In this study, several nonionic surfactants were tried to improve the enzymatic hydrolysis of ginsenoside Rg3 into Rh2 which was catalyzed at 50 degrees C and pH 5.0 by a crude glucosidase extracted from Fusarium sp. ECU2042. Among the biocompatible nonionic surfactants, polyethylene glycol 350 monomethyl ether was shown to be the best. After optimizing some influencing factors on the reaction, the conversion of Rg3 (5 g/l) with 10 g/l crude enzyme reached almost 100% in the presence of the nonionic surfactant (7.5%, w/v), which was 25% higher than that in buffer without any surfactant. Furthermore, the enzyme stability was affected faintly by the surfactant.
"Ginsenosides are generally recognized as the principle bioactive ingredients in ginseng and reported to have a wide variety of physiological and pharmacological effects . Ginsenoside Rh2 (Figure 1(a)) is a rare ginsenoside that is found only in red ginseng and can be manufactured from other available ginsenosides, which belongs to protopanaxadiol-type ginsenosides the same as ginsenoside Rh2 and just has one more glucose molecule at C-3 position . Ginsenoside Rh2 has anticancer activity that induces apoptotic cell death of some cancer cell lines    and caused G1 phase cell cycle arrest in human breast cancer cells . "
[Show abstract][Hide abstract] ABSTRACT: The present study was carried out to evaluate the inhibitory effects of ginsenoside Rh2 on nuclear-factor- (NF-) κ B in lipopolysaccharide- (LPS-) activated RAW 264.7 murine macrophages. RAW 264.7 cells were pretreated with indicated concentrations of ginsenoside Rh2 for 1 h prior to the incubation of LPS (1 μ g/mL) for indicated time period. Ginsenoside Rh2 reduced CD14 and Toll-like receptor 4 (TLR4) expressions 24 h after LPS stimulation. Furthermore, ginsenoside Rh2 significantly inhibited TGF-beta-activated kinase 1 (TAK1) phosphorylation 30 min after LPS stimulation. Ginsenoside Rh2 was further shown to inhibit NF- κ B p65 translocation into the nucleus by suppressing I κ B- α degradation. Also, LPS increased mRNA expression of TNF- α and IL-1 α time-dependently, while TQ reduced TNF- α within 3 h and IL-1 α within 1 h. And we firstly found that pretreatment of ginsenoside Rh2 successively inhibited hypoxia-inducible factor- (HIF-) 1 α expression increased by LPS. In conclusion, ginsenoside Rh2 may inhibit LPS-induced NF- κ B activation and reduce HIF-1 α accumulation, suggesting that ginsenoside Rh2 may be considered as a potential therapeutic candidate for chronic inflammatory diseases.
Evidence-based Complementary and Alternative Medicine 02/2013; 2013(7):646728. DOI:10.1155/2013/646728 · 1.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Over the past several decades, the pharmacological effects of ginsenosides in Panax ginseng roots have been extensively investigated. Here, we developed a method for producing specific ginsenosides (F1 and F2) with good yields (F1:162 mg/g, F2:305 mg/g) using β-glycosidase purified from Aspergillus niger. In addition, each ginsenoside (at least 25 species) was separated and purified by high performance liquid chromatography (HPLC) using five different types of solvents and different purification steps. In addition, the Rg3:Rh2 mixture (1:1, w/w) was shown to inhibit a specific lung cancer cell line (NCI-H232) in vivo, displaying an anticancer effect at a dose lower than achieved using treatments with single Rg3 or Rh2. This finding suggests that the combination of ginsenosides for targeting anticancer is more effective than the use of a single ginsenoside from ginseng or red ginseng.
[Show abstract][Hide abstract] ABSTRACT: Biocatalysis is widely studied as an alternative to conventional chemical methods in chiral synthesis due to its high selectivity
and the reaction ability under mild conditions. Various types of enzymes with high stereoselectivity have been screened from
nature for the purpose of preparing important chiral synthons. In this chapter, some enzymatic reactions, including enantioselective
bioresolution and asymmetric biotransformation, catalyzed by hydrolases, oxidoreductases and lyases, as well as their applications
to chiral synthesis are overviewed, and some special enzymatic reaction modes, such as enantioconvergent reaction, dynamic
kinetic resolution, and deracemization, are described.
KeywordsAsymmetric biotransformation-Biocatalysts-Chiral synthesis-Kinetic resolution
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