 64), and S. Montevideo (SM 129)] in the presence of a pool of lactic acid bacteria (LAB) with antimicrobial activity in Frescal and semi-hard Minas microcheeses. The delta was determined after storing Frescal cheese at 4 and 7 degrees C for 15 days and the and semi-hard Minas cheese during ripening (22 degrees C for 22 days). The delta of L. monocytogenes was significantly higher in Frescal Minas cheese with no added LAB (p > 0.05). On the other hand, in semi-hard cheese inoculated with LAB, inactivation of L. monocytogenes was observed. No significant differences were found in the delta of S. enterica in Frescal Minas cheese inoculated with LAB at 4 and 7 degrees C. S. enterica SM 14028 and SM 129 could grow in semihard cheeses non-inoculated with LAB, while when LAB was inoculated, S. enterica was inactivated. The findings of this study indicated that the delta of L. monocytogenes strains was more affected in cheeses inoculated with LAB than the delta of S. enterica.

This work aims to determine the mineral composition of Brazilian artisanal cheese (BAC) and classify the cheese types using chemometric techniques. Samples of BAC were analyzed and divided according to their region: Northeast cheeses (Coalho and Manteiga); Midwest cheeses (Caipira); Southeast cheeses (Arax & PRIME;a, Campo das Vertentes, Cerrado, Serra da Canastra and Serro) and South cheeses (Colonial and Serrano). Major (Ca, K, Mg, Na) and trace elements (Cu, Mn, Zn) content were determined by inductively coupled plasma optical emission spectrometer (ICP-OES). Artificial neural network (ANN), K-nearest neighbor (KNN), Random Forest (RF), Support vector machines with the radial kernel (SVM), and Learning Vector Quantization (LVQ) were used as supervised statistical methods to differentiate and classify the cheeses according to the type, and producing region. Coalho cheese showed the highest Ca, Cu, Mn, and Zn content with 91.09 mg g(-1), 63.51 mu g g(-1), 3.29 mg g(-1), and 137.51 mu g g(-1), respectively. Canastra cheese showed the highest K and Na content with 11.68 mg g(-1) and 96.98 mg g(-1), respectively. Cerrado cheese showed the highest Mg content (7.56 mg g(-1)). These differences in mineral content are explained by the type of cheese (fresh, ripened), producing region (climate, animal feeding, raw milk), and the technological process of cheese making (salts, metallic instruments). BAC is an essential source of minerals beneficial to health, and its authenticity is paramount for the consumer. RF and SVM classifiers were able to classify the cheese type dataset using the accuracy and Kappa coefficient as the figures of merit (Accuracy= 0.8347 and Kappa= 0.8105, Accuracy=0.8323 and Kappa=0.8078, respectively). For the classification of the production region, all algorithms presented excellent figures of merit. The classification performance can be characterized as outstanding for both cases. Such techniques guarantee the authenticity of Brazilian artisanal cheeses and the Protected Designation of Origin of the cheeses from each region, enhancing the added value of the cheese.

A broad survey on fatty acid profile and gross composition of different types of Brazilian artisanal cheeses (BAC; n = 402) produced in North, South, Northeast, Central-West, and Southeast regions of the country was performed. Results suggested that cheeses from North and Northeast regions have a different gross composition and fatty acid profile than the cheeses produced in the other regions. Butter cheese presented a higher fat content and a lower polyunsaturated fatty acid (PUFA) level, with a higher atherogenic index (AI). Maraj ' o cheese presented lower ash and protein content and higher fat content and monounsaturated fatty acid (MUFA) level, with consequent lower AI and thrombogenic index (TI) and higher desired fatty acid (DFA). Linear Discriminant Analysis (LDA) proportionated the cheeses' good discrimination based on geographical origin and free fatty acid composition.

This study aimed to evaluate technological (acidification, proteolysis, lipolysis, resistance to low pH, NaCl, and bile salts) and biopreservation (antimicrobial activity against foodborne pathogens) features of 1002 LAB by high throughput screening (HTS) methods. The LAB was isolated from 11 types of Brazilian artisanal cheeses (BAC) marketed in the main 5 producing regions. Remarkable intra-species variability in acidification rates have been found, which was most pronounced between isolates from Mina's artisanal cheeses, Caipira and Coalho cheeses. Lacticaseibacillus paracasei and Levilactobacillus brevis showed the fastest acidification rate; however, all isolates showed slower acidification rates than a lactococcal control strain (4.3 × lower). When testing inhibitory effects, > 75% of LAB isolates could inhibit the growth of Staphylococcus aureus ATCC 19095 and Listeria monocytogenes ATCC 7644. Two of these isolates, identified as Lactiplantibacillus plantarum and Lentilactobacillus buchneri, the sterile and neutral supernatants alone, were sufficient to inhibit L. monocytogenes growth. Principal component analysis (PCA) allowed the identification of functional groups based on proteolytic and lipolytic activity, osmotic stress resistance, and inhibition of L. monocytogenes. The type of cheese the isolates were recovered from influenced properties such as anti-listerial compounds and lipolytic enzyme production. The use of HTS and multivariate statistics allowed insights into a diverse set of LAB technological and biopreservation properties. These findings allow a profound knowledge of the heterogeneity of a large set of isolates, which can be further used to design starter cultures with varied and combined properties, such as biopreservation and technological features. Besides that, HTS makes it possible to analyze a vast panel of LAB strains, reducing costs and time within laboratory analysis, while avoiding the loss of information once all LAB are tested at the same time (differently from the traditional labor-intensive approach, in which a few numbers of strains is tested per time).

In this work, the amplicon sequencing of the 16 S rRNA gene was employed to investigate the bacterial diversity in ingredients, processing environment, and ripened cheeses collected from three farms producing Serra da Canastra artisanal cheese. The data obtained indicated a remarkable variability in the bacteria consortia of the milk, whey, and environmental samples collected in farms 1, 2, and 3, despite their location in the same city. On the other hand, the starter culture and final product (ripened cheese) presented more constant and similar microbiota no matter the farm. The findings suggest that Streptococcus and Lactococcus have competitive advantages throughout Serra da Canastra cheese-making/ripening, which is crucial for their high relative abundance in the final products. An exploratory assessment based on sequencing data available in the literature showed that the Serra da Canastra cheeses sequences clustered with specific cheese varieties that are also made from raw milk but ripened for very different periods. The findings of this study highlight that despite the variability of milk and whey microbiota among the three farms, the starter culture ("pingo") has strong relevance in shaping the microbiota of the final product.

A large variety of cheeses exist in Brazil, reflecting historical and cultural aspects. Brazilian artisanal cheeses present differences in the processing, ripening time (when applied), type of milk used, texture, size, shape, color, moisture content, flavor, the use or not of starter cultures, among others. This review describes the main artisanal cheeses produced in Brazil, focusing on general and particular characteristics associated with their making process and geographical identity. Overall, the high variability of the physicochemical data and deficiency of information on sensorial properties of Brazilian artisanal cheeses were noticed. On the other hand, culture-dependent methods were mostly used to expand the knowledge into the microbiology of these cheeses, whereas their microbial diversity has been recently discovered through the use of 16S rRNA gene sequencing-based methods. The certification of a geographical indication for Brazilian artisanal cheeses may encompass an essential milestone for adding value to these products. Regardless of their significance in the diet, culture, and economy of producing regions, taken together, the reviewed literature discloses the need of insightful studies to generate scientific data to support the expansion of the market, while ensuring the protection of historic aspects related to the production of Brazilian artisanal cheeses.

Chemical characteristics, mineral levels (Ca, Fe, K, Mg, Na, Zn, Cr, Cu, and Mn), fatty acid profile and volatile compounds of typically Brazilian cheeses (Minas Frescal, Minas Padrão, Prato and Coalho, n = 200, equally distributed) were investigated. The cheeses have proven to be a source of Ca, Cu and Zn (>15% RDI/30 g), with low atherogenic and thrombogenic indices, with ethanol as the main alcohol and butanoic acid as the main acid, and moderate to high sodium content. Minas Frescal cheese presented lower nutritional value (proteins, lipids, and minerals), while Prato cheese had a higher fatty acids concentration, including conjugated linoleic acid (0.013 g 100 g-1). Coalho cheese had a higher acetic acid level, while citric acid and lactic acid predominated in Minas Padrão cheese. The results provide essential information for Brazilian consumers, demonstrated that the manufacturing conditions are heterogeneous and suggested that a standardized manufacturing protocol for dairy processors is needed.

Dentre os agentes bacterianos amplamente distribuí­­dos no ecossistema aquático destacam-se os membros da famí­­lia Aeromonadaceae, podendo ser detectados tanto nos peixes como na água desse sistema. Este estudo foi realizado com o objetivo de verificar a ocorrência de bactérias do gênero Aeromonas em água de pisciculturas da Região da Baixada Ocidental Maranhense. Doze propriedades localizadas nos municí­­pios de Pinheiro, Palmeirí­¢ndia e Perimirim foram selecionadas. A coleta das amostras ocorreu no perí­­odo de outubro de 2008 a março de 2009. Foram coletadas quatro amostras de água dos viveiros de cada piscicultura, num total de 48 amostras. Em 100% das amostras analisadas foi confirmada a presença de bactérias do gênero Aeromonas. Os 89 isolados identificados foram classificados em três espécies: A. hydrophila (88%), A. caviae (9%) e A. veronii sobria (3%). As águas dos viveiros das pisciculturas analisadas apresentaram espécies de Aeromonas potencialmente patogênicas para os peixes e para o ser humano, representando risco para saúde da população consumidora dos organismos cultivados nessas propriedades.

Artisanal raw milk cheeses are highly appreciated dairy products in Brazil and ensuring their microbiological safety has been a great need. This study reports the isolation and characterization of lactic acid bacteria (LAB) strains with anti-listerial activity, and their effects on Listeria monocytogenes during refrigerated shelf-life of soft Minas cheese and ripening of semi-hard Minas cheese. LAB strains (n = 891) isolated from Minas artisanal cheeses (n = 244) were assessed for anti-listerial activity by deferred antagonism assay at 37 °C and 7 °C. The treatments comprised the production of soft or semi-hard Minas cheeses using raw or pasteurized milk, and including the addition of selected LAB only [Lactobacillus brevis 2-392, Lactobacillus plantarum 1-399 and 4 Enterococcus faecalis (1-37, 2-49, 2-388 and 1-400)], L. monocytogenes only, selected LAB co-inoculated with L. monocytogenes, or without any added cultures. At 37 °C, 48.1% of LAB isolates showed anti-listerial capacity and 77.5% maintained activity at 7 °C. Selected LAB strains presented a bacteriostatic effect on L. monocytogenes in soft cheese. L. monocytogenes was inactivated during the ripening of semi-hard cheeses by the mix of LAB added. Times to attain a 4 log-reduction of L. monocytogenes were 15 and 21 days for semi-hard cheeses produced with raw and pasteurized milk, respectively. LAB with anti-listerial activity isolated from artisanal Minas cheeses can comprise an additional barrier to L. monocytogenes growth during the refrigerated storage of soft cheese and help shorten the ripening period of semi-hard cheeses aged at ambient temperature.

Brazilian artisanal cheeses are characterized by the use of raw milk and in some cases, natural starter cultures, known as "pingo", as well as following simple and traditional manufacturing technology. In this study, a largescale screening of the microbial ecology of 11 different types of artisanal cheeses produced in five geographical areas of Brazil was performed. Besides, the specific origin-related microbial signatures were identified. Clear geography- and technology-based differences in the microbiota were observed. Lactic acid bacteria dominated in all cheeses although Enterobacteriaceae and Staphylococcus also occurred in North, Northeast and Central cheeses. Differences in the lactic acid bacteria patterns were also highlighted: Streptococcus, Leuconostoc, Lactococcus and Lactobacillus were differently combined in terms of relative abundance according to product type and region of production. This study provides a comprehensive, unprecedented microbiological mapping of Brazilian cheeses, highlighting the impact of geographical origin and mode of production on microbial diversity. The results obtained will help to plan an evaluation of microbial contamination sources that will need to be studied for the improvement of cheese quality and safety.

In this study the growth potential (δ) of Listeria monocytogenes in six formulations of probiotic (Lactobacillus acidophilus and Bifidobacterium lactis) reduced-sodium cottage cheese containing or not NaCl, combined with KCl and/or MgCl2 stored under different temperature conditions was assessed. Reduced-sodium cottage cheeses were inoculated with L. monocytogenes (approximately 103CFU/g) and then stored at 4°C (I), 30% of the shelf life at 4°C and the remaining 70% at 12°C (II) and 12°C (III) for 28days. A growth potential (δ) above 0.5logCFU/g indicated that the formulation was capable of supporting the growth of L. monocytogenes. The growth potential (δ) of L. monocytogenes at 4°C (I) was between 0.5 and 0.8logCFU/g. Higher growth potentials (1.1–1.6logCFU/g) were observed when the cottage cheeses were stored for 30% of the shelf life at 4°C followed by storage for 70% at 12°C (II). In the scenario III (28days at 12°C), L. monocytogenes was only able to grow in the formulation with 100% NaCl and no probiotics (F1), while in F2–F6 (probiotic formulations with different combinations of NaCl, KCl, MgCl2) the populations of this bacterium were below the quantification level (<1logCFU/g). Independent of the storage scenarios studied, strict conditions of hygiene during processing and use of raw materials of excellent microbiological quality are key-factors for ensuring the safety of this product as L. monocytogenes will be able to grow at low storage temperature.

O gênero bacteriano Yersinia compreende 14 espécies (BOTTONE et al., 2005), entre as quais, quatro são consideradas patogênicas aos animais e/ou aos humanos, entre elas, a Yersinia enterocolitica (ORTIZ MARTÍNEZ, 2010). Apesar de sua distribuição heterogênea, (LYNCH et al., 2006; BONARDI et al., 2010), a maior fonte de infecção de Y. enterocolitica para os humanos é o suíno e a principal via de transmissão, a carne suína e seus produtos contaminados (FREDRIKSSON-AHOMAA et al., 2011; DRUMMOND et al., 2012). Segundo Howard et al. (2006) várias doenças podem ser causadas pela Y. enterocolitica em humanos, desde uma diarréia moderada até complicações mais graves como, adenite mesentérica e artrite reumatóide. Com o objetivo de determinar a ocorrência e o isolamento desse agente na linha de abate de suínos, foram coletadas amostras de tecidos biológicos, excrementos e suabes de carcaças de suínos ao abate e de facas em um matadouro-frigorífico supervisionado pelo Serviço de Inspeção Estadual do estado de São Paulo (SISP). A partir de 25 animais, foram analisadas 175 amostras compostas de línguas, tonsilas, linfonodos submandibulares, linfonodos mesentéricos, suabes de carcaças, conteúdo retal e suabes de facas utilizadas pela inspeção. Para o isolamento, empregou-se a metodologia preconizada pela International Organization for Standardization , pelo método ISO 10273 (ISO, 2003). Y. enterocolitica foi isolada em 5 amostras de tonsilas, 4 de línguas, 2 de linfonodos submandibulares, 2 de facas e 1 de linfonodo mesentérico, totalizando 14 amostras positivas (8%) das 175 coletadas. Apenas os isolados a partir das facas foram considerados patogênicos: Y. enterocolitica biotipo 4 sorotipo O:3. Dessa maneira, deve-se considerar a faca utilizada pela inspeção um importante fômite para a disseminação do agente para a carcaça do próprio animal portador como para outras carcaças de animais não portadores, por contaminação cruzada. O isolamento do agente em amostras de animais clinicamente saudáveis representa um risco para a saúde pública, pela possibilidade de ingestão de carne suína contaminada por Y. enterocolitica . SUMMARY The bacterial genus Yersinia includes 14 species (BOTTONE et al., 2005), of which four are considered pathogenic to animals and/or humans, among them, Yersinia enterocolitica (ORTIZ MARTINEZ, 2010). Despite its heterogeneous distribution, (LYNCH et al., 2006; BONARDI et al., 2010), pigs constitute the major source of infection of Y. enterocolitica in humans while the main route of transmission is the pork and contaminated products (FREDRIKSSON-AHOMAA et al., 2011; DRUMMOND et al., 2012). According to Howard et al. (2006), various diseases can be caused by Y. enterocolitica in humans, ranging from a mild diarrhea to severe complications such as mesenteric adenitis and rheumatoid arthritis. In order to determine the occurrence and to isolate this agent in the pig slaughtering process, samples of biological tissues were collected, as well as excreta and swabs of pig carcasses at slaughter and of slaughter knives from a slaughterhouse subjected to sanitary inspection by the State Inspection Service of the São Paulo State (SISP). A total of 175 samples from 25 animals consisting of tongues, tonsil, submandibular and mesenteric lymph nodes, carcass swabs, rectal contents and swabs of the knives used for inspection were analyzed. The methodology recommended by the International Organization for Standardization, method ISO 10273 (ISO, 2003), to isolate Y. enterocolitica was used. The bacteria was isolated in 5 samples of tonsils, 4 tongues​​, 2 submandibular lymph nodes, 2 knives and 1 mesenteric lymph node, totaling 14 positive samples (8%) of the 175 collected. Only the isolates from the knives were considered pathogenic Y. enterocolitica , biotype 4, serotype O: 3. Thus, the knife used for inspecting the meat should be considered an important fomite for the dissemination of the agent to the carcass of the contaminated animal itself and to other non-contaminated animal carcasses through cross-contamination. The isolation of the agent in samples from clinically healthy animals poses a risk to public health, due to the possibility of ingesting pork infected with Y. enterocolitica.

Haja vista que os alimentos de origem animal, entre eles a carne e produtos cárneos de suínos, são considerados importantes transmissores de Salmonella sp. para o consumidor, o objetivo do presente estudo foi determinar a prevalência de Salmonella sp. em língua, tonsilas, linfonodos submandibulares, linfonodos mesentéricos, superfície de carcaças e de reto de suínos abatidos sob inspeção estadual e também na superfície de lâmina de facas utilizadas na inspeção. Para o isolamento utilizou-se água peptonada a 0,1% no pré- enriquecimento e caldos selenito cistina e Rappaport-Vassiliadis no enriquecimento seletivo. O plaqueamento foi realizado em ágares MacConkey e verde-brilhante e a identificação presuntiva em ágar TSI e LIA. A caracterização final foi realizada através de sorotipagem. Dos 25 animais amostrados, Salmonella Anatum foi isolada na língua de 2 animais, correspondendo a 8%. Considerando que a retirada da língua não é um procedimento obrigatório e pode entrar como matéria-prima na produção de alguns alimentos, como mortadela e salsicha, a presença de Salmonella sp. representa um fator de risco para a segurança alimentar. Apesar da baixa prevalência, deve-se considerar a possibilidade de contaminação cruzada com outras matérias-primas, ambiente e equipamentos. SUMMARY Considering that foods of animal origin, such as pork and pork products are important carriers of Salmonella sp., the objective of this study was to determine the prevalence of Salmonella sp. in pork tongue, tonsils, mandibular and mesenteric lymph nodes, carcass surface and rectum, as well as on the blade surface of knives used on the inspection since the pigs were slaughtered under state inspection. For the isolation, 0.1% peptone water was used for pre-enrichment, while Rappaport-Vassiliadis and selenite cystine broths were used as selective enrichment. The plating was done on MacConkey and brilliant green agar and the presumptive identification on TSI and LIA. The final characterization was performed by serotyping. From the 25 animals sampled, Salmonella anatum was isolated in the tongue of two animals, corresponding to 8%. The presence Salmonella sp. should be treated as a risk factor for food safety, since tongue removal is not a mandatory procedure and may be used as a raw material in some processed foods, such as sausage and bologna. Despite the low prevalence, the possibility of cross-contamination to other raw materials, environment and tools should be taken into consideration.

RESUMO O gênero Aeromonas compreende espécies consideradas importantes patógenos para os seres humanos, sendo que a principal ação patogênica delas corresponde às gastroenterites. Tendo em vista sua importância como patógeno de origem alimentar, a ocorrência de Aeromonas spp. foi estudada em carcaças bovinas e ambiente do abatedouro em uma indústria do Estado de São Paulo, com o intuito de definir a possível origem comum dessas bactérias no ambiente do frigorífico através de métodos moleculares. Foram colhidas 15 amostras de 19 pontos, totalizando 285 unidades. As amostras foram colhidas dos seguintes pontos: pele seca e úmida, superfície muscular das carcaças durante a toalete e das carcaças resfriadas, mãos dos funcionários antes e durante o trabalho na sala de abate e câmara de resfriamento, facas, parede e piso da câmara de resfriamento, água (clorada, não clorada e residuária da lavagem das carcaças), carne, conteúdo intestinal e ambiente da sala de abate. Foi realizada a caracterização do gênero e os isolados foram analisados pelas técnicas de REP (Repetitive Extragenic Palindromic) e ERIC (Enterobacterial Repetitive Intergenic Consensus)-PCR. Foi encontrada similaridade ? 99% somente entre um isolado de superfície muscular de uma carcaça resfriada com um isolado de mão. As técnicas moleculares não possibilitaram a identificação precisa da origem das bactérias na indústria, mas possibilitaram inferir que os manipuladores podem atuar como disseminadores delas no ambiente de abate.

RESUMO O gênero Aeromonas compreende espécies consideradas importantes patógenos para os seres humanos, sendo as gastroenterites as infecções mais comumente atribuídas a estas bactérias. Tendo em vista sua importância como patógeno de origem alimentar, a ocorrência deAeromonas spp. foi estudada em carcaças bovinas e ambiente do abatedouro em uma indústria do Estado de São Paulo. Foram colhidas 285 amostras de 19 locais. Foi realizada a contagem direta por semeadura em meio seletivo, caracterização bioquímica das espécies após enriquecimento seletivo e teste de sensibilidade a antimicrobianos. A contagem direta permitiu a quantificação dessas bactérias em apenas 12 amostras, variando de 0,5 a 9,2 x 100 UFC/cm2, sendo cinco delas de ambiente, com populações que variaram de 1,0 x 100 a 3,0 x 100 UFC/placa. Entretanto, após o enriquecimento seletivo, Aeromonas spp. foram isoladas de 38 amostras que, somadas às amostras de ambiente não submetidas ao enriquecimento, forneceram 62 isolados para análise. A caracterização bioquímica das espécies permitiu verificar a ocorrência de 59 isolados de A. caviae, um de A. sobria, um de A. trota e um de A. schubertii. O teste com antimicrobianos revelou resistência de todos os isolados pela ampicilina e cefalotina, enquanto, para os demais antimicrobianos, esta foi variável. A resistência da totalidade dos isolados a determinados antimicrobianos indica que estes devem ser utilizados criteriosamente com a finalidade de evitar o surgimento precoce de cepas deAeromonas spp. multirresistentes. Ainda, a maior prevalência deA. caviae deve ser considerada relevante, pois trata-se de uma das espécies causadoras de gastroenterite em humanos.

Among the widely distributed bacterial agents in the aquatic ecosystem, can be outstanding the family Aeromonadaceae detected such in fish as in the water of this system. This study intended to verify the occurrence of Aeromonas spp. in pond water of fishfarms located in Occidental Lowland Region of Maranhao. Twelve properties located in Pinheiro, Palmeirandia and Perimirim cities had been selected. The harvest of the samples occurred in the period from October, 2008 to March, 2009. A total of 48 pond water samples were harvested. Four water samples of each fishfarm. Aeromonas were confirmed in 100% of the samples. The 89 isolate identified had been classified in three species, A. hydrophila (88%), A. caviae (9%), A. veronii sobria (3%). The pond waters of the fishfarms analyzed presented contamination with potentially pathogenic species of aeromonas which represents risk for people's health, especially for the organisms cultivated in these properties.