Problem Solver
Dong-Shan An
Areas Dong-Shan An is Knowledgeable in:
Applied microbiology
Biotransformation of saponins (such as ginseng saponins)
Biotransformation of saponins (such as ginseng saponins)
Techniques Dong-Shan An Uses:
Isolation, identification and taxonomic characteriation of bacteria
Cloning and characterization of bacterial glycosidase hydrolases
Biotransformation of ginsenosides using recombinant glycoside hydrolases
Cloning and characterization of bacterial glycosidase hydrolases
Biotransformation of ginsenosides using recombinant glycoside hydrolases
Dong-Shan An's Problem Solving Skills:
- Development of ginsenoside-hydrolyzing glycoside hydrolases
- Mass production of rare ginsenosides using recombinant enzymes
Dong-Shan An's Problem Solving Experience:
- I have isolated more than 15 novel bacterial strains which convert major ginsenosides into rare ginsenosides from soil of ginseng farms during my Ph. D. course. Then I have isolated, purified and characterized the ginsenoside-hydrolyzing glycoside hydrolases from these isolates and their ginsenoside specificities and ginsenoside-hydrolyzing activities were investigated.
Among them, I have succeeded in cloning of two types of β-D-glucosidases (Bgl3054 and Bgl3082), and two types of α-L-arabinofuranosidases (Araf3054 and Araf3082) from the two bacterial strains, Rhodanobacter sp. Gsoil 3054 and Terrabacter sp. Gsoil3082 , respectively. Using these four recombinant enzymes, I can produce almost every ginsenoside metabolite from the PPD type ginsenosides, such as, gypenoside XVII and gypenoside LXXV from Rb1, C-O and C-Y from Rb2, C-Mx1 and C-Mx from Rb3, C-Mc1 and C-Mc from Rc, F2 and C-K from Rb1, Rb2, Rc and Rd, respectively.