RESUMO
Two Saccharomyces cerevisiae strains were tested as the starter yeasts in a traditional cachaça distillery. The strains used were S. cerevisiae UFMG-A829, isolated from a cachaça fermentation process, and S. cerevisiae K1-V1116, obtained from the wine industry. The permanence of each strain in the fermentation must was determined by RAPD (Random Amplified Polymorphic DNA)-PCR, with primer M13. Both yeast strains were prevalent in the vats for approximately 30 days. Indigenous non-Saccharomyces and indigenous S. cerevisiae strains were isolated in lower counts during the fermentation period. Indigenous S. cerevisiae strains were molecularly distinct when compared to the starter yeasts. The two yeasts appeared promising starter yeasts in the fermentation process to produce traditional cachaça.
Duas linhagens de Saccharomyces cerevisiae foram testadas como iniciadoras em uma destilaria de cachaça. Foram utilizadas as linhagens de S. cerevisiae UFMG-A829, isolada de fermentação de cachaça, e S. cerevisiae K1-V1116, de origem vinícola. A permanência de cada linhagem durante a fermentação foi determinada por RAPD (Random Amplified Polymorphic DNA)-PCR, utilizando o iniciador M13. As duas linhagens predominaram nas dornas de fermentação por aproximadamente 30 dias. Leveduras não-Saccharomyces e S. cerevisiae indígenas foram isoladas em menor proporção durante o experimento. As linhagens de S. cerevisiae indígenas apresentaram perfis moleculares distintos em relação às linhagens iniciadoras. As duas linhagens foram promissoras para serem utilizadas como iniciadoras do processo fermentativo para a produção da cachaça.
RESUMO
Black-pigmented gram-negative anaerobes such as Porphyromonas gingivalis and Prevotella intermedia are suspected pathogens in adult periodontitis, whereas Prevotella nigrescens has been associated with health. Antimicrobial resistance among bacteria from this group has been reported in the past decade. This research aimed to evaluate and compare the susceptibility profile of 17 P. intermedia/P. nigrescens isolates recovered from patients with periodontitis and three reference strains to six antimicrobials, prescribed in dentistry in Brazil, and propolis (bee glue). The antimicrobial agents tested were tetracycline, penicillin, clindamycin, erythromycin, metronidazole, meropenem and six ethanolic extracts of propolis (EEPs) from Brazil. The reference strains P. gingivalis ATCC 33277 and P. intermedia ATCC 25611 were used for determination of minimum bactericidal concentration (MBC) and for time-kill assay to the EEPs. All of the strains were susceptible to penicillin, erythromycin, meropenem, metronidazole and 95% of them (n=19) to tetracycline. Thirty six percent (n=7) of the P. intermedia/P. nigrescens strains tested were resistant to clindamycin. As for propolis activity, all strains were susceptible and the minimum inhibitory concentration values ranged from 64 to 256 microg/mL. For the reference strains P. gingivalis ATCC 33277 and Prevotella intermedia ATCC 25611 the MBC was 256 microg/mL and death was observed within 3 h of incubation for P. gingivalis and within 6 h for P. intermedia. The action of propolis (bee glue) against suspected periodontal pathogens suggests that it may be of clinical value.
RESUMO
Diferentes amostras de leishmania foram analisadas quanto à susceptibilidade in vitro ao pentostam - uma cepa de L. (V) braziliensis considerada sensível ao glucantine, três cepas (duas L. (V) braziliensis e uma L. (L) amazonensis) consideradas naturalmente resistentes ao glucantine, uma linhagem resitente (L. (V) guyanensis) selecionada in vitro pela exposiçäo em alta concentraçäo de droga. A elevada sensibilidade destas amostras em contraposiçäo à resistência observada para a glucantine sugere existir relaçäo entre a estrutura química e a atividade destes compostos. Estes dados indicam a necessidade de uma avaliaçäo comparativa de atividade clínica do pentostam e do glucantime no tratamento da leishamniose