• Microbiology and Biotechnology Letters
• /
• v.11 no.1
• /
• pp.5-13
• /
• 1983

This experiment was carried out to elucidate the thermotolerant properties of a thermophilic bacterium which isolated from soils of the hot springs area and selected for the $\beta$-galactosidase production. Biochemical and physiological characteristics of this strain were studied, including the investigation on the fatty acid composition for its neutral fats. The results obtained were summarized as follows. 1. This bacterium was identified as a strain belong to the genus Thermus. 2. Optimal temperature and pH for growth of this strain were $65^{\circ}C$ and pH 6.5 respectively, and it was found to be an absolute thermophilic bacterium which could not grow at 37$^{\circ}C$. 3. No growth was obtained in the medium which contained more than 1.0% of sodium chloride. 4. The tolerable concentration of antobiotics were 10$\mu\textrm{g}$ of penicillin G per $m\ell$ of medium and 0.5$\mu\textrm{g}$ of chloramphenicol per $m\ell$ respectively 5. This strain had autotrophilic requirements for calcium-pantothenate and pyridoxine-HCO as an-essential factor and for niacin as a stimulative factor. 6. Fatty acid composition of neutral fats of the strain was palmitic acid. 60.20%; lauric acid, 11.8%; myristic acid, 7.56%, behenic acid, 4.25%; capric acid, 1.77%; stearic acid, 2.13%; arachidic acid, 1.53%; and others unidentified, 10.7%.

• Korean Journal of Agricultural Science
• /
• v.9 no.1
• /
• pp.377-386
• /
• 1982

This experiment was carried out to elucidate the thermotolerant properties of a thermophilic bacterium which was isolated from soils of the hot springs area and selected for the ${\beta}$-galactosidase production. This bacterium was identified as a strain belong to the genus Thermus. Biochemical and physiological characteristics of this strain were studied, including the investigation of the fatty acid composition of its neutral fats. The results obtained were summarized as follows. 1. Optimal temperature and pH for growth of this strain were $65^{\circ}C$ and pH 6.5 respectively, and it was found to be an absolute thermophilic bacterium which could not grow at the temperature below $43^{\circ}C$. 2. No growth was obtained in the medium which contained more than 1.0% of sodium chloride. 3. The tolerable concentration of antibiotics were 10mg of penicillin G per ml of medium and 0.5mg of chloramphenicol per ml respectively. 4. This strain had auxotrophilic requirements for calcium-pantothenate and pyridoxin-HCl as an essential factor and for niacin as a stimulative factor. 5. Yellow pigment was released into the liquid culture of this strain, which showed maximum absorption at 420 nm. 6. Fatty acid composition of neutral fats of the strain was palmitic acid, 60.20%; lauric acid, 11.80%; myristic acid, 7.56%; behenic acid, 4.25%; capric acid, 1.77%; stearic acid, 2.13%; arachidic acid, 1.53%; and others unidentified, 10.7%.

• Journal of Nutrition and Health
• /
• v.40 no.4
• /
• pp.371-384
• /
• 2007

This study was conducted to examine nutrient intake status and iron food sources by dietary iron density of high school girls in Seoul. The subjects of 226 girls were divided into High group (${\geq}$ 6 mg/1,000 kcal, N=115) and Low group (< 6 mg/1,000 kcal, N=111) by dietary iron density. The nutrient intake data obtained by 24-hour recall method were analyzed by Can Pro 3.0 software. Mean age of all subjects was 16.4 years old, heights and weights of High group and Low group were 164.5 cm, 53.4 kg and 161.7 cm, 51.7 kg, respectively. The body mass index (BMI) of High group and Low group was 20.5 kg/m$^2$ and 19.8 kg/m$^2$, respectively. Most nutrient intakes except energy and lipid intakes of High group were higher than those of Low group. High group showed significantly higher intakes of total iron, vegetable iron and animal iron than Low group. Ca and folate intakes of High group were under 75% of the recommended intake (RI) and Ca, iron, folate and vitamin C intakes of Low group were under 65% of RI. The percentage of subjects who consumed iron less than estimated average requirements (EAR) were 40.0% in High group and 77.5% in Low group. Total food intakes of High group showed higher than that of Low group. Total animal food intakes were significantly higher and total vegetable food intakes were significantly lower in Low group than those of High group. Iron intake from meats, fishes, shell fishes and seasonings were significantly higher in High group than Low group. Iron intake from milk and dairy products were significantly lower in High group than Low group. Major food sources of iron were rice, bean curd, pork, and egg in order among both groups.

• Journal of Nutrition and Health
• /
• v.50 no.4
• /
• pp.376-382
• /
• 2017

Purpose: The consistent rise in the number of foreign students in Korea demands an accurate and detailed investigation into their dietary practices and nutritional status. For these international students, assimilation into new cultures can be stressful. The influence this process may have on dietary behaviors as well as overall health cannot be overlooked. Methods: The researchers in this study sought to investigate the nutritional status and dietary practices of Ghanaian students studying in Korea. A total of 81 Ghanaian male students with an average age of $29.4{\pm}4.0years$ were sampled between May and June 2016. Investigations were carried out on the general characteristics of the participants, their daily food and nutrient intakes using a 24-h dietary recall method, meal skipping practices, and the nutritional quality of their diets based on their meal skipping habits. Results: The study revealed that the daily nutrient intake of subjects did not fully meet the daily recommended nutrient intake (RNI) established by Ghanaian Ministry of Health and the World Health Organization (WHO) and Food and Agriculture Organization (FAO), particularly for energy, calcium, iron, zinc, and vitamin B2 requirements. The Nutrient Adequacy Ratio (NAR) for calcium was very low, posing a deficiency risk to the participants. Meal skipping practices among participants changed significantly after arriving in Korea. The study also compared the diet quality indicators (Nutrient Adequacy Ratio and Mean Adequacy Ratio) of those who skipped meals ${\geq}7times/week$ with those who skipped meals < 7 times/week. Participants who skipped meals ${\geq}7times/week$ were shown to have lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Conclusion: Ultimately, the study found that meal skipping among Ghanaian students was common, and their daily nutrient intakes did not meet the set dietary standards. Those who skipped meals ${\geq}7times/week$ had lower dietary intakes of vitamins B1 and B2 than those who skipped meals < 7 times/week. Based on our study findings, we recommend that nutrition education should be organized for the Ghanaian student community in Korea using our results as a template to draw up a nutrition program that is culturally appropriate.

• Journal of Nutrition and Health
• /
• v.55 no.3
• /
• pp.330-347
• /
• 2022

Folate, a water-soluble vitamin, acts as a coenzyme for one-carbon metabolism in nucleic acid synthesis and amino acid metabolism. Adequate folate nutritional status during the periconceptional period is known to prevent neural tube defects. In addition, insufficient folate intake is associated with various conditions, such as anemia, hyperhomocysteinemia, cardiovascular disease, cancer, cognitive impairment, and depression. This review discusses the rationale for the revision of the 2020 Korean dietary reference intakes for folate, and suggestions for future revisions. Based on the changes in the standard body weight in 2020, the adequate intake (AI) for infants (5-11 months) and the estimated average requirements (EARs) for 15-18 years of age were revised, but there were no changes in the recommended nutrient intakes (RNIs) and tolerable upper intake levels (ULs) for all age groups. Mean folate intake did not reach RNI in most age groups and was particularly low in women aged 15-29 years, according to the results of the 2016-2018 Korea National Health and Nutrition Examination Survey (KNHANES). The percentages of folate intake to RNI were lower than 60% in pregnant and lactating women, but serum folate concentrations were higher than those in other age groups, presumably due to the use of supplements. Therefore, total folate intake, from both food and supplements, should be evaluated. In addition, the database of folate in raw, cooked, and fortified foods should be further expanded to accurately assess the folate intake of Koreans. Determination of the concentrations of erythrocyte folate and plasma homocysteine as well as serum folate is recommended, and quality control of the analysis is critical.

• Journal of the Korean Society of Food Culture
• /
• v.39 no.1
• /
• pp.53-63
• /
• 2024

This study aimed to investigate the relationship between the nutrition quotient and the dietary intake of adolescents. A total of 393 adolescents were surveyed to evaluate their Nutrition Quotient for Korean Adolescents (NQ-A) scores and dietary intake. The average age of the survey subjects was 15 years and the average NQ-A score of the subjects was 49.11±13.35. There was no significant difference in the NQ-A scores according to gender and age. The average dietary diversity score was 3.77±0.85, and it was significantly higher in boys than in girls (p< .05) with the scores of 12-14-year-old students being significantly higher than those aged 15-18 years (p< .01). The results of comparing the percentage of recommended intake or adequate intake and the mean adequacy ratio (MAR) according to the NQ-A grade, showed that the 'High' grade had a significantly higher intake percentage of vitamin B1, B12, folate, phosphorus, iron and a significantly higher MAR (p< .05). From a long-term perspective, efforts to improve dietary habits are deemed necessary to meet an individual's nutritional requirements. Adolescents themselves should develop proper eating behaviors and acquire suitable dietary management skills to enhance their nutritional status, ultimately contributing to an improvement in their quality of life.

• Journal of Nutrition and Health
• /
• v.52 no.2
• /
• pp.217-226
• /
• 2019

Purpose: This study examined the nutrient intake and dietary habits based on breakfast consumption in Korean adolescents. Methods: The data of the 2013 ~ 2015 Korea National Health and Nutrition Examination Survey (KNHANES) were used in this study. The analysis included 1,281 adolescents aged 12 to 18 years. The subjects were divided into two groups (EBF: eating breakfast, n = 911; SBF: skipping breakfast, n = 370). Results: The EBF group was significantly younger than the SBF group. In addition, the EBF group had a significantly lower frequency of skipping dinner than the SBF group. The EBF group consumed significantly higher levels of most nutrients except for vitamin A than the SBF group. The percent of nutrient intake under the EAR (estimated average requirements) in the EBF group were also significantly lower than that in the SBF group. Moreover, the NAR (nutrient adequacy ratio) and MAR (mean adequacy ratio) of the EBF group were significantly higher than those of the SBP group. The intake of cereal, sugars and sweeteners, vegetables, and eggs in the EBF group was significantly higher than that in the SBF group. Conclusion: The habit of skipping breakfast in adolescents leads to a decrease in the total nutrient intake and imbalanced dietary habits. Breakfast consumption in adolescence is very important. Therefore, more studies will be needed to develop nutrition education systematically in Korean adolescents.

• Journal of Nutrition and Health
• /
• v.55 no.3
• /
• pp.321-329
• /
• 2022

Riboflavin and its derivatives, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), are key components of mitochondrial energy metabolism and oxidation-reduction reactions. Proposed dietary reference intakes for Koreans (KDRIs), that is, estimated average requirements (EARs), for riboflavin, based on current knowledge of riboflavin and riboflavin derivative levels, and glutathione reductase activity, are 1.3 mg/d for men aged 19-64 years and 1.0 mg/d for women aged 19-64 years. By applying a coefficient of variance of 10%, reference nutrient intakes (RNIs) were set at 1.5 mg/d for men aged 19-64 years and 1.2 mg/d for women aged 19-64 years. Likewise, EARs and RNIs of riboflavin intake were proposed for all age groups and women in specific life stages such as pregnancy. Mean adult riboflavin intake for adults aged ≥ 19 years was 1.69 mg/d in Korea National Health and Nutrition Examination Survey (KNHANES) 2020, which was 124.9% of EAR according to the 2020 KDRIs. In the 2015-2017 KNHANES study, the mean riboflavin intake from foods and supplements was 2.79 mg/d for all age groups, and 32.7% of individuals consumed less riboflavin than EAR according to the 2020 KDRIs. For those that used supplements, mean intakes were 1.50 mg/d for riboflavin from foods, 10.26 mg/d from supplements, and 11.76 mg/d from food and supplements, and 5.5% of individuals consumed less riboflavin than EAR. Although the upper limit of riboflavin has not been established, the merits of increasing supplement use warrant further consideration. Also, additional epidemiologic and intervention studies are required to explore the role of riboflavin in the etiology of chronic diseases.

• Journal of Nutrition and Health
• /
• v.42 no.1
• /
• pp.23-37
• /
• 2009

The purpose of this study was to investigate the health status of preschool children using the questionnaires about dietary behaviors and anthropometric indices. And also nutritional status was investigated using questionnaires for 24-hr recall method. The study was conducted in 145 children aged 3 to 6 years and questionnaires for dietary behaviors and dietary intakes were performed by mothers of children in Ulsan. Just nine percent of children were graded as good in terms of having healthy eating habits, this means that the nutrition education for the dietary behaviors should be more focused on preschool children. With regard to the frequency of food intake, children consumed green & yellow vegetables less frequently, meanwhile consumed high protein source food (meat, egg and bean) and milk and its product more frequently. Children almost never consumed fried foods as often as 1-2 times a weak. In assessment of the health status, children have the highest prevalence of colds and allergy, but lower prevalence of clinical symptoms due to the nutritional deficiency. The mean height was $103.6\;{\pm}\;6.4\;cm$ and significantly different among age (p < 0.05), but was not significantly different between sex. The mean weight was $17.8\;{\pm}\;3.0\;kg$ and significantly different in 5, 6years old among age. By the WLI criteria, 11.1% of children were underweight and 17.4% of children were overweight or obese. By the Rohrer index criteria, any children were not underweight and 86.8% of children were overweight or obese. By the Kaup index criteria, 2.8% of children were underweight and 29.2% of children were overweight or obese. And Obesity Index criteria, 2.1% of children were underweight and 20.8% of children were overweight or obese. The results of obesity rate by all criteria except Rohrer index indicated similar level, were significantly high in age 3 with all criteria, and decreased with age increased. The energy intake of children was lower than EER (Estimated Energy Requirements) of Dietary Reference Intakes for Koreans (KDRIs) by as much as 85.7%. Acceptable Macronutrient Distribution Ranges (AMDR) was 62.6:21.5:15.7 as carbohydrate:protein:lipid, so children consumed protein more, but consumed lipid less compared with those of KDRIs. Vitamin A intake was 133% of recommended intakes (RI) and calcium intake which was identified as the nutrient most likely to be lacking in diets was 98.9% of RI. The intakes of all minerals and vitamins except folate were higher than KDRIs. 33.3% of children were distributed in insufficiency of energy intake, 42.7% of children were distributed in insufficiency of lipid intake. These results indicate that the need of developing of nutrition education program and further concern of a public health center, university and children care center about dietary life for preschool children.