Microwave Disinfection of Complete Dentures Contaminated In Vitro with Selected Bacteria

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inhibition of Sodium Hypochlorite Antimicrobial Activity in the Presence of Bovine Serum Albumin

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antibacterial activity of four mouthrinses containing triclosan against salivary Staphylococcus aureus

A Diluição Inibitória Máxima (DIM) de anti-sépticos bucais à base de triclosan contra 28 cepas de Staphylococcus aureus foi avaliada. Diluições de 1/10 a 1/655.360 foram preparadas. As cepas foram inoculadas com inoculador multipontual Steers. A DIM foi a maior diluição do anti-séptico que inibiu crescimento microbiano. Os anti-sépticos apresentaram diferentes DIMs.

PCR detection of staphylococcal enterotoxin genes in Staphylococcus aureus strains isolated from raw and pasteurized milk

Milk is considered a nutritious food because it contains several important nutrients including proteins and vitamins. Conversely, it can be a vehicle for several pathogenic bacteria such as Staphylococcus aureus. This study aimed to analyze the frequency of genes encoding the staphylococcal enterotoxins (SEs) SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI and SEJ in S. aureus strains isolated from raw or pasteurized bovine milk. S. aureus was found in 38 (70.4%) out of 54 raw milk samples at concentrations of up to 8.9 X 10(5) CFU/ml. This microorganism was present in eight samples of pasteurized milk before the expiration date and in 11 samples analyzed on the expiration date. of the 57 strains studied, 68.4% were positive for one or more genes encoding the enterotoxins, and 12 different genotypes were identified. The gene coding for enterotoxin A, sea, was the most frequent ( 16 strains, 41%), followed by sec (8 strains, 20.5%), sed (5 strains, 12.8%). seb (3 strains. 7.7%) and see (2 strains, 5.1%). Among the genes encoding the other enterotoxins, seg was the most frequently observed (11 strains. 28.2%), followed by sei (10 strains) and seh and sej (3 strains each). With the recent identification of new SEs, the perceived frequency of enterotoxigenic strains has increased. suggesting that the pathogenic potential of staphylococci may be higher than previously thoughts however, further studies are required to assess the expression of these new SEs by S. aureus. and their impact in foodborne disease. The quality of Brazilian milk is still low. and efforts from the government and the entire productive chain are required to attain consumer safety. (C) 2008 Elsevier B.V. All rights reserved.

Sinergismo entre óleos essenciais e drogas antimicrobianas sobre linhagens de Staphylococcus aureus e Escherichia coli isoladas de casos clínicos humanos

Estudos com plantas e utilização em terapias combinatórias têm sido estimulados. Verificou-se as possíveis interações entre óleos essenciais de plantas [canela (Cinnamomum zeylanicum Blume Lauraceae), capim-cidreira (Cymbopogon citratus (DC.) Stapf, Poaceae), hortelã-pimenta (Mentha piperita L. Lamiaceae), gengibre (Zingiber officinale Roscoe Zingiberaceae), cravo-da-índia (Caryophillus aromaticus L. Myrtaceae) e alecrim (Rosmarinus officinalis L. Lamiaceae)] combinados a oito drogas antimicrobianas frente a doze linhagens de Staphylococcus aureus e doze de Escherichia coli isoladas de humanos. Após determinação da Concentração Inibitória Mínima (CIM) para os óleos pelo método da diluição foram realizados ensaios para verificação de sinergismo entre os óleos essenciais e os antimicrobianos pela metodologia de Kirby & Bauer. S. aureus foi mais suscetível às interações óleos e drogas, tendo o óleo de capim cidreira apresentado sinergismo com as oito drogas testadas, seguido pelo óleo de hortelã com sete drogas. Nos ensaios com E. coli, houve sinergismo apenas para os óleos de alecrim (três drogas) e capim-cidreira (duas drogas). Não ocorreram casos de antagonismo e os resultados de sinergismo foram influenciados pelos microrganismos estudados.

Reproductive biology of the rock shrimp Sicyonia dorsalis (Decapoda: Penaeoidea) from the southeastern coast of Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Optimization of cyclodextrin glucanotransferase production from Bacillus clausii E16 in submerged fermentation using response surface methodology

Cyclodextrin glucanotransferase production from Bacillus clausii E16, a new bacteria isolated from Brazilian soil samples was optimized in shake-flask cultures. A 2 4 full-factorial central composite design was performed to optimize the culture conditions, using a response surface methodology the combined effect among the soluble starch concentration, the peptone concentration, the yeast extract concentration, and the initial pH value of the culture medium was investigated. The optimum concentrations of the components, determined by a 2(4) full-factorial central composite design, were 13.4 g/L soluble starch, 4.9 g/L peptone, 5.9 g/L yeast extract, and initial pH 10.1. Under these optimized conditions, the maximum cyclodextrin glucanotransferase activity was 5.9 U/mL after a 48-h fermentation. This yield was 68% higher than that obtained when the microorganism was cultivated in basal culture medium.

Yacon (Polymnia sanchifolia) extract as a substrate to produce inulinase by Kluyveromyces marxianus var. bulgaricus

The inulinase production by yeast K marxianus var. bulgaricus growing in yacon extract was investigated. The microorganism showed good development in yacon, higher enzymatic activities were achieved at 30% and 40% (v/v) of extract. The cultivation temperature (20, 25, 30, 35, 40 degreesC) neither influenced the growth or the enzymatic activity. The optimum cultivation pH was 3.5. The highest activity was observed at 60 degreesC and pH 4.0. At temperature of 55 C and 60 C occurred sharp decrease in the enzyme activity. (C) 2004 Elsevier Ltd. All rights reserved.

Electrolytic treatment applied to the industrial effluent containing persistent wastes monitored by Bartha respirometric assays

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Keratinolytic activity of Streptomyces sp isolated of poultry processing plant

The keratin is not degraded by common enzyme, keratinases have the ability to degrade native keratin and others insoluble enzymes. In the present work was Studied keratinase produced by Streptomyces sp LMI-1 isolated from industrial plant of poultry processing. The enzyme degraded 87% of feathers after 120 h, it was stimulated by Ba(2+) and inhibited by Ca(2+), Mn(2+), EDTA and Hg(+). The optimum pH and temperature for the enzyme was 8.5 and 60 degrees C, respectively. The enzyme was stable after 2 hours at 50 degrees C. The culture broth analysis by thin layer chromatography showed presence of amino acids serine, methionine, proline, tyrosine and leucine after 72 hours of incubation. The microorganism showed potential for use in industrial process because of higher enzyme production and feathers degradation.

BTEX biodegradation by bacteria from effluents of petroleum refinery

Groundwater contamination with benzene, toluene, ethylbenzene and xylene (BTEX) has been increasing, thus requiring an urgent development of methodologies that are able to remove or minimize the damages these compounds can cause to the environment. The biodegradation process using microorganisms has been regarded as an efficient technology to treat places contaminated with hydrocarbons, since they are able to biotransform and/or biodegrade target pollutants. To prove the efficiency of this process, besides chemical analysis, the use of biological assessments has been indicated. This work identified and selected BTEX-biodegrading microorganisms present in effluents from petroleum refinery, and evaluated the efficiency of microorganism biodegradation process for reducing genotoxic and mutagenic BTEX damage through two test-systems: Allium cepa and hepatoma tissue culture (HTC) cells. Five different non-biodegraded BTEX concentrations were evaluated in relation to biodegraded concentrations. The biodegradation process was performed in a BOO Trak Apparatus (HACH) for 20 days, using microorganisms pre-selected through enrichment. Although the biodegradation usually occurs by a consortium of different microorganisms, the consortium in this study was composed exclusively of five bacteria species and the bacteria Pseudomonas putida was held responsible for the BTEX biodegradation. The chemical analyses showed that BTEX was reduced in the biodegraded concentrations. The results obtained with genotoxicity assays, carried out with both A. cepa and HTC cells, showed that the biodegradation process was able to decrease the genotoxic damages of BTEX. By mutagenic tests, we observed a decrease in damage only to the A. cepa organism. Although no decrease in mutagenicity was observed for HTC cells, no increase of this effect after the biodegradation process was observed either. The application of pre-selected bacteria in biodegradation processes can represent a reliable and effective tool in the treatment of water contaminated with BTEX mixture. Therefore, the raw petroleum refinery effluent might be a source of hydrocarbon-biodegrading microorganisms. (c) 2010 Elsevier B.A. All rights reserved.

Effects of the electrolytic treatment on Bacillus subtilis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Use of sugarcane bagasse and grass hydrolysates as carbon sources for xylanase production by Bacillus circulans D1 in submerged fermentation

The use of sugarcane bagasse and grass as low cost raw material for xylanase production by Bacillus circulans D1 in submerged fermentation was investigated. The microorganism was cultivated in a mineral medium containing hydrolysate of bagasse or grass as carbon source. High production of enzyme was obtained during growth in media with bagasse hydrolysates (8.4 U/mL) and in media with grass hydrolysates (7.5 U/mL). Xylanase production in media with hydrolysates was very close to that obtained in xylan containing media (7.0 U/ mL) and this fact confirm the feasibility of using this agro-industrial byproducts by B. circulans D1 as an alternative to save costs on the enzyme production process. (c) 2005 Elsevier Ltd. All rights reserved.

Enzimas termoestáveis: fontes, produção e aplicação industrial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

ABO blood groups and Helicobacter pylori cagA infection: evidence of an association

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)