• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.21-26
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• 2009

Polycyclic aromatic hydrocarbon(PAH) contents were evaluated in sesame oils from sesame seeds of different origins and in commercial samples using HPLC with fluorescence detection. The sesame seeds, which had been harvested from India, China, and Korea, were roasted at $250^{\circ}C$ for 25 min, and the commercial sesame oils were purchased from a local market. The recoveries for eight PAHs spiked into the sesame oils ranged from 80.2 to 99.2%. The mean levels of total PAHs in the sesame oils harvested from China, Korea, and India were 3.97, 1.57, and 1.20 ${\mu}g$/kg, respectively. The PAH contents in the commercial sesame oils ranged from 0.79 to 2.15 ${\mu}g$/kg.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.355-361
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• 2009

Polycyclic aromatic hydrocarbons (PAHs) are environmental carcinogenic compounds that arise by several means including food processing methods such as smoking and direct drying and cooking. This study examined the concentration of PAHs in sesame oils with various roasting temperatures (190, 220 and $250^{\circ}C$), methods (direct heating vs. indirect hot air heating), and times (5, 10, 15, 20 and 25 min). The PAHs in the sesame oils were analyzed using liquid-liquid extraction and solid-phase clean up (Florisil), followed by HPLC with fluorescence detection. According to the results, mean levels of total PAHs increased when the sesame oils were roasted at increasing temperatures and times. The sesame oil roasted at $250^{\circ}C$ for 25 min had the highest mean value of total PAHs (4.66 ${\mu}g$/kg). The results of this study suggest that the indirect hot air roasting method decreased PAH formation during sesame oil processing.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.91-101
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• 2000

The emission sources of volatile organic compounds (VOCs) are wastewater treatment plants. sanitary landfills, automobile industries, and so on. The VOCs are harmful to human beings because of their toxicity and carcinogenicity, and cause the serious air pollution problem producing ozone ($O_3$) as a result of photochemical reaction. To investigate the emission of VOCs from wastewater treatment plant, aeration basins at the City of Los Angeles' Hyperion Treatment Plant were selected and measured flux was compared with calculated flux. For compounds commonly associated with wastewater (DCM, TCM, PCE, UM, DCB, UND) and not expected in vehicle exhaust or ambient air coming off the ocean, concentrations immediately downwind of the aeration basins were a factor of ten or higher than those measured in the upwind air. The airborne flux of less degradable or non-biodegradable compounds, e.g., DCE, DCM, TCA, DCA, TCM, PCE, DCB, through an imaginary plane at the downwind side of the aeration basins was in agreement with the estimated flux from measured liquid phase concentrations. Henry's constant. aeration rate, and an assumption of bubble saturation. For several compounds (PCE, DCE, TCA), the ratio (measured flux/calculated flux) is almost unity.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.129-133
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• 1986

To know the three questions about multiple primary cancers: 1) what are the characteristics of persons having multiple parimary cancer? 2) Does the presence of a single primary concer after the susceptability to multiple primary cancers? 3) Does the location of one multiple primary cancer influence the site of others?, we analysed 121 cases of multiple primary malignant neoplasms registered in Seoul National University Hospital during 8 years from July 1978 to August 1986. Of 121 cases, double primary malignant neoplasms were 119 cases and triples were 2 cases. The incidence of multiple primary malignant neoplasms was $0.7\%$. The metachronous tumor (>6 months) was found in 70 cases and the median time between the first and the second was 32 months. The most commonly associated tumors were stomach and primary liver carcinoma. Cervix and Lung cancer, Stomach and Rectal cancer, Stomach and Esophagus cancer were also commonly associated.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.719-725
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• 2009

Heterocyclic aromatic amines (HCAs) are potent mutagens and possible human carcinogens that are formed during the heating of protein-rich foods. The effects of preheating treatment of beef patties using a microwave prior to frying at $220^{\circ}C$ for 10 min on each side on the reduction of HCAs (amino-carbolines and amino-imidazo-azaarenes) were evaluated. The amount of HCAs was then evaluated by solid-phase extraction and high pressure liquid chromatography (HPLC) analysis. The beef patties were treated by microwaving for various times (0, 1, 1.5, 2, or 3 min) before pan-frying. The results revealed the presence of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b] indole (Trp-P-1), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-aminodipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2), 9H-pyrido[3,4-b]indole (Norharman), 1-methyl-9H-pyrido[3,4-b]indole (Harman), 2-amino-9H-pyrido[2,3-b] indole ($A{\alpha}C$), 2-amino-3,8 dimethylimidazo[4,5-f]-quinoxaline (MeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine (PhIP) in all samples. However, microwave pretreatment for 1 min inhibited the formation of these HCAs by up to 90% when compared to the control.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.688-693
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• 2002

The anticarcinogenic effects of various food components have received much attention in recent years. However mechanism of anticarcinogens in food materials on cancer cells have rarely been investigated. This study was performed to investigate the effects on the cytotoxicity and quinone reductase (QR) activity of Allium tuberusum (AT) on the human cancer cells. The six partition layers which are methanol (ATM), hexane (ATMH), ethylether (ATMEE), ethylacetate (ATMEA), butaonl (ATMB) and aqueous (ATMA) of Allium tuberusum were screened for their cytotoxic effects on HepG2, MCF-7, HeLa and SK-N-MC cells by the MTT assay. Among the six partition layers, ATMEE had the strongest cytotoxic effect at concentration of $150\;{\mu}g/mL$ which resulted over 95% on HepG2, HeLa, MCF-7 and SK-N-MC cell lines. The ATMEA also showed significant cytotoxic effect on HepG2 and SK-N-MC cell lines. The ATMB showed the highest induction activity of QR on HepG2 cells among the other partition layers. QR activity of HepG2 cells, grown in the presence of ATMB at the concentration of $50\;{\mu}g/mL$, was increased by 3.9 times, compared to the control value of 1.0. Based on these results, the ATMEE and ATMB may have potentially anticarcinogenic and chemopreventive activities.

• Journal of Life Science
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• v.29 no.9
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• pp.1034-1046
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• 2019

The mitochondria is the major cellular organelle of energy metabolism for the supply of cellular energy; it also plays an important role in controlling calcium regulation, reactive oxygen species (ROS) production, and apoptosis. Mitochondrial dysfunction causes various diseases, such as neurodegenerative diseases, Lou Gehrig's disease, cardiovascular disease, mental disorders, diabetes, and cancer. Most of the diseases are age-related diseases. In this review, we focus on the roles of mitochondrial dysfunction in cancer. Mitochondrial dysfunction induces carcinogenesis and is found in many cancers. The factors that cause mitochondrial dysfunction differ depending on the types of carcinoma, and those factors could cause cancer malignancy, such as resistance to therapy and metastasis. Mitochondrial dysfunction is caused by a lack of mitochondria, an inability to provide key substances, or a dysfunction in the ATP synthesis machinery. The main factor associated with cancer malignancy is mtDNA depletion. Mitochondrial dysfunction would leads to malignancy through changes in molecular activity or expression, but it is not known in detail which changes lead to cancer malignancy. In order to explore the relationship between mitochondrial dysfunction and cancer malignancy in detail, mitochondria dysfunctional cell lines are constructed using chemical methods such as EtBr treatment or gene editing methods, including shRNA and CRISPR/Cas9. Those mitochondria dysfunctional cell lines are used in the study of various diseases caused by mitochondrial dysfunction, including cancer.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.316-322
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• 2019

Helicobacter pylori, a gram-negative bacterium, is one of the risk factors that induces gastritis and gastric cancer. Therefore, much attention has been paid to the compounds that inhibit bacterial growth or eradicate bacteria. Evodiae fructus (EF), the fruit of Evodia rutaecarpa, has been used for treating diarrhea and abdominal pain. EF extract was already found to inhibit the growth of H. pylori. However, to the best of our knowledge, the effect of EF on the virulence factors of H. pylori has not been reported. In this study, when comparing the minimum inhibitory concentration (MIC) of the different methanol concentration extracts, the 95% methanol extract (EF95) showed the lowest MIC value. EF95 extract suppressed the expressions of cagA, vacA and ureB, but interestingly, it up-regulated the expression of ureA. A decrease in production of ammonia in the culture medium and the cell lysates indicated that EF95 inhibited the urease activity in H. pylori, which was the result of EF95 inhibiting the ureB expression. Although the mechanism by which EF95 extract regulates the virulence factors in H. pylori needs further study, EF95 could be used for treatment of gastric troubles induced by H. pylori.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.587-601
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• 2020

Exposure to hazardous substances occurs through multiple pathways. Aggregated risk assessment, which includes all potential exposure pathways to a single toxicant, is necessary to prevent exposure to harmful substances. We aimed to estimate cadmium and lead exposure through various media, such as food, water, air, smoking, cosmetics, and female hygiene products. This study covered 10,733 subjects from the Seventh Korea National Health and Nutrition Examination Survey(2016, 2017). Dietary exposure was estimated using 24-hour recall data. For water and inhalational exposure, regional variations were considered. Water was classified as tap, bottled, and public water. Inhalational exposure was estimated using the '2014 Time Use Survey' based on daily lifestyle and social status. The frequency and volume of cosmetic usage were randomly approximated by sex and age. Post-menarcheal and premenopausal women were assumed to use feminine hygiene products. Non-carcinogenic aggregated risks were estimated using the Aggregate Risk Index from EPAs and the Total Exposure Hazard Index from Korean government guidelines. For carcinogenic risk assessment, excessive cancer risk was estimated. Ingestion, especially food, was the major route for both cadmium and lead exposure. Smoking was also associated with high cadmium exposure. Exposure to lead from cosmetics was remarkable but not critical. In aggregate risk assessments, median cadmium and lead exposure did not exceed the reference value. Sex, age, smoking status, and income affected exposure levels, unlike to regional variations.

• Membrane Journal
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• v.33 no.3
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• pp.94-109
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• 2023

1,3-Dioxolane is an exciting material that has attracted widespread interest in the chemical, paint, and pharmaceutical industries as a solvent, electrolyte, and reagent because 1,3-dioxolane is not toxic, carcinogenic, explosive, auto-flammable, and multifunctional, and due to their excellent miscibility in most organic and aqueous solvent conditions. Recently, this material has received increasing attention as a CO₂-selective polymer precursor to separating CO₂ from flue gas and natural gas mixtures. Poly(1,3-dioxolane) (PDXL) possesses higher ether oxygen content than polyethylene oxide (PEO), which demonstrates superior membrane CO₂/N₂ separation properties owing to their polar ether oxygen groups exhibiting strong affinity toward CO₂. Thus, PDXL-based membranes displayed an outstanding CO₂ solubility selectivity over non-polar (N₂, H₂, and CH₄) gases. However, the polar groups of PDXL, like PEO, promote chain packing efficiency and cause polymer crystallization, thereby reducing its gas permeability, which should be improved. In this short review, we discuss the recent advancement and limitations of PDXL membranes in gas separation applications. To conclude, we provide future perspectives for inhibiting the limits of 1,3-dioxolane-based polymers in the CO₂ separation process.