Martins, Flaviano dos SantosCastro, Ieso de MirandaRosa, Carlos AugustoNicoli, Jacques RobertNeves, Maria José2015-11-242015-11-242008MARTINS, F. dos S. et al. Effect of the trehalose levels on the screening of yeast as probiotic by in vivo and in vitro assays. Brazilian Journal of Microbiology, v. 39, p. 50-55, 2008. Disponível em: <http://www.scielo.br/pdf/bjm/v39n1/a12v39n1.pdf>. Acesso em: 21 out. 20151678-4405http://www.repositorio.ufop.br/handle/123456789/5808Probiotics are viable defined microorganisms (bacteria or yeasts) that exert a beneficial effect on the health of the host when ingested in adequate amounts. Screening for such biotherapeutic agents is commonly performed by in vitro assays simulating gastrointestinal environment to determine the ability to survive in the digestive tract. In the present study, the possibility of extrapolation of data obtained in in vitro assays to in vivo conditions was studied using five Saccharomyces cerevisiae strains isolated from Brazilian Atlantic rain forest. Trehalose contents and survival after exposure to a combination of physiological stresses generally found in the gastrointestinal tract of humans were determined for the five yeasts and compared to the behavior of Saccharomyces boulardii, a well-known probiotic. The results were completed with the colonization capacity of the gastrointestinal tract of gnotobiotic mice by these yeast strains. Some results obtained by in vitro assays are not confirmed by in vivo experiments, indicating that the extrapolation cannot be always done.en-USSaccharomyces boulardiiSaccharomyces cerevisiaeStressEffect of the trehalose levels on the screening of yeast as probiotic by in vivo and in vitro assays.Artigo publicado em periodicoTodo o conteúdo do periódico Brazilian Journal of Microbiology, exceto onde identificado, está sob uma licença Creative Commons que permite copiar, distribuir e transmitir o trabalho em qualquer suporte ou formato desde que sejam citados o autor e o licenciante. Não permite o uso para fins comerciais. Fonte: Brazilian Journal of Microbiology <http://www.scielo.br/scielo.php?script=sci_serial&pid=1517-8382&lng=en&nrm=iso>. Acesso em: 16 ago. 2019.http://dx.doi.org/10.1590/S1517-83822008000100012