Biotransformation and resulting biological properties of green tea polyphenols produced by probiotic bacteria

- Eight individual flavonoids were incubated with probiotic bacteria.
- Bifidobacterium animalis B94 survived better best in the glycosylated flavonoid than in catechins.
- Biological activity of 8 flavonoids increased after the incubation with probiotics.
- The most important biological changes were observed in the catechin solutions.

This study evaluates the antioxidant properties and ACE inhibition capacities of eight individual flavonoids before and after incubation with Bifidobacterium animalis ssp. lactis LAFTI@B94®. Changes in flavonoid content and the survival of the probiotics, incubated in individual flavonoid solutions as the only source of carbon, were also determined. The glycosylated flavonoids permitted a higher survival rate of the probiotic bacteria with survival percentages above 50% at 48 h of incubation. The incubation of B. animalis B94 with individual catechins would supposedly produce an increase in all the biological activities tested (ABTS, FRAP and ACE inhibition), but the increments were minor or imperceptible in the flavonol solutions. Epigallocatechin, catechin and epicatechin solutions registered the most important changes in ABTS, FRAP and ACE inhibition capacity, in some cases even doubling their biological activities after incubation with the bacteria. These results are encouraging as the incorporation of B. animalis B94 in various polyphenol-rich foods could be a way of improving the antioxidant properties of the foods. In addition, the polyphenol-rich food could act as a matrix for probiotic strains.