2-fucosyllactose (2 FL) is one of the most abundant oligosaccharides in human milk, with benefits on neonatal health. Previous results point to the inability of the fecal microbiota from some infants to ferment 2 FL. We evaluated a probiotic formulation, including the strains Lactobacillus helveticus Rosell®-52 (R0052), Bifidobacterium longum subsp. infantis Rosell®-33 (R0033), and Bifidobacterium bifidum Rosell®-71 (R0071), individually or in an 80:10:10 combination on the microbiota and 2 FL degradation. Independent batch fermentations were performed with feces from six full-term infant donors of two months of age (three breastfed and three formula-fed) with added probiotic formulation or the constituent strains in the presence of 2 FL. Microbiota composition was analyzed by 16S rRNA gene sequencing. Gas accumulation, pH decrease and 2 FL consumption, and levels of different metabolites were determined by chromatography. B. bifidum R0071 was the sole microorganism promoting a partial increase of 2 FL degradation during fermentation in fecal cultures of 2 FL slow-degrading donors. However, major changes in microbiota composition and metabolic activity occurred with L. helveticus R0052 or the probiotic formulation in cultures of slow degraders. Further studies are needed to decipher the role of the host intestinal microbiota in the efficacy of these strains.This research was funded by a contract of Lallemand Health Solutions Inc. with IPLA-CSIC
(Spanish National Research Council contract number 201266) and by the Intramural Spanish National
Research Council project PIE201970E061. S.A. was the recipient of a postdoctoral Juan de la Cierva
contract (Ministry of Science and Innovation, Ref. IJCI-2017-32156), and N.S. has a postdoctoral
contract awarded by the Biosanitary Research Foundation in Asturias (FINBA, Spain)
