Panose, a new prebiotic candidate.

To investigate the prebiotic potential of two novel candidates, sophorose and panose, with in vitro methods. The growth of single microbial strains was first assessed for both substrates in pure cultures, and panose was further analysed in the simulated colon model with mixed human faecal culture. Quantitative PCR and flow cytometry were used to determine the microbial group and strain densities after the simulated colonic fermentation of panose, and chromatographic methods were utilized to analyse metabolite concentrations. In pure cultures, sophorose and panose were both fermented only by few beneficial strains, and in the colon simulator, panose gave a significant increase in the numbers of Bifidobacterium and Bifidobacterium lactis, concomitantly decreasing Bacteroides group. Butyrate and acetate production was significantly increased together with decreased markers of protein fermentation as a result of panose fermentation. Panose had bifidogenic activities in vitro, and these potential beneficial effects should be further assessed in vitro and in vivo. The current study has provided the first data on pure panose fermentation by the endogenous microbiota and extends our knowledge of the selective fermentation of oligosaccharides by the intestinal microbes.