The Heterocyclic Ring Fission and Dehydroxylation of Catechins and Related Compounds by Eubacterium sp. Strain SDG-2, a Human Intestinal Bacterium

A human intestinal bacterium, Eubacterium (E.) sp. strain SDG-2, was tested for its ability to metabolize various (3R)- and (3S)-flavan-3-ols and their 3-O-gallates. This bacterium cleaved the C-ring of (3R)- and (3S)-flavan-3-ols to give 1,3-diphenylpropan-2-ol derivatives, but not their 3-O-gallates. Furthermore, E. sp. strain SDG-2 had the ability of p-dehydroxylation in the B-ring of (3R)-flavan-3-ols, such as (−)-catechin, (−)-epicatechin, (−)-gallocatechin and (−)-epigallocatechin, but not of (3S)-flavan-3-ols, such as (+)-catechin and (+)-epicatechin.