• Journal of Life Science
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• v.29 no.6
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• pp.688-696
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• 2019

This study investigated changes in triglyceride and cholesterol synthesis and tyrosinase activity induced by ice plant (Mesembryanthemum crystallinum L.) extract, which cannot be stored for long periods of time due to its high moisture content when it was fermented to improve its storage stability. The accumulation of triglyceride and cholesterol in HepG2 cells inhibited the accumulation with a relatively large magnitude in n-butanol and aqueous fractions that generally have high polarity, however, changes in inhibition potency due to the fermentation were not significant. As for the effect to inhibit tyrosinase activity, when L-tyrosine was used as a substrate, the inhibitory activity was the highest for the aqueous fraction at $60.58{\pm}4.03%$ and $63.35{\pm}4.35%$, before and after fermentation, respectively, which amounted to 72% of that of the positive control group (arbutin, $100{\mu}g/ml$). In addition, when L-3,4-dihydroxyphenylalanine (L-DOPA) was used as a substrate, the inhibitory activity was also found the highest for the aqueous fraction at $56.85{\pm}1.57%$ and $59.38{\pm}1.74%$, before and after fermentation, respectively, which amounted to at least 88% of that in the positive control (kojic acid, $100{\mu}g/ml$). Overall, the activity of the fermented ice plant extract was similar or a little higher compared to that of the one without fermentation, indicating that fermentation can be a good approach to improve the storage stability of the ice plant.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.83-91
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• 2019

The purpose of this study is to assess a fire-damaged concrete structure using a digital camera and image processing software. To simulate it, mortar and paste samples of W/C=0.5(general strength) and 0.3(high strength) were put into an electric furnace and simulated from $100^{\circ}C$ to $1000^{\circ}C$. Here, the paste was processed into a powder to measure CIELAB chromaticity, and the samples were taken with a digital camera. The RGB chromaticity was measured by color intensity analyzer software. As a result, the residual compressive strength of W/C=0.5 and 0.3 was 87.2 % and 86.7 % at the heating temperature of $400^{\circ}C$. However there was a sudden decrease in strength at the temperature above $500^{\circ}C$, while the residual compressive strength of W/C=0.5 and 0.3 was 55.2 % and 51.9 % of residual strength. At the temperature $700^{\circ}C$ or higher, W/C=0.5 and W/C=0.3 show 26.3% and 27.8% of residual strength, so that the durability of the structure could not be secured. The results of $L^*a^*b$ color analysis show that $b^*$ increases rapidly after $700^{\circ}C$. It is analyzed that the intensity of yellow becomes strong after $700^{\circ}C$. Further, the RGB analysis found that the histogram kurtosis and frequency of Red and Green increases after $700^{\circ}C$. It is analyzed that number of Red and Green pixels are increased. Therefore, it is deemed possible to estimate the degree of damage by checking the change in yellow($b^*$ or R+G) when analyzing the chromaticity of the fire-damaged concrete structures.

• Journal of Nutrition and Health
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• v.52 no.5
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• pp.501-513
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• 2019

Purpose: This study examined the menu pattern, food diversity, and satisfaction of parents with the snack menus of childcare centers provided by the Center for Children's Foodservice Management (CCFM) in Jeonbuk area. Methods: Data from 2,432 snack menus (1,321 for morning snacks and 1,111 for afternoon snacks) of March, June, September, and December 2017 from 13 CCFM in Jeonbuk area were analyzed. In addition, the participants for the survey were 247 parents in Jeonju and Kunsan. The data were analyzed using a t-test, ${\chi}^2$-test, and hierarchical regression analysis with SPSS v. 24.0. Results: Differences in the menu pattern and food diversity were observed between morning and afternoon snack menus. The majority of snack menus (61.6%) were one menu item. The percentage of 'G' (20.0%) was highest in the food group patterns. The morning snacks served mainly porridge, raw fruits, and milk, and the afternoon snacks served mainly flour-based foods, juices, and milk. The awareness level of parents about the snack menus of daycare centers was $4.09{\pm}0.82$, and its overall satisfaction was $4.06{\pm}0.69$. In the snack-quality attribute analysis, the hygiene of foods was the most important factor, and parents judged that they were doing well. Regression analysis showed that the hygiene of personnel was the most influential variable on the overall satisfaction, followed by balance with the main meal and the portion size. Conclusion: Therefore, it is important to establish snack menu guidelines considering the eating behaviors of the children and to strengthen hygiene for the increasing the satisfaction of various stakeholders in daycare centers.

• Journal of Korean Home Economics Education Association
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• v.33 no.1
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• pp.63-79
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• 2021

This study examined yearly trend of sugar-sweetened beverage(SSB) intake and compared nutritional status by SSB intake level in middle school students aged 12~14 years(n=2,543) using the data from 2007~2015 Korea National Health and Nutrition Examination Survey. SSB included carbonated drinks, sports drinks, and caffeinated drinks contained added sugar. Subjects were classified into three groups by SSB intake level obtained from 24-hour recall method: SSB 1(SSB intake 0 g/d), SSB 2(0 g/d < SSB intake < 50th percentile) and SSB 3(SSB intake ≥ 50th percentile). Result of daily intake of SSB was 76.1±6.2 g/d for boys and 59.5±4.7 g/d for girls and it was increased significantly for boys(p-trend 0.0004) and girls(p-trend 0.0038) by year. The most intakes were carbonated drinks followed by fruit juices and sports drinks for boys and girls. Percentage of daily intake compared to the dietary reference was increased for energy and iron while was decreased for calcium and vitamin C toward SSB 3 group. Ratio of excess intake of energy/fat was increased significantly for boys(p=0.0091) and girls(p<0.0001) toward SSB 3 group. Ratio of calcium deficiency was 86.8~94.9% for boys and girls and it was very high. Therefore, it should be emphasized to reduce SSB intake and drink plain water without added sugar, etc. and milk as a source of calcium for improving nutritional status of middle school students through dietary education and social support.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.97-106
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• 2022

Listeria monocytogenes (L. monocytogenes) is one of gram-positive foodborne pathogens with a very high fatality rate. Unlike most foodborne pathogens, L. monocytogenes is capable of growing at low temperatures, such as in refrigerated foods. Thus, various physical and chemical prevention methods are used in the manufacturing, processing and distribution of food. However, there are limitations to the methods such as possible changes to the food quality and the consumer awareness of synthetic preservatives. Thus, the aim of this study was to evaluate the anti-listeria activity of lactic acid bacteria (LAB) isolated from kimchi and characterize the bacteriocin produced by Lactococcuslactis which is one of isolated strains from kimchi. The analysis on the anti-listeria activity of a total of 36 species (Lactobacillus, Weissella, Lactobacillus, and Lactococcus) isolated from kimchi by the agar overlay method revealed that L. lactis NJ 1-10 and NJ 1-16 had the highest anti-listeria activity. For quantitatively analysis on the anti-listeria activity, NJ 1-10 and NJ 1-16 were co-cultured with L. monocytogenes in Brain Heat Infusion (BHI) broth, respectively. As a result, L. monocytogenes was reduced by 3.0 log CFU/mL in 20 h, lowering the number of bacteria to below the detection limit. Both LAB strains showed anti-listeria activity against 24 serotypes of L. monocytogenes, although the sizes of clear zone was slightly different. No clear zone was observed when the supernatants of both LAB cultures were treated with proteinase-K, indicating that their anti-listerial activities might be due to the production of bacteriocins. Heat stability of the partially purified bacteriocins of NJ 1-10 and NJ 1-16 was relatively stable at 60℃ and 80℃. Yet, their anti-listeria activities were completely lost by 60 min of treatment at 100℃ and 15 min of treatment at 121℃. The analysis on the pH stability showed that their anti-listeria activities were the most stable at pH 4.01, and decreased with the increasing pH value, yet, was not completely lost. Partially purified bacteriocins showed relatively stable anti-listeria activities in acetone, ethanol, and methanol, but their activities were reduced after chloroform treatment, yet was not completely lost. Conclusively, this study revealed that the bacteriocins produced by NJ 1-10 and NJ 1-16 effectively reduced L. monocytogenes, and that they were relatively stable against heat, pH, and organic solvents, therefore implying their potential as a natural antibacterial substance for controlling L. monocytogenes in food.

• Resources Recycling
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• v.32 no.1
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• pp.50-59
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• 2023

The amount of dust generated during the dissolution of scrap in an electric arc furnace is approximately 1.5% of the scrap metal input, and it is primarily collected in a bag filter. Electric arc furnace dust primarily consists of zinc and ion. The processing of zinc starts with its conversion into pellet form by the addition of a carbon-based reducing agent(coke, anthracite) and limestone (C/S control). These pellets then undergo reduction, volatilization, and re-oxidation in rotary kiln or RHF reactor to recover crude zinc oxide (60%w/w). Next, iron is discharged from the electric arc furnace dust as a solid called Fe clinker (secondary by-product of the Fe-base). Several methods are then used to treat the Fe clinker, which vary depending on the country, including landfilling and recycling (e.g., subbase course material, aggregate for concrete, Fe-source for cement manufacturing). However, landfilling has several drawbacks, including environmental pollution due to leaching, high landfill costs, and wastage of iron resources. To improve Fe recovery in the clinker, we pulverized it into optimal -sized particles and employed specific gravity and magnetic force selection methods to isolate this metal. A carbon-based reducing agent and a binding material were added to the separated coarse powder (>10㎛) to prepare briquette clinker. A small amount (1-3%w/w) of the briquette clinker was charged with the scrap in an electric arc furnace to evaluate its feasibility as an additives (carbonaceous material, heat-generating material, and Fe source).

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.138-164
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• 2022

The Neolithic shell midden in Daejuk-ri, Seosan, is distributed on the gentle slope of a low hill close to the west coast. The bedrock of the area consists mainly of schist with various mafic minerals, but shows a partial gneiss pattern. The site consists of loamy topsoil and clay loam subsoil, and the degree of siallization is relatively low. Although the pottery excavated from the shell midden shares mostly similar features, a variety of shapes and patterns coexist. The surface colors, thickness and physical properties are slightly different. The pottery can be subdivided into three types (IA, IB and II) according to the composition of the body clay, the temper and the existence of a black core. Types IA and IB are colorless mineral pottery with a non-black or black core respectively. TypeII is colored mineral pottery with a non-black core. Type I pottery also contains non-plastic colored minerals, but type II contains a large amount of biotite, chlorite, talc, amphibole, diopside and tremolite, which include a large amount of Mg and Fe. The studied pottery contains a small amount of organic matter. Considering the grain size and relatively poor sorting and roundness of the non-plastic particles, the pottery appears to be made by adding coarse non-plastic tempers for special purposes to the untreated weathered soil around the site. The three types of pottery seem to have been incompletely fired in general. While type IB has the lowest degree of oxidation, typeII shows the highest degree of redness and oxidation. It can be interpreted that these differences depend on the firing temperature and the ratio of non-plastic particles. Through a synthesis of the minerals, geochemical data and thermal history, it can be determined that the firing temperature ranged from 600 to 700℃. The pottery types of the Daejuk-ri Shell Midden have slightly different production conditions, mineral compositions, and physical properties, but have undergone similar production processes with basically the same clay materials. The clay is almost identical to the composition of the bedrock and weathered soil distributed in the Daejuk-ri area. Currently, there is an industrial complex in the area, so it is difficult to confirm the soil and geological distribution of the site. However, it is highly probable that the area around the site was self-sufficient for the clay and tempers required for the production of the Neolithic pottery. Therefore, it can be interpreted that the group that left the shell midden in Daejuk-ri lived near the site, visited the site for the purpose of collecting and processing shellfish, and discarded the broken pottery along with shells.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.475-481
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• 2019

The soybean cultivar 'Neulchan' was developed for production of soy-paste and tofu. SS91501-9-1-1 and SS96205 (F₂) were crossed in 1998, and F₃ to F₇ were selected by the pedigree method. A preliminary yield trial (PYT) and an advanced yield trial (AYT) were conducted from 2006 to 2008, and a regional yield trial (RYT) in nine regions was conducted from 2009 to 2011. In the RYT, 'Neulchan' was stable in variable environments and generated high yield. 'Neulchan' was determinate with white flower, light brown pod color, yellow spherical seed, and yellow hilum. Its flowering date and maturity date were Jul. 30 and Oct. 9, respectively. The plant height was shorter than that of 'Daewonkong' (a standard cultivar). 'Neulchan' had the same node number (14), higher first-pod height (12 cm), and lighter seed weight (21.7 g/100-seed weight) than those of 'Daewonkong' (14, 11, and 24.2 g/100-seed weight, respectively). 'Neulchan' had high resistance to bacterial pustule, and its resistance to soybean mosaic virus was similar to that of 'Daewonkong'. The yield and color of 'Neulchan' tofu were similar to those of 'Daewonkong' tofu, but the hardness was lower than that of 'Daewonkong' tofu. The soybean malt scent, fermented soybean yield, and γ-polyglutamic acid (γ-PGA) of 'Neulchan' were 3, 215%, and 24.6 mg/g, respectively. Its yield in adaptable regions was 307 kg/10a, higher than that of 'Daewonkong'. 'Neulchan' was expected to be cultivated and used widely for soy-paste and tofu production. (Registration No. 4904).

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.163-170
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• 2024

Red ginseng is manufactured as a health-functional food and is also present in various food types and in different product forms. However, there is currently no standardized regulation of ginsenoside content in foods containing red ginseng. In the present study, we analyzed the ginsenoside content of 66 red ginseng-containing foods and 35 health-functional foods collected online and directly from the market. The ginsenoside content was assessed using liquid chromatography (LC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. The ginsenoside content of the various food types ranged 0.0 (not detected)-71.567 mg per daily intake of foods containing red ginseng. Sugar-preserved foods had the highest ginsenoside content, followed by solid teas, liquid teas, and red ginseng beverages. For health-functional foods, the ginsenoside content ranged 3.4-58.5 mg per daily intake, with levels ranging 83-607% of the indicated amounts. All values met the established standards. Upon comparing red ginseng health-functional foods and red ginseng-containing foods, the average ginsenoside content was determined to be 18.21 and 8.79 mg, respectively, thus being nearly twice as high in health-functional foods. However, there was a minimal difference between the ginsenoside content of red and black ginseng, with values of 11.84 and 12.63 mg, respectively. These findings provide insights on the variations in ginsenoside content of red and black ginseng in various food forms. This information is expected to be valuable for future regulations and consumer choice of products containing red ginseng.

• Journal of Plant Biotechnology
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• v.50
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• pp.275-289
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• 2023

Since the implementation of the Living Modified Organisms (LMOs) Act in 2008, approximately 10 million tons of genetically modified corn, soybean, potato, canola, and other crops have been imported into South Korea. The import approval procedures have been completed for approximately 191 cases that include seven crops. Of these, approximately 90 cases, excluding crossbreeds of approved LMOs, were reviewed via consultation risk evaluation in four areas: human health, crop culture, natural ecology, and marine fishery environment. LMO developers in South Korea, who are major stakeholders in the import of LMO crops produced overseas, have raised concerns regarding procedural inefficiency in consultation reviews and the need of excessive reviews that are unsuitable for food-feed processing purposes. These procedures reflect the perspective of consultation agencies that deviate from the nature of risk assessment and demand specific supplementary data that do not reflect familiarity and substantial equilibrium. Based on frequent instances of unintentional environmental release of LMO crops imported into Korea, the ministries responsible for consultation insist on a review that considers the climate and natural environment of Korea. In addition, the ministries mandate that their reviews reflect the expertise of competent ministries and are based on risk assessment principles and methods in accordance with international guidelines. In this regard, considering that traits introduced into LMO crops involving familiar agricultural crops have been considered safe for more than two decades, we have suggested reasonable alternatives to several risk assessment items for agricultural LMOs. These alternatives can mitigate conflicts of interest among key stakeholders within the scope of the current LMO regulations.