• KSBB Journal
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• v.29 no.2
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• pp.118-123
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• 2014

It was confirmed that malodor connected with an air-conditioner in an automobile is caused by microbial volatile organic compounds (MVOCs) produced by microorganisms getting into an air-conditioner when it is operating. Chemicals such as hydrogen sulfide, dimethyl sulfide, nbutyric acid, n-valeric acid, iso-valeric acid, n-octanol and toluene were detected above the odor threshold inside the automobile. The characteristics of a funky odor in the air blown into the automobile were due to detected sulfur compounds (hydrogen sulfide and dimethyl sulfide). Dimethyl sulfide was produced by microorganisms such as Aspergillus versicolor, Methylobacterium aquaticum, Herbaspirillum sp. and Acidovorax sp. In addition, the characteristics of a sour odor in the air blown into the automobile were due to detected organic acids (n-butyric acid, n-valeric acid and iso-valeric acid). N-valeric acid and iso-valeric acid were generated from Aspergillus versicolor, while iso-valeric acid was produced by Methylobacterium aquaticum. In addition, the odor intensity of the air blown into the automobile was affected by the concentration of detected sulfur compounds and organic acids. On the other hand, it is estimated that chemicals such as hydrogen sulfide, n-octanol and n-butyric acid detected in the air blown into the automobile were produced by non-identified species of microorganisms.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.2
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• pp.107-113
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• 2000

This study was carried out to investigate the changes in composition of the non-volatile organic acid, fatty acid and polyphenolic compounds during air-curing in burley tobacco leaves, and the effect of curing methods on the contents in air-cured leaves. The air-cured variety, (Nicotiana tabacum cv KB108) was normally grown at the Chonju tobacco experiment station in 1998. Plants designated for the each curing methods were harvested on the same date, and the ripe leaves for primed curing were harvested at the tenth leaf position from the top on the stalk. The major compounds of non-volatile organic acid and fatty acid were malic, citric, oxalic, palmitic, and linolenic acid. The concentrations of malic acid, unsaturated fatty acids, chlorogenic acid and rutin in cured leaves were remarkably decreased during curing, while citric acid was increased. The changes of these compounds showed the similar pattern during both primed and stalk curing. In connection with curing methods, the contents of malic, linoleic and linolenic acid were higher in excessive cured leaves than those in primed cured or stalk cured leaves, while the content of citric acid was lower in excessive cured leaves than that in primed cured or stalk cured leaves.

• Korean journal of food and cookery science
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• v.7 no.1
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• pp.27-34
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• 1991

This study attempted to set up reasonable extraction time of Omija that was put in water for the various components to soak out. Changes of free sugars, organic acids, reducing sugar, total acid and tannin in Omija with various extraction times were investigated (together with the analysis of each components in Omija fruit). 1. High Performance Liquid Chromatography showed fructose, glucose, and sucrose to be the major free sugars of the Omija fruit. Free sugars and reducing sugar value in Omija beverage increased gradually in according with the extraction time, and marked 75.6% per total free sugars and 82.1% per total reducing sugar at 12 hours. 2. Gas Chromatography showed lactic acid, oxalic acid, fumaric acid, levulinic acid, succinic acid, malic acid, citric acid and pyroglutamic acid to be the major organic acids of the Omija fruit. Organic acids and total acids value in Omija beverage increased gradually on proportion to extraction time, and marked 97.0% per total organic acids at 9 hours and 79.0% per total acids at 12 hours. 3. Tannin content in Omija beverage was increased when extraction time was longer but it showed a low percentage as compared with the reducing sugar and total acid. Tannin content marked 48.8% per total tannin at 12 hours. 4. Sensory evaluation revealed that !1 hours of extraction produced the best quality products based in taste, flavor, color and over-all acceptability, considering the data, it seems possible to conclude that the optimum of time for extraction of Omija to water is 9 hours.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1324-1326
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• 2004

In previous studies, we isolated an isogenic LPS mutant of Bradyrhizobium japonicum 61A101C, which was completely devoid of O-polysaccharide and had altered cell surface characteristics. Subsequently, the mutated gene was identified, cloned, and used to complement the LPS mutant strain JS314 to restore the phenotype. Since it has been reported that in Escherichia coli LPS O-polysaccharide is involved in resistance to an organic acid such as acetic acid under low pH (Barna et al., Molecular Microbiology 43: 629-640, 2002), we compared the organic acid resistance of the three B. japonicum strains; wild-type 61A101C, the LPS mutant JS314, and the complemented strain to determine whether the role of O-polysaccharide in the resistance to organic acid could be generalized. Growth of all three strains was inhibited by the presence of 3 mM acetic acid under acidic condition (pH 5.5). To our surprise, however, in the presence of 2 mM acetic acid, wild-type and the complemented strains did not grow while the $LPS^-$ mutant showed a significant growth. Therefore, unlike in E. coli, the lack of O­polysaccharide of LPS appears to render B. japonicum more resistant to organic acid.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.59-65
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• 2009

The antimicrobial activity-possessing materials were screened in the cell free supernatant (CFS) of fourteen lactic acid-fermenting strains isolated from pig's intestine. Each cell free supernatant of cultured strains was treated with various proteinases, heat, and/or alkali (NaOH). The antimicrobial activities were remained even after the enzyme and heat treatment but disappeared after neutralization with 1M NaOH, implying that the materials would be organic acids rather than proteins. Further purification of CFS through solid phase extraction using Sep-pak $C_{18}$ Cartridges and high performance anion exchange chromatography using Bio-LC system revealed that four organic acids, such as oxalic acid, citric acid, lactic acid, and acetic acid, were the main materials for the activity. Lactic acid was the highest amount in all organic acids, ranging from 54% to 77%. This strongly implies that the lactic acid would be the primary material for the antimicrobial activity in all tested strains.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.922-927
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• 2005

Total and individual organic acid contents of Malus domestica Borkh, cultivars, Tsugaru, Fuji Jonathan (Hong-Ok), and New Jonagold(Sin-Heung) apples, were investigated. Average titratable acidities measured by titration method and total organic acids content determined by HPLC were 241.64-444.52 and 364.23-680.80mg%, respectively. Average total organic acid contents were Jonathan 630.80mg%, New Jonagold 471.04mg%, Fuji 403.80mg%, and Tsugaru 364.23mg%, Contents of DL-malic, citric, fumaric, and quinic acid were 351.98 (Tsugaru)-579.88mg% (Jonathan), 2.14 (Fuji)-12.95mg% (Jonathan), 0.012 (Fuji)-0.060mg% (Jonathan), and 8.91 (Tsugaru)-14.20mg% (Fuji), respectively. Succinic acid was detected only from Jonathan (27.53mg%) and New Jonagold (5.20mg%), while maleic acid was not detected from all cultivars. Ratio of L-malic acid and DL-malic acid contents were 0.98-1.02 in all apple cultivars.

• Journal of Nutrition and Health
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• v.11 no.3
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• pp.21-24
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• 1978

In order to estimate the chemical composition of Raspberry (IR Crataegifalius), the free amino acids were analyzed by amino acid autoanalyzer, and organic acids contents were determined by gas chromatography and the free sugars were detected by paper chromatography. The results obtained were as follows: 1) The free amino acids found in Raspberry were 18 kinds of them, especially, all essential amino acids were showed, and lysine was abundant among them, consequently it was found that the composition of amino acids in Raspberry is more superior than those of the other fruits. 2) The organic acids in Raspberry were found citric acid, tartaric acid, malic acid and fumaric acid. It was found that the quantity of the organic acids was less than those of other common fruits. 3) Sugar such as glucose, fructose, maltose and mannose were detected by paper chromatography.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.409-414
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• 2009

In this study, the quality of chicken breasts from organically reared chickens was compared with that of chicken breasts from conventionally reared chickens. Broilers were raised in an indoor pen with conventional and organic production system, respectively. The diet formulation for the organically reared chickens and the production density were in accordance with the guidelines for organic chicken products. Twenty birds from each group were slaughtered and their breasts were obtained for analysis. The organic chicken breasts had a higher cooking loss, and waterholding capacity, and a lower shear force (p<0.05) compared to the conventional chicken breasts. The organic chicken breasts also showed higher $a^{\ast}$ and $b^{\ast}$ values and myoglobin contents compared with the conventional chicken breasts (p<0.05). In the fatty-acid analysis, the organic chicken breasts resulted in higher polyunsaturated fatty acid (PUFA) and unsaturated fatty acid contents, and a higher PUFA-saturated fatty acid ratio.

• Asian Journal of Atmospheric Environment
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• v.3 no.1
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• pp.42-51
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• 2009

Saturated n-dicarboxylic acids ($C_2-C_7$, $C_9$), unsaturated dicarboxylic acids (maleic, fumaric, phthalic acid), ketocarboxylic acids (pyruvic, glyoxylic acid), and dicarbonyls (glyoxal, methylglyoxal) were determined in size-segregated samples with a high-volume Andersen air sampler at a suburban site in Saitama, Japan, May 12-17 and July 24-27, 2007 and January 22-31, 2008. The seasonal average concentrations of these detected organic acids were 670 $ng/m^3$, accounting for about 4.4-5.7% (C/C) of water-soluble organic carbon (WSOC) and 2.3-3.6% (C/C) of organic carbon (OC). The most abundant species of dicarboxylic acids was oxalic acid, followed by malonic, phthalic, or succinic acids. Glyoxylic acid and methyglyoxal were most abundant ketocarboxylic acid and dicarbonyl, respectively. Seasonal differences, size-segregated concentrations, and the correlations of these acids with ambient temperatures, oxidants, elemental carbon (EC), OC, WSOC, and ionic components were also discussed in terms of their corresponding sources and possible secondary formation pathways. The results suggested that photochemical reactions contributed more to the formation of particulate organic acids in Saitama suburban areas than did direct emissions from anthropogenic and natural sources. However, direct emissions of vehicles were also important sources of several organic acids in particles, such as phthalic and adipic acids, especially in winter.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.907-912
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• 1999

In this study, removal effect of residue pesticides on vegetable and fruit using organic acid salt in alkali solution were investigated by gas chromatography and measurement of detergency. Generally, for the removal methods of residue pesticides and oily pollution were used chemical detergent or organic solvent. Specially, in our experiment, we only used material of food additives and trisodium citrate were superior to other organic acid salt. It was investigated that removal effect of pesticides was superior to chemical detergent.