• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2180-2189
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• 2017

Psychrophilic phytases suitable for aquaculture are rare. In this study, a phytase of the histidine acid phosphatase (HAP) family was identified in Morchella importuna, a psychrophilic mushroom. The phytase showed 38% identity with Aspergillus niger PhyB, which was the closest hit. The M. importuna phytase was overexpressed in Pichia pastoris, purified, and characterized. The phytase had an optimum temperature at $25^{\circ}C$, which is the lowest among all the known phytases to our best knowledge. The optimum pH (6.5) is higher than most of the known HAP phytases, which is fit for the weak acidic condition in fish gut. At the optimum pH and temperature, MiPhyA showed the maximum activity level ($2,384.6{\pm}90.4{\mu}mol{\cdot}min^{-1}{\cdot}mg^{-1}$, suggesting that the enzyme possesses a higher activity level over many known phytases at low temperatures. The phytate-degrading efficacy was tested on three common feed materials (soybean meal/rapeseed meal/corn meal) and was compared with the well-known phytases of Escherichia coli and A. niger. When using the same amount of activity units, MiPhyA could yield at least $3{\times}$ more inorganic phosphate than the two reference phytases. When using the same weight of protein, MiPhyA could yield at least $5{\times}$ more inorganic phosphate than the other two. Since it could degrade phytate in feed materials efficiently under low temperature and weak acidic conditions, which are common for aquacultural application, MiPhyA might be a promising candidate as a feed additive enzyme.

• Korean Journal of Community Nutrition
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• v.4 no.2
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• pp.207-218
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• 1999

The increased number of elderly in Korea presents great challenges for community nutrition programs. Strategies to enhance elderly nutrition are needed, as well as dietary advice that are reality-based and tailored to the need of the elderly. The purpose of this study was to evaluate the overall effectiveness of an elderly nutrition improvement program(ENIP), by assessing changes in nutrition knowledge, attitudes, and behavior after program completion. ENIP was conducted in Suwon for 4 months in 1998 at 5 centers for the elderly. The program provided individual nutrition counseling and brief biweekly group education sessions. To stimulate participation and motivation, the elderly in two centers were served free milk packs(200ml) three time a week during the program(milk＋education group), and the elderly in 3 other centers were served yoghurt on the program day(education group). Altogether, 102 subjects finished the program(milk＋education group 67 ; education group 35). Data about nutrition knowledge, dietary attitudes, diet records(24 hour recall) and dietary habit was collected before(baseline) and after the program(follow-up). The Drop-out rate for the milk＋education group(2.9%) was significantly lower than that for the education group(30.0%)(p<.001). The Nutrition Knowledge fo females milk＋education group increased significantly after the program, but no significant differences were observed in other groups. Over 60% of all the elderly showed positive responses to the healthy eating attitudes. Energy, protein, vitamin A, riboflavin, Calcium and Potassium intakes improved in the male milk＋education group. The Vitamin C intake improved in the male education group. Energy and vitamin A intakes improved in the female milk＋education group and energy, vitamin A, thiamin, riboflavin, niacin, Ca nad P in the female education group. A stepwise multiple regression analysis was performed to examine the effects of food intake changes on overall nutrient quality. For all elderly, the fish intake explained 12.6% of the variance, followed by candy intake and vegetable intake(model $R^2$=19.6%). Dietary habits such as meal time regularity and salty food reduction were markedly improved in both groups. Sixty-one percent of the milk＋education subjects stated their participation was voluntary and active, while 51% of education subjects did. Sixty four percent of the subjects stated their interest on diet increased remarkably through program participation. Considering the results, it is conjectured that ENIP had a great impact on nutrient intake, dietary attitudes and habits. Milk supplement showed no direct effects on elderly nutrition improvement, but it encouraged the program by reducing drop-out rates and inducing voluntary participation. Therefore milk supplement could enhance the community nutrition education program. Moreover it is strongly suggested that the ENIP be expanded to other communities.

• Journal of Nutrition and Health
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• v.35 no.2
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• pp.250-262
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• 2002

This study was conducted to develop a simple flood frequency questionnaire (FFQ) based on the results of contributions of specific floods to absolute intake and between-person variance in nutrients using semi-quantitative FFQ with 93 flood items. The subjects were 554 healthy adults for development of a simple FFQ, and 37 students for a validation test of a developed simple FFQ. The contribution of specific floods to 80% absolute nutrient intake was measured by assessing their percentage in total consumption of a nutrient. To assess the contributions of floods to the between-person variance in the intake of each specific nutrient, stepwise multiple regressions were performed. The number of floods necessary to account for the respective 80% of absolute intake was 11-36, depending on the nutrient, while flower floods (5-16 floods) were required for the corresponding percentage of between-person variation for all nutrients. Important floods for between-person variance include Tangsuyuk (pork) and snacks for energy and fat, fish for protein and polyunsaturated fatty acids (PUFA) and snacks for carbohydrates. Spearman correlation coefficients between 93-itemed FFQ and 63-itemed FFQ ranged from 0.91 for vitamin A to 0.99 for fat in the population data used in developing a simple FFQ. Also, the correlation coefficients between the two FFQs were 0.82-7.92 in the population for the validation test. This study suggests that useful information on dietary intake could be obtained using a simple semi-quantitative FFQ in a large-scale dietary survey in Korea.

• Culinary science and hospitality research
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• v.18 no.1
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• pp.15-26
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• 2012

The objective of this study is to optimize enzymatic hydrolysis of cooked krill by using Alcalase. To optimize krill hydrolysis on such dependent variables as TCA, DPPH-scavenging, and Fe-chelating activities by using Alcalase, independent variables of hydrolysis pH and temperature were investigated Their formulas and three dimensional graphs were obtained by using SAS and Maple softwares, respectively. For comparison of general composition of raw krill, its contents of moisture, crude protein, crude fat, and ash were 17.48%, 53.74%, 15.66%, and 10.21%, respectively, and for cooked krill, its contents were 4.80%, 71.84%, 5.26%, and 15.09%, respectively. The composition of fatty acids for cooked krill was similar to that of raw krill. The most abundant fatty acid was palmitic acid(16:0) and the following order was oleic acid(18:1), eicosapentaenoic acid (20:5), palmitoleic acid(16:1), and docosahexaenoic acid(22:6). For DH optimization of hydrolysates from cooked krill, its result was pH 8.5 and $66.6^{\circ}C$ hydrolysis temperature for the maximum DH of 29.4% For DPPH-antioxidative optimization of hydrolysates from raw krill, its maximum result of 27.1% was obtained in the hydrolysis condition of pH 7.4 and $67.5^{\circ}C$. For Fe-chelating optimization of hydrolysates from cooked krill, its maximum result of 24.9% was in the condition of pH 8.7 and $65.5^{\circ}C$. These results can be used for basic data for using krill products and other fish products as bioactive ingredients.

• Korean Journal of Community Nutrition
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• v.10 no.6
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• pp.952-962
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• 2005

To explore the relationship between economic status and food and nutrient intake patterns, the 2001 National Health and Nutrition Survey result was analyzed. Dietary intake data of 6,978 Korean adults of 20 years and older who participated in the 2001 National Health and Nutrition Survey were used along with their demographic data. Economic status of the subjects was classified into the following 4 groups based on the self-reported average monthly income of household with reference to the minimum monthly living expenses (MLE) in 2001 : low < $100\%$ MLE $\leq$ middle < $200\%$ MLE $\leq$ high < $300\%$ MLE $\leq$ higher, Individuals in the higher income class had significantly higher mean intake for most of the nutrients including energy, protein, carbohydrate, fat, calcium, thiamin, riboflavin, niacin and vitamin C, and a higher percentage of energy intake from fat. In addition, they consumed more animal foods including meats, eggs, fish/shellfish, milk/dairy products and fats. On the other hand, the mean intakes of individuals in the lower economic class for calcium, vitamin A, and riboflavin were lower than $75\%$ of RDAs. And, there was a predominant difference in contribution of fat to total energy intake among the groups of different economic status. These results showed that household income is an important factor influencing the food and nutrient intake patterns of the Korean adult population. Although individuals at different age classes may respond differently to a change in economic status, developing and implementing nutrition policy and intervention programs for those nutritionally vulnerable groups should consider the economic status as an important factor to customize and differentiate the content of the Program. (Korean J Community Nutrition 10(6) : $952\∼962$, 2005)

• Journal of Life Science
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• v.22 no.6
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• pp.788-793
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• 2012

High concentration of antibiotics has been used to treat the outbreak of edwardsiellosis caused by Edwardsiella tarda in aquaculture. However, not all of the bacteria have been killed with high concentrations of antibiotics treatment by the formation of persister cells with a dormant state. The main objective of this study was to kill persister cell using antibiotics with the addition of natural plant compounds. Antibiotics used in this study consist of 100 mg/ml florfenicol and 100 mg/ml amoxicillin. Ten natural plant compounds with persister cell inhibitor activity to E. coli were obtained from Protein Engineering and Systems Biology Lab. of Sungkyunkwan University. The persister cell inhibition activities of those natural plant compounds were evaluated in test tube. Concentrations of the antibiotics were in the ranges of 25~200 ${\mu}g/ml$. The persister cell formation was observed after 16 hours of culture. Persister cells were killed by antibiotics with natural plant compounds. Among ten natural plant compounds, Gynostemma pentaphyllum, Mallotus japonicus, and Orixa japonica showed persister cell formation inhibition activities. The optimal concentrations of G. pentaphyllum, M. japonicus, and O. japonica for the inhibitor of persister cell formation were 100 ${\mu}g/ml$, 100 ${\mu}g/ml$, and 200 ${\mu}g/ml$, respectively. In vivo study was carried out to evaluate the effect of the antibiotics with natural plant compounds using aquacultural fish, olive flounder, as test animals. G. pentaphyllum, M. japonicus, and O. japonica of 30 ${\mu}g/ml$, 10 ${\mu}g/ml$, and 10 ${\mu}g/ml$ with antibiotics reduced cumulative mortalities, showing the effectiveness of persister cell inhibition.

• Journal of Life Science
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• v.27 no.1
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• pp.50-56
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• 2017

An antibacterial peptide was purified from an acidified gill extract of the pufferfish Takifugu pardalis. The acidified gill extract was put through a Sep-Pak C18 solid phase extraction cartridge using a stepwise gradient and divided into a flow-through (F.T.) and 60% methanol fraction (RM 60). Among the eluents, RM 60 had potent antibacterial activity against Bacillus subtilis KCTC 1021. RM 60 was partially purified on a cationic-exchange column (SP-5PW) by a linear gradient, and the antibacterial peptide was then further purified, using a series of cationic-exchange and $C_{18}$ reversed-phase HPLC columns. For characterization of the purified peptide, its molecular weight and amino acid sequence were analyzed by MALDI-TOF MS and Edman degradation. The molecular weight of the peptide was about 1171.6 Da. The amino acid sequence of the peptide was partially determined as: STKEKAPRKQ. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high homology with the N-terminus of the histone H3 protein, which belongs to the histone H3 family. Thus, this peptide was designated as a puffer fish gill (PFG)-related antimicrobial peptide. This is the report to describe an antimicrobial function for the N-terminus of histone H3 of an animal species. The findings suggest that this peptide plays a significant role in the innate defense system of the pufferfish.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.669-677
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• 2009

The purpose of this study was to compare the anthropometry, nutrient intakes, dietary - related behaviors and health - related behaviors of male workers that were divided according to their alcohol consumption. The mean height, weight and BMI of all subjects were 172.0$\pm$5.8 cm, 67.8$\pm$9.3 kg and 22.9$\pm$2.6 kg/$m^2$, respectively. The WHR was higher in the heavy drinking group than in the other groups(p<0.01), while the other anthropometric indices were not significantly different among the three groups. The calorie intake was highest(p<0.001) in the heavy drinking group(3,270.4$\pm$686.5 kcal), followed by moderate(2,602.8$\pm$415.8 kcal) drinking group and light drinking group(2,341.5$\pm$449.4 kcal). As alcohol consumption increased, there was a decrease in the percent of energy derived from carbohydrates and lipids, while there was an increase in the percent of energy derived from proteins and alcohol(p<0.001). The heavy and moderate drinking groups had a highers intake of protein compared to the light drinking group, and the heavy drinking group had a higher intake of lipid compared to the light and moderate drinking groups(p<0.01). The intakes of vitamin $B_2$, niacin and phosphorus were lower in the moderate group than the other groups(p<0.01). The average MAR(Mean adequacy ratio) was 1.44$\pm$0.35 and the intake of all nutrients, except for folic acid, was much higher than the Korean RI(Recommended intake). The fruit intake frequency and sleeping hours were the lowest in the heavy drinking group(p<0.05) and the subjects preferred the following order of food products when they drink: meat(42.5%), fish & shellfish(30.0%), fruit & vegetable(22.5%) and others(5.0%) as a side dish. The average rates of smoking and exercise for all the subjects were 77.5% and 67.5%, respectively. The results of this study showed that heavy alcohol drinkers were more prone to abdominal obesity and related chronic degenerative diseases, indicating the need for extensive nutritional education for heavy alcohol drinkers.

• Journal of Nutrition and Health
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• v.10 no.1
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• pp.49-58
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• 1977

Nutrition counselors in Korea often encounter difficulty in their attempt to change village women's attitudes regarding food taboos which are counter to good eating habits. There are a great many food superstitions which are not due to religious influence, but seem to be related to shape and composition of food. Many expectant mothers superstitiously avoid eating certain foods for fear that they may cause mental or physical abnormality in their babies. As was shown in a previous survey (Mo, 1966)of villages in all provinces except Jeju Island, such superstitions were common among pregnant and lactating mothers. Many food taboos and superstitions based on non-scientific and irrational ideas do exist even in modern society, and are a major obstacle to nutritionally adequate food consumption. A study of food taboos among women of Jeju Island was undertaken from November to December of 1976, these results to be compared as well with those of the previous study. There were 73 items found to be prohibited during pregnancy. Of these, 48.7% were of the deaf group, 17.4% fish, 5.5% eggs, 4.7% cereal, and only 2.2% fruit. Of 252% women respondents, 111 (45% ) abstained from eating chicken, duck, and shark because of the belief that they would cause their babies to be born with gooseflesh or shark skin. Many of them avoided rabbit meat for fear that their babies might be born with harelip. It was also feared that a baby would become disfigured if his mother ate duck, goat, dog meat, chicken or duck eggs, or soup made of bones. A common superstition was that highly spiced or salty foods would cause the fetus to be hairless. Squid and octopus were believed to cause babies to have weak bones, or none at all. Most of these food taboos were associated with fears concerning Physical structure and appearance of unborn babies. Other taboos were associated with fear of undesirable behavioral characteristics. For example, some mothers thought that a baby would pinch or bite the mother's breast during the weaning period, if crab meat were eaten during pregnancy. Unevenly sliced rice cake, loach, snake meat and eel were also believed to cause a baby to be ill-tempered. The findings of this study are remarkably similar to those of the previous study conducted by the authour in 1966. Most of the same food taboos, based on non-scientific and irrational reasons, were found on Jeju Island as on the peninsula, and thor were similarly wide-spread. The results of correlational analysis show that the most significant factors related to prevalence of food taboos, are level of education and religious background. Number of food taboos is correlated with level of education. Also, food taboos are least freqent among the Christian woman. Proper nutrition education should he undertaken in order to encourage intake of protein-rich food, particularly during pregnancy when nutritional needs of mother and fetus are great.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.259-264
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• 1994

The possibility of shellfish utilization of juice as seasoning materials was examined through the analyzing proximate compositions and N-containing materials. The amounts of the sucking liquid wastes were estimated as 58,819 tons for oyster, 764 tons for pen-shell, 604 tons for cockle and 3,896 tons for blue-mussel from 1985 to 1990 in Korea. Water contents ranged from 95.2 to $97.4\%$ and crude protein level was $1.0{\sim}1.4\%$. Taurine was the most abundant nitrogenous compound($40{\sim}56\%$) in extracts, and glycine($10.4{\sim}36.1\%$), alanine($4.8{\sim}8.6\%$) and glutamic acid($3.1{\sim}5.3\%$) followed. More than $40\%$ of ADP and AMP as mucleotide were contained in all shellfish samples but pen-shell and cockle had $20\%$ of inosine, also. Glycinebetaine was present in corcentrations of 139.8mg/g in oyster and $45.5{\sim}61.9mg/100g$ in pen-shell, cockle and blue-mussel. Total creatinine and trimethylamine oxide levels were $30.4{\sim}59.1mg/100g$ and $0.82{\sim}47.2mg/100g$, respectively.