Identification of the antimicrobial substances produced by Solanum palinacanthum (Solanaceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Esterilização de limas endodônticas com plasma de oxigênio

No presente trabalho, analisou-se a eficácia de uma nova técnica de esterilização de instrumental odontológico. Limas endodônticas contaminadas com Escherichia coli, Pseudomonas aeruginosa e Staphylococcus aureus foram esterilizadas em plasma de oxigênio formado através de uma descarga elétrica contínua de 75 mA. Os resultados demonstraram efetiva eliminação dos microrganismos testados, utilizando-se um processo a baixas temperaturas e em tempos menores que os preconizados para processos convencionais (forno de Pasteur e autoclave). Microrganismos gram-negativos foram destruídos em 1 minuto de exposição e gram-positivos em 10 minutos.

Microbiological quality of salmon (Salmo salar) sold in cities of the state of São Paulo, Brazil

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

Design of antiseptic formulations containing extract of Plinia cauliflora

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

Avaliação da atividade anti-séptica de extrato seco de Stryphnodendron adstringens (Mart.) Coville e de preparação cosmética contendo este extrato

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

Avaliação da atividade antibacteriana de folhas de Myrtus communis L. (Myrtaceae)

O óleo essencial e o extrato etanólico obtidos a partir de folhas de Myrtus communis foram avaliados quanto 'a atividade inibitória frente a vários microrganismos. Os halos de inibição de crescimento foram avaliados através das técnicas de template e difusão em disco para as linhagens de Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Bacillus subtilis e Serratia marcescens. Os resultados obtidos evidenciaram que o óleo de M. communis apresentou atividade antibacteriana superior ao extrato etanólico frente a todas as bactérias. A atividade demonstrada tanto para o óleo como para o extrato etanólico frente a algumas linhagens, foi melhor evidenciada pela técnica template. E. coli foi resistente ao óleo e extrato etanólico testados.

Avaliação do potencial alelopático, atividade antimicrobiana e antioxidante dos extratos orgânicos das folhas de Pyrostegia venusta (Ker Gawl.) Miers (Bignoniaceae)

Este trabalho apresenta os resultados de atividade alelopática, antimicrobiana e antioxidante dos extratos orgânicos (hexano, acetato de etila e metanol) das folhas de Pyrostegia venusta (Ker Gawl.) Miers (Bignoniaceae). Para alelopatia, foi estudado o desenvolvimento de Cucumis sativus (pepino), sendo avaliados o comprimento da raiz principal, o número de raízes secundárias e o comprimento do hipocótilo. Os dois primeiros parâmetros foram afetados por todos os três extratos testados enquanto o comprimento do hipocótilo só não foi afetado pelo extrato acetato de etila. Quanto à atividade antimicrobiana, avaliada pelo ensaio de CIM, o extrato hexânico apresentou inibição moderada frente ao Staphylococcus aureus (0,9 mg mL-1) e forte ao Enterococcus hirae (0,5 mg mL-1). O extrato acetato de etila apresentou forte atividade frente Candida albicans (0,3 mg mL-1) enquanto o extrato metanólico não mostrou-se ativo para os microrganismos testados. Por outro lado, o extrato metanólico apresentou a maior capacidade de seqüestrar radicais livres (Concentração Efetiva 50%-CE50 =102,0 ± 56,9 mg mL-1, com TCE50 = 30 min) no ensaio com DPPH (2,2-difenil-1-picril-hidrazila) e o maior teor de compostos fenólicos (116,2 ± 83,0 mg ácido gálico g amostra-1), avaliado pelo ensaio de Folin-Ciocalteau.

Consórcio suíno-peixe: aspectos ambientais e qualidade do pescado

Amostras de músculo de carpa comum (Cyprinus carpio) e de água de três viveiros fertilizados com dejetos de suínos e de um viveiro em que os peixes foram alimentados com ração comercial para peixes foram analisadas durante seis meses. O objetivo foi observar a presença de bactérias patogênicas, como Salmonella, Staphylococcus aureus e coliformes totais e fecais, em peixes comercializados in natura no município de Chapecó, Santa Catarina. Foram aferidos quinzenalmente, na água dos quatro viveiros, oxigênio dissolvido, pH, turbidez, alcalinidade total, dureza total, amônia, nitrato e ortofosfato, bem como a quantidade de coliformes totais e fecais. A análise microbiológica músculo dos peixes demonstrou ausência de Salmonella em todas as amostras. A contagem dos demais microrganismos manteve-se inferior ao limite máximo permitido pela legislação vigente, em todas as amostras. Portanto, os peixes analisados estavam aptos ao consumo humano, pois atenderam aos padrões recomendados pela Divisão Nacional de Vigilância Sanitária de Alimentos (DINAL). A comparação entre os viveiros fertilizados com dejetos de suínos e o viveiro fertilizado com ração comercial para peixes não apresentou diferença significativa, porém apresentou efeito significativo sobre oxigênio dissolvido, turbidez, alcalinidade total e amônia. A matéria orgânica foi responsável pelos maiores valores, com exceção da turbidez, que foi menor no viveiro fertilizado com ração comercial para peixes. Entretanto, após análise de todos os parâmetros físico-químicos e microbiológicos da água dos viveiros, pode-se constatar que todos os viveiros se enquadraram nas classes II ou III da classificação de águas interiores estabelecida pelo CONAMA.

Microbiological quality of recreational waters in Araraquara, SP, Brazil

The microbiological flora of 108 water samples was explored to evaluate the role of recreational waters as a possible source of human diseases in Araraquara, S.P., Brazil. These waters included six swimming pools and three lakes with beaches. The number of total and fecal coliforms, Escherichia coli, fecal streptococci, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, and heterotrophic organisms was determined. As was the occurrence of Salmonella, Shigella, Yersinia, enteropathogenic E. coli (EPEC), enteroinvasive E. coli (EIEC), Mycobacteria, yeasts in general and dermatophytes. Shigella, Yersinia, EIEC and dermatophytes were not isolated. Other organisms or groups of microorganisms were found in variable proportions. From this study it is concluded that recreational waters used by the population of Araraquara, may be contaminated with potentially pathogenic microorganism and this may serve as a source of human diseases.

Fezes de galinhas poedeiras na alimentação de ruminantes análises microbiológicas

The objectives of the present study were: to evaluate the variation in total number of microorganisms in laying hen fecal samples and to identify the pathogenic microorganisms possibly present such as Staphylococcus aureus, Salmonella sp., Clostridium botulinum, C chauvoei, Campylobacter sp., Escherichia coli, and Corynebacterium sp. The experiment was conducted at the School of Agrarian and Veterinarian Sciences of Jaboticabal, - UNESP. Fecal samples were collected from the aviary. A fully randomized experimental design was used with 7 treatments and 4 replications, for a total of 28 samples. A decrease in total number of microorganisms was detected when treatment T0 (zero days of storage) was compared with treatment T6 (42 days of storage), with oscillations in numbers being observed during this period of time. Pathogenic bacteria such as Clostridium noyvi, C perfringens, C sordelli, C septicum and C noyvi type B were detected, as well as non-pathogenic bacteria such as Bacillus sp. and Staphylococcus epidermidis.

Antibiosis associated to Lactobacillus acidophilus growth .1. Strain selection and study of an alternative medium using whey

The production of antimicrobial compounds of some strains of Lactobacillus acidophilus has been studied. They have been grown in whey supplemented with soy milk. It has been found that the production of compounds is able to inhibit the growing of both target bacteria analysed: Staphylococcus aureus and Escherichia coli. The results showed a significant variation (p>0.05) depending on the strain of L. acidophilus and on the level of supplementation utilized. Most of the inhibition observed resulted from the presence of the lactic acid produced. It has also been found the production of other antimicrobial compounds showing inhibitory capacity. The action of these compounds was influenced by the substract pH.

Evaluation of the in vitro activity of cefepime compared to other broad-spectrum cephalosporins against clinical isolates from eighteen Brazilian hospitals by using the Etest

The in vitro activity of cefepime was compared to that of ceftazidime, ceftriaxone, and cefotaxime in a multicenter study involving 10 clinical microbiology laboratories and clinical isolates from 18 Brazilian hospitals from 7 cities (4 states). A total of 982 isolates consecutively collected between December 1995 and March 1996 were susceptibility tested by using Etest and following the NCCLS procedures for agar diffusion tests. The cefepime spectrum was broader than that of the other broad-spectrum cephalosporins against both Gram-negative rods and Gram-positive cocci. Cefepime tons particularly move active against Enterobacter sp. (MIC90, 2 mu g/ml), Serratia sp. (MIC90, 2 mu g/ml) and oxacillin-susceptible Staphylococcus aureus (MIC90, 3 mu g/ml). Against Pseudomonas aeruginosa, cefepime (MIC90 16 mu g/ml) was slightly more active than ceftazidime (MIC90 32 mu g/ml) and 8- to 16-fold more active than ceftriaxone or cefotaxime (MIC90 >256 mu g/ml). Our results show that nosocomial bacteria, especially Gram-negative rods, have a high rate of cephalosporin resistance in Brazil. However, part of these resistant bacteria remains susceptible to cefepime. The Etest was shown to be an excellent method for multicenter studies of the in vitro evaluation of new antimicrobial agents. (C) 1997 Elsevier B.V.

Ação de antibióticos e quimioterápicos sobre alguns agentes baxterianos da mastite bovina, isolados da água utilizada no processo de obtenção do leite

Three strains of Staphylococcus aureus, 73 coagulase negative Staphylococcus and 28 Escherichia coli strains,isolated from water samples from 10 dairy farms, were tested for ''in vitro'' sensitivity to antibiotics and chemotherapeutics. The results showed that all samples isolated presented resistance to at least one active drug tested. The percentage of S. aureus, coagulase negative Staphylococcus and E. coli strains that exhibited resistance to the three active drugs were 100.00%, 84.93% and 71.43%, respectively. These results are important mainly due to the role of water as a vehicle for transmission of mastitis bacterial agents during the milking process.

Microbiological analyses of poultry litter used for ruminant feeding

The aims of this study were to estimate the changes in total bacterial counts (TBC) in poultry litter samples, consisting of rice hulls, after storage, and to identify pathogenic bacteria. For the countings Plate Count agar (Difco) was used. Enrichment and selective media such as blood agar, MacConkey, Baird Parker, brain and heart agar, and egg yolk solid media, and cooked meat and brain and heart infusion, incubated under aerobic or anaerobic conditions were used to isolate Staphylococcus aureus, Salmonella sp, Clostridium perfringens, C. botulinum, C. chauvoei, Campylobacter sp, Escherichia coli, and Corynebacterium sp. Litter samples were collected from the houses of the Veterinary School experimental aviary. A fully randomized experimental design was used with four treatments and four replications, for a total of 16 samples. A decrease in TBC was detected when treatment T1 (zero days of storage) was compared with treatments T2 (14 days of storage). on the other hand the treatments T3 (28 days of storage) and T4 (42 days of storage) presented significantly superior counting in relation to treatment T1. Some pathogenic bacteria of Enterobacteriaceae such as Escherichia coil, Proteus, Arizona, Providencia, Edwardsiella, as well as Staphylococcus aureus, S. epidermidis, different species of genus Clostridium as C. perfringens, C. sordelli, C. chauvoei, C. tetani and C. novyi as well as some strains of Corynebacterium pyogenes were isolated.

Bacteriocin-like substances production by Streptococcus-salivarius against oral bacteria

Samples of tongue and bucal mucosa surfaces were obtained from six healthy subjects with the purpose of isolating S. salivarius. It was verified that 47 out of 48 S. salivarius strains produced bacteriocin-like substances against at least one of the indicator species: Actinomyces viscosus, Rothia dentocariosa, Streptococcus pyogenes, Staphylococcus aureus, Streptococcus mutans and Streptococcus sanguis. The method employed to test for bacteriocin production was that of deferred antagonism. The results showed that there was a high antagonism against R. dentocariosa, S. pyogenes and A. viscosus; extremely low against S. mutans and S. sanguis and no inhibition for S. aureus.