• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.84-93
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• 2013

Validated analytical methods for isopyrazam are meager or lacking. In the present study, a single residual analytical method was developed for isopyrazam in selected commodities. Isopyrazam was analyzed in brown rice, soybean, green pepper, mandarin, cucumber, and Korean melon. We tried different solvents and methods through extraction, partition and purification steps to obtain best analytical results. For isopyrazam samples were extracted with acetonitrile, concentrated and partitioned with n-hexane, clean-up using florisil with n-hexane/ethylacetate (70/30) and analyzed with HPLC/UVD. The limit of quantitation (LOQ) for isopyrazam was 1.0 ng (S/N > 10) and method LOQ (MLOQ) was 0.04 mg $kg^{-1}$. Recovery ranged through 81.0~105.3% (syn-isomer) and 80.8~105.6% (anti-isomer) at fortification level of 0.04 (MLOQ), 0.4 (10 ${\times}$ MLOQ), and 2.0 (50 ${\times}$ MLOQ). The coefficient of variation (CV) for isopyrazam was less than 10% regardless of sample types. These results were further confirmed with LC/MS, respectively. The proposed method is highly reproducible and sensitive and is suitable for routine analysis.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.75-83
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• 2017

The single residue analytical method was developed for determining fungicide pencycuron residues in various agricultural commodities with high-performance liquid chromatography (HPLC). Pencycuron residue was extracted with acetone from representative crops such as Korean cabbage, apple, brown rice and green pepper. After ethyl acetate/n-hexane partition and subsequent clean-up with silica gel chromatography, pencycuron residue was quantified by reversed phase HPLC with UV detection at 240 nm. The suspected residue of pencycuron was confirmed using selected-ion monitoring (SIM) LC/mass spectrometry (MS). Instrumental limit of quantitation (ILOQ) and method LOQ (MLOQ) were set at 2 ng and 0.02 mg/kg, respectively. Overall recoveries of pencycuron from different crop samples fortified at three levels (MLOQ, 10MLOQ, 100MLOQ) were 72~108%. This proposed method could be useful as official analytical method for quantification of pencycuron residues in agricultural commodities.

• Nutrition Research and Practice
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• v.5 no.5
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• pp.455-463
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• 2011

The aim of the present study was to assess the effects of skipping breakfast on diet quality and metabolic disease risk factors in healthy Korean adults. Subjects included 415 employees (118 men, 297 women; 30-50 years old) of Jaesang Hospital in Korea and their acquaintances. Data collected from each subject included anthropometric measurements, 3-day dietary intake, blood pressure, and blood analyses. The subjects were classified into three groups based on the number of days they skipped breakfast: 'Regular breakfast eater', 'Often breakfast eater', or 'Rare breakfast eater'. Participants in the 'Rare breakfast eater' group consumed less rice, potatoes, kimchi, vegetables, fish and shellfish, milk and dairy products, and sweets than did participants in the other two groups (P for trend <0.05) and ate more cookies, cakes, and meat for dinner (P for trend <0.05). Participants in the 'Rare breakfast eater' group consumed less daily energy, fat, dietary fiber, calcium, and potassium than did participants in the other groups (P for trend <0.05). The percent energy from carbohydrates was lower and fat intake was higher in the 'Rare breakfast eater' group than in the other groups (P for trend <0.01). When diets were compared using the Acceptable Macronutrient Distribution Range for Koreans, 59.1% of subjects in the 'Rare breakfast eater' group consumed more energy from fat compared with the other two groups (P <0.005). According to the Estimated Average Requirements for Koreans, intake of selected nutrients was lower in the 'Rare breakfast eater' group than in the other two groups (P <0.05). The risk of elevated serum triglycerides was decreased in the 'Rare breakfast eater' group (OR, 0.3 [0.1-1.0], P for trend=0.0232). We conclude that eating breakfast regularly enhances diet quality, but may increase the risk of elevated serum triglycerides.

• Journal of Nutrition and Health
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• v.44 no.2
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• pp.152-161
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• 2011

Koreans have undergone many changes in dietary patterns with economic growth. The purpose of this research was to examine changes in dietary patterns using data from the 1998, 2001, and 2005 Korean National Health and Nutrition Examination Survey. The study included 21,525 subjects (8,295 from 1998, 6,880 from 2001, and 6,350 from 2005) who were 20 years or older and who participated in a 24-h diet recall. The percentage energy intake from 22 food groups was calculated, and a cluster analysis was applied to identify dietary patterns. Two dietary patterns emerged; the first pattern was characterized by high intake of white rice, legumes, vegetables, kimchi, and seaweeds, the so-called "traditional" pattern (53%), whereas the other pattern was characterized by high intake of other grains, noodle dumplings, floured bread, pizza, hamburgers, cereals and snacks, potatoes, sugared sweets, nuts, fruits, meat·its products, eggs, fish, milk and dairy products, oils, beverages and seasoning, or the so-called "modified" pattern. The modified pattern comprised a higher proportion of younger aged, metropolitan residents with more education and higher incomes. However, the gender distribution was not significantly different. The modified pattern had a significantly higher intake of all nutrients except carbohydrates and had a higher proportion of energy from fat and protein. No association with a risk for metabolic syndrome was found for either dietary pattern. After age was standardized, the traditional pattern included 52% of the respondents in 1998, 54% in 2001, and 50% in 2005. However, the modified pattern was significantly more prevalent in the younger age group (20-29 yr), whereas the traditional pattern increased significantly in the older age group (${\geq}$ 65 yr). In conclusion, a secular trend was found for dietary pattern by age group, suggesting that it is necessary to monitor the changes in dietary pattern by age group and to develop appropriate dietary education and guidelines.

• Journal of Nutrition and Health
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• v.34 no.2
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• pp.123-131
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• 2001

The purpose of this study was to investigate the effects of diet composition on serum leptin and lipids profiles in rats. At the baseline, seven 4-week-old Sprague-Dawley rats, male, were sacrificed and the remaining rats were divided into five groups and each group was fed one of the following five dietary regiments for 2 weeks and 6 weeks;the control diet AIN76(CAL, n=2l), high-carbonhydrate(rice)(HCR, n=2l), high-carbohydrate(flour)(HCF, n=2l), high-fat(corn oil)(HFO, n=2l), high-fat(beef tallow)(HFB, n=2l). Serum leptin was determined by a double antibody ELISA assay at the baseline(n=7), 6 week(n=35) and 10 week of age(n=70). At 6 weeks of age, the increase in the Food Efficiency Ratio(FER) was related to adipocyte hyperplasia in rats on HFB diets. The serum triglyceride, total cholesterol, and LDL-cholesterol increased significantly in HFB group, and decreased in HFO group compared to control group. The HFC group showed significant increase in serum triglyceride level compared with control group. After 2 weeks and 6 weeks, noticeably high increases in epididymal adipose tissue fat cell mass and numbers were observed with the HFB fed group. Serum leptin levels increased as body weight increased over the period of time(4weeks; 1.50$\pm$0.13ng/ml versus 10weeks; 2.08$\pm$-.13ng/ml). And this result shows that there are 193% higher in rats fed high fat-beef tallow diet than the control diet. Serum leptin levels of the HFB group(4.01$\pm$0.39mg/ml) were significantly higher than that of the HFO(2.06$\pm$0.5613ng/ml), CAL(2.08$\pm$0.1313ng/ml), HCR(2.41$\pm$0.2113ng/ml) and HCF(2.80$\pm$0.4713ng/ml) at p<0.05. The serum leptin concentration was positively correlated with the amount of epididymal fat pads(r=0.47 p<0.01), serum triglyceride(r=0.49, p<0.001), tatal cholesterol(r=0.48, p<0.001), LDL-cholesterol(r=0.58, p<0.001), atherogenic index(r=0.67, p<0.001), and inversely correlated with HDL-cholesterol(r=-0.65, p<0.001). In conclusion, the changes in composition of dietary fat and carbohydrate intake could affect changes in concentration of serum lipids and leptin. Especially, the high-fat diet with animal fat source could increase circulating leptin level. (Korean J Nutrition 34(2) : 123-131, 2001)

• Journal of Nutrition and Health
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• v.31 no.1
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• pp.96-101
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• 1998

The prevalence of iron deficiency in later infancy and the toddler years(25% to 40% at 1 year of age) has not decreased remarkably , except in Western countries. The purpose of this study was to 1) determine the relationship between current feeding practices and iron status, and 2) assess compliance to infant feeding instructions. Two groupsof infants were examined. The first group of 302 infants aged 6 to 24months was seen at a well baby clinic while the second group of 135 infants of the same age group was assessed by venipuncture. Cutoff values for laboratory tests were as follows ; hemoglobin<11g/dL, mean corpuscular volume (MCV) <72fl ; red cell distribution width(RDW)>15% ; serum ferritin level<10ng/ml ; and transferrin saturation (serum iron(TIBC)<10%. The diagnosis of iron deficiency anemia (IDA) was made when a low hemoglobin level was associated with either low ferritin orlow transferrin saturation . Of the 302 children brought to the well baby clinic , 12.3%(n=37) were found to have anemia (hemoglobin<11.0/dL). In terms of children grouped according to feeding practices, it was found that children with anemial comprised 32.0% (24/75) of the prolonged breast-fed group (Group A), significantly more than the 4.0%(7/176) of the artificial milk feeding group(Group B). and 3.9%(2/51) of the switched from breast milk to iron -fortified weaning foods group(Group C).Among the 107 children with IDA , iron deficiency in 105 children(98.1%) was suggested by their dietary histories ; exclusive or prolonged breast-feeding for more than 6 months without iron fortification in 98 infants ; cow's milk consumption> 500ml/day without iron fortification during infancy(n=12), or >800ml without iron-fortified foods after infancy(n=15) ; and the use of unfortified forumula or unbalanced diets, mainly limited to rice gruel. Despite the relatively high (79.6%) motivation on the part of the infants mothers and supervison by professional personnel, the poor results in the infants receiving iron fortified foods were due to poor compliance(85.75). Among the mothers of 98 IDA patients who were contacted by telephone , it was revealed that 29% did not give the oral iron preparation for more than 2 months. Furthermore, negligence or disregard by the parents occurred in 14% of the case , discontinuance of the oral iron preparation by the parents due to side effects occurred in 6%, and the children's refusal or poor oral intake and no further trial occurred in 6%. The dietary history of a large group of infants was highly predictive of their risk for anemia . Continued consumption of breast milk until the age of 1 year is not warranted unless iron-fortified foods are given concomitantly. Because there is a problem with compliance, more successful and safe strategies for preventing iron deficiency woold included dual coverage in the from of therapeutic iron supplementation as well use of iron-fortified foods for teddlers who are at risk of iron deficiency.

• Journal of Nutrition and Health
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• v.34 no.7
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• pp.797-808
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• 2001

To determine folate intake and food sources in Korea college students, dietary survey was conducted in March, 1999. Dietary data were collected by trained interviewers using the method of 24-hour recalls for 3 consecutive days. The data of 44 male and 62 female students were analyzed with two different nutrient databases in Recommended Dietary Allowances for Korean on the 6th and 7th revisions, and the results were compared. The intakes of energy and nutrients except vitamin A and folate were lower when analyzed with the 7th database than the 6th database. Mean daily folate intakes with the 6th and 7th databases were 172.9$\mu\textrm{g}$, 221.6$\mu\textrm{g}$ for male students while 125.1$\mu\textrm{g}$, 168.0$\mu\textrm{g}$ for female students, respectively. The results showed significantly higher estimates of folate intake with the 7th database, and significantly higher intake in males than females analyzed with both the 6th and 7th databases. Daily folate intake per 1,000kcal (folate density) was 71.1$\mu\textrm{g}$/1000kcal for males and 67.6$\mu\textrm{g}$/1000kcal for females with the 6th database, and 97.9$\mu\textrm{g}$/1000kcal for males and 95.5$\mu\textrm{g}$/1000kcal for females with the 7th database. The differences in folate density between the two databases were signficant, but the differences between the gender were not significant. The proportions of the subjects who consumed more than the RDA of 250$\mu\textrm{g}$ with the 6th and 7th databases were only 4.6%, 29.6% of males and 1.6%, 9.7% of females, respectively. The biggest food source of folate was Kimchi, contributing 17.9% for male and 13.7% for female students with 7th database. Laver, spinach, Ramyon, rice, and Ko Chu Jang together with Kimchi contributed 41.9% for male and 32.4% for females students with the 7th database. These results imply that folate intake reported in the reported inthe previous studies using the 6th database was underestimated. However, the 7th database seems to be still incomplete since 20.5% of 2,932 foods in the database were derived from the other sources, and the rest were imputed from similar foods. Therefore, in order to accurately estimate folate intake of Koreans, folate contents in major contributing foods need to be measured using an appropriate assay method.

• Journal of Nutrition and Health
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• v.6 no.2
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• pp.25-33
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• 1973

With the object of the study id every possible correlation between daily food intake and growth rate of primary school students, aged eleven years old, the author distributed prepared questionnaires through 200 children of 5th grade in both sexes in K private primary school, Seoul. Specific object of this study were included following three points: such as daily food intake records for six days. daily food intake records for six days. school records of sample children at the end of 4th grade. physical growth index calculated by means of weight and height of sample children at the first part of the 5th grade. CR. t. F. test as well as percentage calculations were included for statistical analysis. The result of this study were as follows: 1. For the living circumstances a) Average numbers of brother and sister in sampled family were two to three. b) Approximately 50%of the children were brought up by mother's milk at their infants and about 35% of children were weaned at the age of 7 to 12 months. c) Thirty to forty percent of the respondents revealed irregulity in their meal time due to early school time in the morning. d) Monthly average expenditure for daily food reached 20 to 29% out of total income. e) The most favorit foods reflect as follows: The most favorit main dish is boiled rice mixed with other careals and side dish beaf. Fruits and juice are more popular snack among whole children. 2. Nutrition survey a) The calcium and thiamine were the most limited factors out of daily nutrients consumption. b) The total calory intake were composed of carbohydrate 63%, protein 16% and fat 21% respectively. c) The total food intake were composed of 20 to 24% of animal source of foods and 76 to 80% of plant source of foods (vegetables, grains, fruits) d) The total protein intake were composed of 46% of animal protein and 54% of others. e) The grain stuffs consumed in the largest quantity at the level of 50% out whole food groups. f) Twenty four percent of total food intake came from snack between meal time. 3. The result of statistical analysis were as follows: a) The correlation between the calory intake and plysical growth index revealed statistical significancy at the level of p<0.001. b) The correlation between the protein intake and physical growth index revealed statistical significancy at the level of p<0.001. c) The correlation between the meal time and physical growth index revealed statistical significancy at the level of 0.02

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.106-115
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• 2014

Traditional village forests called Dangsan forests represent unique cultural landscape as a national cultural asset in Korea with a history of more than several hundred years. Cultural heritage can retain their value when they are fully sustained their authenticity and management scheme. The Dangsan forests established in a large area have been designated as a natural monument by Cultural Heritage Administration. Small scale Dangsan forests, however, are not introduced to the public and on the verge of disappearance. Dangsan forests have a value as a core landscape element in rural landscapes of Korea. The two villages at Ijeon-ri, Cheongsong-gun have small Dangsan forests where Dangsan ritual is performed. At one of the villages, there is Jusanji Reservoir designated for Scenic Site # 105, from which the water is used for growing crops. In this study, the landscape characteristics of the Dangsan forests were investigated including rice paddy field, stream, and the Jusanji Reservoir. A conservation measure of rural landscape for sustainable management scheme was suggested by designating 'Conservation area of agricultural landscape ecology'. Dangsan forests, especially where they are in small scale like those of Ijeon-ri, tend to be neglected. The Dangsan forests ought to be recognized for their value and by providing a management scheme including neighborhood elements such as farm fields and streams they can be revitalized to be core areas for conservation of rural landscape.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1413-1420
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• 2014

Phytate is an antinutritional factor that impacts the bioavailability of essential minerals such as $Ca^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Zn^{2+}$, and $Fe^{2+}$ by forming insoluble mineral-phytate salts. These insoluble mineral-phytate salts are hydrolyzed rarely by monogastric animals, because they lack the hydrolyzing phytases and thus excrete the majority of them. The ${\beta}$-propeller phytases (BPPs) hydrolyze these insoluble mineral-phytate salts efficiently. In this study, we cloned a novel BPP gene from a marine Pseudomonas sp. This Pseudomonas BPP gene (PsBPP) had low sequence identity with other known phytases and contained an extra internal repeat domain (residues 24-279) and a typical BPP domain (residues 280-634) at the C-terminus. Structure-based sequence alignment suggested that the N-terminal repeat domain did not possess the active-site residues, whereas the C-terminal BPP domain contained multiple calcium-binding sites, which provide a favorable electrostatic environment for substrate binding and catalytic activity. Thus, we overexpressed the BPP domain from Pseudomonas sp. to potentially hydrolyze insoluble mineral-phytate salts. Purified recombinant PsBPP required $Ca^{2+}$ or $Fe^{2+}$ for phytase activity, indicating that PsBPP hydrolyzes insoluble $Fe^{2+}$-phytate or $Ca^{2+}$-phytate salts. The optimal temperature and pH for the hydrolysis of $Ca^{2+}$-phytate by PsBPP were $50^{\circ}C$ and 6.0, respectively. Biochemical and kinetic studies clearly showed that PsBPP efficiently hydrolyzed $Ca^{2+}$-phytate salts and yielded myo-inositol 2,4,6-trisphosphate and three phosphate groups as final products. Finally, we showed that PsBPP was highly effective for hydrolyzing rice bran with high phytate content. Taken together, our results suggest that PsBPP has great potential in the animal feed industry for reducing phytates.