• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.425-432
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• 1998

The strain producing L-lactic acid from starch was isolated from kimchi. The isolated strain was identified as a homofermentative Streptococcus sp. through its morphological, cultural, biochemical characteristics, and named Streptococcus sp. JEJ-6. Lactic acids are of two types, one L-specific and the other D-specific form in a stereospecific form. Streptococcus sp. JEJ-6 produced selectively L-lactic acid from all of the tested carbon sources. The optimum conditions for the L-lactic acid production from the isolated microorganism were determined. For the maximum yield of L-lactic acid from Streptococcus sp. JEJ-6, the cell should be harvested at the early stationary phase, and the growth temperature, pH, and NaCl concentration should be 37$^{\circ}C$, pH 7.0 and 0.1%, respectively. 4% Soluble starch as substrate and organic nitrogen sources such as peptone and yeast extract should be used for the best yield. The optimum pH of the nicotinamide adenine dinucleotide(NAD)-dependent and NAD-independent lactate dehydrogenase(LDH) activities was pH 8.5 and pH 7.0, respectively.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.467-470
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• 2004

We have investigated the key parameters affecting ATP regeneration in a cell-free protein synthesis system derived from Escherichia coli. When glucose-6-phosphate was used as an energy source, the efficiency of ATP regeneration sharply responded to pH change of reaction mixture. In addition, both productivity and reproducibility of protein synthesis was substantially enhanced by introducing appropriate amount of NAD into the reaction mixture. As a result, through the activation of glycolytic pathway under an optimal pH, the batch cell-free system produced over $300\;{\mu}g$ of protein in a 1 mL reaction.

• Journal of Life Science
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• v.19 no.7
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• pp.852-858
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• 2009

The homeostasis of the pyridine nucleotide pool [NAD(P)H and NAD(P)$^+$] is maintained in Rhodobacter sphaeroides mutant strains defective in the cytochrome bci complex or the cytochrome c oxidases in terms of its concentration and redox state. Aerobic derepression of the puf operon, which is under the control of the PrrBA two-component system, in the CBB3 mutant strain of R. sphaeroides was shown to be not the result of changes in the redox state of the pyridine nucleotides and the ubiquinone/ubiquinol pool. Using the bc$_1$ complex knock-out mutant strain of R. sphaeroides, we clearly demonstrated that the inhibitory effect of cbb$_3$, oxidase on spectral complex formation is not caused indirectly by the redox change of the ubiquinone/ubiquinol pool.

• Natural Product Sciences
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• v.7 no.2
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• pp.38-44
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• 2001

NAD(P)H:quinone reductase (QR), known as DT-diaphorase, is a kind of detoxifying phase II metabolic enzyme catalyzing hydroquinone formation by two electron reduction pathway from quinone type compounds, and thus facilitating excretion of quinoids from human body. With the usefulness of QR induction activity assay system for the modulation of toxicants, in the course of searching for cancer chemopreventive agents from natural products, the methanolic extracts of approximately two hundreds of oriental medicines were primarily evaluated using the induction potential of quinone reductase (QR) activity in cultured murine Hepa1c1c7 cells. As a result, several extracts including Hordeum vulgare, Momordica cochinchinensis, Strychnos ignatii, Houttuynia cordata, and Polygala japonica were found to significantly induce QR activity. In addition, the methylene chloride fraction of H. vulgare, one major dietary food source, showed potent induction of QR activity $(CD=6.4{\mu}g/ml)$. Further study for isolation of active principles from these lead extracts is warranted for the discovery of novel cancer chemopreventive agents.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1452-1456
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• 2016

Overexpression of the genes encoding phosphoeneolpyruvate carboxykinase (pckA) and NAD-dependent malic enzyme (maeA) facilitates higher intracellular ATP and NAD(P)H concentrations, respectively, under aerobic conditions in Escherichia coli. To verify a hypothesis that higher intracellular energy reserves might contribute to H₂ fermentation, wild-type E. coli strains overexpressing pckA and maeA were cultured under anaerobic conditions in a glucose minimal medium. Overexpression of pckA and maeA enabled E. coli to produce 3-times and 4-times greater H₂ (193 and 284 nmol, respectively) than the wild type (66 nmol H₂). The pckA and maeA genes were further overexpressed in a hydrogenase-3-enhanced E. coli strain. The hydrogenase-3-enhanced strain (W3110+fhlA) produced 322 nmol H₂, whereas the ATP-enhanced strain (W3110+fhlA+pckA) produced 50% increased H₂ (443 nmol). Total H₂ in the NAD(P)H-enhanced strain (W3110+fhlA+maeA) was similar to that in the control strain at 319 nmol H₂. Possible explanations for the contribution of the increased cellular energy reserves to the enhanced hydrogen fermentation observed are discussed based on the viewpoint of metabolic engineering strategy.

• IMMUNE NETWORK
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• v.9 no.2
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• pp.64-73
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• 2009

Background: 15d-$PGJ_2$ has been known to act as an anti-inflammatory agent and has anti-hypertensive effects. As a result of these properties, we examined the effect of 15d-$PGJ_2$ on the LPS-induced IL-8/CXCL8 mRNA expression in VSMCs from SHR. Methods: Effect and action mechanism of 15d-$PGJ_2$ on the expression of LPS-induced IL-8/CXCL8 mRNA in VSMCs from SHR and WKY were examined by using real-time polymerase chain reaction, electrophoretic mobility shift assay for NF-${\kappa}B$ avtivity, Western blotting analysis for ERK and p38 phosphorylation and flow cytometry for NAD(P)H oxidase activity. Results: 15d-$PGJ_2$ decreased the expression of LPS-induced IL-8/CXCL8 mRNA in WKY VSMCs, but increased the expression of LPS-induced IL-8/CXCL8 mRNA in SHR VSMCs. The upregulatory effect of 15d-$PGJ_2$ in SHR VSMCs was mediated through PPAR${\gamma}$, and dependent on NF-${\kappa}B$ activation and ERK phosphorylation. However, inhibition of the p38 signaling pathway augmented the upregulatory effect of 15d-$PGJ_2$ on LPS-induced IL-8/CXCL8 mRNA. A NAD(P)H oxidase inhibitor inhibited the upregulatory effect of 15d-$PGJ_2$ on LPS-induced IL-8/CXCL8 mRNA expression in SHR VSMCs, and an increase in NAD(P)H oxidase activity was detected in SHR VSMCs treated with 15d-$PGJ_2$/LPS. Conclusion: Our results indicate that the upregulatory effect of 15d-$PGJ_2$ on LPS-induced IL-8/CXCL8 expression in SHR VSMCs is mediated through the PPAR${\gamma}$ and ERK pathway, and may be related to NAD(P)H oxidase activity. However, p38 inactivation may also play an important role in 15d-$PGJ_2$/LPS-induced IL-8/CXCL8 expression in SHR VSMCs.

• Korean Journal of Veterinary Research
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• v.56 no.1
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• pp.15-21
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• 2016

NAD(P)H-quinone oxidoreductase-1 (NQO1) is a down-stream target gene of nuclear factor erythroid 2-related factor 2 (Nrf2), and performs diverse biological functions. Recently, NQO1 is recognized as an effective gene for the cytotoxic inserts with its diverse biological functions, which is focused on antioxidant properties. The aim of present study was to assess the impact of NQO1 knockdown on cytoprotection-related protein expression in cisplatin cytotoxicity by using small interfering (si) RNA targeted on NQO1 gene. Cytotoxicity of cisplatin on ACHN cells was assessed in a dose- and time-dependent manner after siScramble or siNQO1 treatment. After cisplatin treatment, cells were subjected to cell viability assay, western-blot analysis, and immunofluorescence study. The cell viability was decreased in the siNQO1 cells (50%) than the siScramble cells (70%) after 24 h of cisplatin ($20{\mu}M$) treatment. Moreover, cytoprotection-related protein expressions were markedly suppressed in the siNQO1 cells after cisplatin treatment. The expression of Nrf2 and Klotho were decreased by 20% and 40%, respectively, of that in siScramble cells. Nrf2 and Klotho activation were also decreased in cisplatin treated siNQO1 cells, confirmed by cytoplasm-tonuclear translocation. Our findings demonstrate that the increased cisplatin-induced cytotoxicity was accompanied by suppressed Nrf2 activation and Klotho expression in siNQO1 cells.

• Archives of Pharmacal Research
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• v.18 no.5
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• pp.314-319
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• 1995

Antacid granules were prepared by agglomeration and powder method in high speed agitation type granulator. The copmositions of the test antacids were sodium bicarbonate nad magnesium carbonate nad a coating material was powder of polyvinylacetal diethyl-aminocacetate (AEA) and an additive material was talc powder. The dissolution characteristics of base from the antacid granules were investigated to evaluate neutralization capacity of hydrochloric profile of base and neutralization behavior, the following results were obtained : The prepared granules showed a pH-dependent dissolution pattern of a base. The dissolution profile of a base was varied with addition of talc powder as well as coating amount of AEA. The relationship between the ratio of dissolution retarded time for 20% and 10% AEA. The relationship between the ratio of dissolution retarded time for 20% AEA coated granules $\theta_{20}/\theta_{10}$ and the diameter reduction of the granules was explained by the rate process of neutralization of hydrochloric acid.

• Radiation Oncology Journal
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• v.31 no.2
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• pp.57-65
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• 2013

Beta-lapachone (${\beta}$-Lap; 3,4-dihydro-2, 2-dimethyl-2H-naphthol[1, 2-b]pyran-5,6-dione) is a novel anti-cancer drug under phase I/II clinical trials. ${\beta}$-Lap has been demonstrated to cause apoptotic and necrotic death in a variety of human cancer cells in vitro and in vivo. The mechanisms underlying the ${\beta}$-Lap toxicity against cancer cells has been controversial. The most recent view is that ${\beta}$-Lap, which is a quinone compound, undergoes two-electron reduction to hydroquinone form utilizing NAD(P)H or NADH as electron source. This two-electron reduction of ${\beta}$-Lap is mediated by NAD(P)H:quinone oxidoreductase (NQO1), which is known to mediate the reduction of many quinone compounds. The hydroquinone forms of ${\beta}$-Lap then spontaneously oxidizes back to the original oxidized ${\beta}$-Lap, creating futile cycling between the oxidized and reduced forms of ${\beta}$-Lap. It is proposed that the futile recycling between oxidized and reduced forms of ${\beta}$-Lap leads to two distinct cell death pathways. First one is that the two-electron reduced ${\beta}$-Lap is converted first to one-electron reduced ${\beta}$-Lap, i.e., semiquinone ${\beta}$-Lap $(SQ)^{{\cdot}-}$ causing production of reactive oxygen species (ROS), which then causes apoptotic cell death. The second mechanism is that severe depletion of NAD(P)H and NADH as a result of futile cycling between the quinone and hydroquinone forms of ${\beta}$-Lap causes severe disturbance in cellular metabolism leading to apoptosis and necrosis. The relative importance of the aforementioned two mechanisms, i.e., generation of ROS or depletion of NAD(P)H/NADH, may vary depending on cell type and environment. Importantly, the NQO1 level in cancer cells has been found to be higher than that in normal cells indicating that ${\beta}$-Lap may be preferentially toxic to cancer cells relative to non-cancer cells. The cellular level of NQO1 has been found to be significantly increased by divergent physical and chemical stresses including ionizing radiation. Recent reports clearly demonstrated that ${\beta}$-Lap and ionizing radiation kill cancer cells in a synergistic manner. Indications are that irradiation of cancer cells causes long-lasting elevation of NQO1, thereby sensitizing the cells to ${\beta}$-Lap. In addition, ${\beta}$-Lap has been shown to inhibit the repair of sublethal radiation damage. Treating experimental tumors growing in the legs of mice with irradiation and intraperitoneal injection of ${\beta}$-Lap suppressed the growth of the tumors in a manner more than additive. Collectively, ${\beta}$-Lap is a potentially useful anti-cancer drug, particularly in combination with radiotherapy.

• 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.