• Food Science and Biotechnology
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• v.17 no.1
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• pp.1-7
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• 2008

Soybeans with brown, black, and yellow seed coats were compared to total phenolic contents and antioxidant activities including 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals. Also, 3 seed coats were examined for inhibitory activities on tyrosinase and lipoxygenase-1 on the basis of spectrophotometric and polarographic methods. Among seed coat extracts, 80% methanol extract of brown soybean seed coat showed the highest total phenolic contents ($68.9{\pm}3.29\;mg$ GAE/g) as well as exhibited potent scavenging effects on the DPPH ($IC_{50}=4.3\;{\mu}g/mL$) and ABTS ($IC_{50}=3.7\;{\mu}g/mL$) radicals. In a polarographic experiment, this extract was potentially inhibited the oxidation of L-tyrosine and L-3,4-dihydroxy-phenylalanin (L-DOPA) catalyzed by mushroom tyrosinase with $IC_{50}$ values of 12.4 and $63.7\;{\mu}g/mL$, respectively. It was also detected inhibition of the tyrosinase catalyzed oxidation of L-DOPA with an $IC_{50}$ value of 120.3 mg/mL in UV spectrophotometric experiment. In addition, this extract inhibited the linoleic acid peroxidation catalyzed by lipoxygenase-1 with an $IC_{50}$ value of $4.0\;{\mu}g/mL$. These results suggest that brown soybean may possess more beneficial effect on human health than black and yellow soybeans.

• Journal of the Korean Vacuum Society
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• v.16 no.2
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• pp.99-104
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• 2007

Porous silicon exhibiting dual optical properties, both $Febry-P{\acute{e}}rot$ fringe (optical reflectivity) and photoluminescence had been developed and used as chemical sensors. Porous silicon samples were prepared by an electrochemical etch of p-type silicon wafer (boron-doped, <100> orientation, resistivity ; $1-10{\Omega}cm$). Two different types of porous silicon, fresh porous silicon (Si-H terminated) and oxidized porous silicon (Si-OH terminated)by the thermal oxidation, were prepared. Then the samples were exposed to the vapor of various organics, such as methanol, acetone, hexane, and toluene. Both reflectivity and photoluminescence were simultaneously measured under the exposure of organic vapors for sensing VOC's. These surface-modified samples showed unique respond in both reflectivity and photoluminescence with various organic vapors. While polar molecules exhibit greater quenching photoluminescence, molecules having higher vapor pressure show greater red shift for reflectivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.2
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• pp.146-151
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• 1987

The storage stability of sardine oil and the effect of BHA on the oxidation of fatty acids especially, highly unsatureted fatty acids like EPA and DHA were investigated. The sardine oil was extracted from round sardine, with chloroform-methanol(2:1 v/v) solvent with/without addition of BHA, and then stored at $30^{\circ}C$. The deterioration of oil was examined periodically by measuring acid value(AV), peroxide value(POV), carbonyl value(COV), and oxygen absorption. The changes in fatty acid composition during the storage was determined by GLC analysis to elucidate the oxidative stability of individual fatty acid. Formation of free fatty acid increased rapidly according to the storage time elapsed in the BHA free oil while it was obviously inhibited in the BHA added oil. Peroxides and carbonyl compounds were formed very rapidly at the beginning of storage of BHA free oil. But in the oil extracted with BHA, formation of peroxides was somewhat inhibited and formation of carbonyl compounds was very strongly inhibited. Principal fatty acids of sardine oil were $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5}\;and\;C_{22:6}$ acids, and $\omega_33$ polyunsaturated fatty acid $(\omega_3\;PUFA)$ content was very high as much as $23\%$ of the total fatty acid content. The oxidative degradation of fatty acids was enhanced at PUFA especially $C_{20:5}$ ana $C_{22:6}$ acid in BHA free oil. However, the oxidation was fairly retarded in the oil extracted with BHA and the both $C_{20:5}$ and $C_{22:6}$ acids remained at the end of a month storage.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.63-66
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• 2011

The bark of Machilus thunbergii was extracted with 80% aqueous methanol (MeOH), and the concentrated extract was partitioned using ethyl acetate (EtOAc), butanol (n-BuOH), and $H_2O$, successively. From the EtOAc fraction, five lignans were isolated through the repeated silica gel, octadecyl silica gel (ODS) and, Sephadex LH-20 column chromatography. Based on nuclear magnetic resonance (NMR), mass spectroscopy (MS), and infrared spectroscopy (IR) spectroscopic data, the chemical structures of the compounds were determined to be machilin A (1), machilin F (2), licarin A (3), nectandrin A (4), and nectandrin B, (5). This study presents comparative account of five lignans from M. thunbergii bark contributing inhibition of low density lipoprotein (LDL), ACAT-1, and ACAT-2. Compounds 2-5 showed varied degree of antioxidant activity on LDL with $IC_{50}$ values of 2.1, 11.8, 15.3, and $4.1{\mu}M$. Compounds 1, 2, and 3 showed inhibition activity on ACAT-1 with values $63.4{\pm}6.9%$ ($IC_{50}=66.8{\mu}M$), $53.7{\pm}0.9%$ ($IC_{50}=109.2{\mu}M$), and $78.7{\pm}0.2%$ ($IC_{50}=40.6{\mu}M$), respectively, at a concentration of 50 mg/mL, and on ACAT-2 with values $47.3{\pm}1.5%$ ($IC_{50}=149.7{\mu}M$), $39.2{\pm}0.2%$ ($IC_{50}=165.2{\mu}M$), and $52.1{\pm}1.0%$ ($IC_{50}=131.0{\mu}M$, respectively, at a concentration of 50 mg/mL.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.433-441
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• 2013

In this study, the anti-oxidative, anti-inflammatory, anti-melanogenic activities of Endlicheria anomala (Nees) Mez methanol extract (EAME) were evaluated by use of in vitro assays and cell culture model systems. The results revealed that EAME scavenges various radicals such as 1,1-diphenyl-2-picryl hydrazyl hydrogen peroxide induced reactive oxygen species, and lipopolysaccharide induced nitric oxide. Furthermore, EAME induced the expression of anti-oxidative enzymes such as heme oxygenase 1, thioredoxin reductase 1, NAD(P)H dehydrogenase 1, and their upstream transcription factor, nuclear factor-E2-related factor 2. Moreover, EAME inhibited in vitro DOPA oxidation and 3-isobutyl-1-methylxanthine induced melanogenesis in B16F10 cells. Its anti-melanogenic activity will have originated from the inhibition of tyrosinase enzyme activity and melanogenesis related protein expression. Taken together, these results provide the important new insight that E. anomala possesses various biological activities such as anti-oxidative, anti-inflammatory, and anti-melanogenic. Therefore, it might be utilized as a promising material in the fields of nutraceuticals and cosmetics.

• Journal of Life Science
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• v.30 no.2
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• pp.169-177
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• 2020

For this study, we prepared organic solvent fractions from methanol extracts of Houttuynia cordata and Lespedeza cuneate, and analyzed their chemical components and various biological functions such as anti-oxidation, angiotensin-converting enzyme (ACE) inhibition, and α-glucosidase inhibitory activities. We found that DPPH radical scavenging activity was highest in the ethyl acetate fractions of Houttuynia cordata (90.8%) and Lespedeza cuneata (91.2%), whereas ABTS radical scavenging activity was highest in the ethyl acetate fractions of Houttuynia cordata (86.1%) and the chloroform fractions of Lespedeza cuneata (95.6%). FRAP activity was highest in the ethyl acetate fraction of Houttuynia cordata (360.1 mg TE/g) and Lespedeza cuneata (239.2 mg TE/g). ACE inhibitory activity was highest in the chloroform fraction of Houttuynia cordata (13.2%) and Lespedeza cuneata (35.2%). And, α-glucosidase inhibitory activity was highest in the ethyl acetate fraction of Houttuynia cordata (56.3%), and the water residue of Lespedeza cuneata (93.6%). Finally, we investigated the DPPH radical scavenging activity of 20 types of pure compounds identified in Houttuynia cordata and Lespedeza cuneate. The results show that quercetin demonstrates the highest DPPH radical scavenging activity. Overall, these results help us to understand the functional chemical components of Houttuynia cordata and Lespedeza cuneate and the biological effects of these components.

• Applied Chemistry for Engineering
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• v.2 no.2
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• pp.127-137
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• 1991

The dissociation and partial oxidation of $CH_3OH$ on polycrystalline $MoO_3$ powder catalyst were studied using thermal desorption spectrometry(TDS) under high vacuum condition. $CH_3OH$ was dissociatively adsorbed on $MoO_3$ in the forms of surface methoxy($-OCH_3$) and atomic hydrogen(-H). $CH_3OH$ desorbed at 425 K via the re-association of methoxy and adsorbed hydrogen atom, and HCHO desorbed at 545 K through the bond breakage of C-H in methoxy. Water TDS spectra showed two desorption peaks, that is, ${\alpha}$-peak at 428 K and ${\beta}$-peak at 586 K. It was suggested that ${\alpha}$-peak was due to the hydroxyl formed on $MoO_3$ surface during the dissociation of $CH_3OH$, and that ${\beta}$-peak was from the association of lattice oxygen and surface hydrogen atom formed by the bond breakage of C-H in methoxy. Pre-adsorbed oxygen on the surface of $MoO_3$ catalyst increased the amount of adsorption of $CH_3OH$ by promoting the dissociation of $CH_3OH$ on the surface, whereas pre-adsorbed water decreased the amount of adsorption of $CH_3OH$ by blocking of adsorption sites for $CH_3OH$.

• Food Science and Preservation
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• v.20 no.3
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• pp.342-347
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• 2013

In recent years, polyphenol-rich herbs, fruits and processed foods, which are made of plant origin, have attracted much attention due to their potential health benefits. Pomegranate (Punica granatum L.) is an important source of bioactive compounds and has been used to treat diseases because of its medicinal properties. This research was focused on characterizing Korea's national cultivar and a similar product from California, USA. To evaluate their bioactive compounds and pharmacological activities, their anti-oxidation and cancer inhibition properties, as well as their organic acid and free sugar contents, were investigated. The national cultivar had low total sugar and high organic acid contents, contrary to the imported product. The results showed that the peel of national cultivar had high polyphenol and ellagic acid contents compared to imported product. The free radical scavenging capacity was evaluated via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and its positive correlation with the total polyphenol contents was found. The anti-cancer activity of methanol extracts revealed growth inhibition against the prostate cancer cell. These results signify that while pomegranate, national cultivar, is more sour than the imported product, its health benefits could be excellent. Also, the polyphenol compound content of the non-edible part (such as the peel and the seed) was higher than that of the juice. Thus, it is suggested that the byproduct of the juice extraction could be potentially used in other fields such as medicine or dietary agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.769-777
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• 2004

A Helicobacter pylori urease inhibitor from Rubus coreanus Miquel has been isolated and partially characterized for aiming to Prevent H. pylori growth and decrease harmful accumulation of ammonia in human gastric mucosa. We screened urease inhibitory activities in 519 extracts library prepared by solvent extraction from 173 kinds of edible plants, medicinal herbs, herbs and seaweeds using a colorimetric urease assay system. As results of primary and secondary screening, 70% acetone extract of Rubus coreanus Miquel was selected as potent candidate, showing about 24% inhibitory activity. The acetone extract was sequentially partitioned into RCE/RCWI and RCB/RCW2 layers with ethyl acetate and butanol. The major active component in RCW2, water layer from butanol fractionation was revealed to be peptidic or proteinous substance by inhibitory activity determination after pronase digestion and periodate oxidation. RCW2-IIIc a was isolated by sequential column chromatography on DEAE-Toyopearl 650C, Butrl-Toyopearl 650M and Sephadex LH-20. The isolated urease inhibitor RCW2-IIIc $\alpha$, was highly pure proteinous substance with molecular weight of 13kDa by high-performance gel permeation liquid chromatography. RCW2-IIIc$\alpha$ has about 5 times higher inhibitory activity than 70％ acetone extract, showing high stability against heat treatment and peptic digestion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.8
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• pp.1241-1247
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• 2015

The objective of this study was to determine antioxidant properties of polyphenol fractions of cranberry powder employing lipopolysaccharides (LPS)-stimulated RAW264.7 macrophage cells. Ethyl acetate fraction (EF) and methanol fraction (MF) of cranberry powder were prepared using a C18 Sep-Pak cartridge. When cells were treated with LPS for 20 h, intracellular reactive oxygen species (ROS) and DNA damage significantly increased. In cells pre-treated with EF, MF, and total fraction (TF: combining EF and MF), significant reductions of intracellular ROS were observed. The tested fractions reduced LPS-induced DNA damage measured by Hoechst staining. In addition, LPS-induced DNA oxidation was attenuated when cells were pre-treated with TF and MF. However, there was no significant difference in LPS-induced superoxide dismutase activity.