Collado M Carmen, Sanz Yolanda
Instituto de Agroquímica y Tecnología de los Alimentos (CSIC), P.O. Box 73, 46100 Burjasot, Valencia, Spain.
J Microbiol Methods. 2006 Sep;66(3):560-3. doi: 10.1016/j.mimet.2006.01.007. Epub 2006 Mar 7.
A method for direct selection of acid-resistant Bifidobacterium strains was developed by prolonged exposure of human feces to homologous lethal stress conditions. The recovered strains were intrinsically resistant to acidic gastric conditions (pH 2.0) and also showed good tolerance to high concentrations of bile salts and NaCl. Bifidobacterium breve and Bifidobacterium adolescentis were, respectively, the infant- and adult-type bifidobacterial species showing the highest ability to develop an acid-tolerant phenotype. Therefore, this procedure could be applicable to the direct selection of Bifidobacterium strains with improved stability in adverse environments and, probably, contribute to expand the spectra of probiotic species of human origin currently marketed.
通过将人类粪便长时间暴露于同源致死应激条件下，开发了一种直接筛选耐酸双歧杆菌菌株的方法。回收的菌株对酸性胃部环境（pH 2.0）具有内在抗性，并且对高浓度胆汁盐和氯化钠也表现出良好的耐受性。短双歧杆菌和青春双歧杆菌分别是婴儿型和成人型双歧杆菌物种，表现出形成耐酸表型的最高能力。因此，该程序可适用于直接筛选在不利环境中具有更高稳定性的双歧杆菌菌株，并可能有助于扩大目前市场上人类来源的益生菌种类范围。
