• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.501-505
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• 2017

Due to the rapid urbanization and increased population, there is an increase in airtight nature of buildings which causes serious indoor air pollution. Among several indoor air pollutants, volatile organic compounds (VOCs) emitted from paint are of major concern. Therefore, there is an urge for the development of environmental friendly paint products. In this wok, a natural wall paint (NWP) was prepared by utilizing a natural clay material "sericite" as a main component. A small chamber test was carried out to identify the toxic substances release from NWP and the results were compared with two eco-friendly commercial paints. The total VOCs were detected in trace level inside the test chamber and their concentrations were below the recommended indoor air quality standards. Toluene was not detected for NWP, whereas formaldehyde was observed in trace level. The toxicity index results were compared with two commercial paints and found that NWP exhibited less harmful gas emission. Based on certification rating of building materials, NWP can be classified as the first grade of building materials. Due to the above advantages, the use of sericite as a major component in NWP will be a useful technique to maintain the indoor air quality.

• Analytical Science and Technology
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• v.13 no.1
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• pp.55-65
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• 2000

In this study, we collected the tap water that treated from water plant in Seoul, Incheon, Taejon, Kwangju, Taeku and Pusan and supplied each house. The sampling period was June and September, 1997. The concentration of THMs formed by chlorination in drinking water was determined with the purge and trap method with GC/MSD recommended by the us EPA 542.2 method. Chloroform is the most of THMs (47.43%~93.11%) and the content order is bromodichloromethane > chlorodibromomethane > bromoform. In Incheon, Taejon, Kwangju, Taeku and Pusan, the content of bromodichloromethane, chlorodibromomethane and bromoform was higher than Seoul. But, in June and September, the concentration of THMs in six cities is not over Korea Drinking Water Regulation $100{\mu}g/L$. The calculated human exposure for each substances were chloroform $6.14{\times}10^{-4}mg/kg/day$, bromodichloromethane $1.01{\times}10^{-4}mg/kg/day$, chlorodibromomethane $0.29{\times}10^{-4}mg/kg/day$, bromoform $0.01{\times}10^{-4}mg/kg/day$ and THMs $7.98{\times}10^{-4}mg/kg/day$.

• Analytical Science and Technology
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• v.25 no.2
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• pp.91-101
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• 2012

A list of volatile fatty acids (VFA) including propionic acid, butyric acid, isovaleric acid, valeric acid, etc. is well known for offensive odorants. The analysis of odorant VFA is a highly delicate task due to high reactivity and unstable recovery rate. At present, analytical methods of VFA are recommended to include alkali impregnation filter method and alkali absorption method by the malodor prevention law of the Korea Ministry of Environment (KMOE). In this review, a survey has been made to explore various approaches available for the analysis of VFA to include both official methods of the KMOE and others. In light of the unreliability of those established analytical methods, it is highly desirable to develop some substituting methods for VFA. Among such options, one may consider such option as sorbent tube (ST) sampling and cryogenic trapping-thermal desorption technique. Moreover, procedures used for standard preparation, sampling steps, and instrumental detection stage are also evaluated. Application of container sampling (like Tedlar bag) is however not recommendable due to significant (sorptive) loss in sampling and in storage stage. In the detection stage, the use of GC/MS is recommendable to replace GC/FID due to the presence of diverse interfering substances. Thus, it is essential to properly establish the basic quality assurance (QA) for VFA analysis in air.

• Applied Biological Chemistry
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• v.11
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• pp.123-130
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• 1969

Five varieties of sweetpotatoes recommended in Korea were investigated with respect to the storing capacity, resin content and the possibility of developing sweetpotato chips as a new processed food item. The results are summarized as follows: 1) Two varieties, Suwon No. 147 and Chun-Mi were more resistant to chilling injury and soft-rot decay than other varieties. 2) The contents of resinous and polyphenolic substances were quite different depending upon the variety. 3) Sweetpotato chips of different color were made from different varieties and rapeseed oil was found to be the best as frying oil. 4) Best conditions to prepare sweetpotato chips with fresh color and proper texture were to dip slices of 1-2 mm thickness in 0.25% sodium bisulfite solution at $40^{\circ}C$ for 30-40 minutes and to subject to deep frying in an oil bath at $150-160^{\circ}C$ for 2.5 to 3.5 minutes. 5) Polyethylene-cellophane film as packing material of sweetpotato chips was the film in the moisture proof and film-impact tests.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.817-826
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• 2005

Recently it has been reported that vitamin A and retinol binding proteins (RBPs) in blood and urine were changed in the condition of diabetes mellitus or hyperlipidemia. Fruits and vegetables are recommended to consume for the people suffered from these chronic degenerative diseases. The main components of fruits and vegetables are dietary fibers, for example cellulose and pectin, of which function to affect the absorption and excretion of dietary fat and fat-soluble substances. This study was conducted to investigate the effect of dietary fibers on RBPs mRNA expression in liver, small intestine and serum of rat fed high fat diet during 4 weeks. Sprague-Dawley rats, weighing 121g on average, were divided into four groups; (Control; $17\%$ fat & cellulose supplement diet, HF0: $25\%$ fat & fiber free diet, B:.Uc: $25\%$ fat & cellulose supplement diet and HF0: $25\%$ fat & pectin supplement diet) . The rats fed high fat diet groups (HF0, HFC, HFP) tended to consume the food less than the control group, but FER of HF0 groups was significantly higher than the control (p < 0.05) . The weight of adrenal gland in high fat diet groups (HF0, HFC, HFP) was significantly less than the control. Total lipid in feces daily excreted and in liver did not show any significant differences among the groups. Total cholesterol in HFP group was significantly different from that of HFC group. Serum total cholesterol and triglyceride in other group tended to lower than other groups and HDL cholesterol higher. Consequently, AI (atherogenic index) was the lowest in HFP group. Vit A contents in feces daily excreted tended to lower in high fat diet groups (HF0, HFP) compared to the control group. That content in adrenal gland was the lowest in HF0 group, but not in liver. In HFP group were down-regulated cRBPI mRNA in liver and cRBPII mRNA in small intestine and up-regulated RBP and transthyretin expression in serum compared to the other groups. In conclusion, dietary fibers, especially pectin, in high fat diet might down-regulate the expression of CRBP I, CRBP II mRNA in liver and small intestine, but increase the secretion of RBP into serum and therefore inhance the bioavailability of Vit A through the body. (Korean J Nutrition 38(10): 817$\sim$826,2005)

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.398-409
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• 2021

Background: The types and effects of hazardous pollutants in indoor air may vary depending on the characteristics of the sources and pollutants caused by physical and chemical properties of buildings, the influence of outdoor air, and the exposure and use characteristics of residents. Objectives: This study was conducted to provide basic data on the establish of indoor air quality management for different classes of public-use facilities by presenting the characteristics of concentration distribution of hazardous pollutants by different public-use facilities and the status of the excess proportion of exceeding standards. Methods: This study analyzed self-measurement data from public-use facilities taken from 2017 to 2019 A total of 133,525 facilities were surveyed. A total of 10 types of pollutants that have maintenance and recommended standards stipulated in the Indoor Air Quality Control Act from the Ministry of Environment were investigated. The excess proportion and the substances exceeding the criteria for each type of public-use facilities for these pollutants were investigated. Results: As a result of the analysis of the proportion of exceeding the standard for each type of public-use facility, the facilities with the highest excess proportion of the standards for each hazardous pollutant were: PM₁₀ in railway stations (8.93%), PM_2.5 in daycare centers (7.36%), CO₂ in bus terminals (2.37%), HCHO in postpartum care centers (4.11%), total airborne bacteria in daycare centers (0.69%), CO in museums (0.1%), NO₂ in postpartum care centers (1.15%), Rn in museums (0.78%), total volatile organic compounds in postpartum care centers (7.20%) and mold in daycare centers (1.44%). Conclusions: Although uncertainty may arise because this study is a result of self-measurement, it is considered that this study has significance for providing basic data on the establishment in the future of indoor air quality management measures customized for each type of public-use facility.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.510-519
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• 2021

Volatile Organic Compounds (VOCs) in sediments, which can cause human health problems, have been monitored in Korea since 2014. Measured VOC concentrations can be affected by matrix type and the volatility of target substances. In this study, (1) VOCs volatility and the influence of matrix interference were confirmed, and (2) internal standards (IS) method was applied to improve analytical method. For these purposes, method detection limit (MDL), calibration linearity, precision and accuracy of VOCs were compared in various matrices using the IS. Some of VOCs in sediments showed different peak areas and reduced rates compared to water matrix. It was suggested that adsorption properties of sediments hindered the migration to vapor during heat pretreatment in headspace method. A calibration curve was created in clean sand. Recovery rates for the calibration curve method and IS applying method were 64.1~83.1% and 99.1~119.3%, respectively. Relative standard deviations ranged from 11.1% to 21.6% for the calibration curve method and those for IS ranged 4.7% to 13.7%. In case of real sediment, calibration curve and 1,2-Dichlorobenzene-d4 (ODCB) among IS were not suitable. The average recovery rate of Fluorobenzene (FBZ) increased by 56.4% and Relative Standard Deviation (RSD) by 4.7%. However, the recovery rate was increased in the samples with large values of igniting intensity. This study confirmed that influence of the matrix of VOCs in sediment, and addition of IS materials improved precision and accuracy. Although IS corrects volatilization and adsorption, it is recommended that more than two types of IS should be added rather than single.

• Food Science of Animal Resources
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• v.42 no.1
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• pp.153-174
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• 2022

This trial was conducted to evaluate the effect of overwrap, vacuum, and modified atmosphere packaging (MAP) on poultry breast fillets' microbiological, biochemical shelf life and sensory attributes. The fillets were divided into 4 groups, and each of the treatments was replicated 3 times with 60 breast fillets. The first group was a control group with overwrap packaging; the second group was vacuum packed (VP); the third and fourth groups were MAP-1: 0% O₂, 40% CO₂, 60% N₂, and MAP-2: 20% O₂, 40% CO₂, 40% N₂. The microbiological and biochemical analyses were performed for the total viable count, coliform count, Pseudomonas count, Salmonella count, total volatile basic nitrogen (TVB-N), pH, cooking loss, color, lipid oxidation, tenderness, and sensory analysis. The data were analysed through two-way ANOVA by Minitab (Minitab 17.3.1). Meat treated with understudy MAP compositions and vacuum packaging reduced total viable count, Pseudomonas count, and total coliform count than control (p<0.05). TVB-N remained below the recommended limit throughout storage except aerobic packaging (p<0.05). Cooking loss (%) was lowered and showed non-significant results (p>0.05) between vacuum packaging and both MAP concentrations. The meat stored in MAP-2 was characterised by higher (p<0.05) visual scores. Whilst MAP-1 showed higher (p<0.05) L^* values and overall acceptability. Sample packaged under aerobic packaging showed significant (p<0.05) results for b^* and thiobarbituric acid reactive substances (TBARS). Meat stored in aerobic packaging showed higher (p<0.05) shear force values. The outcome of this trial may help to promote the application of understudy MAP compositions and rapid detection of microbes by biochemical analysis under local conditions.

• Analytical Science and Technology
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• v.35 no.3
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• pp.93-115
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• 2022

Potential impurities in pharmaceuticals could be produced during manufacture, distribution, and storage and affect quality and safety of pharmaceuticals. In particular, highly reactive impurities could result in carcinogenic (mutagenic) effects on human body. International Conference on Harmonisation (ICH) has provided M7(R1) guideline for "Assessment and Control of DNA Reactive (Mutagenic) Impurities in Pharmaceuticals to Limit Potential Carcinogenic Risk" and recommended an adoption of this guideline to the authorities. ICH M7(R1) guideline provides classification, accepted intakes, and controls of potential impurities in pharmaceuticals. However, since appropriate and unified analytical methods for impurities in pharmaceuticals have not been provided in this guideline, most potential impurities in pharmaceuticals are still difficult to manage and supervise by pharmaceutical companies and regulatory authorities, respectively. In this review, we briefly described definition of unintended mutagenic impurities, basic information in ICH M7(R1) guideline, and analytical methods to determine potential impurities. This review would be helpful to manage and supervise potential impurities in pharmaceuticals by pharmaceutical companies and regulatory authorities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.86-97
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• 1988

Sesame(Sesamum indicum L.) is probably the most ancient oilseed crop known in the world. The seed of sesame is used in a variety of ways as food. The whole seed may be eaten raw, either roasted or parched, or fed to birds and stock. Sesame oil is used as a salad or cooking oil, in shortening, margarine and in the manufacture of soap. Minor uses are as a fixative in the perfume industry and formerly as a carrier for fatsoluble substances in pharmaceuticals such as penicillin. One of the minor constituents of sesame oil, sesamin, is used for its synergistic effect in pyrethrin insecticides, in addition of a small quantity of this substance markedly increases the effectiveness of fly sprays. The meal remaining after oil extraction can be used as and animal feed-stuff or as manure. In general sesame meal is considered to be equal to cottonseed or soybean meal as a protein supplement for livestock and poultry. It is especially high in certain amino-acids such as methionine, which is low in soybean meal, and thus can be combined with it or similar meal to form a more balanced ration. An attempt to summarize the literature review on quality improvement of sesame was made to discuss the accomplishments of the past and perspectives in the future. The reviews on quality improvement of sesame were mainly discussed in connection with the cultural practices and genetic informations in current status. The emphasis focussed on environmental variation of quality in cultural practices, such as harvest time, variety by location, climatic condition, fertilizer application, and growth regulator treatment. On the genetic variation of quality, it was discussed on variety background, mutation breeding, correlations, and inheritance of quality related characteristics. It also was discussed on relationship between quality and plant traits, storage condition or period, and seed coat color. Moreover, current research status were reviewed on some minor elements such as sesamin, oxalic acid, and trypsin inhibitor. As a results of the review, the lack of an effort to quality improvement in each utilization area was indicated as a problem area. More active efforts for the improvement of quality were also insufficient to incorporate the available genes for quality in breeding method or collection and analysis of breeding materials. Therefore, researches in the future would be recommended to emphasize on these problem areas.