How to More Effectively Obtain Ginsenoside Rg5: Understanding Pathways of Conversion.

Ginsenoside Rg5, a relatively uncommon secondary ginsenoside, exhibits notable pharmacological activity and is commonly hypothesized to originate from the dehydration of Rg3. In this work, we compared different conversion pathways using Rb1, -Rg3 and -Rg3 as the raw material under simple acid catalysis. Interestingly, the results indicate that the conversion follows this reaction activity order Rb1 > -Rg3 > -Rg3, which is contrary to the common understanding of Rg5 obtained from Rg3 by dehydration.

An improved method for the preparation of Ginsenoside Rg5 from ginseng fibrous root powder.

Ginsenoside-Rg5, which is derived from high temperature-processed ginseng, exhibits beneficial health effects. In the present study, ginsenoside-Rg5 was directly and rapidly prepared through the extraction of ginseng fibrous root powder (GFRP) at atmospheric pressure. The results showed that the highest extraction yield (3.

Optimization of the selective preparation of 20(R)-ginsenoside Rg3 catalyzed by d, l-tartaric acid using response surface methodology.

The optimization of the selective preparation of 20(R)-ginsenoside Rg3 converting protopanaxadiol type saponins (PPD saponins) by the commercially available d, l-tartaric acid was carried out using response surface methodology (RSM) based on a three-factor and six-level central composite design. The optimal 20(R)-ginsenoside Rg3 de% was predicted to be 94.52% in the combination of the factors (d, l-tartaric acid concentration 1.

Conversion of protopanaxadiol type saponins to ginsenoside Rg3 by lemon.

The ability of fresh lemon (Citrus limon) to convert protopanaxadiol-type saponins into ginsenoside Rg3 was investigated, and the structures of 20(S)-ginsenoside Rg3 (1) and 20(R)-ginsenoside Rg3 (2) were identified by 1H NMR and 13C NMR spectroscopy. The experiment showed that lemon possesses the strong ability to hydrolyze ginsenosides. When protopanaxadiol-type saponins (16 mg/mL) were hydrolyzed by fresh lemon juice at 80 degrees C for 3 hrs, the conversion ratios of ginsenoside Rb1, Rb2, Rc and Rd were 92.

Microbial conversion of ginsenoside Rb1 to minor ginsenoside F2 and gypenoside XVII by Intrasporangium sp. GS603 isolated from soil.

A new strain, GS603, having beta-glucosidase activity was isolated from soil of a ginseng field, and its ability to convert major ginsenoside Rb(1) to minor ginsenoside or gypenoside was studied. Strain GS603 was identified as an Intrasporangium species by phylogenetic analysis and showed high ginsenoside-converting activity in LB and TSA broth but not in nutrient broth. The culture broth of the strain GS603 could convert ginsenoside Rb(1 )into two metabolites, which were analyzed by TLC and HPLC and shown to be the minor ginsenoside F(2) and gypenoside XVII by NMR.

Conversion of major ginsenoside Rb1 to 20(S)-ginsenoside Rg3 by Microbacterium sp. GS514.

Ginseng saponin, the most important secondary metabolite in ginseng, has various pharmacological activities. Many studies have been directed towards converting major ginsenosides to the more active minor ginsenoside, Rg3. Due to the difficulty in preparing ginsenoside Rg3 enzymatically, the compound has been mainly produced by either acid treatment or heating.

Conversion of major ginsenoside Rb1 to ginsenoside F2 by Caulobacter leidyia.

Ginsenoside Rb1 is the most predominant ginsenoside in Panax species (ginseng) and the hydrolysis of this ginsenoside produces pharmaceutically active compounds. Caulobacter leidyia GP45, one of the isolates having strong beta-glucosidase-producing activity, converted ginsenoside Rb(1) to the active metabolites by 91%. The structures of the resultant metabolites were identified by NMR.