• Journal of the Korean Electrochemical Society
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• v.24 no.4
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• pp.120-132
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• 2021

Although the development of high-Nickel is being actively carried out to solve the capacity limitation and the high price of raw cobalt due to the limitation of high voltage use of the existing LiCoO₂, the deterioration of the battery characteristics due to the decrease in structural stability and increase of the Ni content. It is an important cause of delaying commercialization. Therefore, in order to increase the high stability of the Ni-rich ternary cathod material LiNi_0.6Co_0.2Mn_0.2O₂, precursor Ni_0.6Co_0.2Mn_0.2-x(OH)₂/xTiO₂ was prepared using a nanosized TiO₂ suspension type source for uniform Ti substitution in the precursor. It was mixed with Li₂CO₃, and after heating, the cathode active material LiNi_0.6Co_0.2Mn_0.2-xTi_xO₂ was synthesized, and the physical properties according to the Ti content were compared. Through FE-SEM and EDS mapping analysis, it was confirmed that a positive electrode active material having a uniform particle size was prepared through Ti-substituted spherical precursor and Particle Size Analyzer and internal density and strength were increased, XRD structure analysis and ICP-MS quantitative analysis confirmed that the capacity was effectively maintained even when the Ti-substituted positive electrode active material was manufactured and charging and discharging were continued at high temperature and high voltage.

• Korean Journal of Plant Resources
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• v.35 no.4
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• pp.435-444
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• 2022

Hibiscus hamabo Sieb. et Zucc. (yellow hibiscus) is a deciduous semi-shrub plant and mainly growing in Jeju Island. This is known the unique wild hibiscus genus and classified as an 2nd grade of endangered plant for Korean Red List. In previous studies, properties of germination, ecological, genetical and salt resistance have been reported. In this study, we investigated mass-proliferated adventitious root using bioreactor, antioxidant and whitening effects to conduct functional ingredients. Yellow hibiscus were collected from Gujwa, Jeju by prior permission and they were introduced by explant type and various medium composition after surface sterilization. As a result, seed response rates were evaluated at range of 51.17~51.83%, in terms of comprehensive efficiency of shoot and root formation. In the case of adventitious root propagation condition was confirmed in half strength Murashige and Skoog medium salts, 30 mg/L sucrose, and 2 mg/L indole-3-butyric acid for 8 weeks in 5,000 mL bioreactor. We also compared between relationship with biomass and secondary metabolites accumulation by total phenolics content, the flavonoid content, DPPH free radical scavenging activity and melanin content. The results indicated that adventitious root mass proliferation, antioxidant and whitening effect could develop value of the high-quality cosmeceutical ingredient and further metabolite studies.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.2
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• pp.1-19
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• 2023

In Korea, excessive vegetation in rivers made up of sand and gravel is emerging as a nationwide problem, which is attributed to increased spring precipitation and decreased annual precipitation. Therefore, this study was conducted for the purpose of identifying the effect of changes in precipitation patterns on river vegetation in Namcheon, Gyeongju, and analyzing the area of vegetation and ecological characteristics. As a result of the study, the amount of monthly precipitation in the summer of Namcheon decreased after 2007, and the area of vegetation increased continuously compared to the area of the sandbank. The proportion of naturalized plants increased steadily when precipitation continued to a level that did not cause flooding, but the area occupied by naturalized plants was small. Also, when the water level is maintained, the species diversity is low due to the dominance of a single species, and the dominant species was mainly native plants. Dominance of native plants inhibited the growth of naturalized plants, but the vegetation area increased even more. Therefore, it is necessary to manage the spread of vegetation itself rather than the division of native plants and naturalized plants in order to eliminate the active growth and prosperity of river vegetation. High water levels and continuous flooding caused by torrential rains in summer disturbed the plant communities, and vegetation formed afterwards was mainly native plants. Such flooding in river ecosystems is a positive factor for the emergence of native plants and over-formed vegetation communities, so it should be considered when establishing a vegetation management plan.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.17-27
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• 2022

In this study, we evaluated the antioxidant and antidiabetic effects of buckwheat. The diabetic animal models were divided into four groups: normal mice group (NOR), streptozotocin-induced diabetic mice group (STZ), group treated with seeds of common or tartary buckwheat (SCB or STB), and the group treated with whole plants of common or tartary buckwheat (PCB or PTB). Rutin content was 44-48 times higher in STB or PTB than in SCB. Oral glucose tolerance and insulin resistance were significantly reduced by treatment with STB, PCB, and PTB. Treatment with PTB also decreased the serum glucose level significantly and the serum insulin levels slightly compared with the STZ group. These results suggest that rutin content and antioxidant activity are closely related to the antidiabetic effect of the treatment. Our results demonstrate that the seeds of tartary buckwheat and whole plants of either common or tartary buckwheat have antidiabetic effects-attenuating blood glucose in an animal model of type II diabetes.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.435-445
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• 2023

The aim of this study was to explore the effects of vinegar extract from seed of common buckwheat (Fagopyrum esculentum Moench) and seed of tartary buckwheat (F. tataricum Gaertner) on acute ethanol-induced hangover in Sprague-Dawley rats. Vinegar extract from buckwheat is rich choline, quercetin and its glycoside, rutin known as flavonoid antioxidants. The test extract containing buckwheat was proven to alleviate hangovers through a significant reduction in the concentration of alcohol and acetaldehyde in the context of an alcohol-induced hangover model. Hepatic alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activities were significantly higher in buckwheat vinegar-treated rats than in ethanol-treated rats. Moreover, tartary buckwheat vinegar upregulated antioxidant enzyme such as superoxide dismutase and Catalase activities in liver tissues. These results suggest that buckwheat vinegar extract could alleviate ethanol-induced hangover symptoms by elevating activities related to hepatic ethanol-metabolizing enzymes against ethanol induced metabolites, and in particular, tartary buckwheat should be further developed to be a novel anti-hangover material.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.455-468
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• 2023

We aimed to assess the potential growth-promoting effects of buckwheat sprout on intestinal bacteria and their anti-inflammation effects in a cellular model of intestinal inflammation. The growth of Bifidobacterium longum ssp. infantis BT1 was enhanced with the addition of the sprout extract of tartary buckwheat. Further, in the inflammatory model cells cultured with Raw 264.7 cells were treated with buckwheat sprout including each 10 probiotics before the addition of lipopolysaccharide (LPS) to induce inflammation in Raw 264.7 cells. Buckwheat sprout in both Bifidobacterium longum ssp. infantis BT1 and Lacticaseibacillus paracasei LPC5 significantly reduced the production of NO and PGE₂. The above results indicate that buckwheat sprout extract which contains with various physiologically active substances such as rutin, quercetin, and choline is effective in suppressing NO and PGE₂ production, which are inflammation-related indicators. The present study suggests that buckwheat sprout could induce positive effects on the intestinal beneficial bacteria and in anti-inflammation.

• Journal of Life Science
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• v.34 no.1
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• pp.18-27
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• 2024

Laying hens are known to be able to 'bio-accumulate' the health-promoting ingredients of their diet into eggs. The purpose of this study was to characterize lignan-rich eggs as functional food fed with Schisandra fruit by-product (SCP). Experimental diets were formulated using yellow corn, rice bran, soybean meal, fish meal, meat bone meal, poultry meal, vitamin premix, mineral premix, CaCO₃, and supplemented Schisandra chinensis by-product. This experiment conducted a completely randomized design with 5 treatments for 5 laying hens. Levels of SCP were fed control diet or each formulated diet containing 1%, 3%, 5% and 7% SCP powder. The weight of eggs and the lignan content in white and yolk of egg were investigated every 7 days. Egg production and egg weight were not affected by diet at less than 5% SCP in the diet, but were significantly reduced when the diet was supplemented with a high concentration of 7% SCP after 3 weeks. Yolks and white in eggs were analyzed by using a high performance liquid chromatography (HPLC) to determine the lignans profile. Higher dietary SCP supplementation significantly increased gomisin N and schisandrin C in Acetonitrile (p<0.05). Gomisin N in egg white increased in a concentration-dependent manner, but shisandrin C not detected. These results indicated that the use of SCP powder in layering diets was effective in egg quality and for the production of lignans fortified eggs. In conclusion, dietary supplementation of Schisandra by-product with less than 5% can produce lignans-enrich eggs used as functional foods.

• Journal of Preventive Medicine and Public Health
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• v.25 no.2 s.38
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• pp.127-140
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• 1992

This study was done to identify the association between serum copper and zinc levels and the cirrhosis and hepatocellular carcinoma(HCC), and to evaluate its diagnostic value on liver diseases. Sixty-three healthy persons, 60 patients with cirrhosis and 33 patients with hepatocellular carcinoma were rendomly selected and investigated for their general characteristics from October 1990 to August 1991. For analysis of the biochemical markers in liver function test and the serum copper and zinc levels, their fasting venous blood were sampled at 9:00 to 11:00 in the morning and centrifuged to separate the serum within one hour. All the samples were immediately analysed for biochemical markers and stored at $-20^{\circ}C$ in polypropylene tubes further copper and zinc analysis. Mean of serum coppper levels was $91.97{\pm}4.76{\mu}g/dl$ in control, $106.21{\pm}2.73{\mu}g/dl$ in cirrhosis and $127.05{\pm}0.77{\mu}g/dl$ in HCC. The value of HCC was statistically significantly higher than that of the control and cirrhosis(p<0.05). Serum zinc levels were $110.82{\pm}7.24{\mu}g/dl$ in control, $68.10{\pm}5.43{\mu}g/dl$ in cirrhosis and $63.78{\pm}2.20{\mu}g/dl$ in HCC. The values of cirrhosis and HCC were statistically significantly lower than that of control(p<0.05). The Cu/Zn ratio was statiatically significantly different among three groups(p<0.05). Test total protein, albumin, ALP and total bilirubin of biochemical markers of liver function were statistically significantly different among three groups(p<0.05). Differences between cirrhosis and HCC for ALT and AST, and between the control and HCC for direct bilirubin were not statistically significant. Biochemical markers statistically significantly correlated with serum copper and zinc levels and Cu/Zn ratio(p<0.05), were variable in three groups. In multiple logistic regression, odds ratio of serum copper level and Cu/Zn ratio had no statistical significance on the cirrhosis and the HCC, but that of serum sinc was statistically significant as 0.951 and 0.952(p<0.05). Serum copper and zinc levels and Cu/Zn ratio were not statistically significantly different between the cirrhosis and HCC. H\Albumin, ALP, zinc, total bilirubin and age among all variables were selected as main variables for three-group discriminant analysis. Percentage of 'grouped' cases correctly classified by these five variables was 98.4 for control, 73.4 for cirrhosis, 75.7 for HCC and 84.0 for all subjects. This study suggests that zinc level is considered to play a role as diagnostic marker on the hepatic disorders and be more useful than serum copper level and Cu/Zn ratio in diagnosis of the liver diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1895-1904
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• 2015

Foodborne illness associated with food service establishments is an important food safety issue in Korea. In this study, foodborne pathogens (Bacillus cereus, Clostridium perfringens, Escherichia coli, pathogenic Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Vibrio parahaemolyticus) and hygiene indicator organisms [total viable cell counts (TVC), coliforms] were analyzed for food and environmental samples from foodservice establishments at schools in Gyeonggi province. Virulence factors and antimicrobial resistance of detected foodborne pathogens were also characterized. A total of 179 samples, including food (n=66), utensil (n=68), and environmental samples (n=45), were collected from eight food service establishments at schools in Gyeonggi province. Average contamination levels of TVC for foods (including raw materials) and environmental samples were 4.7 and 4.0 log CFU/g, respectively. Average contamination levels of coliforms were 2.7 and 4.0 log CFU/g for foods and environmental swab samples, respectively. B. cereus contamination was detected in food samples with an average of 2.1 log CFU/g. E. coli was detected only in raw materials, and S. aureus was positive in raw materials as well as environmental swab samples. Other foodborne pathogens were not detected in all samples. The entire B. cereus isolates possessed at least one of the diarrheal toxin genes (hblACD, nheABC, entFM, and cytK enterotoxin gene). However, ces gene encoding emetic toxin was not detected in B. cereus isolates. S. aureus isolates (n=16) contained at least one or more of the tested enterotoxin genes, except for tst gene. For E. coli and S. aureus, 92.7% and 37.5% of the isolates were susceptible against 16 and 19 antimicrobials, respectively. The analyzed microbial hazards could provide useful information for quantitative microbial risk assessment and food safety management system to control foodborne illness outbreaks in food service establishments.