• Applied Chemistry for Engineering
• /
• v.21 no.5
• /
• pp.509-513
• /
• 2010

Recently, an amount of waste electronic devices such as LED and trichromatic fluorescent lamp has increased with the development of electronic industry. Reportedly, rare earth metals such as yttrium and europium have been discovered in the waste electronic devices. In order to improve the selectivity of yttrium and europium, the effects of the following factors on recovery experiment have been considered : i) fatty acids with various alkyl chain lengths, ii) the concentration of extractant, and iii) pH. The results show that the extraction efficiencies decrease at the same pH with decreasing the concentration of extractant and so $pH_{0.5}$ (That value of pH in an aqueous phase at which the distribution ratio is unity at equilibrium: 50% of the solute is extracted (E = 0.5) only when the phase ratio is unity.) moves into higher pH. The highest selectivity of yttrium and europium was obtained with tetradecanoic acid as extractant. The extraction mechanism of yttrium and europium was varied with the change of concentration of the tetradecanoic acid. $MR_3$single-species was formed from the yttrium and europium ion in the extractant concentration less than 0.1 M. On the other hand, the yttrium or europium ion is solvated with three molecules of tetradecanoic acid monomer like $MR_3{\cdot}$ 3RH in the extractant concentration more than 0.1 M.

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

• Food Science and Preservation
• /
• v.14 no.4
• /
• pp.351-355
• /
• 2007

Solvent-extracted volatile components from dry powder prepared from Citrus unshiu products such as immature Citrus unshiu (PCU), mature Citrus unshiu (MCU), Citrus unshiu peel (CUP), and citrus juice processing wastes (CJPW), were examined. Also, solvent-extracted volatile components from mushroom mycelia of Pycnoporus coccineus (PC), Lentinus edodes (LE), Pleurotus eryngii (PE), Hericium coralloides (HC), Panellus serotinus (PS), and Ganoderma lucidum(GL), all cultivated using citrus pulp solid media, were assayed. Twenty-nine volatile components were identified in dry powder prepared Citrus unshiu and 18 volatile components were characterized from mushroom mycelia. Of these, ${\beta}-elemene$, germacrene-D, and ${\delta}-cadinene$, were derived from CJPW, but caryophyllene, hexadecanoic acid, decanoic acid, and tetradecanoic acid were synthesized by mushroom mycelia.

• Applied Biological Chemistry
• /
• v.38 no.6
• /
• pp.546-548
• /
• 1995

An attempt was made to determine the volatile flavor components of Auricularia polytricha mushroom. Essential oils from the dried mushroom were isolated by a simultaneous steam distillation-extraction(SDE) method using diethyl ether as a solvent. Total 30 components were identified bt GC-MS from the in essential oils including 11 acids, 10 alcohols, 5 aldehydes, 3 ketons, 1 other components. The major volatile components were heaxadecanoic acid(16.74%), benzeneethanol(7.77%), pentadecanoic acid(7.59%), dihydro-5-penhtyl-2-(3H)-furanone acid(4.28%), tetradecanoic acid(3.37%), pentanoic acid(3.38%) and 1-octen-3-ol(1.26%).

• Applied Biological Chemistry
• /
• v.34 no.2
• /
• pp.102-109
• /
• 1991

Quality of three kinds of honey from acacia, chestnut and polyflower sources, was evaluated by physicochemical and GC-MS analysis in respect to some chemical composition. The average contents of moisture, ash, HMF(hydroxy methyl furfurol) and free acidity were 19.7% , 0.028% , 18.28mg/kg and 8.85meq/kg , respectively, in acacia honey, 19.1% , 0.05% , 18.47mg/kg and 10.24 meq/kg , respectively, in polyflower honey, and 18.9% , 0.050% , 20.21mg/kg, 12.28meq/kg respectively, in chestnut honey. The average contents of glucose and fructose ranged from 31.0 to 32.0% and from 35.0 to 36.0% , respectively, in all three kinds of honey. The average ratio of fructose to glucose was 1.14 in all three kinds of honey. Fatty acid composition in honey identified by GC-MS analysis was dodecanoic acid, 10-hydroxy-2-decanoic acid, 6,9-undecadienoic acid, tetradecanoic acid, 12-(acetyl oxy) -9-octadecenoic acid and 14-octadecenoic acid. The content of 10-hydroxy-2-decenoic acid was about 10% in three kinds of honey.

• Journal of the Korean Chemical Society
• /
• v.35 no.1
• /
• pp.85-89
• /
• 1991

Various sterols and uncommon fatty acids have been isolated from the three species of Korean marine sponges. Odd-numbered pentadecanoic, heptadecanoic methyl ester and branched 12-methyltetradecanoic, 14-methylpentadecanoic, 15-methylhexadecanoic and 14-methylhexadecanoic methyl ester were isolated along with common tetradecanoic and hexadecanoic methyl ester from Heteropiidae sponge Vosmaeropsis japonica Hozawa collected from Sohuksan island of the Korea sea. Futher elution with more polar solvent gave 5${\alpha}$-cholestan-3${\beta}$-ol along with minor amount of ergost-25-ene-3${\beta}$,5${\alpha}$,6${\beta}$-triol. On the other hand, marine sponge Hymeniacidon sinapium collected from Yesu Dolsan island of the Korea sea was shown to contain 5${\alpha}$-cholestan-3${\beta}$-ol, along with minor amount of cholesterol, palmitic, palmitoleic, oleic, stearic, linolenic, and arachidonic acid ethyl ester. Unknown marin sponge collected from the same region was shown to contain large amount of tetradecanoic tetradecyl and hexadecyl ester and cholesteryl acetic and fatty acid ester.

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

• Korean Journal of Microbiology
• /
• v.25 no.1
• /
• pp.67-72
• /
• 1987

Cellular fatty acid composition of eight strains, indluding six strains of Comamonas terrigena, and two type strains of Pseudomonas acidovorans, and P. testosteroni was determined by gas-liquid chromatography. Almost the same composition was found in all the strains tested, and hexadecanoic acid, hexadecenoic acid, and octadecenoic acid were accounted more than 70% of total fatty acid. However, P. testosteroni differed from C. terrigena and P. acidovorans by the presence of comparatively large amonuts of 2-hydroxy-hexadecanoic acid, and C. terrigena contained three to eight times as much tetradecanoic acid in P. acidovorans and P. testosteroni. According to the similarity values calculated on the basis of fatty acid composition, C. terrigena strains were divided into three groups differentiated in the requirement of growth factors, and C. terrigena, P. acidovorans, and P. testosteroni strains occupied separate position each other in the dendrogram.

• Applied Biological Chemistry
• /
• v.46 no.3
• /
• pp.214-219
• /
• 2003

The fractions extracted with methylene chloride from colored rice seeds of 19 cultivars were prepared to examine the correlationties of both antimutagenicity and antioxidiativity with physiological functionalities. The data revealed a positive correlation of the antimutagenicity with the content of $(3.{\beta},22Z)-Acetate-stigmasta-5,22-dien-3-ol$, 24-Oxocholesterol acetate, 6(E),8(E)-Heptadiene, and Eicosane. For antioxidativity, electron donating ability to DPPH radicals exhibited a positive correlation with the content of (24R,25S)-Aplysterylacetate, however, negative correlations were found between scavenging activity toward hydroxyl radicals and the content of either Tetradecanoic acid or Methyl ester-hexadecanoic acid, $(3.{\beta},24S)-Stigmast-5-en-3-ol$, respectively. In addition, a positive correlation was detected between the inhibitory effect of the fractions and the content of $(3.{\beta},24S)-Stigmast-5-en-3-ol$, however, a negative correlation with the content of 3',3'-Dimethylspiro [acridane-9,1'-indane], $(3.{\beta})-24-Methylene-9,19-cyclolanostan-3-ol$, and some other compounds was observed, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.2
• /
• pp.208-213
• /
• 1995

Andong Sikhe in Korea was prepared and fermented at 5$^{\circ}C$ and the taste and flavor compounds were evaluated. Major flavor components were identified by gas chromatography-mass spectrometer as camphene, sabinene, 1-(1, 5-dimethyl-4-hexyl)-4-methyl-benzene, alpha-zingibirene, farnesene, 2, 6-bis(1, 1-dimethylethyl)-4-metethyl-phenol, beta-sesquiphellandrene, calalene, tetradecanoic acid, and 9, 12-octadecanoic acid. The concentration of nonvolatile organic acid such as lactic acid, oxalic acid and citric acid were 18.10mg/100g, 1.04mg/100g and 1.37mg/100g, respectively, and those of other nonvolatile organic acid were a little. The pH and acidity of Andong Sikhe were 4.06 and 0.32 during fermentation and storage.