• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.6-10
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• 2003

The optimum organic acid and temperature conditions were investigated for the preparation of oligosaccharides from agar. The tested organic acids were acetate, citrate, lactate, malate, and succinate and the conditions for oligosaccharides preparation were $0.3\%,\;0.5%;and\;0.7\%$ organic acid concentrations at $80\~120^{\circ}C.$ The low concentration of organic acid below $0.3\%$ decreased the degrading ratio and the high concentration up $0.5\%$ could not changed the degrading ratio. Conditions below $100^{\circ}C$ was not good for degrading agar. But $100^{\circ}C\;or\;120^{\circ}C$ was optimal temperature conditions for agarooligosaccharides according to the organic acid type and concentration. The organic acid concentration was $0.5\%$ and organic acid was the citrate or malate. The treatment time considered optimum was 120$\~$180 min. The maximal degrading ratio giving optimum conditions such as $100^{\circ}C\;and\;120^{\circ}C\;was\;35.5\%\;and\;38.7\%,$ respectively. The agarooligosaccharides prepared by autoclaving at $100^{\circ}C\;and\;120^{\circ}C$ were 2$\~$7 species oligomer.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.21-30
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• 1988

To study the optimum fermentation and aging conditions for preparation of Andong Sikhe which is consumed in the northern Kyungbuk province as a traditional beverage, Sikhe were fermented and aged at $12^{\circ}C$ for 48, 60 and 72hrs and fermented at 40, 50. and $60^{\circ}C$ for 2, 3, and 4hrs and then aged at $12^{\circ}C$ for 20 hrs, Non-volatile organic acids and free sugars were analyzed by GC and HPLC, respectively, and sensory test was performed. Sikhe fermented at $40^{\circ}C$ for 3hrs and aged at $12^{\circ}C$ for 20hrs was evaluated the most favorable one by sensory test. This Sikhe had the lowest pH 4.6~4.7 among sample and 14.6% of sugar. The sugar content was lower than those of Sikhe Fermented at $50^{\circ}C$ and $60^{\circ}C$. In organic acid analysis, the concentration of malate 67.53%/mg in this Sikhe was the highest. Lactate, succinate and maleate were produced more in this Sikhe than in any other ones. Oxalate which was existed before fermentation was not found in the Sikhe, and a small amounts of citrate and fumarate were produced. In sugar analysis, maltose was dominant 11.56%, glucose 1.25% and fructose 0.45%.

• Journal of Life Science
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• v.31 no.8
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• pp.778-785
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• 2021

The germination of cucumber seeds begins with the degradation of reserved oil to fatty acids within the lipid body, which are then further metabolized to acyl-CoA. The acyl-CoA moves from the lipid body to the glyoxysome following β-oxidation for the production of acetyl-CoA. As an initial carbon source supplier, acetyl-CoA is an essential molecule in the glyoxylate cycle within the glyoxysome, which produces the metabolic intermediates of citrate and malate, among others. The glyoxylate cycle is a necessary metabolic pathway for oil seed plant germination because it produces the metabolic intermediates for the tricarboxylic acid (TCA) cycle and for gluconeogenesis, such as the oxaloacetate, which moves to the cytosol for the initiation of gluconeogenesis by phophoenolpyruvate carboxykinase (PEPCK). Following reserved oil mobilization, the production and transport of various metabolic intermediates are involved in the coordinated operation and activation of multiple metabolic pathways to supply directly usable carbohydrate in the form of glucose. Furthermore, corresponding gene expression regulation compatibly transforms the microbody to glyoxysome, which contains the organelle-specific malate synthase (MS) and isocitrate lyase (ICL) enzymes during oil seed germination. Together with glyoxylate cycle, carnitine, which mediates the supplementary route of the acetyl-CoA transport mechanism via the mitochondrial BOU (A BOUT DE SOUFFLE) system, possibly plays a secondary role in lipid metabolism for enhanced plant development.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1741-1744
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• 2011

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.136-138
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• 2002

In this work we describe the on-line monitoring technique for the analysis of fumaric acid in biotechnological processes. Fumarase and malate dehydrogenase(MDH) were immobilized on epoxy carrier and integrated into a FIA system. The effects of carrier buffer flow rate, pH, reaction temperature on the immobilized fumarase/MDH were investigated for the development of a fumarate-FIA system. Furthermore the effects of substrates, salts and metabolites dissolved in the sample on the activity of the immobilized enzyme were investigated.

• Korean Journal of Microbiology
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• v.13 no.1
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• pp.24-30
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• 1975

this work was designed to study the species belonging to Family Rhodospirillaceae in Korea. The species of Rhodopseudomonas palustris and R. gelatinosa were isolated and identified. The utilization of various substrates such as malate, succinate, citrate, pyruvate, propionate and acetate were tested with isolated KS 007 and KS o16. Though there were some differences according to nitrogen source in media it was thought that he intermediates of TCA cycle were comparatively good substrates, Also it was confirmed that isolated strains have the ability of nitrogen fixation.

• The Korean Journal of Zoology
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• v.17 no.4
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• pp.163-166
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• 1974

Malate dehydrogenases of ten bivalved mollusks consist of one or two isozyme, which are species-spcific. It is concluded that the electrophoretic character of the enzyme is available for identification of these ten bivalves.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.62-67
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• 1995

Deliveries of tar, nicotine and carbon monoxide in mainstream smoke decreased with increment of exogenous potassium content of tobacco. Potassium malate was more effective than potassium nitrate, potassium carbonate, potassium citrate and potassium oxalate for the reduction of carbon monoxide, but potassium nitrate was more effective than potassium palate, potassium carbonat, potassium citrate and potassium oxalate for the reduction of carbon in the case of nicotine. Puff count and burning rate were slightly changed with added potassium salts.

• Journal of Plant Biology
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• v.20 no.1
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• pp.1-5
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• 1977

Horizontal starch gel electrophoresis in three buffers was used to compare the electrophoretic patterns in three cherry species, wild Prunus subhirtella, cultivated P. yedoensis and P. donarium. Electrophoretic patterns of glutamate oxaloacetate, transaminase-2(GOT-2), malate dehydrogenase-2(MDH-2), and phosphoglucose isomerase(PGI) in three species showed strong evidence that P. yedoensis might be originated by hybridization between P. subhirtella and P. donarium.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.55-63
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• 1985

Phosphate, ammonia, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate were examined for their ability to control the heat-stable enterotoxin (ST) production in succinate salts medium or in M9 medium. The results obtained were summerized as follows. 1. When the initial phosphate concentration was adjusted to 1.0mM, ST production was decreased to 80u/ml or less. But when the initial phosphate concentration was adjusted to 64mM or 100mM, enterotoxin production was 320u/ml. 2. When the initial ammonia concentration in the medium was adjusted to 1.0mM, no ST production and cell growth were observed. But when ammonia concentration was adjusted to 10mM, 19mM, 38mM or 76mM, enterotoxin production was 320u/ml. 3. Among carbon sources, glucosamine, glucose, pyruvate, succinate, fumarate, malate and acetate, acetate supported the highest specific production (928 unit/O.D.) of heat-stable enterotoxin. From this results, we could assume that heat-stable enterotoxin production is controlled by stringent control mechanism. 4. When the pH of the succinate salts medium was kept between 6.2 to 6.5, no heat-stable enterotoxin production was observed, but when the pH of the medium was kept between pH 6.2 to 6.5, 267 unit/O.D. of heat-stable enterotoxin was produced. 5. Glucose inhibited the heat-stable enterotoxin production and the mechanism was assumed due to its capacity to lower the pH of the medium during catabolysis and its high metabolic energy.