• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.220-227
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• 2021

Fluoroimide is a fungicide and is also used as a pesticide for persimmons and potatoes. The established fluoroimide pesticide analysis method takes a long time to perform and uses benzene, a carcinogen. In addition, a lower limit of quantification is required due to enforcement of the Positive List System. Therefore, this study aimed to improve the analysis method for residual fluoroimide to resolve the problems associated with the current method. The analytical method was improved with reference to the increased stability of fluoroimide under acidic conditions. Fluoroimide was extracted under acidic conditions by hydrogen chloride (4 N) and acetic acid. MgSO₄ and NaCl were used with acetonitrile. C₁₈ (octadecylsilane) 500 mg and graphitized carbon black 40 mg were used in the purification process. The experiment was conducted with agricultural products (hulled rice, potato, soybean, mandarin, green pepper), and liquid chromatograph-tandem mass spectrometry was used for the instrumental analysis. Recovery of fluoroimide was 85.7-106.9% with relative standard deviations (RSDs) of less than 15.6%. This study reports an improved method for the analysis of fluoroimide that might contribute to safety by substituting the use of benzene, a harmful solvent. Furthermore, the use of QuEChERS increased the efficiency of the improved method. Finally, this research confirmed the precise limit of quantification and these results could be used to improve the analysis of other residual pesticides in agricultural products.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.377-385
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• 2022

This study examined the dietary fiber content of potato and physicochemical characteristics of potato starch isolated from various cultivars. The total dietary fiber content of the Arirang1ho cultivar was 6.30%, which was higher than that of other cultivars. The amylose content ranged from 36.76-55.75%, with Sooseon having the highest amylose content. Analysis of the degree of amylopectin polymerization revealed that all cultivars had a high proportion of DP (degree of polymerization) 13-24. The phosphate content ranged from 45.90-84.23 mg/100 g, with Arirang1ho having the highest and Eunseon having the lowest phosphate content. The resistant starch content ranged from 58.94-79.87%. Geumseon showed the highest breakdown in the range of 587.45-1,129.72 RVU (rapid viscosity unit). Sooseon had the lowest gelatinization enthalpy value for potato starch in the range of 5.54-7.64 J/g. These results provide basic data for the use of potatoes in industrial applications.

• Journal of Bio-Environment Control
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• v.32 no.2
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• pp.172-180
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• 2023

This study was carried out to determine the sprouting period of early and mid-season varieties, which includes 'Atlantic', 'Chubaek', and 'Superior', during the summer storage period in a semi-underground warehouse without cooling system. And also it was investigated the effect of chlorpropham [Propan-2-yl N-(3-chlorophenyl)carbamate, CIPC] treatment on the sprouting inhibition for the varieties. This study was conducted to figure out a sprout inhibitory effect when CIPC was applied to 1kg of the potato tubers at concentrations of 10 mg and 20 mg which are lower than the treatment concentrations of ca 30 mg prescribed by the positive list system (PLS). The internal temperature of the warehouse used in this experiment was lowered by 5℃ or more than the outside temperature. The difference between the lowest and highest temperature during the experiment throughout the day was 5℃. It showed the effect of reducing to 1/2 of the difference in outdoor temperature. As for the sprouting of potatoes, the extremely early variety 'Chubaek' sprouts appeared at the 6th week of storage of control and it was the fastest sprouting potato among the control groups of the varieties. Sprouting began to appear in the Superior at the 6th week of storage, while the 'Atlantic' sprouted at the 8th week of storage. The appearance of sprouts was suppressed in all treatment groups of 'Atlantic' and 'Superior' varieties in CIPC treatments. Sprouts were observed in all treatment groups of 'Chubaek' after the 7th week, but the elongations of the sprouts in tubers were completely inhibited until the 8th week of storage. 'Atlantic' and 'Superior' seemed to have a sprouting inhibitory effect even with a low CIPC concentration of 10 mg·kg^-1, with the exception of extremely early variety 'Chubaek' that breaks out of the dormancy quickly. Although weight loss occurred continuously during storage, it was minor loss of 0.7-1.6%. There was no consistent trend for changes of the loss in the varieties and CIPC treatments. Most common pathological disorder was the dry rot during the experiment, but only few were affected. The use of the tubers treated at 18℃ and 90% RH for 10 days and the rack of refrigeration system which lead to lack of convection seemed to have suppressed the spread of pathogens.

• The Korean Journal of Zoology
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• v.14 no.2
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• pp.57-74
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• 1971

The present investigation has been done to observe the ecological habits of field mice to protect the rice from damages during the growing season in paddy-field and during the storge period. The results obtained are summarized as follows: 1. Of 155 mice captured in the period of April-November 1970, which belong to four genera (Apodemus, Cricetulus, Rattus, and Micromys), 148 mice(95%) were found as striped field mice (Apodemus agrarius coreae). The population density of striped field mouse was revealed by the present study as 55/ha, which is quite a low level compared with that in Japan of 900/ha. 2. The age distribution of the mice as judged by their body weight was found mainly composed of adult and the sex ratio was found to be 1.8 as determined with 147 individuals. The nest was found to be occupied by an adult and was composed of at least three openings and more than one food storage tunnels. The mice usually keep hulled rice rather than unhulled one in storage tunnel. The weight of food found in a nest was about 50 grams on an average. 3. The mice show a most active behaviour 1-2 hours after the sunset, around midnight, and an hour before the sunrise, but they are active even in daytime in order for searching for food and for breeding. 4. The ratio (%) of damage appeared in high stem of sweet corn in August was 30 ~ 40 percent, whereas that in low stem was 80 ~ 90 percent. The weight of spoiled grains in paddy-field was 11, 400gm/0.4ha and this gives an estimate of 349, 695 for whole country. 5. The female striped field mouse weighs average of about 30 grams and gives birth to average of 4.8 younglings which wean away from female mouse three weeks after delivery. 6. The natural enemies to the mice are found to be carnivores (weasel, cat, mountain cat, fox, raccoon, and otter), raptatores(eagle, owl, kete, buzzard), and snakes. Two kinds of field rats(Rattus norvegicus, Cricetulus tritor) are also the predator to the mice. 7. The feeding preference of striped field mice follows in decreasing order of sweet corn, soybean, sweet potatoes, chestnut, and wheat. The mice do not have a preference for barley, millet, rough millet, red bean, and green bean. 8. The starvation experiment, in which water alone was supplied, revealed that the mice in good physical and nutritional conditions survived for 71 ~ 79 hours, whereas those in worse conditions survived for only 32 ~ 39 hours.

• Journal of Nutrition and Health
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• v.56 no.5
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• pp.496-509
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• 2023

Purpose: This study aimed to identify the general characteristics, chronic diseases, health behavior, mental health, and nutritional status of young-old women based on their vitality. Methods: This study used data from the 2019 and 2021 Korea National Health and Nutrition Examination Survey (KNHANES). The subjects were 1,113 young-old women aged 65 to 74 years old. The health-related quality of life concept with an 8-item questionnaire was used to measure the quality of life. Subjects were categorized into 4 groups (always, often, sometimes, never) based on their vitality. General characteristics, chronic diseases, health behavior, dietary behavior, food intake, and nutrient intake were compared among the groups. Results: Age, education level, household income, employment, fruit intake, dietary supplements, abundance of food, and nutrition labeling recognition were associated with the vitality of the subjects. Young-old women with arthritis, diabetes, and osteoporosis displayed lower vitality. Moreover, subjective health status, exercise, activity restrictions, and average daily sitting hours were related to vitality, while no significant difference was found in vitality between smoking and drinking. In terms of mental health factors, higher vitality was associated with 6-8 hours of sleep, lower stress levels, and reduced depression. The high-vitality group exhibited a higher intake of potatoes, starch, mushrooms, fruits, meat, milk, animal oils, and beverages than the low-vitality group. Additionally, the group with higher levels of vitality showed a higher intake of protein, fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, n-6 fatty acids, dietary fiber, sugars, phosphorous, potassium, magnesium, iron, zinc, and riboflavin. Conclusion: This study suggests that the vitality of young-old women is related to socioeconomic factors, health behavior, mental health, and food intake. To maintain a vibrant lifestyle in elderly women, it is necessary to have social and economic stability, prevent arthritis, diabetes, and osteoporosis, exercise regularly, get sufficient sleep, maintain mental health, and have a balanced diet.

• Journal of Plant Biotechnology
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• v.50
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• pp.1-10
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• 2023

Sweet potato (Ipomoea batatas L. Lam) is an economically important root crop and a valuable source of nutrients, processed foods, animal feeds, and pigment materials. However, during post-harvest storage, storage roots of sweet potatoes are susceptible to decay caused by various microorganisms and diseases. Post-harvest curing is the most effective means of healing wounds and preventing spoilage by microorganisms during storage. In this study, we aimed to identify proteins involved in the molecular mechanisms related to curing and study proteomic changes during the post-curing storage period. For this purpose, changes in protein spots were analyzed through 2D-electrophoresis after treatment at 33℃ (curing) and 15℃ (control) for three days, followed by a storage period of eight weeks. As a result, we observed 31 differentially expressed protein spots between curing and control groups, among which 15 were identified. Among the identified proteins, the expression level of 'alpha-amylase (spot 1)' increased only after the curing treatment, whereas the expression levels of 'probable aldo-keto reductase 2-like (spot 3)' and 'hypothetical protein CHGG_01724 (spot 4)' increased in both the curing and control groups. However, the expression level of 'sporamin A (spot 10)' decreased in both the curing and control treatments. In the control treatment, the expression level of 'enolase (spot 14)' increased, but the expression levels of 'chain A of actinidin-E-64 complex+ (spot 19)', 'ascorbate peroxidase (spot 22)', and several 'sporamin proteins (spot 20, 21, 23, 24, 27, 29, 30, and 31)' decreased. These results are expected to help identify proteins related to the curing process in sweet potato storage roots, understand the mechanisms related to disease resistance during post-harvest storage, and derive candidate genes to develop new varieties with improved low-temperature storage capabilities in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.826-836
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• 2010

This study was conducted to compare the dietary habits, nutrient intake and health status of female college students at Sahmyook University according to their majors. Specifically, women majoring in literature and science (77), food and nutrition (103) and sport (73) were evaluated. College women in the sports department were more likely to have a part-time job and had greater expenses than women in the other departments. The average height of college women in the sports department (164.3${\pm}$4.6 cm) was 2.04 cm taller than that of women with other majors (162.3${\pm}$4.7 cm). College women in the department of literature and science were more likely to have an unbalanced diet, even though they commonly ate small amounts of fruit as snacks. They were more prone to take nutrient tablets and vitamins when compared to women in the other departments. College women in the department of sport were more likely to have unbalanced meals (31.5%) and to overeat. Students in the department of food and nutrition ate more fruit, vitamin C and E but less cholesterol containing foods (p<0.05), less fast food and fried food than students in the other departments. The subjects in the department of sport ate less bread, sweet potatoes, fast foods and fried foods but more calories, fat, vitamin A, vitamin B, niacin, Ca, P and cholesterol than students in the other departments (p<0.05). They were also more likely to exercise for more than two hours a day. The most common problems among college women were going without meals, eating an unbalanced diet, overeating, intake of ill-balanced nutrients and lack of exercise. It was found that college women in the department of sport had a better intake of nutrients and maintained healthier life styles.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.856-868
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• 2009

This study was conducted to investigate causes for health problems among college women by analyzing factors related to their dietary habits, physical development, health habits, and blood parameters. The subjects were ages 20 to 24 years, lived in the Seoul area and were randomly selected during March, 2008 to August, 2009. The average height and weight of the overall subjects were $162.02{\pm}4.89\;cm$ and $53.96{\pm}7.00\;kg$, respectively. According to a 3-point assessment scale for the subjects' dietary habits, the average point value was 21.2. The percentage of subjects that ate breakfast daily was only 30.5%, and they omitted regular meals at least once a week. Approximately 83.5% of the subjects reported eating out often or frequently, and preferred Korean foods when they ate out. The subjects had interim meals (snacks) one or two times daily, and 40.4% of them preferred unbalanced meals. As their interim meals, among the 'good' group, ate breaded potatoes (39.3%), carbonated beverages, and ice cream (36.8%), whereas the 'poor' group, drank milk and ate dairy products (38.0%) as well as fast food and fried food (22.8%). Intakes of energy, fat, vitamins $B_2$ and $B_6$, niacin, folic acid, calcium, iron, zinc, and phosphorus were higher in the 'poor' group. The average hemoglobin level ($13.77{\pm}1.00\;g/dL$) among the subjects was within normal range; while 2.7% of subjects had hemoglobin levels under 11.1 g/dL (standard value) and were examined as anemic. The degree of interest in health was 24.5% higher among the subjects who had poor dietary habits. In contrast, among those who had good dietary habits, 49.6% reported they had no interest in regular exercise. The subjects reported that regular meals, nutrient intake, sufficient rest, and sleep as necessary to maintain health. The average amount of sleep obtained by the subjects was 6~8 hours. Among the 'poor' group, 36.2% reported that they exercised regularly, whereas 18.5% of the subjects in the 'good' group reported regular exercise (p<0.05). In conclusion, it appears necessary to provide nutrition education through teaching and to promote nutrition and health to college women so they can control their individual health status and create practicable dietary plans.

• Journal of the Korean Society of Food Culture
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• v.22 no.6
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• pp.721-741
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• 2007

1. For the types of boiled rice, there were 1 type of bap, 1 type of jebap cooked with glutinous rice, 13 types of boiled rice cooked by mixing grains and nuts such as daemakban, somakban, jobap, cheongryangmiban, jobap, gijangbap, yulmubap, hyeonmibap, boribap and patmulbap as well as patbap, congbap, byeolbap and bambap etc as ogokbap. Also, there were 12 types of bap cooked by mixing herb medicinal ingredients such as cheongjeong, oban, boksungabap, gumeunsaekbap, hwanggukgamchobap, yeongeunbap, okjeongbap, gogumabap, dububap, samssibap, dorajibap, gamjabap, songibap and jukshilbap. There were 7 types bap cooked as unique one bowl dish at the present as bapby mixing fish, meat, shellfish and milk as ingredients are hwangtang, gyejanggukbap, janggukbap, gulbap, kimchibap, chusaban and bibimbap, etc and the types of bap that have been analyzed are 34 total. 2. For the food ingredients used in bap types 23 types of miscellaneous grains, 5 types of nuts and 11 types of meat, 6 types of fish, 35 types of vegetables, 2 types of fruit including pears or peaches were used. Garlic wasn't used perhaps because of it being boiled rice 3. Types of Sap by Cooking Methods. (1) The ssalbap was cooked by first boiling water, putting in rice grains and boiling hard to be cooked as overcooked bap (rice). (2) The japgokbap (boiled cereals) has used buckwheat, barley job's tear, etc to be boiled down by soaking the ones with large grains (beans) first in advance to be boiled down or cooked by crushing into fine pieces. The red bean, etc was boiled down in advance or placed at the bottom of pot by cutting into two pieces while jujube or nut was cut into three pieces to cook the bap by pouring a lot of water and mixing other ingredients. (3) The gukbap (soup boiled rice), etc were cooked by squeezing out the yellow chrysanthemum that has dried chrysanthemum to cook the boiled rice by putting in rice and gukbap, meat or bones, etc were boiled down for a long time and decorated with meat or wild greens by mixing the bap in the meat juice. For gulbap (oyster boiled rice), etc, it was cooked as ingredients were stir fried in advance or washed and put in when the bap was about half cooked. (4) For bibimbap (mixed boiled rice), after the bap was overcooked first with rice, the wild greens were mixed lightly with bap beforehand, then the wild greens, decorations and garnishings were laid above rice and red pepper powder was sprinkled. (5) Namchok leaves, etc were boiled to cook the boiled rice with rice after being cooled while namchok stem and leaves were pounded to make juice and cooked the bap with rice. The peach, lotus root and yams were cut into fine pieces to be put in together when rice was about half done. The bellflower was soaked in water to be boiled down for a long time while potatoes and pine mushrooms, etc were cut into fine pieces to cook the bap (boiled rice) with rice.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.103-134
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• 1977

The physiological and biochemical role of potassium for upland crops according to recent research reports and the nutritional status of potassium in Korea were reviewed. Since physical and chemical characteristics of potassium ion are different from those of sodium, potassium can not completely be replaced by sodium and replacement must be limited to minimum possible functional area. Specific roles of potassium seem to keep fine structure of biological membranes such as thylacoid membrane of chloroplast in the most efficient form and to be allosteric effector and conformation controller of various enzymes principally in carbohydrate and protein metabolism. Potassium is essential to improve the efficiency of phoro- and oxidative- phosphorylation and involve deeply in all energy required metabolisms especially synthesis of organic matter and their translocation. Potassium has many important, physiological functions such as maintenance of osmotic pressure and optimum hydration of cell colloids, consequently uptake and translocation of water resulting in higher water use efficiency and of better subcellular environment for various physiological and biochemical activities. Potassium affects uptake and translocation of mineral nutrients and quality of products. potassium itself in products may become a quality criteria due to potassium essentiality for human beings. Potassium uptake is greatly decreased by low temperature and controlled by unknown feed back mechanism of potassium in plants. Thus the luxury absorption should be reconsidered. Total potassium content of upland soil in Korea is about 3% but the exchangeable one is about 0.3 me/100g soil. All upland crops require much potassium probably due to freezing and cold weather and also due to wet damage and drought caused by uneven rainfall pattern. In barley, potassium should be high at just before freezing and just after thawing and move into grain from heading for higher yield. Use efficiency of potassium was 27% for barley and 58% in old uplands, 46% in newly opened hilly lands for soybean. Soybean plant showed potassium deficiency symptom in various fields especially in newly opened hilly lands. Potassium criteria for normal growth appear 2% $K_2O$ and 1.0 K/(Ca+Mg) (content ratio) at flower bud initiation stage for soybean. Potassium requirement in plant was high in carrot, egg plant, chinese cabbage, red pepper, raddish and tomato. Potassium content in leaves was significantly correlated with yield in chinese cabbage. Sweet potato. greatly absorbed potassium subsequently affected potassium nutrition of the following crop. In the case of potassium deficiency, root showed the greatest difference in potassium content from that of normal indicating that deficiency damages root first. Potatoes and corn showed much higher potassium content in comparison with calcium and magnesium. Forage crops from ranges showed relatively high potassium content which was significantly and positively correlated with nitrogen, phosphorus and calcium content. Percentage of orchards (apple, pear, peach, grape, and orange) insufficient in potassium ranged from 16 to 25. The leaves and soils from the good apple and pear orchards showed higher potassium content than those from the poor ones. Critical ratio of $K_2O/(CaO+MgO)$ in mulberry leaves to escape from winter death of branch tip was 0.95. In the multiple croping system, exchangeable potassium in soils after one crop was affected by the previous crops and potassium uptake seemed to be related with soil organic matter providing soil moisture and aeration. Thus, the long term and quantitative investigation of various forms of potassium including total one are needed in relation to soil, weather and croping system. Potassium uptake and efficiency may be increased by topdressing, deep placement, slow-releasing or granular fertilizer application with the consideration of rainfall pattern. In all researches for nutritional explanation including potassium of crop yield reasonable and practicable nutritional indices will most easily be obtained through multifactor analysis.