• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.931-937
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• 2018

Glycosyltransferases (GTs) from microbes are an emerging and rich source for efficient glycol-transformation of natural/unnatural compounds. Here, we probed the catalytic capability and substrate promiscuity of BmmGT1 from marine-derived Bacillus methylotrophicus B-9987. The regioselectivity of BmmGT1 on macrolactin A (1) was explored by optimization of the reaction conditions, in which a series of O-glycosylated macrolactins (1a-1e) were generated, including two new di/tri-O-glucosyl analogs (1b and 1e). Furthermore, BmmGT1 was able to catalyze the glycosylation of the thiol (S-) or amine (N-) sites of phenolic compounds (2 and 3), leading to the generation of N- (2a) or S-glycosides (3a and 3b). The present study demonstrates that BmmGT1 could serve as a potential enzyme tool for O-, N-, or S-glycosyl structural diversification of compounds for drug discovery.

• Journal of Ginseng Research
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• v.20 no.2
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• pp.168-172
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• 1996

Ginsenoside Rb,, at a concentration of 10 $\mu\textrm{g}$/ml and over, initiated the cycle of oscillation of ion flux in erythrocytes after the cells had been treated with a protonophore, carbonyl cyanide p-trifluoro-methoxyphenyl hydrazone (FCCP) and then with a $Ca^{2+}$ ionophore, A23,3,. Its action was similar to the additional portion of $Ca^{2+}$-ionophore or $Ca^{2+}$ ion to the erythrocytes. Effects of $Rg_1$ and Rf were different from that of Rb,. They did not induce the oscillation. They, however, increased the extracellular $K^{+}$ concentration and pH without returning to the initial state in the erythrocytes processed with FCCP and $A_{23187}$. We established that ginsenosides from 20-(5)-panaxatriol family induced the membrane hyperpolarization in erythrocytes, which was attenuated by the pretreatment of $Rb_1$, a major component of 20-(5)-panaxadiol.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.108-113
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• 1986

Ginseng saponin absorbed in rat blood and liver were analyzed by High Performance Liquid Chromatography. The amount of saponin was estimated from peak area of the corresponding fraction and the specific radioactivity was then calculated, The radioactivity of the methanol-water extract of blood serum and livers of ginseng saponin administered rats decreased rapidly during the first four hours after the saponin administration. However, the radioactivity disappearance rate was relatively slow when the radioactivity was below a certain level. It seemed that the glycosides of panax ginseng were absorbed partly in the undissociated form and the saponin level of the liver might be maintained at 10-6% - 10-5% for a considerable period of time in ginseng administered rats.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.317-334
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• 2002

Ginsenosides are metabolized (deglycosylated) by intestinal bacteria to active forms after oral administration. 20(S)-Protopanaxadiol $20-O-{\beta}-D-glucopyranoside$ (M1) and 20(S)-protopanaxatriol (M4) are the main intestinal bacterial metabolites (IBMs) of protopanaxadiol- and protopanaxatriol-type glycosides. M1 was selectively accumulated into the liver soon after its intravenous (i.v.) administration to mice, and mostly excreted as bile; however, some M1 was transformed to fatty acid ester (EMl) in the liver. EM1 was isolated from rats in a recovery dose of approximately $24mol\%.$ Structural analysis indicated that EM1 comprised a family of fatty acid mono-esters of M1. Because EM1 was not excreted as bile as Ml was, it was accumulated in the liver longer than M1. The in vitro cytotoxicity of M1 was attenuated by fatty acid esterification, implying that esterification is a detoxification reaction. However, esterified M1 (EM1) inhibited the growth of B16 melanoma more than Ml in vivo. The in vivo antitumor activity paralleled with the pharmacokinetic behavior. In the case of M4, orally administered M4 was absorbed from the small intestine into the mesenteric lymphatics followed by the rapid esterification of M4 with fatty acids and its spreading to other organs in the body and excretion as bile. The administration of M4 prior to tumor injection abrogated the enhanced lung metastasis in the mice pretreated with 2-chloroadenosine more effectively than in those pretreated with anti-asialo GMl. Both EM1 and EM4 did not directly affect tumor growth in vitro, whereas EM1 promoted tumor cell lysis by lymphocytes, particularly non-adherent splenocytes, and EM4 stimulated splenic NK cells to become cytotoxic to tumor cells. Thus, the esterification of IBM with fatty acids potentiated the antitumor activity of parental IBM through delay of the clearance and through immunostimulation. These results suggest that the fatty acid conjugates of IBMs may be the real active principles of ginsenosides in the body.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.477-479
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• 2018

A Gram-positive, rod-shaped, ivory colored, and motile, Lactobacillus koreensis 26-25 was isolated from Korean kimchi. Strain 26-25 showed the ability of conversion from major ginsenosides into minor ginsenosides for which whole genome was sequenced. The whole genome sequence of Lactobacillus koreensis 26-25 consisted of one circular chromosome comprised of 3,006,812 bp, with a DNA G + C content of 49.23%. The whole genome analysis of strain 26-25 showed many glycosides hydrolase genes, which may contribute to identify the genes responsible for transformation of major ginsenosides into minor ginsenosides for its high pharmacological effects.

• KSBB Journal
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• v.23 no.1
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• pp.44-47
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• 2008

Anthracycline antibiotics doxorubicin (DXR) is clinically important cancer therapeutic agent produced by Streptomyces peucetius. DXR result by further metabolism of rhodomycin D (RHOD) and require a deoxy-sugar component for their biological activity. In this study, production of TDP-L-daunosamine and its attachment to ${\varepsilon}$-rhodomycinone (RHO) to generate RHOD has been achieved by bioconversion in Streptomyces venezuelae that bears eleven genes. S. peucetius seven genes (dnmUTJVZQS) were transformed by plasmid and S. venezuelae two genes desIII, IV and two more S. peucetius drrA, B genes were integrated into chromosomal DNA. To generate the feeding substrate RHO, 6L S. peucetius grown on agar plate was harvested, extracted with organic solvent and then purified using preparative HPLC. Recombinant S. venezuelae grown on agar plate containing RHO was harvested and its n-butanol soluble components were extracted. The glycosylated product of aromatic polyketide RHO using heterologous host S. venezuelae presents the minimal information for TDP-L-daunosamine biosynthesis and its attachment onto aglycone. Moreover, the structure of auxiliary protein, DnrQ, was predicted by fold recognition and homology modeling in this study. This is a general approach to further expand of new glycosides of antitumor anthracycline antibiotics.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.2
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• pp.189-194
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• 2015

Streptococcus mutans (S. mutans) is one of the most important bacteria in the formation of dental plaque and dental caries. S. mutans adheres to an acquired pellicle formed on the tooth surface, and aggregates with many oral bacteria, and initiates plaque formation by synthesizing glucan from sucrose, which is catalyzed by glucosyltransferases. S. mutans metabolizes the dietary sugar to the organic acids. The organic acids demineralize tooth surface and result in dental caries. Galla Chinensis have been traditionally used for stopping bleeding of gingiva, removing edema and halitosis, drainage, fixing the teeth and as an antiphlogistic agent. In previous reports, antibacterial effects of Galla Chinensis have been investigated whereas anti-cariogenic effects is still not examined enough. Therefore we tested effects of ethanol extracts of Galla Chinensis on the cariogenic properties such as the growth, acid production, adhesion, and insoluble glucan synthesis of S. mutans. In the result, ethanol extracts of Galla Chinensis showed the inhibition of S. mutans growth and organic acids production over 0.031 mg/ml concentrations. The adhesion of S. mutans to Saliva-coated Hydroxyapatite beads S-HAs has decreased with the increase of concentration of ethanol extracts of Galla Chinensis. And it seems to have adhesion inhibitory effect in concentration of over 0.25 mg/ml. It gives us the result that Galla Chinensis have anti-caries effects. But ethanol extract of Galla Chinensis didn't have inhibitory effect on insoluble glucan synthesis. Preliminary phytochemical analysis of the ethanol extract of Galla Chinensis showed strong phenolic compounds, medium steroids & terpenoids and glycosides, and weak organic acids and peptides. These results suggest that the ethanol extracts of Galla Chinensis may have anti-cariogenic properties, which may be able to be related with strong phenolic compounds.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1046-1050
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• 2009

Our previous study showed that isoflavone profile of soybean undergoes a significant change during cheonggukjang preparation. In particular, the content of metabolite(s) with similar retention time to glycitein under the high performance liquid chromatography (HPLC) condition was significantly increased while the levels of genistein and its derivatives were notably lowered. Therefore, we hypothesized that genistein and its derivatives might be converted to genistein glucosides with similar elution time to glycitein. Our current data suggest that genistein and its derivatives are extensively metabolized into various compounds including genistein glycosides, but not glycitein or its derivatives, by Bacillus species isolated from traditional cheonggukjang. Some of daidzein was also converted into a derivative with shorter retention time by Bacillus amyloliquefaciens 51 and 86-1 but not by Bacillus subtilis 3-5 and 3-17. As metabolism of soy isoflavones, major health-promoting components in soy products, is widely variable depending upon Bacillus species, it is essential to select microorganism that minimizes the breakdown or modification of soy isoflavones in the process of fermented soy product manufacture.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.163-169
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• 2009

A total of 155 microbial strains were isolated from the Korean traditional soybean paste based on their morphological features on the growth of agar plate. Among the isolated strains, a total of 28 strains were capable of hydrolyzing isoflavone glycoside to isoflavone aglycone efficiently in the soybean paste. Finally, two strains, K123-1 and SI, were selected because of their resistance to 15% NaCl and ability to convert isoflavone glycoside to isoflavone aglycone efficiently during the fermentation of soybean paste. The isolated strains K123-1 and SI were identified to be Pichia guilliermondii and Candida fermentati, respectively, using the partial 26S rDNA sequence analysis and phylogenic analysis. Pichia guilliermondii K123-1 and Candida fermentati SI converted daidzin to daidzein up to 96% and 95%, respectively, and genistin to genistein up to 92% when soybean pastes were fermented at $30^{\circ}C$ for 20 days with a single isolated strain. Pichia guilliermondii K123-1 and Candida fermentati SI were able to grow in the presence of 15% NaCl on both liquid medium and agar plate. We think that Pichia guilliermondii K123-1 and Candida fermentati SI might be one of good candidates for making functional soybean paste because they are isolated from the Korean traditional soybean paste and have a good ability to convert isoflavone glycosides to isoflavone aglycones and a high salt tolerance.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.133-137
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• 2013

Vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), P- and E-selectin play a pivotal role for initiation of atherosclerosis. Ginsenoside, a class of steroid glycosides, is abundant in Panax ginseng root, which has been used for prevention of illness in Korea. In this study, we investigated the mechanism(s) by which ginsenoside Rg2 may inhibit VCAM-1 and ICAM-1 expressions stimulated with lipopolysaccharide (LPS) in human umbilical vein endothelial cell (HUVEC). LPS increased VCAM-1 and ICAM-1 expression. Ginsenoside Rg2 prevented LPS-mediated increase of VCAM-1 and ICAM-1 expression. On the other hand, JSH, a nuclear factor kappa B (NF-${\kappa}B$) inhibitor, reduced both VCAM-1 and ICAM-1 expression stimulated with LPS. SB202190, inhibitor of p38 mitogen-activated protein kinase (p38 MAPK), and wortmannin, phosphatidylinositol 3-kinase (PI3-kinase) inhibitor, reduced LPS-mediated VCAM-1 but not ICAM-1 expression. PD98059, inhibitor of mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (MEK/ERK) did not affect VCAM-1 and ICAM-1 expression stimulated with LPS. SP600125, inhibitor of c-Jun N-terminal kinase (JNK), reduced LPS-mediated ICAM-1 but not VCAM-1 expression. LPS reduced IkappaB${\alpha}$ ($I{\kappa}B{\alpha}$) expression, in a time-dependent manner within 1 hr. Ginsenoside Rg2 prevented the decrease of $I{\kappa}B{\alpha}$ expression stimulated with LPS. Moreover, ginsenoside Rg2 reduced LPS-mediated THP-1 monocyte adhesion to HUVEC, in a concentration-dependent manner. These data provide a novel mechanism where the ginsenoside Rg2 may provide direct vascular benefits with inhibition of leukocyte adhesion into vascular wall thereby providing protection against vascular inflammatory disease.