• 한국축산식품학회지
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• 제24권4호
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• pp.373-385
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• 2004

Irradiation offers an effective and simple means to extend shelf-life of meat and improve processing properties of meat products. Many researches have been conducted to evaluate the effects of irradiation on meats and meat products. There were some interesting reports such as increase of redness and tenderness of meat and decrease of carcinogenic N-nitrosamines and residual nitrite in cured meat products by irradiation. And, the safety of irradiated products have been also studied. Lipid oxidation and off-odor induced by irradiation can be minimized by appropriate controls of irradiation and storage condition such as addition of antioxidants or oxygen exclusion packaging. The objective of this paper is to introduce the effect of gamma irradiation on quality of meats and meat products reported from the previous researches.

• Parasites, Hosts and Diseases
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• 제55권1호
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• pp.21-29
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• 2017

Schistosoma haematobium is a biocarcinogen of human urinary bladder (UB). The present study investigated developing UB cancer mouse model by injecting S. haematobium eggs into the bladder wall and introduction of chemical carcinogens. Histopathological findings showed mild hyperplasia to epithelial vacuolar change, and high grade dysplasia. Squamous metaplasia was observed in the S. haematobium eggs+NDMA group at week 12 but not in other groups. Immunohistochemistry revealed significantly high expression of Ki-67 in urothelial epithelial cells of the S. haematobium eggs+BBN group at week 20. The qRT-PCR showed high expression of p53 gene in S. haematobium eggs group at week 4 and S. haematobium eggs+BBN group at week 20. E-cadherin and vimentin showed contrasting expression in S. haematobium eggs+BBN group. Such inverse expression of E-cadherin and vimentin may indicate epithelial mesenchymal transition in the UB tissue. In conclusion, S. haematobium eggs and nitrosamines may transform UB cells into squamous metaplasia and dysplasia in correlation with increased expression of Ki-67. Marked decrease in E-cadherin and increase in p53 and vimentin expressions may support the transformation. The present study introduces a promising modified animal model for UB cancer study using S. haematobium eggs.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1722-1728
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• 2012

During the analyzing processes of the compounds, some researchers are puzzled by the analytical signals for some TSNAs (with or without splitting peaks at various pHs and temperatures). In this work, a detailed theoretical study of structural and thermal properties of the $E/Z$ isomers of TSNAs and the corresponding protonated structures was performed using DFT methods. The calculations showed that the $E$ isomers are almost stable than $Z$ isomers, while the $Z$ isomers would be more stable when in protonation. The calculated results predicted the possibility of separation of their $E$ and $Z$ isomer forms and also showed that protonation affects the dipole moment of molecules significantly (0.1-0.5 to 0.7-2.1 Debye). The calculations agreed well with the experiments that the split-up of the HPLC signal for TSNAs into two peaks are very sensitive to the pH and temperature of the mobile-phase.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3335-3340
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• 2016

Background: Oral submucous fibrosis (OSF) is a precancerous condition with a 4 to13% malignant transformation rate. Related to the habit of areca nut chewing it is mainly prevalent in South-east Asian countries where the habit of betel quid chewing is frequently practised. On chewing, alkaloids and polyphenols are released which undergo nitrosation and give rise to N-nitrosamines which are cytotoxic agents. CYP450 is a microsomal enzyme group which metabolizes various endogenous and exogenous chemicals including those released by areca nut chewing. CYP1A1 plays a central role in metabolic activation of these xenobiotics, whereas CYP2E1 metabolizes nitrosamines and tannins. Polymorphisms in genes that code for these enzymes may alter their expression or function and may therefore affect an individuals susceptibility regarding OSF and oral cancer. The present study was therefore undertaken to investigate the association of polymorphisms in CYP1A1 m2 and CYP2E1 (RsaI/PstI) sites with risk of OSF among areca nut chewers in the Northern India population. A total of 95 histopathologically confirmed cases of OSF with history of areca nut chewing not less than 1 year and 80, age and sex matched controls without any clinical signs and symptoms of OSF with areca nut chewing habit not less than 1 year were enrolled. DNA was extracted from peripheral blood samples and polymorphisms were analyzed by PCR-RFLP method. Gene polymorphism of CYP1A1 at NcoI site was observed to be significantly higher (p = 0.016) in cases of OSF when compared to controls. Association of CYP1A1 gene polymorphism at NcoI site and the risk of OSF (Odd's Ratio = 2.275) was also observed to be significant. However, no such association was observed for the CYP2E1 gene polymorphism (Odd's Ratio = 0.815). Our results suggest that the CYP1A1 gene polymorphism at the NcoI site confers an increased risk for OSF.

• 한국식품영양과학회지
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• 제46권2호
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• pp.244-250
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• 2017

Dimethylamine(DMA), 질산염, 아질산염, biogenic amines은 발암성 니트로사민의 전구물질이다. 본 연구는 국내 상품 김치로 유통되고 있는 국내산 배추김치, 깍두기, 총각김치, 맛김치, 묵은김치, 백김치의 김치 내 DMA, 질산염, 아질산염, biogenic amines의 오염도를 조사하였다. 배추김치 내 DMA, 질산염, 아질산염 함량은 각각 29.7, 2,178.8, 3.0 mg/kg이었다. 김치 종류 중에서 깍두기의 DMA와 질산염 함량이 가장 낮았다. Tryptamine, putrescine, cadaverine, tyramine, spermidine이 백김치와 총각김치를 제외한 분석된 김치 내 검출되었다. 백김치 내 tryptamine이 단지흔적량 존재하고 spermidine은 총각김치에서는 검출되지 않았다. 배추김치 내 tryptamine, putrescine, cadaverine, tyramine, spermidine의 함량은 각각 15.0, 64.6, 18.0, 44.0, 7.8 mg/kg이었다. 깍두기 내 tyramine의 함량이 낮았다. 깍두기 내 NDMA의 오염도를 분석하였고, 그 평균 함량은 $1.38{\mu}g/kg$이었다. 깍두기 1일 평균 섭취량과 체중을 근거로 깍두기 섭취군의 NDMA 인체노출량을 산출한 결과 깍두기 섭취로 인한 NDMA 노출량은 $2.31{\times}10^{-7}mg/kg\;b.w./d$로 나타났으며, 노출안전역(MOE)은 259,924로 위해 정도가 매우 낮은 안전한 수준으로 나타났다.

• 한국식품위생안전성학회지
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• 제12권4호
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• pp.333-339
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• 1997

The effects of kind of vegetables and of the kind and amounts of fermented fish sauce on the formation of nitrosamine (NA) during kimchi fermentation were investigated. Kimchies made of Chinese cabbage, cucumber, and radish with fermented shrimp, anchovy and liquid sauces were fermented at 4$^{\circ}C$ for 6 weeks and the changes in the content of nitrate, nitrite, trimethylamine (TMA), dimethylamine (DMA) and NA were studied. Nitrate content in kimchies made of Chinese cabbage, cucumber, and radish increased at the initial period of fermentation, but it decreased at the later period. Nitrite was not detected at the later period of kimchi fermentation. Overall, there have not been great changes in the contents of nitrite and nitrate. However, there have been considrable changes in the contents of TMA and DMA as fermentation progressed. Only nitrosodimethylamine (NDMA) at the level of 0.5~10.3 $\mu\textrm{g}$/kg was formed in three kinds of kimchies. More NDMA was formed in radish and cucumber kimchies than in Chinese cabbage kimchi. The pH was lowered faster in radish and cucumber kimchies than in Chinese cabbage kimchi. More NDMA was formed in Chinese cabbage kimchi made with fermented shrimp sauce than those with anchovy or liquid sauces. Shrimp sauce contained higher amount of DAM than anchovy and liquid sauces. The contents of NDMA tended to increase as the amount of shrimp sauce increased. The kind and amount of fermented fish sauce used for kimchi preparation may be an important factor affecting the formation of NDMA.

• Membrane and Water Treatment
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• 제8권3호
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• pp.245-257
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• 2017

The separation of nicotine and tobacco-specific N-nitrosamines is a tough problem in tobacco industry. In this study, separation of nicotine from 4-(methylnitrosamino) -1-(3-pyridyl)-1-butanone (NNK) mixtures was investigated using electrodialysis by taking the principle of the protonation status difference between these two components. The results indicated that the solution pH has a dominant impact on the separation process. In a pH range of 5-7, nicotine molecules are existed as mono- and di-protonated ions and can be separated from the uncharged NNK molecules. The acidic electrolyte is conducive to the separation process from the point of flux and energy consumption; while the alkaline electrolyte has negative impact on the separation process. A current density of $10mA/cm^2$ is an appropriate value for the separation process. The lowest energy consumption of the separation process is 0.58 kWh/kg nicotine with the process cost to be estimated at only $0.208 /kg nicotine. Naturally, electrodialysis is a high-efficiency, cost-effective, and environmentally friendly process to separate and purify nicotine from tobacco juice.

• 분석과학
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• 제28권1호
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• pp.1-7
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• 2015

4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco specific nitrosamine found only in tobacco products. The ability to monitor biomarker concentrations is very important in understanding environmental tobacco smoke (ETS). In this study, an efficient and sensitive method for the analysis of NNK in dust was developed and validated using liquid chromatography tandem mass spectrometry. Dust was collected with filter paper soaked in methanol. The standard solution and dust sample were diluted with 100 mM ammonium acetate and extracted using dichloromethane. Our calibration curves ranged from 25 to $10^4pg/mL$. Excellent linearity was obtained with correlation coefficient values between 0.9996 and 1.0000. The limit of detection (LOD) was 5 pg/mL ($S/N{\geq}3$) and the retention time was 10 min. The limit of quantification (LOQ) was 25 pg/mL, and the acceptance criteria was the rate of 98-103% (80-120% at levels up to $3{\times}LOQ$). The coefficient of variations (CV) was 2.8%. Accuracies determined from dust samples spiked with four different levels of NNK racurves ranged that from 25 to 104 pg/mL. Excellent linearity was obtained between 92.1% and 114%. The precision of the method was acceptable (5% of CV). The recovery rates of the whole analytical procedure at low, medium, and high levels were 105.7-116.5% for NNK. The carry-over effects during LC-MS/MS analysis were not observed for NNK. This manuscript summarizes the scientific evidence on the use of markers to measure ETS.

• 한국수산과학회지
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• 제14권1호
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• pp.7-14
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• 1981

꽁치($2^{\circ}C$와 $10^{\circ}C$) 및 삼치육($2^{\circ}C$와 $15^{\circ}C$)은 저장하였을 때의 육중의 TMAO-N, TMA-N 및 TMA-N의 경시적인 변화와 아울러 이들 어육을 저장, 열풍건조 및 일건하였을 때의 변화에 대하여 실험하여 다음과 같은 결과를 얻었다. 1. TMAO의 변화에 있어서 5일간 저장하였을 때 $2^{\circ}C$의 경우, 꽁치 몇 삼치육은 각각 생시료때의 $48\%$ 및 $41\%$의 잔존율을 나타내었고 $10^{\circ}C$의 꽁치육과 $15^{\circ}C$의 삼치육의 경우는 각각 $39\%$ 및 $18\%$였다. 2. TMA의 변화는 5일간의 저장에서, $2^{\circ}C$의 경우 꽁치 및 삼치육은 각각 생시료때의 6.5배양 및18배양의 증가를 보었고, $10^{\circ}C$의 꽁치와 $15^{\circ}C$의 삼치육의 경우는 각각 28.8배양 및 77.7배양이었다. 3. DMA의 변화는 5일간의 저장에서, $2^{\circ}C$의 경우 꽁치 및 삼치육은 각각 생시료때의 2.5배양 및 5.4배양의 증가를 나타냈고, $10^{\circ}C$의 꽁치와 $15^{\circ}C$의 삼치육의 경우는 각각 4배양 및 8배양이었다. 4. 제품별 TMAO의 함양은 꽁치의 경우, 염장품 > 열풍건조품 > 일건품의 순이었고 삼치의 경우는 염장품 > 일건품열풍건조품의 순이 있다. 5. 제품별 TMA의 합양은 꽁치의 경우, 열풍건조품 > 일건품 > 염장품의 순이였고 삼치의 경우는 일건품 > 열풍건조품 > 염장품의 순이었다. 6. 제품별 DMA의 함양은 모든 시료가 열풍건조품 > 일건품 > 염장품의 순이었다. 본 연구의 실험을 도와 준 성혜경 선생에게 감사를 드리는 바이다.

• 한국수산과학회지
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• 제27권3호
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• pp.247-258
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• 1994

우리나라 수산 건제품중 발암성 N-Nitrosamine(NA)의 생성요인을 구명하기 위하여 시판 되고있는 소건품 10종(17개 시료), 조미건제품 1종(3개 시료), 자건품 3종(5개 시료), 염건품 1종(1개 시료), 동건품 1종(3개 시료) 및 해조류 2종(2개 시료)에 대하여 NA의 전구물질인 아민류, 질산염 및 아질산염을 분석하였고, GC(Gas Chromatography)-TEA(Thermal Energy Analyzer)를 이용하여 NA를 분석 정량하였으며, 또 GC-MS(Mass Spectrometry)로 N-Nitrosodimethylamine (NDMA)을 동정하였다. 수산 건제품의 아민류는 대체로 betaine질소가 다른 아민류에 비해 월등히 높아 건조 문어에서 $357.4{\sim}373.8mg\%$로 가장 많았고, 다음으로 건조새우 및 건조 오징어순이었다. 그러나 건조 해조류에서는 전혀 검출되지 않았다. TMAO질소는 $2.2{\sim}20.7mg\%$ 범위였으나, 건조해삼에서는 흔적량이었고, 건조 해조류에서는 전혀 검출되지 않았다. TMA질소는 TMAO질소에 비해 대체로 높게 정량되어 건조 상어에서 $57.2mg\%$, 건조 옥돔 $40.1mg\%$ 였으며, 그외 건조 해조류와 건조해삼을 제외한 모든 시료에서 $10.0mg\%$ 이상이었다. 분석된 시료중 dimethylamine(DMA) 역시 건조 해조류와 건조 해삼을 제외한 모든 시료에서 검출되었는데 비교적 함량이 높은 시료는 건조 상어(31.2 ppm), 동건 명태($22.9{\sim}24.3\;ppm$) 및 건조문어 ($17.9{\sim}18.4\;ppm$)등이었다. 질산염 질소는 불검출에서 최고 16.8 ppm범위였는데 건조 가오리(16.8ppm), 동건 명태(16.3ppm) 및 건조 오징어($2.2{\sim}12.4ppm$) 등에서 높은 함량을 보였으나, 그외 시료에서는 1.0 ppm미만이었다. 아질산염 질소는 질산염 질소에 비해 다소 낮은 경향을 보여 건조 해조류 및 건조 해삼에서는 전혀 검출되지 않았으나, 반면에 건조 가오리에서는 최고 9.6 ppm으로 정량되었다. NDMA의 농도는 시료간에 큰 함량차를 보여 건조 해조류 및 건조 해삼에서는 전혀 검출되지 않았으나, 건조 가오리($2.8{\sim}86.0ppb$), 동건 명태($8.2{\sim}55.5ppb$), 건조 오징어($3.3{\sim}53.2ppb$), 굴비(45.9ppb) 및 소건 새우($15.4{\sim}17.9ppb$) 등에서는 높은 함량을 보였으며 그외 시료에서는 10ppb미만 이였다. 대체로 NDMA가 높게 검출된 시료에서는 질산염과 아질산염질소의 함량이 높아 이들이 NBMA의 생성에 주된 요인이라는 것을 알 수 있었고, 동일 어종간에도 시료에 따라 함량차가 심한 것도 역시 질산염과 아질산염의 오염 정도에 의한 것으로 판단된다.