• Journal of Microbiology and Biotechnology
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• v.18 no.12
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• pp.1932-1937
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• 2008

The R-amidase production by a newly isolated strain of Delftia tsuruhatensis ZJB-05174 was optimized in this paper. Effects of factors such as carbon sources, nitrogen sources, and inducers on amidase production were investigated. The medium composition was optimized using central composite designs and response surface analysis. The optimal medium components for enhanced amidase production were found to be as follows: glucose, 8.23 g/l; yeast extract, 11.59 g/l; 2,2-(R,S)-dimethylcyclopropane carboxamide, 1.76 g/l; NaCl, 1 g/l; ${KH_2}{PO_4}$ 1 g/l; and ${K_2}{HPO_4}$ 1 g/l. A maximum enzyme production of 528.21 U/l was obtained under the optimized conditions, which was 4.7 times higher than that obtained under initial conditions.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.120.2-120.2
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to +64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. (omitted)

• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.242-247
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• 1991

- Since steroid $\Delta^1$-dehydrogenase synthesis has been known to be inducible, the mechanism of the enzyme induction of Arthrobacter simplex IAM 1660 was investigated. Among various steroids tested for inducers, hydrocortisone was the most effective inducer when hydrocortisone was used as a substrate for steroid $\Delta^1$-dehydrogenase. Steroid $\Delta^1$-dehydrogenase synthesis was effectively induced by progesterone, prednisolone and androstenedione, while the enzyme was less induced by cholesterol and not by phytosterols. The results suggest that the presence of 3-keto group and short side chain of steroids are the favorable factors for the induction of the $\Delta^1$-dehydrogenase synthesis. The enzyme was induced at the highest level when hydrocortisone was added at early log phase to the concentration of 0.01% of the culture and the culture was grown for 15 hours.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.11-20
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• 2001

Cancer chemoprevention refer to the use of natural or synthetic substances to prevent the initiational and promtional events that occur during the process of carcinogenesis. The effect of Prunella Herba Vulgaris L. Aqua-acupuncture Solution (PVAS) and Prunella Herba Vulgaris L. Water-extracted Solution (PVWS) on the induction of phase II detoxification enzyme (quinone reductase, Glutathione S-transferase) and inhibition of phase I enzyme (cytochrome P4501A1) and benzo[a]pyrene-DNA adduct formation was examined. PVAS is potent inducers of quinone reductase activity. Glutathione levels were increased with PVAS, in cultured murine hepatoma Hepa1c1c7 cells. In addition glutathione S-transferase levels were increased with PVAS. However, there was 45.2% inhibition in the activity of cytochrome P4501A1 enzyme with the treatment of PVAS, $5{\times}$. At concentration of $1{\times}$ and $3{\times}$ of PVAS, the binding of $[^3H]B[a]P$ metabolites to DNA of NCTC-clone 1469 cell was inhibited by 25.3%, 45.0%, respectively. These results suggest that PVAS has chemopreventive potential by inducing quinone reductase and glutathione S-transferase activities, increasing GSH levels, inhibiting the activity of cytochrome P4501A1 and benzo[a]pyrene-DNA adduct formation.

• Natural Product Sciences
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• v.3 no.2
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• pp.81-88
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• 1997

NAD(P)H:quinone reductase (QR) is one of the protective phase II enzymes against toxicity that accomplishes the capacity of detoxification by modulating the effects of mutagens and carcinogens. The detoxification mechanism is that quinone reductase promotes the 2-electron reduction of quinones to hydroquinones which are less reactive. This study is to search new inducers of quinone reductase from natural products, which can be used as cancer chemopreventive agents. Plant extracts were evaluated by using quinone reductase generating system With Hepa 1c1c7 murine hepatoma cell lines for enzyme inducing properties and crystal violet staining method for the measurement of cytotoxicity provoked. We have tested approximately 106 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from 100% methanol extracts of natural products. The ethyl acetate fractions of Vitex rotundifolia $(fruits,\;2FC:\;12.7\;{\mu}g/ml)$, Cnidium officinale $(aerial\;parts,\;2FC:\;10.5\;{\mu}g/ml)$, Chrysanthemum sinese $(flowers,\;2FC:\;17.4{\mu}g/ml)$ and the hexane fractions of Angelica gigas $(roots,\;2FC:\;13.2\;{\mu}g/ml)$, Smilax china $(roots,\;2FC:\;l1.9\;{\mu}g/ml)$, Sophora flavescens $(roots,\;2FC:\;16.3\;{\mu}g/ml)$ revealed the significant induction of quinone reductase in a murine hepatic Hepa 1c1c7 cell culture system.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.43-47
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• 1986

Among the representative phenolic compounds in relation to lignin derivatives and protein synthesis inhibitors, the most effective inducer for the extracellular polyphenol oxidase (PO) of Lentinus edodes JA01 was gallic acid and ferulic acid for Pleurotus ostreatus. Optimum concentration of these inducers was 2.0 mM and 1.0 mM, respectively. Addition of gallic acid after two days culture had the best effect on production of PO enzyme of L. edodes JA01 and for P. ostreatus, and addition of ferulic acid after three days culture had the best effect. Also, in case of L. edodes JA01, polyphenol oxidase activity was parallel to growth curve, whereas the maximum enzyme activity of P. ostreatus was shown at exponential growth phase and declined thereafter.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.143-147
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• 2005

The non-pathogenic, non-glycopeptide-producing actinomycete Streptomyces coelicolor carries a cluster of seven genes (vanSRJKHAX) that confers inducible, high-level resistance to vancomycin. The van genes are organised into four transcription units, vanRS, vanJ, vanK and vanHAX, and these transcripts are induced by vancomycin in a vanR-dependent manner. vanHAX are orthologuous to genes found in vancomycin resistant enterococci that encode enzymes predicted to reprogramme peptidoglycan biosynthesis such that cell wall precursors terminate in D-Ala-D-Lac, rather than D-Ala-D-Ala. vanR and vanS encode a two-component signal transduction system that mediates transcriptional induction of the seven van genes. vanJ and vanK are novel genes that have no counterpart in previously characterised vancomycin-resistance clusters from pathogens. VanK is essential for vancomycin resistance in S. coelicolor and it is required for adding Gly branch to stem peptides terminating D-Ala-D-Lac. Because VanK can recognise D-Lac-containing precursors but the constitutively expressed femX enzyme, encoded elsewhere on the chromosome, cannot recognize D-Lac-containing precursors as a substrate, vancomycin-induced expression of VanHAX in a vanK mutant is lethal. Further, femX null mutants are viable in the presence of glycopeptide antibiotics but die in their absence. Bioassay using vanJp-neo fusion reporter system also showed that all identified inducers for van genes expression were glycopeptide antibiotics, but teicoplanin, a membrane-anchored glycopeptide, failed to act as an inducer.

• Biomolecules & Therapeutics
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• v.19 no.3
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• pp.320-323
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• 2011

We conducted this study to investigate whether berberine signifi cantly affects MUC5AC mucin gene expression and mucin production induced by epidermal growth factor (EGF), phorbol 12-myristate 13-acetate (PMA) or tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) from human airway epithelial cells. Confl uent NCI-H292 cells were pretreated with varying concentrations of berberine for 30 min and then stimulated with EGF, PMA or TNF-${\alpha}$ for 24 h. MUC5AC mucin gene expression and mucin production were measured by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Berberine was found to inhibit the expression of MUC5AC mucin gene induced by EGF, PMA or TNF-${\alpha}$. Berberine also inhibited the production of MUC5AC mucin protein stimulated by the same inducers. This result suggests that berberine can regulate the expression of mucin gene and production of mucin protein, by directly acting on human airway epithelial cells.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.88-88
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to +64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. Here, we developed luciferase reporter gene assay system to detect SXR-based CYP 3A4 transcriptional activity. We have used CYP3A4-Luc plasmid that contains proximal promoter of human CYP3A4 gene upstream of the luciferase gene. We did transient transfection of 3A4-luciferase gene and SXR. In the HepG2 cells transfected with CYP3A4-Luc, when rifampicin treatment was combined with histone deacetylase inhibitor (HDAC Inhibitor), such as Trichostatin A, Hc-toxin and IN 2001 of the luciferase activity was induced 10-20 fold over control.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.178-178
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this Is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to ＋64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. Here, we developed luciferase reporter gene assay system to detect SXR-based CYP 3A4 transcriptional activity. We have used CYP3A4-Luc plasmid that contains proximal promoter of human CYP3A4 gene upstream of the luciferase gene. We did transient transfection of 3A4-luciferase gene and SXR. In the HepG2 cells transfected with CYP3A4-Luc, when rifampicin treatment was combined with histone deacetylase inhibitor (HDAC Inhibitor), such as Trichostatin A, Hc-toxin and IN 2001 of the luciferase activity was induced 10-20 fold over control.