Influence of a combination of two potential probiotic strains, Lactobacillus rhamnosus IMC 501® and Lactobacillus paracasei IMC 502® on bowel habits of healthy adults

Aims: This study aims to investigate the effect of different kinds of food products enriched with a combination of two potential probiotic strains, Lactobacillus rhamnosus IMC 501 (R) and Lactobacillus paracasei IMC 502 (R), on bowel habits of healthy adults. Methods and Results: Fifty healthy volunteers took part in a double-blind placebo probiotic feeding study (25 fed probiotics, 25 fed placebo) for 12 weeks. Each volunteer ingested daily one or more food products enriched with a combination of the two potential probiotic strains (probiotic group) or the same food products without the probiotics (control group). Faecal samples were collected before, at the end and 2 weeks later the intervention period, and some of the main groups of faecal bacteria were enumerated by plate count and real-time PCR. Questionnaires on bowel habits were submitted to volunteers. After the intervention, a significant increase in faecal lactobacilli and bifidobacteria were observed in the probiotic group, and stool frequency and stool volume were higher in the probiotic group than in the placebo group. Conclusions: Daily consumption of food products enriched with the two potential probiotic strains, Lact. rhamnosus IMC 501 (R) and Lact. paracasei IMC 502 (R), contributes to improve intestinal microbiota with beneficial properties and enhances bowel habits of healthy adults. Significance and Impact of the Study: The study revealed that Lact. rhamnosus IMC 501 (R) and Lact. paracasei IMC 502 (R) exert a positive effect, in terms of improved bowel habits, on healthy adults.