RESUMO.-[Ocorrência e caracterização de isolados de Campylobacter spp. em cães, gatos e crianças.] Com o objetivo de melhorar o entendimento das infecções porCampylobacter spp. em cães, gatos e crianças no Brasil, foram avaliadas 160 amostras fecais de crianças e 120 swabs retais de pets (103 cães e 17 gatos). Do total das amostras das crianças, 6,87% foram positivas para Campylobacter spp. e em cães e gatos a positividade foi de 18,3%. Das 33 amostras positivas para Campylobacter spp., 57,6% foram identificadas como C. jejuni e 33,4% foram identificadas como C. coli. Mais de 50% das amostras isoladas de pets foram resistentes a ceftiofur, sulphazotrim, norfloxacina e tetraciclina. Em crianças, a maioria das amostras foi resistente a amoxilina, cefazolina, ceftiofur, eritromicina e norfloxacina. De 19 isolados de C. jejuni, 11 isolados de crianças e cinco (5) de cães tinham dois (2) dos quatro (4) genes de virulência flaA, pldA, cadF or ciaB. Associação positiva entre a presença de Campylobacter spp. e diarreia em cães e gatos foi observada em animais desverminados e com hemograma sugestivo de infecção bacteriana. Também houve associação positiva entre a presença dos genes de virulên-cia e a ocorrência de diarreia, e entre o uso de antibióticos e a positividade para Campylobacter spp. em suabes fecais de pets. To improve the understanding of implications of Campylobacter spp. infections in pets and children of different environments were analysed 160 faecal samples from children and 120 from pets (103 dogs and 17 cats). Campylobacter spp. were detected in 6.87% of the children and in 18.3% of the dogs and cats. From 33 stool samples positive for Campylobacter spp., 57.6% were identified as C. jejuni, and 33.4% were identified as C. coli. More than 50% of the isolates in pets were resistant to ceftiofur, sulphazotrim, norfloxacin and tetracycline. In humans, most of the isolates were resistant to amoxicillin, cefazolin, ceftiofur, erythromycin and norfloxacin. From 19 isolates of C. jejuni, 11 isolates from children and 5 from dogs contained two to four of the virulence genes flaA, pldA, cadF or ciaB. We found an association between the presence of virulence genes and diarrhoea. Furthermore, an association was observed between the presence of Campylobacter spp. and diarrhoea in dewormed pets with blood picture suggestive of bacterial infection, and the therapeutic use of antibiotics was associated with more positive detection of Campylobacter spp. in the faeces of pets. Our data indicate that virulent strains of Campylobacter spp. can be risk factor to diarrhoea in animals, and that high resistance to antimicrobial agents is common in pets. de Campylobacter spp. são fatores de risco para diarreia em cães e a resistência antimicrobiana é comum em isolados de cães.

The saccharification of sugarcane bagasse by enzymatic hydrolysis is one of the most promising processes for obtaining fermentable sugar to be used in the production of second-generation ethanol. The objective of this work was to study the immobilization and stabilization of two commercial enzymes: Endocellulase (E-CELBA) in dextran coated iron oxide magnetic nanoparticles activated with aldehyde groups (DIOMNP) and β-glucosidase (E-BGOSPC) in glyoxyl agarose (GLA) so that their immobilized derivatives could be applied in the saccharification of pretreated sugarcane bagasse. This was the first time that the pretreated sugarcane bagasse was saccharified by cascade reaction using a endocellulase immobilized on dextran coated Fe2O3 with aldehyde groups combined with a β-glucosidase immobilized on glyoxyl agarose. Both enzymes were successfully immobilized (more than 60% after reduction with sodium borohydride) and presented higher thermal stability than free enzymes at 60, 70, and 80 °C. The enzymatic hydrolysis of the sugarcane bagasse was carried out with 15 U of each enzyme per gram of bagasse in a solid-liquid ratio of 1:20 for 48 h at 50 °C. Under these conditions, 39.06 ± 1.18% of the cellulose present in the pretreated bagasse was hydrolyzed, producing 14.11 ± 0.47 g/L of reducing sugars (94.54% glucose). In addition, DIOMNP endo-cellulase derivative maintained 61.40 ± 1.17% of its enzymatic activity after seven reuse cycles, and GLA β-glucosidase derivative maintained up to 58.20 ± 1.55% of its enzymatic activity after nine reuse cycles.

Sugarcane bagasse was used as an inexpensive alternative carbon source for production of β-xylanases from Aspergillus terreus. The induction profile showed that the xylanase activity was detected from the 6th day of cultivation period. Two low molecular weight enzymes, named Xyl T1 and Xyl T2 were purified to apparent homogeneity by ultrafiltration, gel filtration and ion exchange chromatographies and presented molecular masses of 24.3and 23.60 kDa, as determined by SDS-PAGE, respectively. Xyl T1 showed highest activity at 50 °C and pH 6.0, while Xyl T2 was most active at 45 °C and pH 5.0. Mass spectrometry analysis of trypsin digested Xyl T1 and Xyl T2 showed two different fingerprinting spectra, indicating that they are distinct enzymes. Both enzymes were specific for xylan as substrate. Xyl T1 was inhibited in greater or lesser degree by phenolic compounds, while Xyl T2 was very resistant to the inhibitory effect of all phenolic compounds tested. The apparent km values of Xyl T2, using birchwood xylan as substrate, decreased in the presence of six phenolic compounds. Both enzymes were inhibited by N-bromosuccinimide and Hg(2+) and activated by Mn(2+). Incubation of Xyl T1 and Xyl T2 with L-cysteine increased their half-lives up to 14 and 24 h at 50 °C, respectively. Atomic force microscopy showed a bimodal size distribution of globular particles for both enzymes, indicating that Xyl T1 is larger than Xyl T2.

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Restaurantes podem propiciar doenças veiculadas por alimentos, assim, medidas de controle devem ser realizadas. Objetivou-se quantificar coliformes totais, termotolerantes e bactérias heterotróficas mesófilas na superfície da bancada da pia de manipulação, e bioaerossóis fúngicos em unidade de alimentação em uma instituição de ensino, antes e durante o processamento dos alimentos, e após higienização do local de trabalho. As amostras foram colhidas por swab e o ar, pela exposição, durante 15 minutos, de placas de PDA acidificado, em diferentes dias da semana totalizando dezesseis coletas. Coliformes totais (35 ºC, 24/48 h) e termotolerantes (45 ºC, 24 h) foram quantificados por inoculação de diluições seriadas, em caldo VB e EC, respectivamente, e os resultados expressos em NMP/cm2. A contagem de mesófilos (35 °C, 48 h) foi realizada em ágar PCA, e os resultados expressos em UFC/cm2. Os fungos anemófilos cultivados a 25 ºC por sete dias foram expressos em UFC/15 min. Os resultados foram analisados em software ASSISTAT 7.6 betas. Foi verificada contagem > 103NMP/cm2 para coliformes totais durante o processamento, e após higienização, decaimento de 16% em relação à média inicial. Redução de 56,3% foi observada para coliformes termotolerantes. O número de mesófilos se mantiveram ≥ 3 ciclos log, independentemente, do período da coleta (antes, durante ou após processamento). 54,2% das amostras do ar apresentaram altas contagens para fungos (> 50 UFC/15 min.). Os resultados indicam a possível geração de riscos e ocorrência de toxinfecções alimentares. Quando bem realizada, a higienização é eficaz na redução da carga microbiana. Sugere-se melhor monitoramento dos procedimentos realizados pelos manipuladores. Palavras-chave: Aerossóis. Coliformes. Mesófilos. AbstractRestaurants can provide food-borne diseases, so control measures must be taken. The objective of this study was to quantify total coliforms, thermotolerant bacteria and mesophilic heterotrophic bacteria on the sink basin surface, and fungal bioaerosols in a feeding unit at a teaching institution, before and during food processing, and after cleaning the workplace. Samples were collected by swab and air by exposure for 15 minutes of acidified PDA plates on different days of the week totaling sixteen samples. Total (35°C, 24/48 h) and thermotolerant coliforms (45 °C, 24 h) were quantified by inoculation of serial dilutions in VB and EC broth, respectively, and the results expressed as MLN/cm2. The counts of mesophiles (35 °C, 48 h) were performed on PCA agar and the results expressed in CFU/cm2. Anemophilous fungi cultured at 25°C for seven days were expressed in CFU/15 min. The results were analyzed in ASSISTAT 7.6 betas software. It was verified a count > 103 MLN/cm2 for total coliforms during the processing, and after sanitization, decay of 16% in relation to the initial average. Reduction of 56.3% was observed for thermotolerant coliforms. The number of mesophiles remained ≥ 3 log cycles, regardless of the collection period (before, during or after processing). 54.2% of the air samples had high counts for fungi (> 50 CFU/15 min). The results indicate the possible generation of risks and occurrence of alimentary toxinfections. When properly performed, hygiene is effective in reducing microbial load. It is suggested better procedures monitoring performed by the handlers. Keywords: Aerosols. Coliforms. Mesophiles.

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