• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1270-1276
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• 2013

Laver, a red algae belonging to the genus Porphyra tenera, is one of the most widely consumed edible seaweeds in Korea, China, and Japan. Lavers are usually consumed in dried, roasted, and seasoned forms to improve their palatability. We evaluated the composition of amino acids, minerals, and trace heavy metals in these three differently cooked forms of laver. The moisture and ash contents of three differently cooked lavers ranged from 1.49~9.69% and 6.07~10.31%, respectively. The crude protein and lipid content ranged from 17.24~36.88% and 0.52~42.42%, respectively. Dried laver was found to be a good source of amino acids such as taurine, alanine, and glutamic acid (871.10 mg, 833.53 mg, and 719.77 mg per 100 g dry weight, respectively). Laver was a good source of macro and micro minerals such as K, Ca, Mg, Na, P, I, and Fe, although laver more extensively cooked (roasted and seasoned) contained less minerals compared to the dried form. Mercury levels in the three differently cooked forms of laver were all less than 100 ng/g dry weight (the limit of detection with our methodology). The levels of arsenic were the most abundant elements in the differently cooked laver. There was a clear variation, depending on the cooking process, in terms of amino acid, mineral, and trace metal contents of laver.

• Investigative Magnetic Resonance Imaging
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• v.17 no.1
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• pp.19-25
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• 2013

Purpose : Renal blood oxygen level-dependent (BOLD) MRI has been used in the evaluation of renal oxygenation. We tried to provide the normal $R2^*$ value of the human kidney with 3.0 T, and evaluated the differences in $R2^*$ values according to gender and location. Materials and Methods: Twenty-four healthy volunteers underwent BOLD MRI at 3.0 T. Multi gradient echo-echo planar imaging sequence with seventeen echoes was used. After generation of the $T2^*$ map, the $R2^*$ was calculated. The statistical differences in $R2^*$ values between the cortex and medulla, males and females, and the right and left kidney were analyzed. The regional differences of $R2^*$ within the both kidneys were evaluated respectively. Results: BOLD MRI was successful in all participants. No gross artifact interfered with $R2^*$ measurement. The mean $R2^*$ at 3.0 T was $17.1{\pm}2.60s^{-1}$ in the cortex and $27.7{\pm}4.83s^{-1}$ in the medulla (p < 0.001). The $R2^*$ value in the medulla was significantly higher in the male than female volunteers (p = 0.025). There were no statistical differences of $R2^*$ according to the side and location in the kidney (p = 0.197). Conclusion: Renal BOLD MRI can be efficiently performed with 3.0 T MRI. Renal medullary hypoxia is present in normal volunteers. Our results may be used as reference values in the evaluation of pathologic conditions using BOLD MRI.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.358-366
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• 2013

The aim of this study was to evaluate the antimicrobial activities of Glycyrrhiza uralensis and Glycyrrhiza glabra extracts with various countries of origin. Three samples of licorice with various origins (Korea, China, and Uzbekistan) were evaluated for their antimicrobial activities against six skin microflora. The bioassay applied for determining the antimicrobial effects included the disc diffusion assay, minimum inhibitory concentration, and challenge test. The ethyl acetate fractions of G. uralensis and G. glabra extracts showed significant antimicrobial activities against two gram-positive (Bacillus subtilis, Propionibacterium acnes) and two gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. These samples had much more intensive antimicrobial activities than synthetic preservatives on B. subtilis, P. acnes, and P. aeruginosa, especially. Korean licorice showed the highest antimicrobial activity amongst the samples tested. In view of the observed inhibitory features of these G. uralensis and G. glabra extracts, it is suggested that they could be used as natural antiseptics against bacterial contamination in cosmetics and foods, instead of the common synthetic preservatives currently employed.

• Journal of Preventive Medicine and Public Health
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• v.42 no.2
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• pp.96-103
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• 2009

Objectives : We evaluated the health effects of exposure to BTEX(Benzene, Toluene, Ethylbenzene, m,p-Xylene, o-Xylene) in the Taean area after the Hebei Spirit oil spill. Methods : We used a questionnaire survey to look for health effects among 80 pregnant women 2 to 3 months following the Hebei Spirit oil spill. Their BTEX exposures were estimated using the CALPUFF method. We then used a multiple logistic regression analysis to evaluate the effects of BTEX exposure on the women s health effets. Results : Pregnant women who lived near the accident site reported more symptoms of eye irritation and headache than those who lived farther from the site. There was a trend of decreasing symptoms with an increase in distance from the spill site. Pregnant women exposed to higher ambient cumulative levels of Xylene were significantly more likely to report symptoms of the skin(OR 8.01 95% CI=1.74-36.76) in the first day after the accident and significantly more likely to report abdominal pain(OR 3.86 95% CI=1.02-14.59 for Ethylbenzene, OR 6.70 95% CI=1.82-24.62 for Xylene) during the 1st through 4th days following the accident. Conclusions : This study suggests that exposure to BTEX from an oil spill is correlated with an increased risk of health effects among pregnant women. This implies the need to take proper measures, including the development of a national policy for environmental health emergencies and a plan for studying the short- and long-term chronic health effects associated with such spills.

• Journal of Food Hygiene and Safety
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• v.24 no.1
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• pp.56-62
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• 2009

Patulin, a mycotoxin mainly produced by Penicillium and Aspergillus, is found in various foods. In the present, a maximum acceptable level for patulin is established at $50{\mu}g/kg(ppb)$ in apple juices and apple concentrates in Korea. But patulin may be detected in foods produced with other fruits. In the present study, patulin contamination was analyzed in 520 samples of fruit juices and beverages, and 50 samples of fruit juice concentrates. High performance liquid chromatography(HPLC) was applied to quantitatively analyze patulin levels in samples and liquid chromatography-mass spectrometry(LC/MS/MS) was used to remove false positive results. The results showed that three samples of 520 fruit juices and beverages and five samples of 50 fruit juice concentrates were contaminated by patulin, $9.8-18.0{\mu}g/kg$ and $4.7-18.2{\mu}g/kg$ respectively. Contaminated samples were produced with apple, orange or pear. This indicates that it is necessary to extend the regulatory range of patulin. In the other hands, the present study confirmed the effectiveness of LC/MS/MS analytical method to remove false positive results.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.121-127
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• 1985

In studying the structural work on ciguatoxin, parrot fish collected were identified as Scarus sordidus, S. frenatus, S. scaber and S. pectarlis, in which only S. sordidus contained toxic materials. Crude toxins obtained by silicic acid column chromatography, could be separated on a DEAE-cellulose column into two fractions, ST-1(less polar) and ST-2(polar) eluted with chloroform and chloroform-methanol(1:1). Furthermore ST-1 could be changed into ST-2 by repeated chromatography on DEAE-cellulose. Rf values of ST-1 and ST-2 were 0.60-0.75 and 0.30-0.54 on TLC coated with silica gel 60F-254 developed by chloroform-methanol-water-acetic acid (90:9.5:0.2:0.3) mixture. The peaks of ST-1 and ST-2 were not observed on each HPLC chromatogram at low sensitivity(2X), but by bioassay they were detected in the fraction of 24-27ml(less polar toxin, 120ng) and 22-27 ml (polar toxin, 150 ng). Less polar ciguatoxin from morey eel viscera also showed its peak in the same elution volume(25ml). Being subjected to chromatography on basic aluminum oxide (activity grade I) or to alkaline treatment, followed by basic aluminum oxide (activity grade I) chromatography ST-1 toxin was remarkably converted into the polar toxic component supposed to be polar ciguatoxin in both cases. In the latter case, approximately 74% of the residual toxicity was changed into the polar component, accompanied by about 50% loss of the initial toxicity. More than 26% of ST-2 toxicity was transformed into the less polar toxic component supposed to be less polar ciguatoxin on a deactivated aluminum oxide (activity grade V) column.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.322-327
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• 2006

Food constituents analysis of Acer tegmentosum. Maxim.(Acer TM) stem was carried out according to AOAC method, and the antiradical activity on DPPH and cytotoxicity on human cell lines (AGS, HepG2, A549, MCF-7 and Chang) for the 80% ethylalcohol(EtOH) extracts of Acer TM stem were studied. The antiradical activity on DPPH radical of the ethylacetate(EtOAc) fraction of the bark showed a higher activity than that of $\alpha$-tocopherol, ascorbic acid and BHT. The inhibition activity of the 80% EtOH extracts from Acer TM stem on human cancer cell lines by SRB assay indicated a dose-dependent growth inhibition on most human carcinoma cells. The growth inhibition rate of each human cancer cell line showed 91.3% to AGS, 75.0% to A549, 74.1% to HepG2, and 70.2% to MCF-7 cells, respectively, when the 80% EtOH extract(1 mg/ml) of Acer TM stem was added.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.468-476
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• 2020

We aimed to analyze the microbiological quality of the ready-to-eat (RTE) side dishes collected from traditional markets, supermarkets, and cafeterias in Gyeonggi-do in 2019. A total of 108 samples were analyzed for total aerobic bacterial counts, coliforms and foodborne pathogens depending on place of purchase and cooking methods. Results show that Bacillus cereus was detected in 14 (12.9%) out of 108 samples of side dishes, while no other foodborne pathogens were detected. The mean detected level (range) of total aerobic bacteria depending on place of purchase was 5.8 log CFU/g (3.0 to 8.2 log CFU/g) for traditional markets, 4.3 log CFU/g (2.4 to 7.8 log CFU/g) for supermarkets, and 3.80 log CFU/g (0.0 to 6.8 log CFU/g) for cafeterias, indicating that there was a significant (P<0.05) difference in total aerobic bacterial counts among places of purchase. Among the samples, the highest counts of total aerobic bacteria and coliforms were detected in saengchae (raw vegetables), followed by namul (seasoned herbs, vegetables), bokkeum (stir-fried foods), and jorim (foods cooked in soy sauce). The growth of total aerobic bacteria in seasoned soybean sprouts was inhibited when the sprouts were stored at 4℃ up to 24 h, whereas bacteria rapidly grew at 20 and 35℃ after 3 and 6 h, respectively. These results reveal that storage temperature might play a significant role for the microbiological quality of seasoned soybean sprouts when they are sold in markets. Thus, this study suggests that RTE side dishes should be stored at refrigerated temperature when being sold at markets as well as after purchasing to improve their microbiological quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.4
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• pp.215-228
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• 1991

In the East Sea of Korea the vertical structure functions of the temperature field were evaluated and the characteristic thermal zone was classified by the use of the empirical orthogonal function(EOF) method. The East Sea of Korea within the hydrographic lines of 10-107 of the Fisheries Research and Development Agency of Korea(FRDA) can be divided into three thermal regions by the characteristics of the vertical temperature variability. They are the North Korean Cold Current(NKCC) region near the coast which extends parallel to the north-south direction, the Warm-Core(WC) region which dominates almost all the hydrographic stations of the Line 104 of the FRDA and occupies a few stations of the Line-103 and -105 with its axis at the Line 104, and the East Korea Warm Current(EKWC) region which is bisected into the northern and the southern part by the WC region, respectively. Considering the two most important modes, $85.20-98.20\%$ of the total variance of temperature variation are explained in the NKCC region, $85.20-92.90\%$ in the EKWC region, and$85.50-91.70\%$ in the WC region. The first mode has its peak value at the surface with the annual cycle of variation. The spatial pattern of the first mode portrays a coherent vertical variation in the EKWC region and a clear anti-correlation both in the NKCC region and in the WC region where the zero-crossing depths are loom and 200m, respectively. The second mode of the NKCC region is particularly noticeable, haying its peak at loom with coherent vertical variation. To study the time dependency of the vertical structure functions, the extended EOF(EEOF) method was used. The persistence of the first mode is less than 4 months in the study area. The annual variation of the first mode in the NKCC region is different from those in the WC region and in the EKWC region.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.902-915
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• 2004

Science drama can be an useful tool for understanding the nature of science, Science-Technology-Society relationship by providing indirect experiences to young students. Specific science concept and knowledge can also be learned with high interests. In this study, to explore the usefulness of science drama in elementary science lessons, two scripts of science drama and lesson plans were developed and implemented. Six step model for science drama lessons was also suggested. One was 'Manhattan Project' which dealt with social, ethical responsibility in using science & technology (science argument drama), and the other was 'Mom, My blood type is O' which explained the heredity of blood type (science concept drama). Two teachers were asked to write their journals during preparation and implementation of science drama lessons, and the lessons were observed by the researcher and video taped for analysis. Some students were interviewed just after the lessons by the teacher and all students were asked to write their impressions, change of their thought, what is leant etc. Overall responses of students and teachers on the two science drama lessons were very positive, 'Mom, My blood type is O' got more positive responses, and girls were more positive than boys. Some students anticipated another science drama even suggest topics for it. 'Mom, My blood type is O' was successful in making students (grade 3) understand the knowledge related with heredity of blood type (71% of the students got perfect answer). In 'Manhattan Project' students (grade 5) perceived more diverse location of responsibility after the lesson, but the danger and harmfulness of atomic power was embossed. This implied the need of more careful planning for the relevant learning activities before and after the play of science drama.Two teachers perceived the science drama as a new, useful tool for some subject which is hard to deal with by other teaching method. They were also satisfied with students' high interest and engagement during the science drama lessons but the extra time and effort for the lessons were pointed out as a main difficulties.