• 한국식품위생안전성학회지
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• 제2권4호
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• pp.181-189
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• 1987

한국 토양균 중에서 esterase 저해제를 생산하는 균주인 Streptomyces strain DMC-498을 oatmeal yeast extract 배지에서 3일간 액내 배양하였을 때 최고의 저해작용을 나타내었으며 균사체의 메탄올 추출물로부터 저해제를 분리하였다. linoleic acid가 저해작용이 있음을 확인하였으며 50% 저해작용을 나타내는 linoleic acid의 양은 $0.045\;\mu\textrm{g}/ml$이었다. 활성이 보다 큰 compound A는 분자량이 500 이상이며 산소를 2개이상 함유하고 있는 환상구조의 지방족 화합물로 생각된다. 이것을 상경적 저해작용을 나타내었다. DMC-498 균주가 함유하는 지질의 주성분은 isostearic acid, isostearic acid methyl ester, linoleic acid methyl ester 및 oleic acid methyl ester이었다.

• 한국응용과학기술학회지
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• 제19권2호
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• pp.137-144
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• 2002

Methyl glycoside oleic acid polyester was successfully prepared from methyl glycosides and methyl oleate by emulsion interesterification in the presence of methyl fructoside oleic acid polyester as an emulsifier. Emulsion interesterification process was optimized to obtain 98% yield of methyl glycoside polyester within $3{\sim}5hr$ at temperatures as relatively low as $90{\sim}150^{\circ}C$ and $20{\sim}200mmHg$ pressure with a five-fold molar ratio of oleic acid methyl ester to methyl glycoside in the presence of 2(w/w)% potassium carbonate and 2O(v/v)% methyl fructoside polyester based on oleic acid methyl ester.

• ALGAE
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• 제31권1호
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• pp.61-72
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• 2016

Arctic microalgae thrive and support primary production in extremely cold environment. Three Arctic green microalgal strains collected from freshwater near Dasan Station in Ny-Alesund, Svalbard, Arctic, were analyzed to evaluate the optimal growth conditions and contents of fatty acids. The optimal growth temperature for KNF0022, KNF0024, and KNF0032 was between 4 and 8℃. Among the three microalgal strains, KNF0032 showed the maximal cell number of 1.6 × 107 cells mL^-1 at 4℃. The contents of fatty acids in microalgae biomass of KNF0022, KNF0024, and KNF0032 cultured for 75 days were 37.34, 73.25, and 144.35 mg g^-1 dry cell weight, respectively. The common fatty acid methyl esters (FAMEs) analyzed from Arctic green microalgae consisted of palmitic acid methyl ester (C16:0), 5,8,11-heptadecatrienoic acid methyl ester (C17:3), oleic acid methyl ester (C18:1), linoleic acid methyl ester (C18:2), and α-linolenic acid methyl ester (C18:3). KNF0022 had high levels of heptadecanoic acid methyl ester (26.58%) and heptadecatrienoic acid methyl ester (22.17% of the total FAMEs). In KNF0024 and KNF0032, more than 72.09% of the total FAMEs consisted of mono- and polyunsaturated fatty acids. Oleic acid methyl ester from KNF0032 was detected at a high level of 20.13% of the FAMEs. Arctic freshwater microalgae are able to increase the levels of polyunsaturated fatty acids under a wide range of growth temperatures and can also be used to produce valuable industrial materials.

• 식품보건융합연구
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• 제9권4호
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• pp.11-18
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• 2023

Oil was extracted from cashew nuts. The physicochemical parameters of the oil were determined. A chromatographic assay of the oil was carried out using Gas Chromatography-Mass Spectrometry. Seventeen compounds were detected: Phenol, Phenol 2-methyl-, Cyclohexene 4, 4-dimethyl-, m-Fluoro-2-diazoacetophenone 4-dimethyl-, Tetradecanoic acid, Phenol 4-octyl-, n-Hexadecanoic acid. Others are 9, 12-Octadecadienoic acid (Z, Z) - methyl ester, Hexadecanoic acid methyl ester, Methyl stearate, Dodecanoic acid methyl ester, 9, 12, 15-Octadecatrienoic acid methyl ester, 9, 12, 15-Octadecatrienoic acid (Z, Z, Z)-, Oleic acid, Octadecanoic acid, Tetracosanoic acid and 9-Octadecenoic acid methyl ester. Among the components are omega three and omega six essential free fatty acids. The rheological profiling and flow properties of cashew nut oil were determined using a Programmable Rheometer. Cashew nut oil exhibits slight dilatant behaviour at the low end of shear rate. The long chain and high molecular weight of its constituents controlled its rheology. Long-chained 9-Octadecenoic acid methyl ester, 9, 12-Octadecadienoic acid (Z, Z) - methyl ester, Tetracosanoic acid and methyl stearate, coupled with their high molecular weights are responsible for the shear thickening effect observed. Two models, Carreau-Yasuda and Ostwald-de Waele Power Law were employed to fit the rheological data. The Carreau-Yasuda model followed well the data.

• Tribology and Lubricants
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• 제35권2호
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• pp.132-138
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• 2019

In this study, we demonstrate the effects of the acidic properties of montmorillonite (MMT), which is commonly used as a catalyst, on the conversion and selectivity of the dimer acid methyl ester (DAME) synthesis. We synthesize DAME by the dimerization of conjugated linoleic acid methyl ester (CLAME) and oleic acid methyl ester using MMT KSF. Incidentally, trimer acid methyl ester was formed as a by-product during the DAME synthesis. There is a necessity to adequately adjust the strength and quantity of the acid site to control the selectivity of DAME. Therefore, we vary the pH of the MMT acid by using various metal hydroxides. The purpose of this study is to increase the yield of monocyclic dimer acid methyl ester, which is a substance with adequate physical properties for industrial applications (e.g., lubricant and adhesive, etc.), using a heterogeneous catalyst. We report the dimerization of fatty acid methyl ester by using base treated-KSF, and apply it to conjugated soybean oil methyl ester. Then, we transmute the acid site properties of KSF, such as pH of 5 wt.% slurry KSF and various alkali metals (Li, Na, K, Ca). Characterization of base treated-KSF using a pH meter, x-ray diffraction, inductively coupled plasma-atomic emission spectrometer, Brunauer-Emmett-Teller surface analysis, and temperature-programmed desorption. We conduct an analysis of CLAME and DAME using nuclear magnetic resonance spectroscopy, gas chromatography, and gel permeation chromatography. Through these experiments, we demonstrate the effects of the acidic properties of KSF on the conversion and selectivity of the DAME synthesis, and evaluate its industrial potential by application to waste vegetable oil.

• KSBB Journal
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• 제13권6호
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• pp.706-717
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• 1998

과당계열 배당체인 메틸프룩토시드를 반응출발문질로하여 과당계열 당 지방산 에스테르인 메틸프룩토시드 올레산 모노 및 디에스테르를 효소적 용매 및 무용매공정에 의하여 합성하였다. 용매공정으로부터 머틸프룩토시드 올레산 모노에스테르를 합성한 결과, 최적 상용용매로는 2-메틸-2-프로관올이 우수하게 나타났으며 매틸프룩토시드의 용해도는 $60^{\circ}C$애서 400g/L이상에 상당하였다. 최적반응조건을 검토한 결과, 에틸프룩토시드 올레산의 최적올비 3.1, 에틸프룩토시드의 최적 초기농도 200g/L, Novozym 435의 최적 촉매함량 1%(w!v), 반응온도 $60^{\circ}C$에서 반응시간 8시간만에 70%의 평 형 젠화율애 도달하였으며 12.6g/L-hr의 생산성으로 매렐프룩토시드 올레산 모노에스테프 블 생싼할 수 았었다. 그리고, 무용매공정에서 메틸프룩토시드 올레산 디에스터르를 합생한 결과, 메틸프룩토시드와 올레산의 최적돌에 l.2, Novozym 435의 최적 촉매함령, 10%(w/w), 반응온도 $70^{\circ}C$, 진공도 20 - 200mmHg 에서 반응시간 10시간만에 95%이상의 전화율로 140g;L-hr의 생산성으로 메틸프룩토시드 올레산 디에스테르를 생산할 수 있었다.

• 대한화학회지
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• 제35권1호
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• pp.85-89
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• 1991

한국 남해안 소흑산도에서 채집한 해면 V.japonica H.로부터 통상적인tetradecanoic 및 hexadecanoic methyl ester 이외에 탄소가 홀수인 pentadecanoic, heptadecanoic methyl ester와 가지달린 12-methyltetradecanoic, 14-methylpentadecanoic, 15-methylhexadecanoic 및 14-methylhexadecanoic methyl ester가 발견되었으며, 주 sterol 성분으로는 cholesterol과 소량의 ergost-25-ene-3,5,6-triol이 검출되었다. 한편, 여수 돌산도에서 채집한 해면 H.sinapium의 주 sterol성분은 5${\alpha}$-cholestan-3${\beta}$-ol이었고 cholesterol은 소량으로 얻어졌다. 지방산으로는 팔미틴산, 팔미토레인산, 올레인산, 스테아린산 및 리놀레인산 에틸에스터 이외에 상당량의 arachidonic산 에틸에스터가 함유되어 있었다. 상기 지역에서 채집한 또 다른 해면에서는 상당량의 tetradecanoic tetradecyl 및 hexadecyl ester와 sterol 성분으로 cholesteryl acetic 및 fatty acid ester가 함유되어 있었다.

• 공업화학
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• 제18권3호
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• pp.284-290
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• 2007

대두유로부터 생산된 바이오디젤과 바이오디젤 혼합 연료유를 대상으로 산화 특성과 지방산메틸에스터 함량 등 화학적 분석을 수행하여 자동차용 연료로서의 품질특성을 파악하였다. 대두유로부터 생산된 바이오디젤은 불포화 지방산인 oleic acid, linoleic acid 및 linolenic acid가 85 wt% 이상 함유되어 있었다. 특히 활성 메틸렌기를 함유한 다불포화 지방산인 linoleic acid와 linolenic acid가 60 wt% 이상 함유되어 있어 상대적으로 자동산화가 쉽게 일어나는 것으로 판단된다. 산화반응시 주요 반응물질은 linoleic acid와 linolenic acid였으며, 이들의 라디칼 자동산화에 의해서 비점이 약 $500^{\circ}C$ 전 후에 있는 탄소수 36 전 후의 고분자 물질이 형성되는 것을 확인하였다

• 한국식품과학회지
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• 제30권2호
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• pp.266-271
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• 1998

천연물로부터 안전성과 안정성이 우수한 항산화성 물질을 찾기 위하여 생약류 10종을 선정하여 95% ethanol으로 추출하면서 추출 수율과 팜유를 기질로한 항산화력을 비교한 결과 울금이 가장 좋은 것으로 나타났다. 이러한 울금 추출물을 팜유에 대해 첨가농도를 $0.05{\sim}0.5%$까지 높혀 가면서 현재 사용되는 천연 항산화제인 mixed tocopherol, rosemary 추출물들과 비교하여 항산화력을 측정한 결과 0.05%까지는 3종류 모두 유사한 항산화 효과를 나타내었으나 그 이상의 농도에 있어서는 울금 추출물의 항산화력이 월등히 우수하였다. 돈지에 대한 울금 추출물의 항산화 효과는 0.01% 첨가시 AI가 4.59로서 1.57인 팜유보다 월등하였으며, 대두유에 대해서는 첨가에 따른 항산화 효과가 전혀 나타나지 않았다. 각종 지방산 메틸에스테르에 울금 추출물을 각각 0.05%, 0.1% 첨가하였을 때 oleic acid methyl ester에 대해서는 AI가 각각 3.01, 4.33으로 크게 증가하였으나, linoleic acid methyl eser에 대해서는 각각 0.85, 0.96으로서 오히려 감소하는 경향이 나타났다.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2321-2324
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• 2013

An improved hybrid solar cell was obtained by focusing on the effects of ligand for CdSe nanoparticles, in the active layers. The performance was compared by mixing nanoparticles capped with pyridine or oleic acid for the acceptor material into poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester based active layer. The solar cells with pyridine capped CdSe nanoparticles showed a power conversion efficiency of 2.96% while oleic acid capped CdSe nanoparticles showed 2.85%, under AM 1.5G illumination. Formation of percolation pathways for carrier transport and a reduction in the hopping event resulted in better performance of pyridine capped nanoparticles.