• 농약과학회지
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• 제2권2호
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• pp.22-28
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• 1998

기질 화합물로써 26종의 2-thienyl 및 2-furyl 등 헤테로 고리($R_{l}$)가 치환된 방향족 ${\alpha},{\beta}$-불포화 케톤 유도체를 합성하고 벼도열병균(Pyricularia oryzae)과 토마토 역병균(Phytophtora infestans) 및 보리횐가루병균(Erysiphe graminis)에 대한 항균활성을 측정하여 치환($R_{2}$)-phenyl backbone의 변화에 따른 물리화학 상수들 사이의 정량적 구조-활성관계 (QSAR)를 검토하였다. 2-thienyl 치환체, 1-10의 벼도열병균에 대한 항균활성은 공명효과(R>0)와 분자굴절상수$M_{R}<0$)가 토마토 역병균의 경우에는 공명효과(R<0)와 입체효과(Es>0) 그리고 보리횐가루병균에 대하여는 치환기의 길이 ($L_{lopt.}=5.54{\AA}$)에 의존적이었다. 2-furyl 치환체, 11-26은 벼도열병균과 보리횐가루병균에 대하여는 공통적으로 적정값의 장효과 ($F_{opt}=0.49{\sim}l.11$)가 그리고 토마토 역병균에 대하여는 적정값의 입체효과($Es_{opt}=1.78$)와 지시변수들이 항균활성을 개선하는 요인으로 각각 영향을 미친다는 사실을 알았다. 그리고 2-thienyl 치환체들의 벼도열병균과 토마토 역병균에 대한 항균활성은 반비례 관계를 보이는 경향이었다.

• 농약과학회지
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• 제2권2호
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• pp.39-44
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• 1998

국내에서 많이 사용되고 있는 수도용 농약중 iprobenfos, isoprothiolane 및 diazinon의 수중 분해속도를 구명하기 위하여 수중 농약분해의 주요 요인인 가수분해, 미생물분해 및 광분해에 대해서 실험한 결과는 다음과 같다. Iprobenfos는 주로 미생물에 의해서 분해되었는데 반감기는 $4.0{\sim}5.7$일이었고, 고온일수록 가수분해가, pH가 낮을수록 분분해가 촉진되었다. Isoprothiolane은 미생물과 광에 의해서 주로 분해되었는데 광영향이 더 크게 작용한 것으로 나타났으며, 광분해는 pH 9.0에서 반감기가 91일인 반면 pH 4.0, 7.2에서는 각각 13, 16일로 pH가 낮을수록 분해가 신속하였다. Diazinon은 이 세가지 요인에 의해 분해가 일어났으며 pH가 낮을수록 가수분해가 매우 빠르게 일어났다. 농업환경에서 iprobenfos, isoprothiolane 및 diazinon의 수중분해는 각각 미생물분해, 광분해, 가수분해가 주요인으로 판단되었다. 시험농약을 분해하는 미생물을 동정한 결과 iprobenfos, isoprothiolane 및 diazinon은 각각 Pseudomonas putida, Alcaligenes xylosoxydans, Klebsiella planticola/ornithinllytica었고 유사도는 $54.8{\sim}86.2%$였다.

• 농약과학회지
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• 제4권2호
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• pp.32-36
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• 2000

N-(2-fluoro-4-chloro-5-alkyloxyphenyl)-3,4-dimethyl-2-arylthio-5-oxo-2,5-dihydro-pyrrole, 유도체들은 0.1 g/ha 이하의 농도에서 발아 후(Post-emergence), 벼와 논피 (Echinochloa crus-galli)와 올챙이고랭이 (Scriptus juncoides)에 대하여 선택성을 나타내었으며 pyrrole 고리상의 $SR_{2}$-기가 변화함에 따른 구조와 제초활성과의 관계 (SAR)를 청량적으로 검토하였다. 전체적으로 $R_{1}$=propargyl-치환체 (IA), $1{\sim}12$가 $R_{1}$=2-chloro-2-propenyl-치환체 (IB), $13{\sim}16$보다 높은 제초 활성을 나타내었으며 phenyl 고리상의 위치별 제초활성은 meta > para > ortho의 순으로 meta-치환체가 양호하였다. IA의 논피에 대한 제초활성은 $SR_{2}$-기가 Es상수의 적정값 $(Es)_{opt.}=3.25$을 가질 때 가장 큰 제초활성을 보인 반면에 올챙이 고랭이의 경우에는 MR상수에 의존적이었다.

• 농약과학회지
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• 제17권2호
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• pp.84-93
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• 2013

Isopyrazam은 신규 농약으로 현재 국내에는 공정분석법이 확립되어 있지 않아 농산물 중 잔류농약 분석을 위한 개별 분석법 개발이 필요하다. 본 연구는 현미, 대두, 고추, 감귤, 참외, 오이를 대표 농산물로 선정하여 isopyrazam에 대한 공정 개별 분석법을 확립하고자 수행되었다. Isopyrazam의 syn과 anti 이성질체를 분석하기 위해 여러 가지 추출, 분배 및 정제방법을 비교하면서 최적의 조건을 충족해 가며 분석법을 확립하였다. 대표 농산물 시료 중 함유된 isopyrazam은 acetonitrile로 추출한 후 n-hexane으로 액-액 분배하였으며, florisil을 이용하여 정제한 후 HPLC/UVD로 최종 분석하였다. 시료 중 현미와 대두는 n-hexane/acetonitrile을 이용한 유지제거 과정을 추가하였다. 본 분석법의 isopyrazam에 대한 정량한계는 1.0 ng (S/N > 10)이었고, 분석정량한계는 0.04 mg $kg^{-1}$이었다. 회수율은 isopyrazam syn과 anti-isomer에서 각각 81.0~105.4%, 80.8~105.6%이었으며, 반복 간 분석오차는 10% 미만이었다. 분석성분에 대한 확인을 위하여 LC/MS SIM을 이용하였다. 본 연구에서 확립된 isopyrazam의 분석법은 우수한 정량성 및 재현성, 분석과정의 편의성을 고려할 때 농산물 중 잔류농약에 대한 검사 및 안전성 평가를 위한 공정 분석법으로 활용될 수 있을 것으로 사료된다.

• 농약과학회지
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• 제21권1호
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• pp.75-83
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• 2017

대표 농작물 중 살균제 pencycuron의 잔류량을 정밀하게 분석할 수 있는 단성분 분석법을 개발하였다. 대표 농작물로 배추, 사과, 현미, 고추를 선정하였으며, 정밀분석을 위해 고성능 액체크로마토그래피를 사용하였다. 농작물 시료 중 pencycuron 잔류분을 acetone을 이용하여 진탕 추출하고 에틸아세테이트/헥산을 이용한 액-액 분배법과 silica 크로마토그래피법을 통해 정제하였다. 역상 액체크로마토그래피를 이용해 UV 240 nm 파장에서 pencycuron를 정량분석하였으며, 질량분석기를 통해 잔류분을 확인하였다. 본 분석법을 통한 pencycuron의 기기정량한계는 2 ng으로 분석정량한계는 0.02 mg/kg이었다. 표준용액을 3수준(분석정량한계${\times}1$, ${\times}10$, ${\times}100$), 3반복으로 무처리 시료에 첨가하고 본 분석법의 회수율을 산출한 결과 72~108%이었다. 따라서, 본 분석법은 농산물 중 pencycuron 잔류분석을 위한 공전시험법으로써 분석개발기준을 충족하였다.

• Nutrition Research and Practice
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• 제5권5호
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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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• 제44권2호
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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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• 제34권2호
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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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• 제31권1호
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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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• 제34권7호
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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.