• Culinary science and hospitality research
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• v.10 no.2
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• pp.30-37
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• 2004

국내에서 유통되고 있는 수입어류 8종에 대한 발암성 물질인 N-nitrosamine콰 전구물질들의 함량을 분석하여 위생학적 기초자료를 제공하고자 하였다. 수입어류의 질산염 및 아질산염 함량은 각각 0.4∼12.8 mg/kg 및 N.D∼l6.0 mg/kg 이었다. Dimethylamine 함량은 1.0∼70.6 mg/100g 이었으며, Trimethylarnine 함량은 15.4∼70.6 mg/100g이었다. 수입어류 8종에 대한 발암성 물질인 N-nitrosamine은 N-nitrosodimethylamine (NDMA) 만 검출되었으며, 이들의 NDMA 함량은 2.1∼102.2mg/kg으로 러시아산 가자미에서 가장 높게 검출되었다. 또한 아르헨티나산 냉동새우는 35.3 $\mu\textrm{g}$/kg, 러시아산 냉동대구에서도 30.6 $\mu\textrm{g}$/kg으로 높은 함량을 보였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.28-32
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• 1999

A total of 18 marketing radish kimchi samples, 7 species of kakdugi, 6 species of chonggak kimchi and 5 species of dongchimi were analyzed for their N nitrosamine levels by gas chromatography thermal energy analyzer(GC TEA). N nitrosodimethylamine(NDMA) was the only volatile N nitr osamine found in this study and was positive in all collected samples. The average amount of NDMA for kakdugi, chonggak kimchi and dongchimi were 22.9, 13.7 and 23.4 g/kg, and the range were 3.3~ 35.9, 2.6~50.6 and 4.5~65.1 g/kg, respectively. The range of pH for all samples were 3.6~5.4 and the average recovery of internal standard(N nitrosodipropylamine) were 82.0%. NDMA amounts were highest in chonggakkimch (50.6 g/kg) and dongchimi(65.1 g/kg) among collected samples.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.83-84
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• 1980

• Journal of the Korean GEO-environmental Society
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• v.13 no.2
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• pp.75-81
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• 2012

Because N-Nitrosodimethylamine(NDMA) is well-known as a potential carcinogen, extensive research has addressed its treatment by ultraviolet(UV) and its degradation pathway. However, the detailed mechanism by which NDMA is photolyzed to form oxidized products, i.e., ${NO_2}^-$ and ${NO_3}^-$, is still not understood. This study reveals a key reactive species during the photolysis of NDMA. The study on a key reactive species was indirectly performed with the formation of nitrogen oxidized products and reactions between methanol and an unknown reactive species formed during the photolysis of NDMA. The peroxynitrite($ONOO^-$) generated by the direct UV photolysis of NDMA would be identified as a key reactive species in oxidizing nitrogen intermediates to ${NO_2}^-$and ${NO_3}^-$.

• Toxicological Research
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• v.31 no.3
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• pp.279-288
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• 2015

N-nitrosamines, which are classified as carcinogens by IARC and US EPA, can be easily found in various foods. They are reaction products between nitrogen oxide and secondary amines, but can also be generated during fermentation. Ever since the 1960s, when nitrite, used as a preservative in processed meats, was suspected to generate N-nitrosamines, the usage of the food additive has been debated. However, the benefit of nitrite in food supply could not be ignored and the risk-benefit analysis has become a key issue in the use of the additive. For a risk analysis, an accurate estimation of the hazardous material is necessary; therefore, analytical methods for nitrosamines have continuously evolved from the 1950s. Solid supported liquid-liquid extraction and solid phase extractions have replaced the distillation for the clean-up steps, and tandem mass spectrometry is employed for higher selectivity and sensitivity. In the present study, for a better estimation of N-nitrosamine intake, the total diet study samples were prepared for the N-nitrosamines analysis. In order to obtain the most sensitive results, a partial preparation procedure was developed and modified for different food matrices. Among seven N-nitrosamines (N-nitrosodimethylamine, N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitrosodibutylamine, N-nitrosopiperidine, N-nitrosopyrrolidine, and N-nitrosomorpholine) analyzed in the present study, N-nitrosodiethylamine has shown the highest detection rate in agricultural foods, while N-nitrosodimethylamine has appeared most frequently in livestock and fishery food products. The concentration of N-nitrosodimethylamine was the highest in seasoning.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.97-103
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• 2002

Five citrus juices were separated into a ascorbate and phenolic portion using rep-pak C$\_$18/ cartridge, respectively, in order to elucidate the nitrite scavenging effect and N-nitrosodimethylamine(NDMA) formation in model system. The nitrite scavenging effect of ascorbate portion from citrus juices, in the different pH, when added with 5ml were 79.9 ∼98.6% under the condition of pH 2.5. 48.5∼86.3% at pH 4.2 and lower than 35.2% at pH 6.0. The nitrite scavenging effect was excellent phenolic portion rather than ascorbate portion. Particularly, the effect was more 2 times than ascorbate portion under the reaction condition of pH 6.0. When added the phenolic portion in the reaction mixture, NDMA formation was inhibited 92.8% or more in kum quat, mandarin orange and sweet orange juices. But the ascorbate portion was a negative response of the inhibition of NDMA formation. The inhibition on NDMA formation in citrus juice may be due to phenolic compounds were reacted.

• Journal of Food Hygiene and Safety
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• v.17 no.4
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• pp.201-205
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• 2002

When it added to each designed diet groups such as control, nitrate rich, amine rich and nitrate-amine rich diet under simulated gastric conditions, effect of kumquat (Fortunella mararita) juice on formation of N-nitrosodimethylamine (NDMA) was studied. Inhibition on NDMA formation was the highest in the amine rich diet, as 69.4 $\pm$2.4%, when the juice of 10m1 added to its digestate. Phenolic portion of $C_{18}$ sep-pak cartridge in kumquat juice were separated into 20 kinds of a phenolic compounds using HPLC. These phenolic fractions such as faction no. 1, 2, 3, 4 and 5 inhibited from 3.0 $\pm$ 1.2% to 66.5 $\pm$2.0% NDMA formation in the reaction system which was mixture of nitrite and dimethylamine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.137-142
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• 1994

The present paper was carried out to investigate the inhibition of carcinogenic N-nitrosodimethylamine(NDMA) formation by Maillard reactiion products and nondialyzable melanoidins, obtiane dfrom the glucoseamino acids(Lys, Gly, Arg, His) model systems under different pH conditions(pH 1.2, 4.2 and 6.0). Maillard raction products and nondialyzable melanoidins, produced from the 4 model systems, had a inhibitory action of N-nitrosodimethylamine formation. The inhibitiondegree by the nondialyzable mealanoidins. at pH 1.2 was similar to that at pH 4.2 and that by ascorbic acid at pH 1.2 . Inhibitory action of N-nitrosodimehylamine formation by the reduced Maillard reaction products and nondialyzable melanoidins were lower than that of original samples. Accordingly, it is assumed that the inhibition of N-nitrosodimehtylamine formation of Maillard reaction products is due to their reducing powers.

• Environmental Engineering Research
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• v.24 no.1
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• pp.1-16
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• 2019

N-nitrosodimethylamine (NDMA) is a typical nitrogen disinfection by-product, which has posed a potential threat to human health during drinking water disinfection. Because of the well-known effects of mutagenesis, carcinogenesis and teratogenesis, the high detection rate in water engineering systems (such as coagulation, membrane filtration and biological systems), and difficulty to remove, it has received wide concern in the field of water engineering systems. The NDMA is a low molecular weight hydrophilic organic substance, which is difficult to remove. Also, the mechanism for NDMA formation is also recognized to be complex, and many steps still needed to be further evaluated. Therefore, the mechanistic knowledge on NDMA formation potential and their removal processes is of particularly interest. Few papers summarize the occurrence and control of NDMA in water engineering systems. It is for this reason that the content of this paper is particularly important for us to understand and control the amount of NDMA thus reducing the threat of disinfection by-products to drinking water. Four parts including the mechanisms for the NDMA formation potential, the factors affecting the NDMA formation potential, the technologies for removal of NDMA are summarized. Finally, some definite suggestions are given.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.223-228
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• 2006

High-performance liquid chromatography(HPLC) and fluorescence derivatization were applied for a trace-level N-nitrosodimethylamine(NDMA) analysis of water samples. Fluorescence intensity was optimized with the excitation wavelength of 340 nm and the emission wavelength of 530 nm. pH adjustment after denitrosation was necessary to get a maximum intensity at pH between 9 and 12. Maximum intensity was found with a dansyl chloride concentration of 330 to 500 mg/L. Percentile error in the water sample analyses through solid phase extraction was 12-162% and 6-23% for the lower concentration level(10-200 ng/L NDMA) and the higher level(100-1000 ng/L NDMA), respectively, showing more discrepancy in lower level. However, the average ratios of estimated NDMA to the standard NDMA were close to 1 for both concentration ranges, presenting this HPLC method could detect from tens to hundreds nanograms NDMA per liter. Accurate determination of NDMA, which was injected to a wastewater effluent, revealed the selectivity of fluorescence derivatization for the target compound(NDMA) in the presence of complex interfering compounds. The HPLC with fluorescence derivatization may be applicable for determining NDMA of water and wastewater samples fur various research purposes.