• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.271-276
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• 1997

An ascorbic acid phosphorylating enzyme, which catalyzes the formation of ascorbic acid-2-phosphate from ascorbic acid and pyrophosphate, was purified 32.7-folds to homogeneity from a cell-free extract of Cellulomonas sp. AP-7. The combination of DEAE- Sephacel ion exchange chromatography and Sephacryl S-200 get filtration was used for their purification. The molecular weight of the native protein was estimated to be 96.lkDa on high performance gel filtration chromatography. The SDS-PAGE analysis indicated that the protein consisted of four identical subunits of 24.6 kDa. The purified enzyme showed the optimal tempeature of 40$\circ$C and optimal pH of 4.5. The Km for ascorbic acid and pyrophosphate were 119 mM and 11.9 mM, respectively. The addition of 5,5'-dithiobis-(2-nitrobenzoic acid) into the reaction mixture resulted in the reduction of the enzyme activity at 51%. The enzyme also had a phosphatase activity at weakly acidic pH and the Km for ascorbic acid-2-phosphate in phosphatase activity was 7.9 mM.

• Journal of Pharmaceutical Investigation
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• v.21 no.2
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• pp.97-101
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• 1991

Six different O/W cream bases containing 4% ascorbic acid dipalmitate and two different O/W cream bases containing 1% ascorbic acid were prepared. Percutanceous absorption of ascorbic acid as well as safety were determined using rabbits. The stability of the creams was also tested at room temperature. Ascorbic acid concentrations in urines varied depending on the characteristics of cream bases used. The absorption of ascorbic acid was increased and sustained with the cream bases containing branched chain esters of fatty acid instead of natural oils used currently. The excretion level of ascorbic acid in urine was high with the cream base including nonionic surfactants and a small quantity of natural oils. The creams containing nonionic surfactants showed excellent stability, while those containing anionic surfactants were not stable in terms of pH, odor and coloring test at room temperature during six months. But, the two creams containing ascorbic acid were unstable. All the cream bases tested showed good safety.

• Journal of the Korean Home Economics Association
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• v.32 no.1
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• pp.181-188
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• 1994

The purpose of this study is to evaluate nutritional status of ascorbic acid in 96 Korean female college students. Dietary intake level was estimated with three day diet records. Serum ascorbic acid were analyzed with fasting blood. Nutrient intakes was calculated using three different food composition databases ; analysis data of cooked food items ; analysis data of raw foods ; published food composition table. Ascorbic acid intake levels calculated with different food composition databases differed by 15% Using analysis data of cooked foods resulted in the lowest intake level 49.26 mg per day. Main sources of ascorbic acid investigated were Cheju mandarin orange juice and hard persimmon orange juice and Kimchi. Mean value of serum ascorbic acid level was 1.04 mg/dl and 4.2% of subjects were in marginal risk or deficient range. It was found to significantly correlate asscorbic acid intake with serum ascorbic acid content. Correlation coefficient with results calculated using analyzed data was higher than that using published data. Serum levels and mean daily intake levels of ascorbic acid in the subjects were significantly correlated. From these results it is concluded that ascorbic acid content of cooked foods should be included in the Food Composition Tables in Korea. Korean female college students were in lower risk of ascorbic acid deficiency.

• Journal of Oriental Neuropsychiatry
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• v.6 no.1
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• pp.41-49
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• 1995

This study aimed to compare the anti-stress effect of Guibitang with Ascorbic Acid on the guinea pigs in heat or forced swimming stress. the experimental animals were heated in hot room$(34{\pm}2^{\circ}C)$ for 2 hours in a day during 7 days. Forced swimming stress was loaded by forcing guinea pigs to swim in a oval tub for 2 minutes in a day during 7days. And administered 1.0mg/100g of Ascorbic Acid or 86.0mg/100g of Guibitang extract formonce befor stress. 1. In brain, the contents of norepinephrine in group of the heat of forced swimming stress, in case administered Ascorbic Acid and in case administered Guibitang extract with Ascorbic Acid significantly decreases as compared with these in case administered non Ascoric Acid. 2. In brain, the contents of epinephrine in group of the forced swimming stress, in case administered Guibitang extract with Ascorbic Acid significantly decreases as compared with these in case administered non Ascorbic Acid. 3. In brain, the contents of dopamine in group of the heating stress, in case administered Guibitang extract with Ascorbic Acid significantly decreases as compared with these in case administered non Ascorbic Acid, and these in group of the forced swimming stress in case administered Ascorbic Acid and in case administered Guibitang extract without Ascorbic Acid and in case administered Guibitang extract with Ascorbic Acid significantly decreases as compared with these in case administered non Ascorbic Acid.

• Journal of the Korean Home Economics Association
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• v.31 no.4
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• pp.201-208
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• 1993

The ascorbic acid contents of 101 food items were analyzed by HPLC to provide database to estimate dietary intakes of ascorbic acid of Korean. Foods with high contents of ascorbic acid were green vegetables, citrus fruits, strawberry, kiwi, and fruit juices. This analysis data of ascorbic acid contents in some food items showed significant deviations compared with other Food Composition Table. Ascorbic acid content in soups were lower than those of raw foods by about 57%. The ascorbic acid contents in blanched or seasoned after blanching vegetables and boiled or steamed meals turned out to be decreased by about 52.3% and 47.5%, respectively, but the degrees were varied with the kind of foods as well as cooking methods. The ascorbic acid intakes from 18 most frequently consumed meals in Korea were determined to be about 1/2 of Food Composition Table according to this analysis data. The results showed the importance of accurate food database in assessing nutrient intake levels of population.

• Biomedical Science Letters
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• v.28 no.2
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• pp.101-108
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• 2022

High-fat diet (HFD)-fed ovariectomized (OVX) female mice were used as an animal model of obese postmenopausal women. We investigated the effects of ascorbic acid on the histological changes induced in the liver. Plasma alanine aminotransferase levels and liver weights were higher in mice fed an HFD for 18 weeks than in mice fed a low-fat diet, effects that were inhibited by ascorbic acid. Similarly, mice fed an ascorbic acid-supplemented HFD had less hepatic lipid accumulation than did mice fed an HFD alone. Moreover, administration of ascorbic acid reduced inflammatory cells, including mast cells and CD68-positive cells, and inflammatory foci in the liver and inhibited hepatocyte ballooning. Hepatic collagen levels were lower in ascorbic acid-treated versus non-treated mice. These results suggest that ascorbic acid inhibits hepatic steatosis, inflammation, and fibrosis in obese OVX mice. Thus, ascorbic acid intake may be useful for postmenopausal women with nonalcoholic fatty liver disease.

• The Korean Journal of Physiology
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• v.12 no.1_2
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• pp.15-23
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• 1978

The action of ascorbic acid on the sodium Plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action if ascorbic acid on the ATPase activity The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by ascorbic acid and the concentration of ascorbic acid for maximal activity is about 8 mM. 2. The activating effect of ascorbic acid on the ATPase activaty, with a given concentration of sodium in the medium, is increased by raisins the potassium concentration but activity ratio is decreased. 3. The activating effect of ascorbic acid on the ATPase activity, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 4. The action of ascorbic acid on the ATPase activity is stimulated by calcium ions and activity ratio is increased by raising the calcium concentration. 5. The activating effect of ascorbic acid on the ATPase activity was not related to the sulfhydryl group of cysteine or the hydroxyl group of threonine. 6. The activating effect of ascorbic acid on the ATPase activity is due to amino group and carboxyl group of the enzyme of NaK ATPase.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.457-461
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• 2005

During the last few years, considerable progresses have been made in understanding of roles and biosynthesis of ascorbic acid (AsA) in plants. The concentrations of ascorbic acid is 2-4 mM in leaf cells, but much higher at the chloroplast. There are three forms of ascorbic acid in the plant mainly ascorbic acid (AsA), monode­hydroascorbic acid (MDHA) and dehydroascorbic acid (DHA). AsA in plant cell performs antioxidants by changing those three forms. And AsA promotes cell division and elongation There was new pathway of ascorbic acid metabolism. It is called pathway of Smirnoff-Wheeler. This report will provide understanding of AsA in plants, and also provide

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.293-297
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• 2003

Glutathione and ascorbic acid have been shown to fulfill many essential functions in animal and plant growth, development, defence and protection against oxidative damage. Effects of glutathione and ascorbic acid were examined in transgenic N. tabacum cells producing hGM-CSF to determine the effects of the vitamins on growth and cell viability. In lag phase, cell viability was preserved by glutathione and ascorbic acid. Therefore, recombinant protein productivity was increased. The purpose of present study is to investigate the role of antioxidants in cold stress-induced apoptosis in plant suspension cells. Cold stress lowered cell viability and increased total genomic DNA fragmentation. Supplementing the cell cultures with glutathione and ascorbic acid inhibited cold stress-induced decrease in cell viability and increase in total genomic DNA fragmentation.

• The Journal of the Korean dental association
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• v.55 no.9
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• pp.592-603
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• 2017

Purpose: The effects of various concentrations of ascorbic acid on stem cell spheroids derived from intraoral areas are not known yet. Thus, the purpose of this study is to evaluate the effects of different concentrations of ascorbic acid on the morphology and cellular viability of stem cell spheroids derived from the gingival tissues. Materials and Methods: Stem cells were plated onto silicon elastomer-based concave microwells and grown in the presence of ascorbic acid at concentrations ranging from 0.003% to 0.3%. The morphology of the cells was viewed under an inverted microscope at day 1, 2, 3 and 5. Qualitative live/dead assay and quantitative cellular viability using Cell Counting Kit-8 were performed on day 2 and day 5. Results: Gingiva-derived stem cells formed spheroids irrespective of ascorbic acid concentration in silicon elastomer-based concave microwells. Increase in the diameter of spheroid were seen with higher concentrations of ascorbic acid. Higher cellular viability was seen in higher concentrations of ascorbic acid. Conclusion: Within the experimental setting, the application of ascorbic acid on stem-cell spheroids produced an increase in the size and higher viability with higher dosage. It can be suggested ascorbic acid be applied with stem cell spheroids for tissue engineering purposes.