Lactobacillus spp. with in vitro probiotic properties from human faeces and traditional fermented products

VIZOSO PINTO, M. G.; FRANZ, C. M. A. P.; SCHILLINGER, U.; HOLZAPFEL, W. H.

INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY

ELSEVIER SCIENCE BV

Año: 2006 vol. 109 p. 205 - 214

0168-1605

Lactobacillus strains from traditional African fermented milk products, as well as human intestinal isolates were identified and investigated invitro for their technological and functional characteristics as potential new probiotic strains. To test survival under gastrointestinal conditions, firstthe protective effect of milk and the effects of medium composition, lysozyme, pepsin, and pH of the medium on bacterial viability were assessedin vitro using the Plackett–Burman statistical model and the commercially used L. johnsonii LA1 probiotic strain. The use of either an artificialgastric electrolyte solution or MRS did not play a significant role in the viability of the cultures, while lysozyme, acidic conditions (pH 2.5),pepsin and the presence of milk significantly influenced the survival of the strain. Therefore, these parameters were selected as important testvariables in a model stomach passage survival trial. Five strains identified as L. plantarum and two identified as L. johnsonii showed good survivalunder simulated gastrointestinal conditions. These selected strains also showed antimicrobial activity, probably due to production of organic acids.All strains exhibited bile salt hydrolase activity, while only the L. plantarum strains showed β-galactosidase activity.