• Journal of Nutrition and Health
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• 제15권1호
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• pp.30-38
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• 1982

Experiments were carried out in order to compare the natural antioxidants in the acetonitril extracts of raw and baked seeds of Korean sesame and perilla by thin layer and gas chromatography. The sample was dissolved in n-pentane and extracted with acetonitril and the acetonitril extract was separated by thin layer chromatography using silica gel. The spots were detected by spraying with 2, 6 -dichloroquinone -4-chlorimide, phosphomolybdic acid and dimethylamine as chromogenic reagents. Natural antioxidant, such as ${\delta}-tocopherol$ detected in raw and baked sesame and perilla seed oil by TLC and sesamol was detected only in raw and baked sesame seed oil by GC.

• 대한화학회지
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• 제56권5호
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• pp.591-596
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• 2012

Preparation of $AlPMo_{12}O_{40}$ (AlPMo) salts, supported on mesostructured SBA-15 silica, by the reaction deposition strategy causes the formation of isolated AlPMo nanocrystals inside the nanotubular channels. The remarkable characteristic of the SBA-15 structure is that all the cylindrical pores are connected by some small channels. This makes the whole pore system in SBA-15 three-dimensional. We have used 2D hexagonal SBA-15 silicas as hard templates for the nanofabrication of AlPMo salt nanocrystal. The oxidation of alcohols occurs effectively and selectively with $H_2O_2$ as the oxidant. AlPMo salt nanocrystal was used as the catalyst.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.384-388
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• 2010

Human microsomal prostaglandin E synthase-1 (mPGES-1) catalyzes the conversion of prostaglandin $H_2$ ($PGH_2$) into prostaglandin $E_2$ ($PGE_2$). To establish a stable and efficient method to assess the activity of mPGES-1, a coupled enzyme assay system using mPGES-1, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and phosphomolybdic acid (PMA) was developed. In this assay system, $PGH_2$ was converted to $PGE_2$ by mPGES-1, and then $PGE_2$ was further transformed to the 15-keto-$PGE_2$ by 15-PGDH accompanying the production of NADH, which was easily detected by fluorescence spectrometry in a multi-well plate format. During the reaction, spontaneous oxidation of $PGH_2$ was prevented by PMA. Using this novel assay, the $K_m$ value of mPGES-1 for $PGH_2$ and the $IC_{50}$ value of the previously characterized inhibitor, MK-886, were determined to be 0.150 mM and $2.8\;{\mu}M$, respectively, which were consistent with the previously reported values. In addition, low backgrounds were observed in the multi-wall plate screening of chemical compounds.

• Korean Chemical Engineering Research
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• 제44권2호
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• pp.187-192
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• 2006

폴리페닐렌 옥사이드(PPO)를 이용하여 헤테로폴리산(HPA)을 고정시킨 박막 제조를 통해 새로운 고분자 복합막을 제조하고 특성을 분석하였다. 헤테로폴리산인 텅스토인산(PWA)이나 몰리브도인산(PMA)을 혼합한 PPO 박막은 서로 같은 용매에 녹지 않으므로 혼합용매를 사용하여 제조하였다. 본 연구에서는 PWA를 녹이기 위한 용매로 메탄올을 PPO를 녹이기 위한 용매로 클로로포름을 사용하였으며, 혼합된 PPO-PWA 용액을 유리판 위에서 제막하였다. 다공성의 PPO-PWA 박막에 나피온 혼합물을 사용하여 복합막을 제조하였고, 제조된 복합막은 이온 전도도와 메탄올 투과도를 측정하여 특성화하였다. PPO-PWA 복합막의 형태와 구조는 SEM(scanning electron microscopy)과 EDS(energy dispersive spectrometer)로 관찰하였고, 복합막은 직접 메탄올 연료전지(DMFC)용 전해질로서의 성능을 시험하였다. PPO-PWA 구조를 가지고 있는 복합막을 이용함으로써 DMFC 내에서의 메탄올 투과 현상을 66％ 줄일 수 있었다.