• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.1015-1018
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• 1998

Capsaicin(8-methyl-N-vanillyl-6-nonenamide: CAP) known well as a major compound of not taste in hot pepper, was investigated for the inhibition effect on in vitro nitrosation. CAP(100$\mu$mol) inhibited the formation of N-nitrosoproline(NPRO) and N-nitrosothioproline(NTPRO) by 56% and 26%, respectively. Vanillyl alcohol inhibited the nitrosation of proline by a concentration-dependent manner, and vanillic acid and vanillin were less effective in blocking the nitrosation of proline compared to CAP and anillyl alcohol. The inhibitory effect of NPRO formation by CAP was evaluated to similar with alpha-tocopherol, and vanillyl alcohol was more effective than alpha-tocopherol in blocking the nitrosation of proline. Our results suggested that CAP and its metabolites such as vanillyl alcohol could inhibit endogenous nitrosation in hydrophobic biological environment.

• Bulletin of the Korean Chemical Society
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• v.26 no.7
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• pp.1125-1128
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• 2005

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.420-423
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• 1994

Various N'-substituted anilino-N-methyl-N'-nitrosoureas(2a-n) were easily prepared from the reaction of substituted phenylhydraines $(3, 4-CH_3, {\;} 3-, {\;} 4-OCH_3, {\;} 3-, {\;} 4-F, {\;} 3, {\;} 4-Cl, {\;} 4-Br, {\;} 2-, {\;} 3-, {\;} 4-NO_2, 4-(NO_2)_2)$ with methyl isocyanate, followed by the nitrosation with 99% HCOOH and dry sodium lnitrite powder. Surprisingly, of these series of analogus, the anilino-nitrocosureas substituted with eletron-withdrawing nitro groups (2k-a) showed significantly low $ED_{30}$ values of $1.4-3.4 {\mu}g/ml.$ In addition, none of these copounds subtituted with electron-donating groups exhibited cytotoxicities.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.173-176
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• 1994

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.297-302
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• 2005

The determination of total phenols was accomplished by capillary-high performance liquid chromatography (capillary-HPLC) after nitrosation of the U.S.E.P.A. classified 11 priority pollutant phenols, using the nitrosated parent phenol (POHNO) as a reference for calibration. The optimum mobile phase composition for this analysis was found by examining the effect of changing the percentage of acetonitrile (MeCN) in the mobile phase on retention factors (k values) and peak intensities. As MeCN percentage was increased, k values were reduced and peak intensities were generally increased. From the results obtained, it was found that the optimum mobile phase was 90%(v/v) MeCN solution at pH 8.0, the detection wavelength of 400 nm, and a detection limit (D.L., concentration at signal to noise ratio (S/N) of 3.0) of 4.5 ${\times}$ $10^{-7}$ M. In addition, 10 of the 11 phenols present in mineral or waste water were separated after the nitrosation by capillary-HPLC. The optimum mobile phase for separation was a 40%(v/v) MeCN solution at pH 5.0.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.37-41
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• 1992

The reactions of nitrous acid with hydrogen peroxide in acidic aqueous solution in the presence of several added anions have been studied at $0^{\circ}C$ and pH 2-4 to investigate the nucleophilic catalysis of these anions. From the dependence of reaction rates on the anion concentrations, significant catalytic effects were found for $Cl^-,\;Br^-,\;SCN^-$, in order of effect $SCN^-\;{\approx}\;Br^->Cl^-$, while no observable effect was found for ${ClO_4}^-$ and ${NO_3}^-$. These results support O-nitrosation reaction is the rate-determining step and NOX formed in the presence of an anion ($X^-$) also acts as a nitrosating agent and accelerates the overall reaction rate. The order of reactivity was found to be NOCl>NOBr>NOSCN, which is consistent with the results of N-nitrosation and S-nitrosation reactions.

• Journal of the Korean Home Economics Association
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• v.23 no.3
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• pp.85-101
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• 1985

1. Nitrate and nitrite may contribute via nitrosation to the human exposure to N-nitroso compounds, especially nitrosamines, which are suspectd to be human carcinogens. 2. Since certain foods contain traces of nitrosamines, one should take the several points into consideration in evaluating the risk. 3. Nitrites, which can appear in the because of natural occurrence or deliberate addition, can react under the acidic conditions of the normal stomach with secondary amines to form nitrosamine. 4. Among the foods esamined, nitrate-nitrite treated meat products cooked bacon, and salted and dried fish are the main contributors of nitrosamines in our diet. 5. Consequently, in order to minimize human exposure to these chemicals, it is obviously essential to develop the alternative sources of nitrite in cured meat products. Thus the emphasis should be placed upon the most effective use of nitrite in curing with the use of acceptable inhibitors of nitrosation such as ascorbc acid or $\alpha$-tocopherol.

• YAKHAK HOEJI
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• v.27 no.2
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• pp.177-179
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• 1983

A copper complex of $\epsilon$-N-[(2-chloroethyl)carbamoyl]-L-lysine was prepared by the treatment of the L-lysine copper complex with 2-chloroethyl isocyanate in cold water. Within the L-lysine copper complex molecule, the $\alpha-amino$ and carboxyl groups are bounded to $Cu^{2+}$ but the $\epsilon-amino$ group is free and can react with carbamoylating agents. A potential antitumor agent, $\epsilon-N-[(2-chloroethyl)$ nitrosocarbamoyl]-L-lysine was synthesized by nitrosation of this copper complex with Na $NO_{2}$ in anhydrous formic acid, followed by the passage of $H_{2}$S gas.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.638-640
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• 2003

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.6-9
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• 1996

A total of 47 beer samples, produced in Korea. Were analyzed for their N-nitrosamine levels by gas chromatography-thermal energy analyzer. N-nitrosodimethyamine(NDMA) was detected in 35 of 47 sam-ples analyzed. The range of levels was 0~7.2$\mu\textrm{g}$/kg while the average was about 0.9mg/kg. The identity of NDMA was confirmed by mass spectrometry. Samples which were found only NDMA before nitrosation were detected to include N-nitrosopyrroidine(45$\mu\textrm{g}$.kg) and N-nitrosomorpholine(4$\mu\textrm{g}$/kg) as well as NDMA(837$\mu\textrm{g}$/kg)