• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.564-569
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• 2012

Selenium was initially considered toxic to humans, but it was then discovered that selenium is essential for normal life processes. Selenium plays important roles in antioxidants. It is expected that chitosan microcapsules containing nano-selenium will be able to be used as a key material in bio-medical and cosmetic applications. The high concentration of chitosan derivatives guarantees increased antioxidative activity. Both inorganic and organic forms of selenium can be nutritional sources. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. The objective of this experiment was to study the antioxidative activity of chitosan nano-selenium. Our experiments were divided into five groups, in the presence of various concentrations(0.1%, 0.3%, 0.5%, 0.7%, and 0.9%) of chitosan. We performed an assessment of the antioxidant properties and cytotoxicity of respective concentrations of chitosan nano-selenium. The antioxidant activity was examined by the free radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl(DPPH) assay. The cytotoxicity effect was measured by means of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. As a result, the electron donating abilities of 0.1%, 0.3%, 0.5%, 0.7%, and 0.9% of chitosan nano-selenium exhibited effective andioxidant scavenging activity at 12.5 ${\mu}g/m{\ell}$ against DPPH radicals. 0.3% chitosan nano-selenium did not show cytotoxicity on human keratinocytes. In general, the cytotoxicity of 0.1% and 0.9% chitosan nano-selenium showed the lowest effects. Though low cytotoxicity of 0.5% and 0.7% chitosan nano-selenium exhibited 29.67% and 38.4% against human keratinocytes on adding 100 ${\mu}g/m{\ell}$ and 50 ${\mu}g/m{\ell}$, respectively, cell vitality was recovered with 200 ${\mu}g/m{\ell}$. These findings support the notion that chitosan nano-selenium may be useful as a new active ingredient source for bioactive compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1865-1872
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• 2015

This study attempted to investigate consumer perceptions and attitudes towards reducing sugar intake by providing data to develop guidelines for the government and food-related industries to encourage Korean consumers to maintain appropriate levels of sugar intake. A survey was conducted on 238 adult consumers regarding their purchasing power for products with high sugar content in Seoul and Bundang, Gyeonggi area from September 1~30, 2013. Nutritional information on sugary products had a greater impact than media and others' recommendations on consumer awareness regarding need to reduce sugar intake. External factors such as health and weight control were stronger reasons for consuming reduced amounts of sugar or sugar-free products than internal factors such as sweetness. However, internal factors-such as taste-did not have a greater effect on consuming reduced amounts of sugar or sugar-free products than environmental factors-such as absence of purchase channels. Consumers indicated higher acceptance for 50% reduction in sweetness of existing commercial products. Regarding methods of lowering sugar intake, sugar replacement and reducing sugar consumption both generally and at home were preferred. In addition, consumers were likely to pay 10~14% more for sugar-reduced products than for existing products. Overall, consumers expressed positive attitudes towards reducing sugar intake in the future, although those in their twenties tended to be more passive than other age groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.164-170
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• 2006

The purpose of this study was to compare the nutrient intakes, blood pressure, and biochemical values and lipid profile in blood according to smoking status. Subjects were recruited from Korean adult men, which included non-smoker (n=47), smoker (n=58), and ex- smoker (n=44) . Anthropometrical measurement, blood pressure measurement, dietary intake assessment using 24-hour recall method, and blood collection and analysis were conducted. The average age, height, weight, and BMI of the subject were 54.7 years, 165.8 cm, 67.3 kg, and $24.5\;kg/m^2 $, respectively. There was no significant difference in general characteristics among three groups. The mean daily intakes of energy and protein were 1740.9 kcal and 69.6 g. The daily folate intake of the smoker was significantly lower than that of the non- smoker or ex-smoker. However, cholesterol intake of the smoker was significantly higher than two groups. The daily total food intake was 1250.0 g for non-smoker, 1180.1 g for smoker, and 1237.5 g for ex-smoker. The mushrooms intake in the smoker was significantly lower than that in the ex - smoker. However, eggs intake of the smoker was significantly higher than two groups. The RBC count and serum GOT/GPT of the subjects were $4598.2\times1000/mm^3$ and 27.3/27.3 U/L. The WBC count, hematocrit and hemoglobin of the smoker were significantly higher than those of the non-smoker and ex-smoker. Blood pressure and serum lipids of the subjects were 128.3/75.5 mmHg for SBP/DBP, 180.2 mg/dL for total cholesterol, 160.8 mg/dL for triglyceride, 41.5 mg/dL for HDL-cholesterol, 106.5 mg/dL for LDL-cholesterol, and 3.5 for atherogenic index. Especially serum triglyceride of smoker was significantly higher than that of non-smoker. The above results revealed that some nutrient intakes, such as folate and cholesterol, and hematological findings, and serum triglyceride of the smoker were different from non-smoker. However, these differences were recovered to non-smoking status by prohibition of smoking. Therefore, in order to stop smoking, the effect of smoking on nutritional and health status should be informed to smoker and more systematic study should be conducted.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.696-702
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• 2007

This study was performed to investigate the antihyperglycemic effect of green tea extracts (GTE) in diabetic rats. Experimental animals used were alloxan-induced diabetic Sprague-Dawley (SD) rats; as a model of type 1 diabetes mellitus and Otsuka Long Evans Tokushima fatty (OLETF) rats, and as a model of type 2 diabetes mellitus. Animals were randomly assigned either to continue the ad libitum diet or begin a green tea extracts (GTE) contained diet. GTE extracted from green tea was supplemented in the diet (2%). Body weight, food intake, and blood glucose concentration were recorded for 4 weeks. Animals were killed and glucose, triglyceride, and asparate aminotransferase (AST) were analysed in blood. Food intake was not affected by GTE in both alloxan.induced diabetic and OLETF rats but body weight was slightly decreased by GTE in OLETF rats. The blood glucose concentration was markedly decreased by GTE supplementation in both alloxan-induced diabetic and OLETF rats; however, triglyceride and AST levels in serum of GTE treated animals were not changed. This study shows that GTE beneficially modulate blood glucose concentration in diabetic animals. Dietary supplementation with GTE could potentially contribute to nutritional strategies for the treatment of diabetes mellitus.

• Korean Journal of Organic Agriculture
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• v.17 no.4
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• pp.519-527
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• 2009

The main nutritional problem of sorghum$\times$sudangrass hybrid silage is low quality and dry matter (DM) contents. This experiment was conducted to evaluate whether field pre-wilting treatment of sorghum$\times$sudangrass hybrid silage increases DM content and forage quality of the silage. The experiment was a randomized complete block design with three replications. The treatments were consisted of five different wilting days: 0 day (direct cut silage), 0.5 day, 1 day, 2 days and 3 days. Sorghum$\times$sudangrass hybrid silage with pre-wilting showed low 4.00 pH values, however direct cut silage (control) showed a 4.30 value because of its high moisture content. The DM content of sorghum$\times$sudangrass hybrid silage with pre-wilting was high above 25.1% after 1 days, however that of direct cut silage had 17.6%. And the effluent of wilted silage was decreased with prolonged wilting period, but that of direct cut silage produced effluent of 183 mL/kg. Crude protein and ether extract with wilted silage were decreased, however crude ash was increased with prolonged wilting period. Silage with pre-wilting had higher acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents than control silages, while its non-fiber carbohydrate (NFC) showed the opposite results. Lactic acid and total organic acid were increased with prolonged wilting period. For the palatability of dairy goat, silage with 2 days wilting was highest among silages. The experiment results indicate that wilted sorghum$\times$sudangrass hybrid silage could be recommended as effective method for reducing effluent, increasing pH and forage quality more than direct cut silage. Optimum pre-wilting day of sorghum$\times$sudangrass hybrid silage may be 1 days.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.706-713
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• 2013

With pot-grown 4-year-old 'Fuyu' persimmon trees, this study evaluated the effect of different nitrogen (N) rates during summer on fruit characteristics, changes of leaf nutrients after harvest, reserve accumulation, and early growth the following year. A total of 0, 36 g N in June, and 72 g N in June and July was fertigated to each tree using urea solution. All the fruits were harvested on Nov. 3. Although not significant, fruits were larger for the 36 g and 72 g N than the 0 g N. Fruits for the 0 g N, having lower N concentration, were softer and had a better coloration and higher soluble solids, indicating that they matured earlier. SPAD value on Nov. 3 was 19.2 for the 0 g N and 54.9 for the 72 g N, and then the values linearly decreased in all the treatments by Nov. 14, exhibiting rapid leaf senescence. Specific leaf weight, being the lowest for the 0 g N, also gradually decreased during this period. Increasing N level significantly increased cross-sectional area of the trunk. Leaf N concentration on Nov. 3 was 0.87% for the 0 g N, whereas it was 1.18 and 1.52% for the 36 g and 72 g N, respectively. The N fertigation tended to increase leaf concentrations of soluble sugars, starch, and amino acids. Contents of N, P, K, soluble sugars, starch, and amino acids per unit leaf area gradually decreased in all the treatments during the 11 days after harvest, and the extent of the decrease was the lowest for the 0 g N. On the other hand, those of Ca, Mg, and protein did not consistently change during this period. The N fertigation resulted in higher concentrations of N in dormant shoots on Nov. 14, and although not great, it also increased soluble sugars, starch, amino acids, and protein. Clear differences were found in number of flower buds per one-year-old branch and total shoot length per tree the following year. The 72 g N trees had 5.6-fold more flower buds and 1.9-fold more shoot length, compared with those of 0 g N trees. However, it was noted that tree growth the following year was not significantly different between the 36 g and 72 g N the previous year. It was concluded that N rate during summer should be adjusted with considering the changes of fruit maturation, mobilization of leaf nutrients, and reserve accumulation.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.810-819
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• 2012

This study investigated the chemical composition, meat quality and volatile flavor compounds in loin and top round of Hanwoo beef (n=126) depending on different age groups (G1, <5; G2, 6-8; G3, >9 years old). The intramuscular fat content (%) was higher for loin and top round of G1 (p<0.05) than that in the other groups. There was no difference in age groups for the top round; however, the loin of G1 had lower protein content (p>0.05). Total collagen content was lower in the top round of G3 (p<0.05). The loin and top round muscles of G1 had higher $a^*$ values and lower Warner Bratzler shear force values than that in the other age groups (p<0.05). The loin muscles of G1 were lower in percentage of cooking loss and higher in the water holding capacity than the loin in the other groups (p<0.05). The loin of G1 had lower total content of saturated fatty acids, whereas the top round of G1 had higher total content of monounsaturated fatty acids and lower total content of polyunsaturated fatty acids than that in the other age groups (p<0.05). Alanine was the highest free amino acid in the loin of Hanwoo beef, followed by glutamine, glycine, isoleucine and proline. The loin of G1 had higher contents of threonine, alanine, valine, methionine, phenylalanine, leucine and lysine than those in the other groups (p<0.05). The loin of G3 contained higher 3-methylbutanal, furfural, octanal, 1-(acetyloxy)-2-propanone, 1-octanol, 2,5-dimethylpyrazine and 2-ethyl-2,5-dimethylpyrazine in volatile flavor components than the loin in G1(p<0.05).

• Journal of fish pathology
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• v.18 no.1
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• pp.19-28
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• 2005

Scuticociliatosis has badly settled one of most damaging diseases during the seedling production process of olive flounder. Paralichthys olivaceus in Korea. We isolated a new type of Scuticociliate from flounder. The parasite metamorphoses to ciliate and cyst phases with each other by environmental changes and survive for a relatively long span. The ciliate was measured average 41.8 ${\mu}m$ in length and 21.0 ${\mu}m$ in width, and cyst was 17.0 ${\mu}m$ and 13.5 ${\mu}m$, respectively. Nutritional condition was determined as a major parameter of metamorphosing between ciliate and cyst stages. The ciliate transforms to a cyst stage because of food shortage, and the cyst returns to a ciliate stage with a favorite environmental condition and shows active growth and reproduction. The ciliate multiplied at the maximal density of $2.9 {\times} 10^5 {m\ell}^{-1}$cells in vitro cultivation at $15 ^{\circ}C$temperature using MS BHI medium and bacterial food sources. The ciliate could be proliferated at a 2.5 to $30 ^ \circ}C$ temperature range, pH 6 to 9, and 1 to 55 ppt salinity. Particularly, it survived over one week at $0 ^{\circ}C$temperature showing a high resistance against unfavorable environmental conditions. And the cyst survived for 320 days in the condition of $5 ^{\circ}C$with no feeding, but its survival period was markedly shortened in higher temperature conditions. The chemotherapeutants (formalin and hydrogen peroxide) were clarified as effective chemicals against the ciliate during in vitro trials, but the effect of therapeutants differed in proportion, depending upon the density and the bathing time of chemical compounds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.172-183
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• 2017

Germinated brown rice (GBR) has received considerable attention over the last decade as a means of enhancing the nutritional value and health-promoting functions of rice. The effect of germination on the physicochemical and textural properties of brown rice (BR) was investigated in different rice varieties (Samkwang, Misomi, Chindeul, and Hyeonpum). Cooking properties, such as water absorption, expanded volume, and soluble solids were significantly increased by germination in all rice varieties. Textural properties (hardness, toughness, adhesiveness, and stickiness) of cooked samples were determined using a texture analyzer. Hardness and toughness were decreased by germination, whereas stickiness and adhesiveness increased significantly. These results revealed that germination leads to improvements in the cooking and eating properties of BR. In Rapid Visco Analyzer (RVA), significant reductions were observed for peak viscosity, break down, set back, and final viscosity after germination. Although the amylose content of Misomi was slightly decreased by germination, that of other varieties increased significantly. Germination induced no noticeable change in the average chain length of amylopectin in Misomi, Chindeul and Hyeonpum, but led to a significant increase in Samkwang.

• Journal of dental hygiene science
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• v.17 no.6
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• pp.487-494
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• 2017

There is little evidence on the effects of environmental tobacco smoke (ETS) on prevalence of periodontal disease. The aims of this study were to explore the trends of prevalence of periodontal disease and types of exposure to smoke, including ETS according to the survey year, identify factors affecting periodontal disease, and compare the effect size of periodontal disease between active smokers and secondhand smokers. Data on 11,643 individuals were obtained from the fourth and fifth Korean National Health and Nutritional Examination Surveys. Information on exposure to ETS at home and work was self-reported. Severity of periodontal disease was evaluated using the community periodontal index. A multivariate logistic regression analysis was performed to model periodontal disease using types of smoking and the survey year. Overall, the prevalence of periodontal disease was 26.0% (n=3,029) and about 9% of the study population were secondhand smokers. The prevalence of periodontal disease among smokers was significantly increased according to smoking types by year. Active smokers showed a statistically significant adjusted odds ratio (aOR) for having periodontal disease except in the year 2007, whereas secondhand smokers had significant associations only in 2010 (aOR, 1.68; 95% confidence interval, 1.05 to 2.70) compared to non-smokers. For secondhand smokers, the statistical relationship of predicting periodontal disease was weaker than that of active smokers. However, ETS should separately be considered as an important risk factor for periodontal disease. This study suggested the need for further investigation of the impact of ETS on prevalence of periodontal disease using in-depth research designs and objective measurements for assessing periodontal disease and ETS.