• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.102-104
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• 1989

The characteristics of stearic acid and PDA (pentacosaDiyonicAcid) LB films were studied using the XRD spectra for regularity of layers and ellipsometer for the total thickness of multilayer films. From the experiments of varying the PH and temperature, it was found that the stability of monolayer on the water subphase was very sensitive to its PH and temperature. The optimum condition of PH for the stable stearic acid LB film was 6$\sim$6.5. The PDA LB films were stable at the lower temperature than room temperature: we obtained very uniform PDA LB films at 12$^{\circ}C$.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.5
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• pp.379-384
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• 1999

Langmuir-Blodgett(LB) films which have high ordered orientation and ordering structure are fabricated by LB method which deposit the ultra-thin films of organic materials at a molecular level. The electrical characteristics of stearic acid LB ultra-thin films for the horizontal direction were investigated to develop the gas sensor using LB ultra-thin films. The optimal deposition condition to deposit the LB ultra-thin films was obtained from $\pi-A$ isotherms and the deposition status of stearic acid LB ultra-thin films was verified by the measurement of deposition ratio, UV-absorbance, and electrical properties for LB ultra-thin films. The conductivity of stearic acid LB ultra-thin films for horizontal direction was about $10_{-8}[S/cm]$. The activation energy for LB ultra-thin films with respect to variation of temperature was about 1.0[eV], which was correspond to semiconductor material. The response characteristics for organic gas were confirmed by measuring the response time, recovery time, and reproducibility of the LB ultra-thin to each organic gas. Also, the penetration and adsorption behavior of gas molecule were confirmed through the organic gas response characteristics of LB ultra-thin films with respect to temperature.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.8-15
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• 1986

This study was carried out to investigate changes of the lipid contents and the fatty acid composition in shank during heating time and frozen storage. 1. The total lipid contents of raw shank were about 3.57% and decreased stepwise during heating time 30, 60, 90 min and frozen storage(24hrs) The contents of neutral lipid, glycolipid and phospholipid were 70.71%, 6.36%, and 22.93% in raw shank, and neutral lipid contents were decreased, whereas Phospholipid contents were increased according to heating tide. In frozen storage, neutral lipid and glycolipid contents were increased, while phospholipid contents were decreased. 2. Lipids of shank possessed about 8 kinds of fatty acid as the constituent by gas-liquid chromatography analysis. The main fatty acids were oleic acid, palmitic acistearic acid and linoleic acid: the fatty acids of total lipids in raw shank were 43.48% of oleic acid, 23.13% of palmitic acid,12.00% of stearic acid and 6.75% of linoleic acid. Also the fatty acids were 43.32% of oleic acid, 23.26% of palmitic acid, 9.30% of stearic acid 2.15% of linoleic acid in neutral lipid, 22.63% of oleic acid, 8.44% of palmitic acid, 11.98% of stearic acid, 27.01% of linoleic acidin glycolipid, 39.38% of oleic acid, 15.89% of palmitic acid, 15.55% of stearic acid, 17.49% of linoleic acid in phospholipid. 3. The fatty acid pattern of total lipid, neutral lipid, glycolipid and phospholipid was not any changes, whereas there was a difference in the fatty acid contents: palmitic acid and stearic acid of total lipid were decreased in the 30 min and 60 min heating but increased in 90min heating, and linoleic acid of neutral lipid was increased stepwise during heating time and frozen storage. Also palmiict acid of glycolipid was increased gradually and linoleic acid in heating time 30, 60 min was higher than 90 min and frozen storage. Among fatty acids in phoapholipid, oleic acid was increased during heating time, while decreased in frozen storage, and linoleic acid was not any change but linolanic acid was increased. UFA/SFA of phospholipid was the highest when heating time was 60 min. From above results, it was found that when heating time was 60 min beneficial nutritionally, comparing with changes of fatty acid composition according to the heating time aid frozen storage.

• Current Research on Agriculture and Life Sciences
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• v.31 no.1
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• pp.45-50
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• 2013

Mutagenesis is used to study gene function and obtain new genetic resources for plant breeding. Soybean is an important oil crop in the world. Thus, to find new genetic resources, a mutation population was developed from the soybean cultivar Pungsannamul using 0.3% ethyl methane sulfonate. The variation of fatty acids was then evaluated among 892 M4 generation mutant lines selected from 3,774 mutant lines. While the wild type Pungsannamul showed 11.6, 3.4, 23.8, 53.3, and 7.8% for palmitic, stearic, oleic, linoleic and linolenic acid, respectively. the fatty acid variations in the mutant lines ranged from 7.4 to 19.7%, 2.2 to 13.0%, 14.7 to 49.0%, 31.8 to 63.9%, and 3.9 to 15.9% with an average of 10.8, 3.8, 25.3, 52.0, and 8.1% for palmitic, stearic, oleic, linoleic and linolenic acid, respectively. Thus, two mutation lines with higher plamitic acid, PE1542 (17.1%) and PE3058 (17.0%), one line with lower stearic acid, PE2166 (1.9%), one line with higher stearic acid, PE977 (12.7%), two lines with higher oleic acid, PE450 (44.4%) and PE2742 (47.7%), and two lines with lower linolenic acid, PE594 (4.6%) and PE1690 (3.7%), were selected from this study. The newly selected fatty acid variants will be good genetic sources for gene function analyses and breeding soybean varieties with altered fatty acids for various industrial and human food applications.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1110-1117
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• 2001

Responses of the rumen fungus, Neocallimastix frontalis RE1, to long chain fatty acid (LCFA) were evaluated by measuring gas production, filter paper (FP) cellulose digestion and polysaccharidase enzyme activities. LCFA (stearic acid, $C_{18:0}$; oleic acid, $C_{18:1}$; linoleic acid, $C_{18:2}$ and linolenic acid, $C_{18:3}$) were emulsitied by ultrasonication under anaerobic condition, and added to the medium. When N frontalis RE1 was grown in culture with stearic, oleic and linoleic acid, the cumulative gas production, gas pool size, FP cellulose digestion and enzymes activities significantly (p<0.05) increased at some incubation times(especially, exponential phases of fungal growth, 48~120 h of incubation) relative to that for control cultures. However, the addition of linolenic acid strongly inhibited all of the investigated parameters up to 120 h incubation, but not after 168 and 216 h of incubation. These results indicated that stearic, oleic and linoleic acids tended to have great stimulatory effects on fungal cellulolysis, whereas linolenic acid caused a significant (p<0.05) inhibitory effects on the cellulolysis by the rumen fungus. These results are the first report of the effect of LCFAs on the ruminal fungi. Further research is needed to identify the mode of action of LCFAs on fungal strains and to verify whether or not ruminal fungi have ability to hydrate unsaturated LCFAs to saturated FAs. There was high correlation between cumulative in vitro gas production and fungal growth (94.78%), FP cellulose degradation (96.34%), CMCase activity(90.86%) or xylanase activity (87.67%). Thus measuring of cumulative gas production could be a useful tool for evaluating fungal growth and/or enzyme production by ruminal fungi.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.4
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• pp.251-257
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• 1982

Fatty acid and sterol composition of soybean seedlings was investigated by treatment of light irradiation time. The results obtained were as follows; 1. In hypocotyl of seedlings, the proportion of linoleic and linolenic acid was in creased with increasing light irradiation time, while those of palmitic and stearic acid was decreased. 2. In root of seedlings, the proportion of palmitic and linolenic acid was decreased with increasing light irradiation time, but those of stearic and oleic acid was in creased 2 days after germination. 3. Throughout their growth, the main sterol of cotyledon was the stigmasterol but that of in hypocotyl and roots was sitosterol. 4. On 6 days after planting, the content of sitosterol was the highest in hypocotyl of seedlings recieved 24-hour irradiation. 5. The proportion of sitosterol in root was decreased with growth duration under the dark and 24 hour-irradiation condition while increased under 16 hour irradiation.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.279-284
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• 1996

Decay of the spin label attached to cytochrome c or to stearic acid has been measured by electron paramagnetic resonance (EPR) spectroscopy to monitor membrane oxidation induced by cytochrome c-membrane interaction. Binding of cytochrome c sequestered the acidic phospholipids and membrane oxidation was efficient in the order linoleic oleic>stearic acid for a fatty acid chain in the acidic phospholipids. The spin label on cyt c was destroyed at pH 7 whereas that on stearic acid embedded in the membrane was destroyed at pH 4, presumably due to different modes of cyt c-membrane interaction depending on pH. Interestingly, cyt c also interacts with phosphatidylethanolamine, an electrically neutral phospholipid, to cause rapid membrane oxidation. Both EPR and fluorescence measurements indicated that electrostatic interaction is at least partially responsible for the process.

• Journal of the Korean Magnetics Society
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• v.5 no.6
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• pp.956-962
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• 1995

본 연구에서는 포화지방산으로 피복된 초미립 마그네타이트(Magnetite, Fe$_{3}$ $O_{4}$) 중에 nonanoic acid가 용해되어 있는 알칼리 수용액을 첨가한 후, 이들 슬러리(slurry)를 건조하여 kerosene에 분산시켜 유상자성유체를 제조하였다. Stearic acid 첨가량에 따른 분산율의 변화를 조사한 결과 stearic acid 첨가량이 증가함에 따라 분사율은 증가하였으나, 2.6 * $10^{-2}$ mol 이상에서는 분산율이 78%로 감소하 였다. Stearic acid로 피복된 마그네타이트에 의해 유상자성유체제조시 분산안정제로서 사용된 nonanoic acid 첨가량에 따른 분산율의 변화를 조사한 결과 nonanoic acid 를 첨가하지 않은 경우 분산이 일어나지 않았으나, nonanoic acid를 첨가함에 따라 분산율은 급격히 증가하였다. 포화지방산을 계면활성제로 사용하여 흡착-유기상 분산 법에 의해 유상자성유체를 제조한 결과, $C_{12}$ ~ $C_{16}$ 지방산을 사용하여 유상자성유체를 제조할 경우 20% 내외의 분산율을 나타내었다. 분산제로서 Nonanoic acid를 사용하여 유상자성유체를 제조할 경우 $C_{10}$ 지방산으로 제조한 유상자성 유체는 분산이 일어나지 않았으나, C 사슬의 길이가 증가함에 따라서 분산율은 급격히 증가하였으며 $C_{15}$ 지방산 부터는 90% 이상의 분산율을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.5
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• pp.523-527
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• 1997

The fatty acid compositions of oocytes, follicular, oviductal and uterine fluids of pig and cow were analyzed using gas chromatography. Myristic (C 14: 0), palmitic (C 16: 0), palmitoleic (C 16: 1), stearic (C 18 : 0), oleic (C 18: 1), linoleic (C 18: 2), linolenic (C 18: 3) and arachidonic (C 20: 4) acids were identified as the common fatty acid constituents with little exception. Oleic acid composition was the highest (21.90 to 36.24%) in both pig and cow followed by palmitic (18.61 to 31.90%) and stearic (10.34 to 20.39%) acid. The three polyunsaturated fatty acids like linoleic, linolenic and arachidonic acids were detected in both pig and cow reproductive fluid samples. Myristic acid was not detected in pig oviductal fluid. Similarly, in cow oocytes myristic, palmitoleic and linolenic acids were not detected. Moreover, palmitic, stearic, oleic and linoleic acid comprised about 80% (73.74 to 88.00%) of the total fatty acids in the different samples analyzed in both animals.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.411-419
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• 2015

We previously demonstrated that bovine subcutaneous preadipocytes promote adipogenic gene expression in muscle satellite cells in a co-culture system. Herein we hypothesize that saturated fatty acids would promote adipogenic/lipogenic gene expression, whereas mono- and polyunsaturated fatty acids would have the opposite effect. Bovine semimembranosus satellite cells (BSC) and intramuscular preadipocytes (IPA) were isolated from crossbred steers and cultured with 10% fetal bovine serum (FBS)/Dulbecco's Modified Eagle Medium (DMEM) and 1% antibiotics during the 3-d proliferation period. After proliferation, cells were treated for 3 d with 3% horse serum/DMEM (BSC) or 5% FBS/DMEM (IPA) with antibiotics. Media also contained $10{\mu}g/mL$ insulin and $10{\mu}g/mL$ pioglitazone. Subsequently, differentiating BSC and IPA were cultured in their respective media with $40{\mu}M$ palmitic, stearic, oleic, or linoleic acid for 4 d. Finally, BSC and IPA were single- or co-cultured for an additional 2 h. All fatty acid treatments increased (p = 0.001) carnitine palmitoyltransferase-1 beta ($CPT1{\beta}$) gene expression, but the increase in $CPT1{\beta}$ gene expression was especially pronounced in IPA incubated with palmitic and stearic acid (6- to 17-fold increases). Oleic and linoleic acid decreased (p = 0.001) stearoyl-CoA desaturase (SCD) gene expression over 80% in both BSC and IPA. Conversely, palmitic and stearic acid increased SCD gene expression three fold in co-cultured in IPA, and stearic acid increased $AMPK{\alpha}$ gene expression in single- and co-cultured BSC and IPA. Consistent with our hypothesis, saturated fatty acids, especially stearic acid, promoted adipogenic and lipogenic gene expression, whereas unsaturated fatty acids decreased expression of those genes associated with fatty acid metabolism.