• Journal of Microbiology and Biotechnology
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• 제16권1호
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• pp.5-14
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• 2006

Streptomycetes are Gram-positive microorganisms producing secondary metabolites through unique physiological differentiation [4]. The microbes show unusual morphological differentiation to form substrate mycelia, aerial mycelia, and arthrospores on solid medium [19]. Substrate mycelium growth is sustaining with sufficient nutrients in the culture medium. The concentration of a specific individual substrate in the culture environment is the most important extracellular factor allowing vegetative mycelia growth, where extracellular hydrolytic enzymes participate in the utilization of waterinsoluble substrates. However, with starvation of nutrients in the culture medium, the vegetative mycelia differentiate to aerial mycelia and spores. It has been considered that shiftdown of essential nutrients for mycelia growth is the most important factor triggering morphological and physiological differentiation in Streptomyces spp. Since proteineous macromolecule compounds are the major cellular components, these are faced to endogenously metabolize following a severe depletion of nitrogen source in culture nutrients (Fig. 1). Various proteases were identified of which production was specifically related with the phase of mycelium growth and also morphological differentiation. The involvement of proteases and protease inhibitor is reviewed as a factor explaining the mycelium differentiation in Streptomyces spp.

• Journal of Nutrition and Health
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• 제37권10호
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• pp.917-927
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• 2004

This study was performed to examine component of variance in nutrient intakes and to estimate the level of accuracy with varying degree of precision in order to achieve estimates of usual nutrient intakes. Three-day dietary records including both weekdays and weekends were collected every 4 season over a I-year period from 36 males and 93 females aged 40 - 65 y. For each nutrient, we partitioned total intake variance into weekly (weekday vs weekend), seasonal, within- and between- individual variation as components of variance, using analysis of variance. It was found that major components of variance were within- and between-individual variation. Particularly, within-individual variation (57.2 - 87.1 %) was greater than between-individual variation (12.2 - 37.4%) for all nutrients. Weekly and seasonal variation contributed small components of variance for most nutrients. For protein, fat and carbohydrate, there were a little significant weekly variation (0.00 - 1.35%) in females but not in males. For some micronutrients, there were moderately significant seasonal variation (0.15 - 5.48%) in both sexes. Ratio of within- to between- individual variation ranged 1.4 (vitamin B$_2$) -4.5 (vitamin B$_1$) in males and 1.6 (carbohydrate) -2.9 (fat) in females. With total 12-day dietary records data, the maximum percentage deviation of observed intakes from usual (true) intakes ranged 12-37%. To estimate usual individual intakes within 20% of the true mean with 90% confidence level, 3 - 9 days of dietary survey were required for energy, protein, carbohydrate, phosphorus and iron, 13 - 19 days for fat and calcium, 25 - 29 days for vitamin A and vitamin C. Correlation coefficients between observed and true nutrient intakes were 0.71 - 0.91 for males, 0.81-0.91 for females. In conclusion, mean intakes of several nutrients can be reliably measured with the record method, using a limited number of days. Both nutrients of interest and the primary objectives should be taken account when planning method of assessment and number of replicates.

• 대한지역사회영양학회지
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• 제2권4호
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• pp.624-632
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• 1997

This study was conducted to evaluated the nutrition quality of the commercial supplementary foods for infants and young children and to seek a solution to the establishment of standards of nutrient requirements for supplementary foods in Korea. Information on food ingredients, nutrient contents, claims about usefulness of food components and instructions for feeding preparation were obtained from the labels of 33 commercial supplementary foods manufactured by 4 different domestic companies. According to the standard of supplementary foods for infants and young children described in the Korean Food Code, the commercial supplementary foods were categorized into two different types, weaning food and baby food. All the commercial weaning foods were in powder form and mainly composed of cereals, whereas all the baby foods were mainly composed of fruits in the form of canned juice. The weaning foods contained more nutrients than the baby foods did, and the nutrient levels of the weaning foods expressed as nutrient density on energy basis were higher than the RDA for infants aged 5 to 11 months, suggesting that the commercial weaning foods provide adequate amounts of nutrients. If one followed the instructions for feeding preparation appearing on the label, however, recommended amounts of intake of the weaning foods would provide too much energy as well as nutrients. There were many differences in nutrient standards of weaning foods between the Korean Food Code and Codex international food standard. In conclusion, the establishment of standards for nutrient requirements for the supplementary foods requires significant scientific studies on what nutrients are the most inadequate in Korean infants and young children feeds and what levels of nutrients should be added to the foods in order to supplement their nutrition. In addition, it is very important to have a strong scientific basis to support our standard when discrepancies exist between our standard and the international standard. (Korean J Community Nutrition 2(4) : 624-632, 1997)

• 한국초지조사료학회지
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• 제21권1호
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• pp.7-14
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• 2001

신개간 산지초지의 정착, 목초의 수량제고 및 품질향상 등에 미치는 초지조성비 비종별 시비효과를 구명하고, 초지조성 및 유지관리에 비효가 높은 적합한 비료를 선택하고자 미개간 산지토양을 공시한 pot 시험으로 기초실험을 수행하였다. 공시된 초지 조성비 3요소 비료처리구는 1) 무비구, 2) 요소-중과석-염가, 3) 요소-용성인비-염가 및 4) 3종 복비로 하였다. 본보에서는 무기양분 및 일반성분의 함량 및 양분수량(탈취량)을 검토하였다. 1. 무기양분의 함량에서는 복비구가 orchardgrass, ladino clover 및 이들의 혼합목초 공히 N, P. Ca, Mg, Na 함량이 중과석 및 용인구보다 상대적으로 높았다. 초종별 무기양분 수량(발취량)은 일반적으로 3종 복비>용인>중과석 시비주 순으로 높았고, ladino clover와 혼합목초에서 3종 복비 시비효과가 더 크게 나타났다. 2. 일반성분 함량은 3종 복비 시비구가 각 구성 초종 공히 조단백질 및 조회분 함량이 중과석과 용인구보다 높았으며. 각 일반성분의 양분수량은 구성 초종에서 ladino clover 및 혼합목초에서는 3 종 복비구가 월등히 높았다. 반면에 orchardgrass 목초에서는 비종에 따라 다소 차이를 보였다. 일반적으로 3종 복비>용인>중과석 시비구 순으로 건물수량, 양분 함량 및 양분수량 등에서 양호한 특성을 보였다.

• 한국지역사회생활과학회지
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• 제15권3호
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• pp.57-61
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• 2004

Many studies have presented results about the antioxidative and antimicrobial activities of Dandelions (Taraxacum officinale). There has yet to be a study which makes comparisons of nutrients based on the parts of the Dandelion. To identify the nutrient composition by part of dandelion, nutrient contents were analyzed. Dandelions were taken from Songpa-gu in Seoul and the nutrient composition of the flower, leaf and root were measured. The nutrient content of each part was analysed by using the method developed by the Association of Official Analytical Chemists (AOAC). The proximate components(moisture, protein, fat, fiber, ash, and carbohydrates), minerals and vitamins of the dandelion were analysed. The nutrient composition of the dandelions showed many significant differences among the parts when the differences were determined by using Duncan's multiple range test. The leaf contains more protein, ash, Ca, K, Mg, Zn, vitamin A, B$_1$, B$_2$, and C than the other parts. The root has much more fiber, carbohydrate, P and Fe content. The results demonstrate that dandelions could be used as a food source supplement for fiber, Ca, Fe and vitamin B$_2$ which are common nutritional deficiencies in Korea. It is recommended that more research for other bio-functional factors besides nutrients composition is needed to enhance the utilization of the dandelion.

• Journal of Nutrition and Health
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• 제30권3호
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• pp.349-359
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• 1997

This study was designed to study sources of variability(subjects, day by day, season, day of week, sequence, number of repeated days, compliance etc.) in multiple 24-hour dietary recall method. Dietary intakes of college women in Seoul were obtained using 24-hour dietary recalls, consecutive 7 days, 4 times for 1 year. The result of this study shows that 1) the reproducibility of multiple 24-hour recalls is low(intraclass correlation coefficient<0.3), 2) the intraindividual variations of all nutrients are more than 80%, 3) the major components of variation are interindividual vriability and intraindividual variability(within person variability and methodologic error). There were small but statistically significant season and compliance effects. 4) the ratio within-person varation to between-person variation for absolute and transformed nutrient intakes except some nutrients such as vitamin A, vitamin C, energy from protein and fat etc, was less than 1.7 the minimum numbers of days needed in 24-hour dietary recalls to estimate usual intake for this group were 1 to 21 days. And the numbers of days needed to get the usual intake of an individual varied among individuals and within individuals for different nutrients, ranged from 1 days for log carbohydrate(% energy) to 470 days for Na. 6) There were greater than 0.7 correlation coefficients between the average nutrient intakes of 12 days and intakes of 28 days. Therefore, it was desirable to take the 24-hour recall more than 12 times, repeating 3 days every season.

• 한국자기공명학회논문지
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• 제26권3호
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• pp.24-33
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• 2022

The browning phenomenon of fruits can be easily observed when fruits or vegetables (apples, pears, bananas, potatoes, etc.) are cut with a knife and the part turns brown. When this browning occurs, changes in taste, color, and nutrients usually are introduced. The cause of this browning phenomenon has been well studied for a long time, but these studies have mainly focused on preventing deterioration of processed foods during food processing or storage. Resultantly, there are few studies on how much changes in nutrients (saccharides, amino acids, fats, water-soluble low molecular weight ammonium ions, etc.) are caused by browning. The purpose of this study is to determine the change in nutrients during browning using apple as a model fruit. We conducted a comparative study on how much the nutrient fluctuations differ depending on the presence or absence of pretreatment such as the application of heat. All analysis was conducted using ¹H NMR. The ANOVA analysis showed that the concentrations of 4 amino acids (alanine, asparagine, isoleucine, and valine), 3 types of sugars (fructose, glucose, and xylose), 1 type of organic acid (lactate) and choline were significantly increased in samples showing browning. In addition, the groups before and after browning were clearly separated using multivariate statistical analysis methods (PCA, PLS-DA), which was greatly contributed by two sugar components (fructose and glucose) present in high concentrations in apples.

• Journal of Dairy Science and Biotechnology
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• 제19권1호
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• pp.39-48
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• 2001

As the development of medical technology and the elevation of the standard of living, the population rate of elderly people in Korea is increasing gradually. To keep a good lift quality of the elderly, both appropriate exercise and nutrients intake are necessary for them. Dairy products are known for the good source of variable nutrients including functional components and bioactive peptides such as Ig, lactoferrin, MFGM, OPP, CPP, GMP, sialic acid etc that are required especially for elderly people. However, they are classified as the low dairy products consumption group recently. For the promotion of dairy product consumption of elderly people, variable and specialized dairy products for the elderly should be researched and developed with the strengthened publicity activities.

• 한국식생활문화학회지
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• 제11권4호
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• pp.507-515
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• 1996

Television food advertisement is the most effective way to reach to consumers with food and nutritional informations and affect their eating behavior. Therefore, 218 food commercials were reviewed using video tapes and copies to know the present food product trends, food messages they transmit and define misleading food commercials. Messages were focused on the benefit of health promoting substances they contain, especially for functional food components, fortified nutrients, food safety focused on food additives, convenience and differentiation with other products. Overnutrition on specific nutrients could be expected due to nutrient fortified products and misleading of food commercials were also noted. Regarding trends, guidelines provided by television broadcasting company shoud be fortified in the connection of Food Hygine Law and supervision committe should reinforce the food company to summit data for the approval of their advertisement claims. Nutrition educational spot program shoud be produced and broadcasted for the public to protect the consumer from food faddism in near future.

• 한국식품영양과학회지
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• 제19권2호
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• pp.133-142
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• 1990

This study was attempted to compare the nutritive value of leaf with stem of the water cress Oenanthe stolonifera DC. in order to improve the eating habits and as a part of studying on the effective curing nutrients for the damaged liver. The contents of moisture crude proteinon the effective curing nutrients for the damaged liver. The contents of moisture crude protein crude fat and crude ash were 90.40% 2.85%, 0.42% and 0.74% in leaf while the contents of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09%, and 0.64% of moisture crude protein crude fat and crude ash were 95.15% 0.77% 0.09% and 0.64% in stem respectively. The quantitative fractionation of proteini of both leaf and stem ranked albumin the highest content followed globulin prolamin and glutelin in order. It has been sh-own by SDS-polyacrylamide gel electrophoresis that water extractable protein of leaf 11 bands but those of stem were not detected. The scope of molecular weight for the main protein of water extractable protein of leaf was between 34.700 and 45,000. The amounts of extractive-nitrogen from leaf and stem of the water cress were 241.02mg% and 271.67mg% respec-tively. The amounts of free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid-nitrogen from the leaf and stem were 89.02mg% and 32.02mg% respectively. In free amino acid composition of both leaf and stem the major components were aspartic acid and glutamic acid. In total amino acid composition of water cress leaf aspartic and glutamic acid were the major components. Whereas alanine and thr-eonine were the major components in stem The assessment of water cress leaf and stem with chemical score. EAAl Rl showed that the values of stem were lower tendancy than those of leaf. Limiting amino acid of leaf was tryptophan while that of stem was lysine.