Prebiotic effect of agave fructans and mixtures of different degrees of polymerization from Agave angustifolia Haw.

The aim of this work was to investigate the growth rate of six bifidobacteria and four lactobacilli strains when fructans and mixtures with different degrees of polymerization (DP) from A. angustifolia were used as an energy source. We observed that agave fructans stimulated the growth of bifidobacteria and lactobacilli more efficiently that commercial inulins. Bacterial growth, pH drop and SCFA’s production, mainly acetate, were different among strains; while in vitro fermentation revealed that mixtures of different degrees of polymerization and short-DP (< 10) fructans were highly fermented. Biomass and pH drop were larger when the substrate contained mostly short-DP fructans. In conclusion the presence in the mixtures of short-DP fructans, influenced significantly the rate of fermentation by the probiotic bacteria.