Regioselective hydroxylation, reduction, and glycosylation of diphenyl compounds by cultured plant cells of Eucalyptus perriniana

Abstract

Bisphenol A and benzophenone, diphenyl compounds, were regioselectively hydroxylated, reduced, and glycosylated by the cultured plant cells of Eucalyptus perriniana. Three known biotransformation products and two new products, 2-(3-β-D-glucopyranosyloxy-4-hydroxyphenyl)-2-(4-β-D-glucopyranosyloxyphenyl)propane and 2-(3-β-D-glucopyranosyloxy-4-β-D-glucopyranosyloxyphenyl)-2-(4-hydroxyphenyl)propane, were isolated after seven days' incubation of bisphenol A. This shows that the cultured cells of E. perriniana regioselectively hydroxylate at C-6 and C-12 of bisphenol A and that the glycosides can be formed at the hydroxyl group at C-6, 7, 12, and 13. On the other hand, two known products and two new products, 4-O-[6-O-(α-L-rhamnopyranosyl)-β-D-glucopyranosyl]benzophenone and diphenylmethyl 6-O-(β-D-glucopyranosyl)-β-D-glucopyranoside, were obtained from the biotransformation of benzophenone, showing that the cultured cells of E. perriniana regioselectively hydroxylate at C-4 and reduce the carbonyl group of benzophenone and that glycosylation can occur at the hydroxyl group at C-4 and C-7. Thus, both diphenyl compounds were removed from the culture medium and accumulated in cells as glycosides. The biotransformation with E. perriniana would provide a very useful process for the phytoremediation of endocrine disrupting chemicals such as diphenyl compounds. This procedure using enzymatic reactions is simple and environmentally friendly.