• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.832-837
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• 1989

It has been suggested that medium chain fatty acid(MCFA) may be toxic to yeast and bacteria and thus play a role in the inhibition of alcoholic and malolactic fermentations and also important contributors to wine flavour We measured, by the use of GLC, the concentrations of octanoic, decanoic and dodecanoic acids produced by 12 wine yeast strains during the alcoholic fermentation of a grape juice-like medium. In general, there was a high production of MCFA at first, dropping dramatically later. The formation of MCFA is largely dependent on yeast strain but it also depends upon temperature, sugar concentration, stirring and carbon dioxide sparging.

• Journal of the Korean Magnetics Society
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• v.3 no.3
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• pp.234-240
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• 1993

The water-based magnetic fluids were prepared with the synthesized ultrafine magnetite, dodecanoic acid as surfactant. Characteristics of synthesized ultrafine magnetite were investigated with X-ray Diffraction Pattern, Transmission Electron Microscope, Vibrating Sample Magnetometer and BET analysis. Dispersion characteristics of water-based magnetic fluids were investigated in relation to amounts of surfactant, pH and solid content.

• Journal of Microbiology
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• v.39 no.2
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• pp.139-141
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• 2001

Medium-chain length polyhydrexyalkanoic acids (MCL-PHAs) degrading bacterium was isolated from the soil. The bacterium was identified as Janthinobacterium lividum by its biochemical properties, cell membrane fatty acids composition, and 16S rDNA sequence analysis. The bacterium showed a similarity of 0.911 with J. lividum according to the cell membrane fatty acids analysis and a similarity of 97% in the 16S rDNA requence analysis. Culture supernatant of the bacterium skewed the highest depolymerase activity toward polyhydroxynonanoic acid (PHN) that did not degrade the poly-$\beta$-hydroxybutyric acid (PHB). The esterase activity was also detected with p-nitrophenyl (PNP) esters of fatty acids such as PNP-dodecanoic PNP-dodecanoic acid, PNP-decanoic acid, and PNP-hexanoic acid.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.351-355
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• 2002

Volatile compounds of kimchi-flavored steak sauce were isolated using simultaneous steam distillation and solvent extraction methods and identified by matching mass spectrum and retention index (RI) with the reference data. Twenty-three compounds including five aldehydes, four alcohols, four acids, three sulfur-containing compounds, one ketone, and six others were identified, among which the most abundant compound was eugenol. Sulfides such as dimethyl dis- and trisulfides, and acids such as acetic and dodecanoic acids showed strong effects on the kimchi flavor. Aroma extract dilution analysis with three fold dilution factor shown in over the FD value 34 identified 2-butanal, 2-pentylfuran, methyl-2-propenyl disulfide, and 2-furanmethanol. Strong good aroma was detected in the RI range between 1030 and 1357, bad aroma in RI 1561, sweety aroma in RI 2057, clover aroma of eugenol in RI 2122, and rancid flavor in RI 2251.

• Journal of Environmental Science International
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• v.5 no.5
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• pp.555-560
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• 1996

The toxic substances (endotoxins) from the bacterial cell walls were extracted by using incubator, centrifuge, UV-Vis spectrophotometer, and their fatty acid compositions were analyzed by Gas Chromatography. The lethal toxicities and pyrogenic activities of toxic substances were tested and the results were compared each other. The results of fatty acid analyses showed that the major fatty acid of the toxic substance was tetradecanoic acid for Vibrio vulnificus, dodecanoic acid for Escherichia coli, and decanoic acid for Salmonella typhimurium. These three fatty acids were the main fatty acids ofr three toxic substances (more, than 70%). The unique points in the fatty acid compositions were that tetradecanoic acid was composed as important one (37.15%) for V. vulnificus and that the amount of hexadecanoic acid was very small (below 2%) for three toxic substances. The lethal toxicity in ICR mice of toxic substance from V. vulnificus (LD50 was 52.5 mg/kg) was similar to that of E. coli (56.5mg/kg), but weaker than that of S. typhimurium (37.5mg/kg). Toxic substance from V. vulnificus was more pyrogenic in rabbit than that from E. coli, but less than that from S. typhimurium.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.54-63
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• 1993

Some emulsified 1, 2-disubstituted imidazolinium salts were synthesized by quaternization of 1, 2-disubstituted imidazoline which had been prepared by the reaction of dodecanoic acid with tetraethylenepentamine. 2-Docosamido-2'-docosanoyloxydiethylamine was prepared by the reaction of docosanoic acid with hydroxylethylethylenediamine. Then, some emulsified fatty carbamide salts were also synthesized by quaternization of fatty carbamide which had been prepared by the reaction of urea with the 2-docosamido-2'-docosanoyloxydiethylamine. Some softners were prepared by blending of these salts mentioned above. These softners were treated on acrylic fiber, then several properties were measured. As the results, softening and lubricating properties are good and a little antistatic property was observed. The synthesized softners were also proved as a durable softner by means of the several experiments : bending resistance test and measurements of feeling change with washing according to the pH changes. The surface structure of acrylic fibers treated with the softner were characterized by SEM.

• Journal of Plant Biotechnology
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• v.47 no.1
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• pp.100-106
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• 2020

Coix lacryma-jobi (Hanjeli) is known to posses anti-microbial properties. Therefore, phytochemical compounds of C. lacryma-jobi have been studied to produce novel antimicrobial agents as treatments against antibiotic-resistant bacteria.The objective of this study was to determine the phytochemical composition and antibacterial activity of the C. lacryma-jobi oil against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The phytochemical composition of the oil was determined via gas chromatography mass spectrophotometry (GC-MS). Moreover, agar disk and agar well diffusion were employed to screen the antibacterial activity of the oil. An agar well diffusion test was implemented to determinate MIC's (minimum inhibitory concentrations). Dodecanoic acid, tetradecanoic acid, 2,3-dihydroxypropylester, 1,3-dioctanoin, N-methoxy-N-methyl-3,4-dihydro-2H-thiopyran6-carboxamide, propanamide, 5-Amino-1-(quinolin-8-yl)-1,2,3-triazole-4-carboxamide, and pyridine were identified in the C. lacryma-jobi oil. The MIC value of the oil was 0.031 g/L and the MBC of the oil was 0.125 g/L effective in all test bacteria. Dodecanoic acid displayed inhibitory activity against gram-positive and gram-negative bacteria. Therefore, our research demonstrated C. lacryma-jobi (Hanjeli) oil exhibited antibacterial activity against E. coli, S. aureus, and B. subtilis. These research suggest that C. lacryma-jobi root oil could be used for medicinal purposes; however clinical and in vivo tests must be performed to evaluate its potential as an antibacterial agent.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.749-753
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• 1998

Methoxy polyoxyethylene dodecanoates, kinds of nonionic surfactants, could be obtained from addition of ethylene oxide (5, 7, 9, and 12mol) with fatty acid methyl ester utilizing solid catalyst, metal oxide. Because ethylene oxide (EO) couldn't react directly in acid or alkali catalyst with dodecanoic acid methyl ester (DME) that had no active hydrogen, the reaction to add EO was carried out using active solid catalyst. By using IR, HPLC and $^1H$ NMR analysis, structural confirmation of methyl polyoxy ethylene dodecanate showed high yield ranging from 93 to 97%. EO unit mol number of reacted products was 5.2, 7.1, 9.2 and 12.1 mol respectively. Also, EO adduct distrobution of ethoxylated methyl laurate (MPD) had normal distribution curve like polyoxyethylene alkyl ether (AE).

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.728-732
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• 1998

The purpose of this study was to identify off-flavor compounds in sea mustard and rice syrup sold in the markets. Naphthalenes such as naphthalene, 2-methylnaphthalene, 1-methylnaphthalene, 2,6-dimethylnaphthalene, 1,5-dimethylnaphthalene, 1,8-dimethylnaphthalene, 2,7-dimethylnaphthalene, 1,4,6-trimethylnaphthalene, 2,3,6-trimethylnaphthalene etc., were present in sea mustard, while free fatty acids such as butanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid and 2-furanmethanol, 2-furancarboxaldehyde etc. in rice syrup. The former (naphthalenes) have been supposed to be contaminents from paint of ship and the latter (free fatty acids) derived from deteriorated rice for saccharification. From the results of the samples studied, formation of their off-flavor compounds seems to be related with the condition of storage, the process of production and circulation in the markets.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.735-738
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• 2001

Metabolically engineered Escherichia coli strains harboring a plasmid containing a novel artificial polyhydroxyalkanoate (PHA) operon consisting of the Aeromonas PHA biosynthesis related genes and Ralstonia eutropha reductase gene were developed for the production of poly(3-hydroxybutyrate-co-hydroxyhexanoate) [P(3HB-co-3HHx)] from dodecanoic acid. By applying stepwise reduction of dissolved oxygen concentration (DOC) during the fermentation, the final dry cell weight, PHA concentration, and PHA content of 79 g/L, 21.5 g/L, and 27.2 wt%, respectively, were obtained in 40.8 h, which resulted in the PHA productivity of 0.53 g/L/h. The 3HHx fraction slowly increased during the fed-batch culture to reach a final value of 10.8 mol%. The 3HHx fraction in the copolymer could be increased by three fold when the Aeromonas hydrophila orfl gene was co-expressed with the PHA biosynthesis genes.