Metabolism of bisphenol A by hyper lignin-degrading fungus Phanerochaete sordida YK-624 under non-ligninolytic condition.

Recently, we reported the conversion of bisphenol A (BPA) to 4-(2-(4-hydroxyphenyl)propan-2-yl)benzene-1,2-diol (hydroxy-BPA) by hyper lignin-degrading fungus Phanerochaete sordida YK-624 under non-ligninolytic condition. In the present study, the metabolism of hydroxy-BPA by P. sordida YK-624 was demonstrated under non-ligninolytic condition. Under these conditions, approximately 66% of hydroxy-BPA was degraded after 7 d of incubation. High-resolution electrospray ionization mass spectra and nuclear magnetic resonance analyses of the metabolites isolated from the culture broth indicated that hydroxy-BPA was metabolized to 4-(2-(4-hydroxyphenyl)propan-2-yl)-2-methoxyphenol (methoxy-BPA) and to 4-(2-(3,4-dimethoxyphenyl)propan-2-yl)phenol (dimethoxy-BPA) by sequential methylation events. These metabolites showed reduced estrogenic activity compared to BPA. These results suggested that the hydroxy BPA is methylated to two low toxic-methylation metabolites.