Flavonoid bioconversion in Bifidobacterium pseudocatenulatum B7003: A potential probiotic strain for functional food development

Flavonoids are plant derived compounds mainly present as O-glycosides. They are hydrolyzed by gut microbial enzymes to their aglycons, which represent the bioavailable and bioactive form. In this work the capability of a Bifidobacterium strain (Bifidobacterium pseudocatenulatum B7003) of being used as a probiotic starter culture to obtain fermented legume milks with an increased concentration of flavonoids in their aglycone form was studied. B7003 strain can effectively bioconvert glycosylated flavonoids while fermenting soybean or common bean derived milks. Conversely, a strain used as negative control (Bifidobacterium longum B7254) could grow on the milks but had low activity in flavonoid bioconversion. B7003 strain possesses basic safety properties, the capability of adhering to gut epithelial cells and showed resistance to simulated food processing conditions. Thus, B. pseudocatenulatum B7003 complies well with a new vision of probiotics, which, beside benefits deriving from gut transit, have additional functional properties, such as the high bioavailability of flavonoids in their aglycone form.