Development of a non-target metabolomics-based screening method for elucidating metabolic and probiotic potential of bifidobacteria.

Traditional in vitro screening assays for identifying probiotics often fail to provide a metabolomic overview of candidate strains. Thus, this work aimed to develop a non-target metabolomics-based method for screening bifidobacteria from a broad perspective. First, methods for extracting intracellular metabolites of bifidobacteria were compared. Methanol extraction with bead mill and sonication was selected as it yielded the highest metabolome signal intensity and coverage. Multivariate analyses revealed obvious differences in the intracellular metabolome between species/strains. Fourteen differential metabolites that have previously been reported to possess probiotic function were identified. Bifidobacterium animalis subsp. lactis Probio-M8 (M8) had significantly more intracellular lactose than other species/strains but showed lower cell density and viable counts in stationary phase. Adding lactose in the culture medium significantly enhanced the growth of M8 strain but not other tested bifidobacteria. This work provided a new screening method and practical data for selecting potential candidates for further validation. [Display omitted] • A non-targeted metabolomic method was first used for screening of bifidobacteria. • Intracellular metabolomes of bifidobacteria are species−/strain-specific. • Differential metabolomes hint at potentially unidentical probiotic function. • Strain-level optimization is required for enhancing growth of bifidobacterial. [ABSTRACT FROM AUTHOR]