Isolation and characterization of a human intestinal bacterium Eggerthella sp. CAT-1 capable of cleaving the C-Ring of (+)-catechin and (-)-Epicatechin, followed by p-dehydroxylation of the B-ring

Abstract

We isolated a human intestinal bacterium, capable of cleaving the C-ring and dehydroxylating the Bring of both (+)-catechin (2 R ,3S ) and (-)-epicatechin (2 R ,3R). Although the strain was classified as Eggerthella (Eg.) lenta [named Eg. sp. CAT-1 (JF798636)] by 16S ribosomal RNA (rRNA) gene similarity, it was quite different in substrate specificity from a previously isolated strain, Eg. sp. SDG-2, which takes part in cleavage of the C-ring and dehydroxylation of the 3,4-dihydroxyphenyl moiety (B-ring) of (3R)-flavan-3-ol derivatives. On the other hand, both Eg. sp. CAT-1 and Eg. sp. SDG-2 showed the same substrate specificity against dehydroxylation of enantiomeric lignans, (+)- and (-)-dihydroxyenterodiol, and (+)- and (-)-dihydroxyenterolactone. © 2012 The Pharmaceutical Society of Japan.