11-Hydroxylation of Protoberberine by the Novel Berberine-Utilizing Aerobic Bacterium Sphingobium sp. Strain BD3100

Protoberberine alkaloids, including berberine, palmatine, and berberrubine, are produced by medicinal plants and are known to have various pharmacological effects. We isolated two berberine-utilizing bacteria, Sphingobium sp. strain BD3100 and Rhodococcus sp. strain BD7100, from soil collected at a natural medicine factory. BD3100 had the unique ability to utilize berberine or palmatine as the sole carbon and energy source. BD3100 produced demethyleneberberine in berberine-supplemented medium. In a resting-cell incubation with berberine, BD3100 produced 11-hydroxyberberine; the structure of 11-hydroxyberberine was determined by detailed analysis of NMR and MS spectroscopic data. α-Naphthoflavone, miconazole, and ketoconazole, which are known inhibitors of cytochrome P450, interfered with BD3100 metabolism of berberine in resting cells. Inhibition by miconazole led to the production of a new compound, 11-hydroxydemethyleneberberine. In a resting-cell incubation with palmatine, BD3100 generated 11-hydroxypalmatine. This work represents the first report of the isolation and characterization of novel berberine-utilizing aerobic bacteria for the production of 11-hydroxylation derivatives of berberine and palmatine.