title: Evaluation of glucosidases of Aspergillus niger strain comparing with other glucosidases in transformation of ginsenoside Rb1 to ginsenosides Rg3.
abstract: The transformation of ginsenoside Rb1 into a specific minor ginsenoside using Aspergillus niger KCCM 11239, as well as the identification of the transformed products and the pathway via thin layer chromatography and high performance liquid chromatography were evaluated to develop a new biologically active material. The conversion of ginsenoside Rb1 generated Rd, Rg3, Rh2, and compound K although the reaction rates were low due to the low concentration. In enzymatic conversion, all of the ginsenoside Rb1 was converted to ginsenoside Rd and ginsenoside Rg3 after 24 h of incubation. The crude enzyme (β-glucosidase) from A. niger KCCM 11239 hydrolyzed the β-(1→6)-glucosidic linkage at the C-20 of ginsenoside Rb1 to generate ginsenoside Rd and ginsenoside Rg3. Our experimental demonstration showing that A. niger KCCM 11239 produces the ginsenoside-hydrolyzing β-glucosidase reflects the feasibility of developing a specific bioconversion process to obtain active minor ginsenosides.
authors.affiliation: Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul, Korea.
authors.forename: Kyung Hoon
authors.initials: KH
authors.lastname: Chang
authors.affiliation: Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul, Korea.
authors.forename: Mi Na
authors.initials: MN
authors.lastname: Jo
authors.affiliation: Bio/Molecular Informatics Center, Konkuk University, Seoul, Korea.
authors.forename: Kee-Tae
authors.initials: KT
authors.lastname: Kim
authors.affiliation: Department of Food Science and Biotechnology of Animal Resources, Konkuk University, Seoul, Korea ; Bio/Molecular Informatics Center, Konkuk University, Seoul, Korea.
authors.forename: Hyun-Dong
authors.initials: HD
authors.lastname: Paik
keywords: Aspergillus niger; Panax ginseng; ginsenoside Rg3; transformation; β-glucosidase