• Korean journal of food and cookery science
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• v.18 no.2
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• pp.173-178
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• 2002

Fresh Shiitake mushrooms were irradiated by UV-B or dried by using hot air to increase the vitamin D$_2$content. Vitamin D$_2$content was determined by high-performance liquid chromatography Irradiating the inside of the mushroom cap was more effective in increasing vitamin D$_2$content than irradiating the outside of the mushroom cap. Irradiation of UV-B at 0, 2.5, 5.0, 7.5 and 10 J/㎠ increased the content of vitamin D$_2$in the mushroom to 21.51, 120.78, 144.38, 168.08, and 187.69 $\mu\textrm{g}$/g, respectively. Vitamin D$_2$content of Shiitake mushrooms with irradiation of 10 J/㎠ decreased from 187.69 to 98.78 $\mu\textrm{g}$/g by 6 hours of hot-air drying. When three kinds of drying method (UV-B irradiation followed by hot-air drying, hot-air drying, and sunlight drying) were compared, the combination of UV-B irradiation and hot-air drying was the most effective in terms of increasine the vitamin D$_2$content in the mushroom.

• Journal of Nutrition and Health
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• v.35 no.3
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• pp.322-331
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• 2002

This study was carried out to evaluate the effect of vitamin $B_{6}$ intake by normal term delivery pregnant women on the concentration of vitamin $B_{6}$ in the material plasma, the umbilical cord plasma, and the placental tissue. Dietary intake data were obtained from a semi-quantitative frequency questionnaire. The daily mean energy and protein intakes were 2189.5 kcal (93.2% of RDA) and 79.3 g (113.3% of RDA), respectively. The average daily vitamin $B_{6}$ intake was 1.7 mg (91.4% of RDA) for the pregnant women. Their main sources of vitamin $B_{6}$ were cereal & starch (50%), and vegetables & fruits (33%). The pyridoxal phosphate (PLP) concentration of the maternal plasma, the umbilical cord plasma, and the placenta were 16.7 $\pm$ 4.1 nmol/1, 61.3 $\pm$ 19.8 nmol/l and 898.6 $\pm$ 159.2 ng/g, respectively. The PLP level was the highest in the placenta. The PLP level of the maternal plasma was significantly lower than the of the umbilical cord plasma (p < 0.001). The PLP level of maternal plasma correlated positively with that of the placenta (p < 0.0001) and the umbilical cord plasma (p < 0.05). Also the PLP level of the placenta correlated positively with that of the umbilical cord plasma (p < 0.05). These findings indicate that the vitamin $B_{6}$ nutritional status of the fetus is affected by placental vitamin $B_{6}$ levels, and that the placental vitamin B$_{6}$ levels reflect the maternal vitamin $B_{6}$ status. The umbilical cord plasma PLP level showed a positive correlation with the gestational length (p < 0.05). A negative association was observed between the PLP level showed of the umbilical cord plasma and the pregnancy weight gain (p < 0.03). The results suggest that the transfer of PLP from maternal plasma to the placental tissue could be an active transport, white the transfer of PLP from the placenta to the fetus is by means of simple diffusion. Thus, neonatal vitamin $B_{6}$ nutrition is influenced by the maternal nutritional status.

• Journal of the Korean Dietetic Association
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• v.10 no.4
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• pp.417-427
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• 2004

The purpose of this study was to investigate children's nutrient intakes by school lunch. Evaluation of nutrient intakes by school lunch for three days was conducted with 86 children in urban and 64 children in rural of Jeonbuk area. The results of this study were as follows. 1) With respect to amounts of provided nutrients in school lunch, CPF (carbohydrate : protein : fat) energy ratio was 48.6 : 19.7 : 31.6 in urban and was 46.7 : 20.5 : 32.7 in rural. Compared to 1/3 RDA (RDA) of children for 10-12 years, folic acid and zinc were provided below 50 % of RDA. Protein, fat, phosphorus, vitamin $B_1$, vitamin $B_2$, niacin, vitamin C and vitamin E were provided above 125 % of RDA. There were no differences in amounts of provided nutrients-except calcium, vitamin A, vitamin $B_6$, folic acid and zinc-between urban and rural. 2) With respect to amounts of nutrient intakes, CPF energy ratio was 51.1 : 17.4 : 31.5 in urban and 47.5 : 19.7 : 32.7 in rural. Compared to RDA, folic and zinc were below 50 % of RDA. Iron and vitamin $B_6$ were below 75 % of RDA. Protein, fat, phosphorus and vitamin E were above 125 % of RDA. There were significant differences in nutrient intakes between urban and rural. The children in rural showed higher levels of nutrient intakes-energy, carbohydrate, protein, fat, calcium, phosphorus, iron, zinc, vitamins and folic acid-compared to those of children in urban. These results suggest that programs are needed for providing adequate nutrient intakes for children in school lunch and for improving nutrient intakes of children in urban.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.52-55
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• 2000

The effects of environmental conditions, initial dissolved oxygen concentrations, pH, and the presence of electron carrier vitamin B$_{12}$ , on the reduction rate of TNT by Fe$^{0}$ was Quantitatively analyzed using a batch reactor. In all experiments, TNT reduction was best described with a first order reaction and the reduction rate decreased with the increase in the initial DO concentration. However, the specific reaction rate did not decrease linearly with the increase in the initial DO concentration. In the presence of HEPES buffer 0.2 and 2.0 mM(pH 5.7$\pm$0.2), the specific reaction rate increased more than 5.8 times, which showed reduction rate is rather significantly influenced by the pH of the solution. To test the possibility of reaction rate enhancement, well-known electron carrier(or mediator), vitamin B$_{12}$ has augmented besides Fe$^{0}$ . In the presence of 8.0 $\mu\textrm{g}$/L of vitamin B$_{12}$ , the specific reaction rate increased as much as 14.6 times. The results indicate that the addition of trace amount of vitamin B$_{12}$ can be a promising rate controlling option for the removal of organics using a Fe$^{0}$ filled permeable reactive barrier.

• Korean Journal of Human Ecology
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• v.10 no.4
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• pp.411-419
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• 2001

This study was peformed to assess the nutritional status of female nursing home residents by dietary intake. The subjects were 60 nursing home residents aged over 60 from 3 different nursing homes in Seoul, Cheonan and Chunchon. Dietary intake was assessed by 24-hr recall and nutrient intake was calculated using CAN-Pro and database for vitamin E established by authors. To establish vitamin E database, we analyzed vitamin E concentration using HPLC in several foods consumed frequently by nursing home residents. The results of nutrient intake were as follows; 1) Average daily intakes of energy, protein, phosphorous, iron, vitamin $B_1$ and niacin were higher than RDA, but calcium, vitamin $B_2$ and niacin of Chunchon were lower than RDA. 2) Intakes of protein, sodium and niacin of Cheonan residents were significantly higher than those of Seoul. 3) Intakes of phosphorous, potassium, vitamin $B_1$ and dietary fiber of Cheonan residents were significantly higher than Seoul and Chunchon. 4) Intakes of sodium and cholesterol of Seoul residents were higher than Cheonan and Chunchon. 5) Average daily intake of vitamin E was lower than RDA. Especially vitamin A intake of Cheonan residents was significantly lower than other two cities.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.335-342
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• 2021

Vitamin B12 deficiency may lead to serious health issues in both infants and adults. A simple analytical method involving sample pretreatment with enzyme, followed by cyanide addition under acidic conditions; separation on an immunoaffinity column; and high-performance liquid chromatography (HPLC) was developed for the rapid detection and quantitation of vitamin B12 in powdered milk. Detection limit and powdered milk recovery were determined by quantitative analysis. The limits of detection and quantitation were 2.71 and 8.21 ㎍/L, respectively. Relative standard deviations of the intra-day and inter-day precisions varied in the ranges of 0.98%-5.31% and 2.16%-3.90%, respectively. Recovery of the analysis varied in the range of 83.41%-106.57%, suggesting that the values were acceptable. Additionally, vitamin B12 content and recovery in SRM 1849a were 54.10 ㎍/kg and 112.24%, respectively. Our results suggested that the analytical method, including the sample pretreatment step, was valid. This analytical method can be implemented in many laboratory-scale experiments that seek to save time and labor. Therefore, this study shows that immunoaffinity-HPLC/ultraviolet is an acceptable technique for constructing a reliable database on vitamin B12 in powdered milk containing starch as well as protein and/or fat in high amounts.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.611-617
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• 1990

This study was conducted to breed a high vitamin $B_{12}$ producer by the fusion of protoplasts between Bacillus natto and Bacillus megaterium. Auxotrophic mutants of Bacillus natto SH-34 ($thr^-try^-rif^r$) and Bacillus megaterium BK-13 ($arg^-ade^-lys^-str^r$) which showed high protease activity and production of vitamin $B_{12}$, respectively, were isolated for the fusion experiment. Protoplasts were induced by incubating the cells with lysis solution containing $500{\mu}/ml$ lysozyme, and the ratio of protoplast and regeneration formation were ranged from 99% and 67%, respectively. Fusion frequencies of fusants between Bacillus natto SH-34 and Bacillus megaterium BK-13 were appeared in the ranges of $1.0{\times}10^{-5}$ under the treatment of 30% PEG 6000 containing 3% PVP. The fusant, MNF-72 showed the highest product yield of $7.85{\mu}g/g-cell\;vitamin\;B_{12}$ in production medium. For the improvement of productivity, the immobilization of fusants with sodium alginate was carried out. In batch and continuous fermentation systems, the productivity were determined to be $0.58{\mu}g/ml.hr\;and\;0.80{\mu}g/ml.hr\;vitamin\;B_{12}$ under optimum condition, respectivity.

• Journal of the Korean Society of Food Culture
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• v.35 no.5
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• pp.493-502
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• 2020

The objective of this study was to investigate the effects of dietary vitamin B intake on biomarkers related to lipid metabolism, inflammation and blood glucose control, that are important in the development of type 2 diabetes and its complications. Seventy-six adults (42 males, 34 females) were recruited from a group of diabetes patients who had visited the medical center for treatment. Data on anthropometric characteristics and dietary intake of thiamine, riboflavin, niacin, vitamin B₆ and folate were collected using 24-hour diet recall and the CAN Pro 4.0 program. Also, data on clinical indices such as serum lipids, blood pressure, high-sensitivity C-reactive protein (hs-CRP), hemoglobin A1c (HbA1c) and homeostasis model assessment 2-insulin resistance (HOMA2-IR) were collected and analyzed for correlation with dietary vitamin B intake. Results from the dietary intake survey showed that riboflavin and folate intake (in males) and folate intake (in females) were below the Dietary Reference Intake for Koreans. Statistical analysis revealed a negative correlation between hs-CRP and dietary intake of B vitamins. Riboflavin intake was inversely associated with systolic blood pressure after adjustments for age, BMI, smoking, alcohol consumption, exercise, ingestion of diabetes mellitus medication and energy intake (p<0.05). Our results suggest that dietary vitamin B may influence inflammation and consequently may help in better management of type 2 diabetes.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.112-115
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• 1987

Optimal pH temperature and sucrose content for the production of vitamin B$_{12}$ and riboflavin by Bacillus megaterium and Enterobacter aerogenes was studied by microbiological analysis. Optimal pH for the production of B$_{12}$ was 6.0 by B. megaterium while the pH for E. aerogenes was 5.0. However, upon the addition of sucrose the optimal pH for B. megaterium shifted to 7.5 but E. aerogenes remained at pH 5.0. In the absence of sucrose, pH did not influence the yields of riboflavin produced by either bacterium. Addition of sucrose stimulated synthesis of riboflavin by both bacteria. Temperature had little effect on the production of vitamins by either bacterium.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.191-194
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• 2013

The fresh fruit bodies of Pleurotus eryngii var. ferulae was irradiated with ultraviolet (UV)-B (280-320 nm) in order to increase vitamin $D_2$ contents, which was assayed using HPLC (Waters 1525, USA). The vitamin $D_2$ contents were $3.5{\mu}g/g$ after 3 min UV-B irradiation ($21.6KJ/m^2$) and $6.02{\mu}g/g$ after 5 min UV-B irradiation ($36KJ/m^2$), respectively, which showed the significant increase considering the vitamin $D_2$ content ($0.01{\mu}g/g$) before UV-B irradiation. This increasing effect was confirmed also for other edible mushrooms; Pleurotus eryngii, from $0.09{\mu}g/g$ to $2.75{\mu}g/g$ (3 min) and $5.21{\mu}g/g$ (5 min); Lentinus edodes, from $0.021{\mu}g/g$ to $3.02{\mu}g/g$ (3 min) and $3.78{\mu}g/g$ (5 min); Pleurotus ostreatus, from $0.19{\mu}g/g$ to $9.63{\mu}g/g$ (3 min) and $11.6{\mu}g/g$ (5 min). Although the original content of vitamin $D_2$ was the highest in P. ostreatus, the extent of increase by UV irradiation was remarkably high in P. eryngii var. ferulae.