Biotransformation of the Pentahydroxy Flavone Quercetin by <i>Rhizobium loti</i> and <i>Bradyrhizobium</i> Strains ( <i>Lotus</i> )

Abstract

Lotus rhizobia catabolized quercetin in an arabinose-based medium via a novel form of C-ring cleavage, yielding phloroglucinol and protocatechuic acid. Conservation of the A and B rings of the flavone suggests that a chalcone could be formed as a transient intermediate.