Antimicrobial activity of six plant extracts from the Brazilian savanna on periodontal pathogens / Actividad antimicrobiana de seis extractos de plantas de la sabana brasileña en patógenos periodontales

The extracts of plants from Brazilian savanna are currently used in popular medicine. This study evaluated the inhibitory activity of the alcoholic and aqueous extracts from savanna plants on periodontal bacteria. The minimal inhibitory concentrations were evaluated by the agar dilution method, using Wilkins-Chalgren agar. Antimicrobial activity of plants extracts on microbial biofilms was determined in microplates. Psidium cattleianum and Myracrodruon urundeuva extracts demonstrated significant inhibitory activity on all bacterial strains tested; alcoholic and aqueous extracts showed similar results. The extracts from these two species were able to inhibit both planktonic cells and microbial biofilm.

Los extractos de las plantas de la sabana brasileña actualmente se utilizan en la medicina popular. Este estudio evaluó la actividad inhibitoria de los extractos alcohólicos y acuosos de plantas de la sabana en bacterias periodontales. Las concentraciones inhibitorias mínimas fueron evaluados por el método de dilución en agar, utilizando agar Wilkins-Chalgren. La actividad antimicrobiana de los extractos de plantas en las biopelículas microbianas se determinó en microplacas. Los extractos de Psidium cattleianum y Myracrodruon urundeuva demostraron una importante actividad inhibitoria sobre todas las cepas bacterianas probadas, extractos alcohólicos y acuosos mostraron resultados similares. Los extractos de estas dos especies fueron capaces de inhibir las células planctónicas y biofilm microbiano.

Resistance to tetracycline and β-lactams and distribution of resistance markers in enteric microorganisms and pseudomonads isolated from the oral cavity

This study evaluated the occurrence of enteric bacteria and pseudomonads resistant to tetracycline and β-lactams in the oral cavity of patients exhibiting gingivitis (n=89), periodontitis (n=79), periodontally healthy (n=50) and wearing complete dentures (n=41). Microbial identification and presence of resistance markers associated with the production of β-lactamases and tetracycline resistance were performed by using biochemical tests and PCR. Susceptibility tests were carried out in 201 isolates of enteric cocci and rods. Resistance to ampicillin, amoxicillin/clavulanic acid, imipenem, meropenem and tetracycline was detected in 57.4 percent, 34.6 percent, 2.4 percent, 1.9 percent and 36.5 percent of the isolates, respectively. β-lactamase production was observed in 41.2 percent of tested microorganisms, while the most commonly found β-lactamase genetic determinant was gene blaTEM. Tetracycline resistance was disseminated and a wide scope of tet genes were detected in all studied microbial genus.

Ocorrência de Aggregatibacter actinomycetemcomitans no biofilme subgengival de crianças com idade de 6 a 12 anos / Occurrence of Aggregatibacter actinomycetemcomitans in subgengival biofilm of children aged 6-12 years old

O presente estudo avaliou as condições gengivais, sócio-econômicas e a ocorrência de A. actinomycetemcomitans em 233 crianças com idade entre 6 e 1 2 anos, em Araçatuba-São Paulo. Na avaliação clínica periodontal foram utilizados os índices de placa e de sangramento a sondagem. A coleta dos espécimes clínicos de biofilme subgengival foi realizada com cones de papel absorvente, que foram introduzidos no interior dos sulcos gengivais sadios ou inflamados, durante 1 minuto, e transferidos para tubos contendo 3ml de VMGA III e para criotubos com 300µl de água ultrapura. As amostras foram cultivadas em ágar TSBV, em anaerobiose, a 37°C, por 3 dias. A presença desse microrganismo também foi avaliada através de PCR com iniciadores específicos. As condições sócio-econômicas da população estudada foram avaliadas por meio de questionário específico. A maioria das crianças estudadas apresentou gengivite. Verificou-se que a baixa renda familiar e o número de crianças na família estão estatisticamente associados com a gengivite nessas crianças, sendo que a ocorrência de A. actinomycetemcomitans não mostrou correlação com as condições gengivais ou sócio-econômicas da população alvo.

The present study evaluated gingival, socioeconomic conditions and the occurrence of Aggregatibacter actinomycetemcomitans in 233 children from 6 to 12 years-old in Araçatuba-São Paulo. In the periodontal evaluation the plaque index and bleeding on probing index were used. Subgingival biofilm samples were taken through sterile paper points, which were transfered to VMGA III or to criotubes with 300µl of ultrapure water. Microbial isolation was carried out using TSBV agar and the occurrence of A. actinomycetemcomitans was also determined by mean of PCR using specific primer pairs. The socio-economic conditions were evaluated by specific questionaire. The vast majority of studied children exihibited gingivitis and it was statistically correlated low income, family's children number and the gingival status of the patients. The occurence of A. actinomycetemcomitans did not show any correlation between gingival or socio-economic conditions and target population.