Identification of β-Glucosidase Activity of E nterococcus Faecalis CRNB-A3 in Airag and Its Potential to Convert Ginsenoside Rb1 from Panax Ginseng

Concomitant Administration of Red Ginseng Extract with Lactic Acid Bacteria Increases the Plasma Concentration of Deglycosylated Ginsenosides in Healthy Human Subjects

With the increased frequency of red ginseng extract (RGE) and lactic acid bacteria (LAB) co-administration, we aimed to investigate the interactions between RGE and LAB with regard to in vitro and in vivo deglycosylation metabolism and the pharmacokinetics of ginsenosides. As a proof-of-concept study, five healthy humans were administered RGE (104.1 mg of total ginsenosides/day) with or without co-administration of LAB (2 g, 1 billion CFU/day) for 2 weeks, and the plasma concentrations of ginsenosides in human plasma were monitored. The plasma exposure to compound K (CK), ginsenoside Rh2 (GRh2), protopanaxadiol (PPD), and protopanaxatriol (PPT) in the concomitant administration RGE and LAB groups increased by 2.7-, 2.1-, 1.6-, and 3.5-fold, respectively, compared to those in the RGE administration group, without a significant change in T_max. The plasma concentrations of GRb1, GRb2, and GRc remained unchanged, whereas the AUC values of GRd and GRg3 significantly decreased in the concomitant administration RGE and LAB groups. To understand the underlying mechanism, the in vitro metabolic activity of ginsenosides was measured during the fermentation of RGE or individual ginsenosides in the presence of LAB for 1 week. Consistent with the in vivo results, co-incubation with RGE and LAB significantly increased the formation rate of GRh2, CK, PPD, and PPT. These results may be attributed to the facilitated deglycosylation of GRd and GRg3 and the increased production of GRh2, CK, PPD, and PPT by the co-administration of LAB and RGE. In conclusion, LAB supplementation increased the plasma concentrations of deglycosylated ginsenosides, such as GRh2, CK, PPD, and PPT, through facilitated deglycosylation metabolism of ginsenosides in the intestine.

Identification of β-Glucosidase Activity of Lentilactobacillus buchneri URN103L and Its Potential to Convert Ginsenoside Rb1 from Panax ginseng

Lentilactobacillus buchneri isolated from Korean fermented plant foods produces β-glucosidase, which can hydrolyze ginsenoside Rb1 from Panax ginseng to yield ginsenoside Rd. The aim of this study was to determine the mechanisms underlying the extracellular β-glucosidase activity obtained from Lentilactobacillus buchneri URN103L. Among the 17 types of lactic acid bacteria showing positive β-glucosidase activity in the esculin iron agar test, only URN103L was found to exhibit high hydrolytic activity on ginsenoside Rb1. The strain showed 99% homology with Lentilactobacillus buchneri NRRLB 30929, whereby it was named Lentilactobacillus buchneri URN103L. Supernatants of selected cultures with β-glucosidase activity were examined for hydrolysis of the major ginsenoside Rb1 at 40 °C, pH 5.0. Furthermore, the β-glucosidase activity of this strain showed a distinct ability to hydrolyze major ginsenoside Rb1 into minor ginsenosides Rd and Rg3. Lentilactobacillus buchneri URN103L showed higher leucine arylamidase, valine arylamidase, α-galactosidass, β–galactosidase, and β-glucosidase activities than any other strain. We conclude that β-glucosidase from Lentilactobacillus buchneri URN103L can effectively hydrolyze ginsenoside Rb1 into Rd and Rg3. The converted ginsenoside can be used in functional foods, yogurts, beverage products, cosmetics, and other health products.

Effect of Lactic Acid Bacteria on the Pharmacokinetics and Metabolism of Ginsenosides in Mice

This study aims to investigate the effect of lactic acid bacteria (LAB) on in vitro and in vivo metabolism and the pharmacokinetics of ginsenosides in mice. When the in vitro fermentation test of RGE with LAB was carried out, protopanaxadiol (PPD) and protopanaxadiol (PPD), which are final metabolites of ginsenosides but not contained in RGE, were greatly increased. Compound K (CK), ginsenoside Rh1 (GRh1), and GRg3 also increased by about 30%. Other ginsenosides with a sugar number of more than 2 showed a gradual decrease by fermentation with LAB for 7 days, suggesting the involvement of LAB in the deglycosylation of ginsenosides. Incubation of single ginsenoside with LAB produced GRg3, CK, and PPD with the highest formation rate and GRd, GRh2, and GF with the lower rate among PPD-type ginsenosides. Among PPT-type ginsenosides, GRh1 and PPT had the highest formation rate. The amoxicillin pretreatment (20 mg/kg/day, twice a day for 3 days) resulted in a significant decrease in the fecal recovery of CK, PPD, and PPT through the blockade of deglycosylation of ginsenosides after single oral administrations of RGE (2 g/kg) in mice. The plasma concentrations of CK, PPD, and PPT were not detectable without change in GRb1, GRb2, and GRc in this group. LAB supplementation (1 billion CFU/2 g/kg/day for 1 week) after the amoxicillin treatment in mice restored the ginsenoside metabolism and the plasma concentrations of ginsenosides to the control level. In conclusion, the alterations in the gut microbiota environment could change the ginsenoside metabolism and plasma concentrations of ginsenosides. Therefore, the supplementation of LAB with oral administrations of RGE would help increase plasma concentrations of deglycosylated ginsenosides such as CK, PPD, and PPT.

Biotransformation of Major Ginsenoside Rb1 to Rd by Dekkera anomala YAE-1 from Mongolian Fermented Milk (Airag)

Dekkera anomala YAE-1 strain separated from "airag" (Mongolian fermented mare's milk) produces β-glucosidase, which can convert ginsenoside Rb₁ from Panax ginseng. Ginseng-derived bioactive components such as ginsenoside Rb₁ have various immunological and anticancer activities. Airag was collected from five different mare milk farms located near Ulaanbaatar, Mongolia. YAE-1 strains were isolated from airag to examine the hydrolytic activities of β-glucosidase on Korean Panax ginseng using an API ZYM kit. Supernatants of selected cultures having β-glucosidase activity were examined for hydrolysis of the major ginsenoside Rb₁ at 40°C, pH 5.0. The YAE-1 strain was found to be nearly identical at 99.9% homology with Dekkera anomala DB-7B, and was thus named Dekkera anomala YAE-1. This strain exerted higher β-glucosidase activity than other enzymes. Reaction mixtures from Dekkera anomala YAE-1 showed great capacity for converting ginsenoside Rb₁ to ginsenoside Rd. The β-glucosidase produced by Dekkera anomala YAE-1 was able to hydrolyze ginsenoside Rb₁ and convert it to Rd during fermentation of the ginseng. The amount of ginsenoside Rd was highly increased from 0 to 1.404 mg/ml in fermented 20% ginseng root at 7 days.