• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.211-217
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• 2000

To standardize quality characteristics of commercial doenjang prepared by traditional method, general components, organic acids, amino acids and fatty acid composition were investigated. Moisture, crude protein, crude lipid, titratable acidity (expressed as milliliter of 0.1 N NaOH), acid value and salinity were 54.7%, 13.8%, 8.0%, 14.4mL, 45.7mg/g and 11.8%, respectively. The content of amino type nitrogen was 345.3mg% (w/w) in the range of 207.6 to 443.5mg% being 1.1~2.2-fold for all samples. Average value of Hunter color for L(lightness), a(redness) and b(yellowness) were 37.4, ＋9.7 and ＋21.3, respectively. Browning index value(expressed as optical density at 425 nm) of water-soluble compound(2.58) was above 7.1 times higher than that of the water-insoluble compound(0.38). Total contents of free and total amino acid were 3.81 and 9.72%, respectively, and then the former(1.1~3.7 times) was more different in all samples tested than that of the latter(1.1~2.0 times). Among amino acids, glutamic acid was abundant and its content of free and total amino acids was 0.57 and 1.24%, respectively. Of organic acids, lactic acid was the most abundant being 0.34%(average) and ranged from 0.15 to 0.86%. Linoleic acid(52.17%, as area%) was the highest content of the total fatty acids. Unsaturated and polyunsaturated fatty acids were 83.89 and 61.189%, respectively. Polyunsaturated fatty acid was markedly different among all samples and ranged from 51.52 to 64.91%.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.399-403
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• 1999

Effects of heating, pH, organic acids and some salts on color changes of ground garlic, expressed by Hunter color values, were investigated during storage. The organic acids, such as acetic, citric and lactic acids rather enhanced greening, while NaCl affected little. As the pH decreased to 4.0, greening was significantly reduced. Among the several phosphates tested, $Na_{2}HPO_{4}\;and\;Na_{3}PO_{4}$ showed some positive effects and other chemicals, such as BHA, BHT, propyl gallate and glutathione showed little or negative effects on both greening and browning of ground garlic. Heating at $80^{\circ}C$ for up to 10 mins at pH range of $3.0{\sim}5.0$ caused a severe greening mostly, while heating at $90\;and\;100^{\circ}C$ for 30 mins or longer resulted in a decrease in greening and an increase in yellow color of ground garlic.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.379-387
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• 1991

The effects of organic acids (acetic, citric and lactic acids) treatment on microbial spoilage of chilled beef were studied during aerobic storage at $4^{\circ}C$ for 11 days. The organic acids had definite effects on the delay of the development of off-odor and slime of chilled beef. When chilled beef slices were treated with 1, 2, 3 and 4% of organic acids, off-odor was developed 1, 2, 3 and 5 days later than control, respectively, regardless of the kinds of organic acid. The slime was produced two days after the day of off-odor development in $1{\sim}3%$ organic acid-treated chilled beef, but no slime was produced on chilled beef treated with 4% organic acid. The off-odor was detected organoleptically when pH and number of microorganisms of chilled beef were, $5.6{\sim}5.8\;and\;0.8{\times}10^7{\sim}1.8{\times}10^7\;cell/cm^2$, respectively, and slime was observed when pH and number of microorganisms of chilled beef were $5.9{\sim}6.2\;and\;2.0{\times}10^7{\sim}6.0{\times}10^7\;cell/cm^2$, respectively, in control and treated groups.

• Journal of Hydrogen and New Energy
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• v.13 no.4
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• pp.321-329
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• 2002

Clostridium butyricum, Lactobacillus amylophillus, Lactobacillus amylovorus, Lactobacillus acidophillus, AI-9 produced hydrogen and /or organic acids using glucose, lactose and starch at the anaerobic culture conditions. Cl. butyricum NCIB 9576 evolved 1,700 ml H2/L-culture broth and accumulated butyric acid, acetic acid, propionic acid and ethanol in its culture broth when lactose was used as a carbon source during 24 hrs of fermentation. L. amylovorus ATCC 33620 accumulated lactic and acetic acids and some reducing sugars when starch was used as a carbon source without hydrogen production. Instead of starch as a carbon source, L. amylovorus ATCC 33620 produced lactic acid from algal biomass during fermentation and the acid-heat or freeze-thaw pretreatment of algal biomass accelerate the lactic acid fermentation.

• Biomedical Science Letters
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• v.10 no.3
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• pp.293-298
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• 2004

This study was performed to compare the growth rates, cellular fatty acid compositions and morphology by using electron microscope of Escherichia coli (E. coli) grown in various conditions including different concentrations of phenol, CdCl₂ and HgCl₂. Ninety eight E. coli strains were isolated from Naktong river and human feces. The content of unsaturated fatty acids, especially 16:1ω7c and 18:1ωc increased as the concentration of phenol and CdCl₂ increased. The content of unsaturated fatty acid increased up to 50 ppb of HgCl₂, but decreased at 75 ppb of HgCl₂. There were more unsaturated fatty acids than saturated fatty acid in the presence of toxic substances. However, the ration was reversed when the affected E. coli was transferred to toxic substance free fresh trypticase soy broth medium. Also, by using transmission electron microscope these cells were observed to various morphological deformation by heavy metals and their deposition on the surface. From these results, we suggested that the changes of major fatty acids composition and morphology of E. coli may be considered to indicate contaminated levels of heavy metals or organic solvents. The information presented here may be useful in predicting effects of heavy-metal and organic solvent contamination in streams and provides a basis for further studies of metal or organic solvent effects on microbial communities.

• Journal of the Korean Chemical Society
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• v.16 no.6
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• pp.354-360
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• 1972

Formation of the complexes of barium, strontium and calcium ions with dibasic organic acid ions in dilute solution was studied at room temperature, utilizing the equilibrium exchange technique which involved the uses of radioactive alkaline earth metal ions and cation excbange resin. The organic acids used in this study were succinic and tartaric acids, and the solvents used were water, 20 % acetone-water and 20 % ethanol-water. The pH of the solutions was controlled to 7.2∼7.4, and the ionic strength of the solutions was kept at approximately 0.1. The experimental results indicated that the alkaline earths formed one-to-one complexes in solution with the dibasic acids examined, and that the relative stabilities of the complexes increased in the order: $Ba^{++}; succinic

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.75-82
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• 2006

This study was carried out to investigate the changes of free sugars, non-volatile organic and fatty acids in flue-cured leaf tobacco during aging. The threshed leaf tobacco(B1O and C1L) produced in 2002 crop year was aged for 21 month in warehouse of Oc-Cheon Leaf Tobacco Processing Factory. The leaf tobacco were sampled at three month intervals for analysis of free sugars, non-volatile organic and fatty acids. The major free sugars of flue-cured were glucose and fructose regardless of tobacco grades. After aging period of 21 months, the contents of glucose and fructose showed a tendency to slightly decrease, and there was no appreciable change in the contents of sucrose in B1O and C1L grades. The major compound of non-volatile organic acid and fatty acid were malic, oxalic and citric, linolenic, linoleic and palmitic acid regardless of tobacco grade. After aging period of 21 months, the contents of malic, malonic, oxalic and fumaric acid showed a tendency to slightly decrease, whereas succinic acid was slightly increased, and maleic acid was not changed in B1O and C1L grades. The decreases in fatty acid contents in B1O and C1L grade tobacco loaves after 21 month aging were 16.5% and 9.8%, respectively. The decreases in linolenic acid contents in two grades were the highest, showing 22.1% and 12.0% reduction after 21 month aging.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1177-1185
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• 2003

The contents of organic acids in traditional and modified fermented foods were compared, and propionic acid produced during fermentation was investigated. Organic acids in traditional and modified soy sauces were lactic acid, acetic acid, citric acid, formic acid, succinic acid and oxalic acid while propionic acid was found in traditional soy sauces only. Similarly, lactic acid, acetic acid, citric acid, oxalic acid, formic acid, succinic acid and propionic acid were found in traditional and modified soy paste. The organic acids in traditional and modified kochujang were citric acid, acetic acid, formic acid, lactic acid, malic acid, oxalic acid and succinic acid while propionic acid was not found in modified kochujang. The major organic acid in persimmon and commercial (fermented) vinegars was acetic acid. Propionic acid was uniquely found in persimmon vinegars. Also, content of tannic acid in persimmon vinegars was 366.9 ∼ 909.8 mg%.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.278-282
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• 1979

Sugars and organic acids in Korean hot pepper fruit (C, annuum L.) according to its portions, pericarp, seeds and placenta, were determined by gas liquid chromatography (GLC). ${\alpha}-\;and\;{\beta}-fructoses,\;{\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose and maltose were identified. Major sugar in pericarp was fructose, while those in seeds and placenta were surose and fructose. Amount of free sugars in seeds was higher than that in pericarp or placenta. Succinic, fumaric, malic, tartaric, citric and quinic acids were found. Citric acid was a major organic acid found in pericarp and placenta. The amount of each identified organic acid, however, was similar in seeds. Quantity of total organic acids identified in pericarp or placenta was higher than that in seeds.

• Journal of fish pathology
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• v.28 no.3
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• pp.117-123
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• 2015

Economic loss by soft tunic syndrome of edible ascidian, Halocynthia roretzi has become a serious problem. Recently, it has discovered that the cause of this syndrome is infection by a protozoan parasite Azumiobodo hoyamushi. However, only a few studies have been conducted to control this parasitic disease. In a previous research, non-specific disinfectants have been found to be effective in controling the causative parasite. In an attempt to eradicate this causative parasite, organic acids were tested in this study to evaluate their in vitro and in vivo efficacy. In vitro tests showed that 8 different organic acids used in this study were moderately or highly effective with protozoan-killing effects ($EC_{50}=153{\sim}275{\mu}g/ml$). Despite weak in vivo penetration of organic acids into the tunic tissues, treatment with high concentration reduced the mortality of ascidian caused by infection the parasite, indicating that we might be able to develop a disinfection method using environmentally-friendly organic acids.