Intestinal survival and persistence of probiotic Lactobacillus and Bifidobacterium strains administered in triple-strain yoghurt

The aim of the present study was to investigate the intestinal survival and persistence of probiotic strains Lactobacillus F19, Lactobacillus acidophilus NCFB 1748, and Bifidobacterium animalis subsp. lactis Bb-12 consumed in a yoghurt (ABC product), and also their effect on the intestinal microbiota. Based on the results of culture studies and strain-level analysis by randomly amplified polymorphic DNA (RAPD) fingerprinting Lactobacillus F19 and B. animalis subsp. lactis Bb-12 survived well through the human gastrointestinal tract; they were detected in reasonable numbers in the faeces of 100% and 79% of the study subjects, respectively. Ingestion of the probiotic yoghurt increased transiently the numbers of bifidobacteria and lactobacilli. For lactobacilli the increase was due to the detection of the ingested probiotic strains in faeces, while in bifidobacteria the increase was likely caused by the increase of indigenous bifidobacteria since the ingested Bifidobacterium strain did not comprise the predominant part of bifidobacterial population during the intervention. Probiotic strains were infrequently detected in mucosal biopsy samples. The present study indicates that developing probiotic food products with multiple probiotic strains is feasible.