Identification of β-Glucosidase Activity of URN103L and Its Potential to Convert Ginsenoside Rb1 from .

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 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 NRRLB 30929, whereby it was named 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. 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 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.