Abstract

The focus of this study was the cloning, expression, and characterization of recombinant ginsenoside hydrolyzing β-glucosidase from Arthrobacter chlorophenolicus with an ultimate objective to more efficiently bio-transform ginse-nosides. The gene bglAch, consisting of 1,260 bp (419 amino acid residues) was cloned and the recombinant enzyme, over-expressed in Escherichia coli BL21 (DE3), was characterized. The GST-fused BglAch was purified using GST·Bind agarose resin and characterized. Under optimal conditions (pH 6.0 and 37°C) BglAch hydrolyzed the outer glucose and arabino-pyranose moieties of ginsenosides Rb1 and Rb2 at the C20 position of the aglycone into ginsenoside Rd. This was fol-lowed by hydrolysis into F2 of the outer glucose moiety of ginsenoside Rd at the C3 position of the aglycone. Additio-nally, BglAch more slowly transformed Rc to F2 via C-Mc1 (compared to hydrolysis of Rb1 or Rb2). These results in-dicate that the recombinant BglAch could be useful for the production of ginsenoside F2 for use in the pharmaceutical and cosmetic industries.

• Keywords: biotransformation; β-glucosidase; recombinant enzyme; minor ginsenoside; Arthrobacter chlorophenolicus