• Asia-Pacific Journal of Business
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• v.15 no.1
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• pp.273-287
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• 2024

Purpose - This study conducts the co-occurrence analysis, one of the social network analysis using global OTA's online reviews and grades in order to understand the experience structure of foreign tourists visiting cutural tourism resources in Jeju, Korea. Design/methodology/approach - For this purpose, this study selects 6 cultural tourism resources in Jeju as the study sites, and collects qualitative review data (noun, adjectives, and verb) and quantitative grade data. Findings - The co-occurrence network analysis between words and grade of market and street shows that the grade of 5 appears the most simultaneous with pork, buy, lot, try, fresh, black, food, price, seafood, local, market, good, street, etc. and the grade of 1 connects with small, dish, better, taste, etc. And the co-occurrence network analysis between words and grade of tradition and folklore shows that the grade of 5 appears the most simultaneous with village, place, museum, visit, time, life, culture, women, diver, use, lot, etc. and the grade of 1 connects with minute, spend, room, recommend, honey, etc. Research implications or originality - The above research results are relevant in order to find out the core experience of foreign tourists using online review and grade generated by foreign tourists and use as the important information to develop the strategies related to the planning and management of cultural tourism resources.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.412-419
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• 2004

To investigate the utilization of calcium lactates (CaL) as coagulants for tofu manufacture, the quality characteristics and shelf-life of tofu made by CaL-P (black snail powder) and CaL-A (black snail ash) were investigated and compared to calcium chloride (CC), magnesium chloride (MC), calcium sulfate (CS ) and standard calcium lactate (CaL-S). And also, total microbe and turbidity of the tofu were determined during storage at 1$0^{\circ}C$. Coagulation ability of CaL-A was the highest, and the ability of CaL-P was higher than that of CaL-S. Yield of CaL-A tofu was similar to those of CS and CC tofu, while the yield of CaL-P tofu was 50% compared to that of CC. L＊ value of CaL-P tofu was lower, but a＊ and b＊ values were higher than those of other tofus. The hardness of tofu showed in the order of CaL-S>CS>CC>CaL-P>MC>CaL-A, while the cohesiveness showed in the order of MC>CaL-S>CC>CS>CaL-P>CaL-A. Calcium contents were 57 mg% in MC tofu, 174 mg% in CS tofu, 116 mg% in CaL-S tofu, 95 mg% in CaL-A tofu and 172 mg% in CaL-P tofu. From the results of microscopic observations, the lower hardness showed the more soft and the smaller particle. The particle of CaL-A tofu was small and uniformity but the size of CaL-P and CC tofu showed coarse. Sensory quality of CaL-P and -A tofu were better than the other tofu evaluated by texture, springiness, flavor and overall taste. The shelf-life estimated by total microbe was 4∼6 days in CC, MC, CS, CaL-S and CaL-A tofu, but 8 days in CaL-P tofu at 1$0^{\circ}C$. From the above results, the CaL-P and -A may believe to use as coagulant for tofu manufacture due to its softened taste and enhanced shelf-life, and higher calcium content which has higher absorbability in human body.

• Journal of Food Hygiene and Safety
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• v.31 no.2
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• pp.132-139
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• 2016

The purpose of this study was to investigate the contents of antioxidant compounds and antioxidant activities in teas. A total of 99 teas were tested for their antioxidant activities based on their ability to scavenge DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical. Antioxidant activity was expressed as mg of ascorbic acid equivalents per 100 g tea sample (L-ascorbic acid equivalent antioxidant capacity, AEAC) and was expressed as mg per 1 serving size (free radical scavenging activity, $FSC_{50}$). The total polyphenol contents of the extracts was quantified using the Folin-Ciocalteu method and the total flavonoid contents of the extracts was determined using a modied method of Davis. Vitamin C was analyzed by HPLC method. According to the AEAC value, mate tea, green tea, black tea, oriental raisin tea, chamomile tea and burdock tea showed relatively high antioxidant activities. Polyphenolic compounds were the major naturally occurring antioxidant compounds found in teas and the high concentrations of total polyphenol compounds were observed in black tea, green tea and mate tea. The high concentrations of total flavonoid compounds were observed in mate tea, black tea and yam tea and the amount of vitamin C contents were found to be high in citron tea and green tea. As a result, steeping tea was much higher in antioxidant activity than either powdered tea or liquefied tea. According to the study, a high correlation was demonstrated between the total polyphenol contents and antioxidant activities in teas (r = 0.846) and correlations between the total flavonoid contents and antioxidant activities was statistically significant in teas (r = 0.625). It was found that also the proportional relationship established among the total polyphenol content and antioxidant activities. That is, antioxidant activity of teas has been confirmed to have been caused by the total polyphenol.

• Journal of Life Science
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• v.28 no.4
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• pp.454-464
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• 2018

Black soybeans are used as food sources as well as for traditional medicines because they contain an abundance of natural phenolic compounds. In this study, total phenolic contents (TPCs) of Korean black seed coat soybean varieties Socheongja (SCJ), Socheong 2 (SC2) and Cheongja 2 (CJ2) as well as their antioxidant capacities were investigated. Among them, TPCs were abundantly present in the order of CJ2$H_2O_2$-stimulated HaCaT human keratinocytes. Our results revealed that treatment with SCJ and SC2 prior to $H_2O_2$ exposure significantly increases the viability of HaCaT cells, indicating that the exposure of HaCaT cells to SCJ and SC2 conferred a protective effect against oxidative stress. SCJ and SC2 also effectively inhibited $H_2O_2$-induced apoptotic cell death through the blocking of mitochondrial dysfunction. SCJ and SC2 also attenuated the phosphorylation of Histone H2AX. Furthermore, they effectively induced the levels of thioredoxin reductase (TrxR) 1, a potent antioxidant enzyme, which is associated with the induction of nuclear transcription factor erythroid-2-like factor 2 (Nrf2); however, the protective effects of SCJ and SC2 were significantly reversed by Auranofin, a TrxR inhibitor. These results indicate that they have protective activity through the blocking of cellular damage related to oxidative stress via the Nrf2 signaling pathway. In conclusion, our study indicated that SCJ and SC2 might potentially serve as novel agents for the treatment and prevention of skin disorders caused by oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1214-1220
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• 2016

This study compared antioxidant compounds and antioxidant activities according to various varieties of 18 colored rice. Selected rice cultivars for this study were as follows: black rice (12 cultivars)-Heugjinjubyeo, Nunkeunheugchal, Joeunheugmi, Josaengheugchal, Heuggwang, Heugseol, Shinmyeongheugchal, Shinongheugchal, Shintoheugmi, Cheongpungheukchal, Heughyang, Boseogheugchal, red rice (four cultivars)-Jeogjinju, Jeogjinjuchal, Hongjinju, Geonganghongmi, and green rice (two cultivars)-Nogwonchal and Jungmo1020. These were transplanted on June 30th and cultivated from the Department of Southern Area Crop Science, National Institute of Crop Science in Miryang, Korea. Total polyphenol (TP) content of black rice cultivars was higher than that of red rice varieties. Heugjinjubyeo exhibited the highest TP, which was $9.55{\pm}0.05mg$ gallic acid equivalent/g sample. There were no significant differences between black rice cultivars and red rice cultivars in terms of total flavonoid (TF) level. Heugjinjubyeo and Hongjinju showed the higher TF content than any other variety. Shintoheugmi revealed the highest anthocyanin content ($194.26{\pm}0.65mg/100g$). Methanol extract of Heugjinjubyeo had the highest antioxidant activities. 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities of Heugjinjubyeo extract were $14.70{\pm}0.62$ and $30.68{\pm}2.22{\mu}g/mL$, respectively. There were significant correlations between antioxidant compound content and antioxidant activities.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.538-552
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• 2017

In this study, total mercury (THg) of Black-tailed Gull (Larus crassirostris) eggs laid on Baengnyeongdo, West Sea of Korea was analyzed in order to compare the THg concentrations of eggs depending on egg-laying order. The first-laid eggs ($mean{\pm}standard$ error, $234.4{\pm}11.2ng/g\;wet$, n=18, t=8.4, p<0.01) significantly had higher THg concentrations than the second-laid eggs ($182.8{\pm}9.1ng/g\;wet$, n=18). Also, the first-laid eggs had higher values in biometrics (length $63.10{\pm}0.49mm$, t=2.4, p<0.05; width $44.51{\pm}0.19mm$, t=4.3, p<0.01; weight $65.53{\pm}0.87g$, t=4.2, p<0.01) than the second-laid eggs (length $62.37{\pm}0.40mm$, width $43.55{\pm}0.17mm$, and weight $62.48{\pm}0.72g$). These differences might be attributed to the amount of food eaten by females relating to males' courtship feeding pattern (males increase courtship feeding rate before the first eggs are laid, and decrease the rate following the laying of the first eggs). Moreover, the lower food intake of females could diminish the quantities of egg albumen that contains a protein binds to most of methylmercury during the period of egg production. Therefore, it is necessary to consistently apply one of egg selection methods (targeted selection (the first-laid egg or the second-laid egg), random selection, and etc.) in one nest for ensuring comparability of mercury concentrations among monitoring sites and monitoring years.

• Journal of Life Science
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• v.23 no.3
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• pp.432-442
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• 2013

In this study, we examined the biological activity and synergistic effects of an extract powder of 1% and 3%, each fresh (FGP) and black garlic (BGP) in streptozotocin-induced diabetic rats. Blood glucose content was significantly lower in FGP and BGP groups than control group. Glycosylated Hb was significantly higher in streptozotocin induced diabetic control group than normal group, but significantly lower in FGP and BGP groups. Total cholesterol content of the FGP and BGP groups were lower than control group, but not shown the significant difference between garlic fed groups. HDL-cholesterol concentrations of the FGP and BGP fed groups were significantly higher than control group, except of 1% BGP group. LDL and VLDL-cholesterol contents were significantly lower in 3% FGP group, and the same tendency atherogenic index and cardiac risk factor. GOT, GPT, and ${\gamma}$-GTP activity of serum were lower in FGP and BGP fed groups than control group. Glycogen contents in liver significantly higher than control group, and has not significantly difference between normal group. TBARS content was no significantly difference in the liver and serum, but in the kidney, 3% FPG and BGP fed groups were significantly lower than other experimental group. DPPH radical scavenging activity of liver has not significant difference among experimental groups, but activity was higher garlic extract powder fed groups in serum and kidney. These results indicate that dietary supplements of fresh and black garlic extract powder was contributed to lower of blood glucose, loss prevention of glycogen in liver and improve of lipid metabolism.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.317-322
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• 2022

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), a chronic contagious disease in small ruminants. The prevalence of CLA has been reported to be >50% in Korean black goats. CLA is difficult to control due to a lack of efficient vaccines and treatment methods. Effective disinfection of the farm environment may be an alternative strategy for reducing the spread of C. pseudotuberculosis. The objective of this study was to evaluate the efficacy of commercial disinfectants against CLA. The six commercial disinfectants, largely composed of sodium dichloroisocyanurate, sodium hypochlorite, potassium monopersulfate triple salt, quaternary ammonium, citric acid, and copper sulfate, were tested against five different genotypes of C. pseudotuberculosis isolated from goat farms in Korea. Efficacy tests were performed in accordance with the disinfectant efficacy test guidelines recommended by the Animal and Plant Quarantine Agency of Korea with slight modifications. All disinfectants except for copper sulfate exhibited >99.99% killing efficacy under hard water conditions following 30 min of incubation, which is the recommended standard treatment time according to guidelines. The minimum bactericidal treatment time was evaluated by employing treatments for durations of 1, 5, and 15 min. The most effective compounds under hard water conditions were sodium dichloroisocyanurate, potassium monopersulfate triple salt, and sodium hypochlorite, exhibiting >99.99% killing efficacy after 1 min of treatment. In the aqueous solution forms, citric acid and the quaternary ammonium compound were the most effective, but required at least 5 min to kill >99.99% of the bacteria. The current study characterizes the killing efficacy of six commercial disinfectant active compounds against C. pseudotuberculosis. Thus, this study provides essential information regarding the efficacy of the disinfectants used to control CLA in goat farms.

• Food Science and Preservation
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• v.22 no.2
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• pp.281-289
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• 2015

This study was conducted to examine the effects of a supplemented Chungkukjang diet on oxidative stress and antioxidant nutrients in Streptozotocin (STZ, 45 mg/kg of BW, IP injection)-induced diabetic rats. Diets that contained soybean Chungkukjang powder (SC), Yakkong Chungkukjang powder (YC), and Yakkong Chungkukjang powder with black food added (YCB) were administered to the STZ-induced diabetic rats for seven weeks. The increased lipid peroxide contents of their serum and liver were slightly controlled by providing them three types of Chungkukjang. The retinol level in the serum was 7.5 times higher in the STZ-induced diabetic group after the provision of YC. The total antioxidant capacity (TAC) level in the serum was higher in the STZ-induced diabetic group after the provision of YCB. Also, the retinol and tocopherol levels in the liver of the STZ-induced diabetic rats increased after they were provided YCB, and the decreased reduced glutathione (GSH) /oxidized glutathione (GSSG) level in their liver improved after they were fed a diet that contained YC. Moreover, the decreased anthocyanin level in the liver of the STZ-induced diabetic group improved after the provision of three types of Chungkukjang powder. These findings suggest that the Chungkukjang diet is a valuable food for the management of the health of diabetic patients and for the prevention of diabetic complications.

• Food Science and Preservation
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• v.20 no.4
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• pp.451-458
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• 2013

The purpose of this research is to distinguish the quantitative determination of phytochemicals in various agricultural products and to optimize an HPLC method for the determination of lycopene, lutein, ${\alpha}$-carotene, ${\beta}$-carotene, and cryptoxanthin. Among the different conditions studied, the most suitable ones for our samples were the extraction with hexane/acetone/ethanol (50:25:25, v/v/v), dissolution of the dry extract in tetrahydrofuran/acetonitrile/methanol (15:30:55, v/v/v), injection on a $C_{18}$ column with methanol/acetonitrile (90:10, v/v) + triethylamine $9{\mu}M$ as mobile phase, and ${\lambda}_{detection}$=475 nm. The mean percent recovery for the HPLC method were $120.7{\pm}4.1%$ (lycopene), $89.2{\pm}3.5%$ (lutein), $91.2{\pm}2.9%$ (${\alpha}$-carotene), $99.1{\pm}4.4%$ (${\beta}$-carotene), and $100.0{\pm}5.3%$ (cryptoxanthin). The contents of lutein in the agricultural products were spinach, kiwi, tomato, blueberry, melon, respectively. However, the lycopene contents were the highest in the Black tomato ($56.66{\pm}7.48mg/kg$) and Jangseong tomato ($50.28{\pm}5.42mg/kg$). The concentration of ${\beta}$-carotene in all of the agricultural products ranged from 0.07 mg/kg to 65.03 mg/kg. The quercetin content of the agricultural products increased in the order of blueberry (986.57~1,054.06 mg/100 g), kiwi (44.96~55.09 mg/100 g), hallabong (31.92~35.60 mg/100 g), and tomato (26.38~34.94 mg/100 g). The highest kaempferol content was found in the blueberry (47.79~76.15 mg/100 g) with results in all of the tested samples varying between 6.54~48.11 mg/100 g. The total polyphenol contents of the various agricultural products increased in the blueberry (213.60~229.96 mg/100 g), spinach (112.50~141.67 mg/100 g) and kiwi (46.49~70.44 mg/100 g). The total flavonoid content was the highest in both blueberry and spinach. Vitamin C content was detected in kiwi > hallabong > tomato > blueberry, respectively. The total anthocyanin contents (TAC) was detected in the Damyang blueberry and the imported blueberry.