Enzymatic Biotransformation of Ginsenoside Rb1 to Compound K by Recombinant β-Glucosidase from Microbacterium esteraromaticum

Abstract

We cloned and characterized a β-glucosidase (bgp3) gene from Microbacterium esteraromaticum isolated from ginseng field. The bgp3 gene consists of 2,271 bp encoding 756 amino acids which have homology to the glycosyl hydrolase family 3 protein domain. The molecular mass of purified Bgp3 was 80 kDa, as determined by SDS-PAGE. The enzyme (Bgp3) catalyzed the conversion of ginsenoside Rb1 to the more pharmacologically active minor ginsenoside Rd and compound K. The Bgp3 hydrolyzed the outer glucose moiety attached to the C-20 position of ginsenoside Rb1, followed by hydrolysis of the inner glucose moiety attached to the C-3 position. Using 0.1 mg mL(-1) enzyme in 20 mM sodium phosphate buffer at 40 °C and pH 7.0, 1.0 mg mL(-1) ginsenoside Rb1 was transformed into 0.46 mg mL(-1) compound K within 60 min with a corresponding molar conversion yield of 77%. Bgp3 hydrolyzed the ginsenoside Rb1 along the following pathway: Rb1 → Rd → compound K.

Effect of Fermented Red Ginseng Extract Enriched in Ginsenoside Rg3 on the Differentiation and Mineralization of Preosteoblastic MC3T3-E1 Cells

“…coli., encoding 831 amino acids, which have homology to the glycosyl hydrolase family 3. 25 To get the maximum yield of soluble active enzymes, it was incubated with 0.5 mM IPTG at 28°C for 9 h. 7,8 Based on the TLC analysis, the incubated sample of the 5th day was good for bioconversion of crude extract of major ginsenosides to minor ginsenosides (Supplementary Fig. S1; Supplementary Data are available online at www.liebertpub.com/jmf).…”

“…4,5 Bea and his colleagues studied the conversion of ginsenosides in the human gastrointestinal tract by the gut microorganism, 6 but recently, enzymatic biotransformation methods have been introduced for the conversion of major ginsenosides into minor ginsenosides. 7,8 The recombinant b-glucosidase 1 and 3 (Bgp1, Bgp3) from Microbacterium esteraromaticum were used for the bioconversion of the major ginsenosides Rb1, Re, and Rg1 into compound K (CK), Rg2, and Rh1, respectively. 7,8 b-Glucosidase (Bgp) hydrolyzes two molecules of glucose or glucose-substituted molecules by acting on b-1,4 bond of a compound.…”

“…7,8 The recombinant b-glucosidase 1 and 3 (Bgp1, Bgp3) from Microbacterium esteraromaticum were used for the bioconversion of the major ginsenosides Rb1, Re, and Rg1 into compound K (CK), Rg2, and Rh1, respectively. 7,8 b-Glucosidase (Bgp) hydrolyzes two molecules of glucose or glucose-substituted molecules by acting on b-1,4 bond of a compound. 9 As previously reported, b-galactosidase from Aspergillus oryzae and b-D-glucosidase from Bacteroides sp.…”

Identification and Characterization of a Mucilaginibacter sp. Strain QM49 β-Glucosidase and Its Use in the Production of the Pharmaceutically Active Minor Ginsenosides ( S )-Rh 1 and ( S )-Rg 2

“…4A). In addition to these PPT-type ginsenosides, BglQM could also transform the PPD-type ginsenosides Rb 1 The metabolic pathways of ginsenoside hydrolysis by BglQM are similar to those of a ␤-glucosidase (Bgpl) from Microbacterium esteraromaticum (32,57), except that Bgpl directly hydrolyzes Rb 1 to (S)-Rg 3 , whereas BglQM hydrolyzed Rb 1 into (S)-Rg 3 via Rd.…”

“…However, these approaches produce nonspecific stereoisomeric mixtures of rare ginsenosides that have low yields and are very difficult to separate. As an alternative, enzymatic methods have been explored as a way to more specifically convert major ginsenosides into pharmacologically active rare ginsenosides (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)52). Furthermore, methods have been developed to efficiently separate a PPT-type ginsenoside mixture (PPTGM) and a PPD-type ginsenoside mixture (PPDGM) from ginseng extracts (34,35).…”