• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1080-1086
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• 2005

Membranes prepared from Vibrio natriegens oxidized both NADH and deamino-NADH as substrates. The maximum activity of the membrane-bound NADH oxidase was obtained at about pH 8.5 in the presence of 0.2 M NaCl, whereas that of the NADH:ubiquinone oxidoreductase was obtained at about pH 7.5 in the presence of 0.2 M NaCl. Electron transfer from NADH or deamino-NADH to ubiquinone-l or oxygen generated a considerable membrane potential (${\Delta}{\psi}$), which occurred even in the presence of $20{\mu}M$ carbonylcyanide m-chlorophenylhydrazone (CCCP). However, the ${\Delta}{\psi}$ was completely collapsed by the combined addition of $10{\mu}M$ CCCP and $20{\mu}M$ monensin. On the other hand, the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were inhibited by about $90\%$ with $10{\mu}M$ HQNO, whereas the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were inhibited by about $60\%$. Interestingly, the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were resistant to the respiratory chain inhibitors such as rotenone, capsaicin, and $AgNO_3$, and the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were very sensitive only to $AgNO_3$. It was concluded, therefore, that V. natriegens cells possess a $AgNO_3$-resistant respiratory $Na^+$ pump that is different from the $AgNO_3$-sensitive respiratory $Na^+$ pump of a marine bacterium, Vibrio alginolyticus.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.158-166
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• 2000

The effects of smoking and physical exercise on the plasma concentrations of lipid-soluble antioxidants were investigated in 62 healthy males, aged 34-65 years. Current smokers (n=21) and ex-smokers(n=16) had significantly lower plasma levels of carotenoids ($\alpha$-carotene, $\beta$-carotene, cryptoxanthin and lycopene), $\alpha$-tocopherol and ${\gamma}$-tocopherol than non-smokers (n=25). Plasma concentrations of retionl and ubiquinone (coenzyme Q10) were lower among ex-smokers and current smokers than among non-smokers, but the differences were not statistically significant. Regular physical exercise was associated with increased plasma levels of lipid-soluble antioxidants. Plasma concentrations of crytoxanthin, retinol and ubiquinone were significantly elevated in the group engaging in moderate amounts of exercise (more than 20 minutes per day) compared to the group engaging in small amounts of exercise (less than 10 minutes per day). Plasma $\alpha$-carotene, $\beta$-carotene, lycopene levels in the subjects were affected more by smoking than by exercise. However, plasma levels of cryptoxanthin, retinol and ubiquinone in the subjects were affected more by exercise than by smoking. These findings suggest than smoking may cause a decrease in plasma lipid-soluble antioxidants during neutralization of reactive oxygen species present in cigarette smoke and that poor exercise habits may accelerate this imbalance of oxidant/antioxidant homeostasis in middle-aged Korean men.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.438-439
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• 1991

• Proceedings of the Korean Society of Crop Science Conference
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• 1991.05a
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• pp.108-109
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• 1991

• 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.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.509-513
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• 1997

The photosynthetic bacteria, Rhodopseudomonas capsulata H161, were grown anaerobically in the Modified Ormerod medium for 5 days. The optimum temperature and pH for growth and carotenoid pigment of the organism were observed at 3$0^{\circ}C$, and around pH 7.4, respectively. The optimum condition of producing the carotenoid pigment, light intensity 5,000 lux. The photosynthetic bacteria, Rhodopseudomonas capsulata H161, produced large amount of carotenoid pigment, which identified to 4 carotenoid components containing; spheroidene, rhodovibrin, spirilloxanthin, lycopene.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.68-69
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• 1996

The isoprenoid quinone composition of Leclercia adecarboxylata KCTC $1036^T$ was determined by using high-performance liquid chromatography. L. adecarboxylata KCTC $1036^T$ are characterized by their production of both ubiquinone-7, ubiquinone-8 and menaquinone-8 as major quinones. It is clear that the analysis of isoprenoid quinone profiles provides a new criterion of great promise for identifying Leclercia strains.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.131-131
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• 2003

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.38-38
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• 2002

• The Korean Journal of Pharmacology
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• v.23 no.2
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• pp.113-121
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• 1987

Local anesthetics were investigated for their effects on mitochondrial electron transport system, production of superoxide radical from submitochondrial particles and malondialdehyde production through lipid per oxidation. Local anesthetics had various effects on activities of enzymes in electron transport chain. The activities of NADH dehydrogenase, NADH oxidase and NADH-ubiquinone oxidoreductase were effectively inhibited by lidocaine, procaine and dibucaine but slightly influenced by cocaine. The activities of succinate dehydrogenase, succinate-cytochrome c oxidoreductase and succinate-ubiquinone oxidoreductase were inhibited by lidocaine and dibucaine, but the succinate oxidase activity was stimulated by local anesthetics. Both dihydroubiquinone-cytochrome c oxidoreductase and cytochrome c oxidase activities were inhibited by local anesthetics. In these reactions, the response of Complex I segment to local anesthetics was greater than other Complex segments. Local anesthetics inhibited both the superoxide production from submitochondrial particles supplemented with succinate or NADH and the enhanced production of superoxide radicals by antimycin. The malondialdehyde production by oxygen free radicals was inhibited by local anesthetics. These results suggest that the inhibition of superoxide and malondialdehyde production caused by local anesthetics may be brought by suppression of the electron transport in mitochondria at sites in or near complex I segment.