%A Spacova,Irina %A Ahannach,Sarah %A Breynaert,Annelies %A Erreygers,Isabel %A Wittouck,Stijn %A Bron,Peter A. %A Van Beeck,Wannes %A Eilers,Tom %A Alloul,Abbas %A Blansaer,Naïm %A Vlaeminck,Siegfried E. %A Hermans,Nina %A Lebeer,Sarah %D 2022 %J Frontiers in Nutrition %C %F %G English %K Lactobacillus,lactobacilli,Vitamin B2,vitamin-producing bacteria,Fermentation,Dairy alternative,Plant drink,vegan %Q %R 10.3389/fnut.2022.916607 %W %L %M %P %7 %8 2022-June-09 %9 Original Research %# %! Riboflavin-overproducing Limosilactobacillus reuteri %* %< %T Spontaneous Riboflavin-Overproducing Limosilactobacillus reuteri for Biofortification of Fermented Foods %U https://www.frontiersin.org/articles/10.3389/fnut.2022.916607 %V 9 %0 JOURNAL ARTICLE %@ 2296-861X %X Riboflavin-producing lactic acid bacteria represent a promising and cost-effective strategy for food biofortification, but production levels are typically insufficient to support daily human requirements. In this study, we describe the novel human isolate Limosilactobacillus reuteri AMBV339 as a strong food biofortification candidate. This strain shows a high natural riboflavin (vitamin B2) overproduction of 18.36 μg/ml, biomass production up to 6 × 1010 colony-forming units/ml (in the typical range of model lactobacilli), and pH-lowering capacities to a pH as low as 4.03 in common plant-based (coconut, soy, and oat) and cow milk beverages when cultured up to 72 h at 37°C. These properties were especially pronounced in coconut beverage and butter milk fermentations, and were sustained in co-culture with the model starter Streptococcus thermophilus. Furthermore, L. reuteri AMBV339 grown in laboratory media or in a coconut beverage survived in gastric juice and in a simulated gastrointestinal dialysis model with colon phase (GIDM-colon system) inoculated with fecal material from a healthy volunteer. Passive transport of L. reuteri AMBV339-produced riboflavin occurred in the small intestinal and colon stage of the GIDM system, and active transport via intestinal epithelial Caco-2 monolayers was also demonstrated. L. reuteri AMBV339 did not cause fecal microbiome perturbations in the GIDM-colon system and inhibited enteric bacterial pathogens in vitro. Taken together, our data suggests that L. reuteri AMBV339 represents a promising candidate to provide riboflavin fortification of plant-based and dairy foods, and has a high application potential in the human gastrointestinal tract.