• Carbon letters
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• v.1 no.2
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• pp.82-86
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• 2000

The present research was undertaken to evaluate the possibility of water purification filter with activated carbon fibers (ACFs) using a very low cost precursor consisting of phenolic resin coated on glass fibers. The simplified procedure involving coating, curing and activation and a very low cost glass fiber as a raw material were adopted in order to reduce manufacturing cost. The breakthrough curves of the manufactured ACFs and the commercial activated carbon (AC, Calgon F-200) were investigated in the initial concentration range from 19 to 49 ppm for benzene, toluene and ethylbenzene. From breakthrough profiles, the manufactured ACFs had significantly faster adsorption kinetics than the AC. Especially the benzene breakthrough curves, the manufactured ACF (13 g of ACF with 32% of carbon on the glass) was over the limited level (5 ppb) after flowing of 32 l at initial concentration of 15 ppm, while the commercial AC was shown about 3 ppm in initial adsorption.

• Journal of Plant Biology
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• v.32 no.1
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• pp.41-49
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• 1989

Phenolic compounds such as gallic acid, ferulic acid, p-hydroxybenzoic acid, vanillic acid, salicylic acid, tannic acid, and hydroquinone were identified from the aqueous extracts and volatile substances of tomato plant by paper chromatography, high performance liquid chromatography and gas chromatography. The seed germination and seedling growth of the experimental species, lettuce and egg plant, were severely inhibited in 5$\times$10-3M of phenolic reagents identical to those identified from tomato plant. Germination and growth rate of test species in 5$\times$10-4M and 5$\times$10-5M were higher than that of 5$\times$10-3M. Therefore, 5$\times$10-3M of phenolic compounds would be assumed to be threshold concentration for allelopathic effects.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.599-603
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• 2001

The node of lotus rhizome (Nelumbo nucifera, Nymphaeaceae) have been used as a traditional medicine for the remedy of hemorrhage, blood stagnancy and thirstiness. To investigate phenolic compound from the node of Nelumbo nucifera, phytochemical isolation and structure elucidation were conducted. Four phenolic compounds were isolated from aqueous methanolic extract and the structure of these compounds were identised as (+)-catechin (1), (+)-gallocatechin (2), (+)-gallocatechin (4u-8)-catechin (3) and scolpoletin (4) respectively by the analysis of spectroscopic evidences and comparisions with the data of authentic samples.

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1183-1189
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• 2005

Although plant-derived phenolic acids have been reported to have anti-cancer activity, the exact mechanism is not completely understood. In this study, we investigated the role for reactive oxygen species (ROS) as a mediator of the apoptosis induced by caffeic acid (CA) and ferulic acid (FA), common phenolic acids in plants in HepG2 human hepatoma cells. CA and FA reduced cell viability, and induced apoptotic cell death in a dose-dependent manner. In addition, they evoked a dose-related elevation of intracellular ROS. Treatment with various inhibitors of NADPH oxidase (diphenylene iodonium, apocynin, neopterine) significantly blunted both the generation of ROS and the induction of apoptosis induced CA and FA. These results suggest that ROS generated through activation of NADPH oxidase may play an essential role in the apoptosis induced by CA and FA in HepG2 cells. These results further suggest that CA and FA may be valuable for the therapeutic management of human hepatomas.

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1127-1130
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• 2005

A new phenolic glucoside (1), pursargentoside, was isolated from the leaves of Prunus serrulata var. spontanea, along with three other known compounds, orobol 7-O-glucoside (2), $1{\beta}$, $2{\alpha}$, $3{\alpha}$, 24-tetrahydroxy-urs-12-en-28-oic acid (3), and chlorogenic acid (4). The structure of pursargentoside (1) was identified by spectroscopic data analysis including 1D and 2D NMR spectroscopy, as 2-O-${\beta}$-(6'-benzoyl)-glucopyranosyl o-(Z)-coumaric acid. Compounds 1, 2, and 4 exhibited ONOO- scavenging activity, whereas compound 3 was determined to be virtually inactive.

• Archives of Pharmacal Research
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• v.23 no.5
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• pp.455-458
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• 2000

The acetone extract of the roots of Rhodiola sachalinensis has furnished six phenolic compounds which exhibited significant scavenging effects against DPPH free radical. The structures of these compounds were identified and determined as gallic acid (1), (-)-epigallocatechin 3-O-gallate (2), kaempferol (3), kaempferol 7-O-$\alpha$ -L-rham nopyranoside (4), herbacetin 7-O-$\alpha$ -L-rhamnopyranoside, (5) and rhodiolinin (6) by physico-chemical and spectral evidences.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.1027-1029
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• 2011

Two new phenolic glycosides were isolated from the rhizomes of Curculigo orchioides Gaertn.. Based on comprehensive spectroscopic analyses including IR, MS, 1D- and 2D NMR (COSY, HSQC, and HMBC), their structures were elucidated as 3-hydroxyl-5-methyphenol-1-O-[${\beta}$-D-glucopyranosyl-($1{\rightarrow}3$)-${\beta}$-D-glucopyranoside (1) and 1',3'-dimethoxyl-4-hydroxyalangifolioside (2).

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1911-1916
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• 2004

The conformational preference of tetrahomodioxacalix[4]arenes with three different para substituents on the phenolic ring has been investigated by using ab initio molecular orbital theory (RHF/6-31$G^{\ast}$) and density functional theory (B3LYP/6-31$G^{\ast}$). The stability order is predicted to be cone > C-1,2-alternate > partial cone > 1,3-alternate > COC-1,2-alternate. The distorted cone conformation is found to be most stable in a gas phase and the calculated results are in agreement with the reported $^1$H NMR and X-ray experimental observations. The substitution of methylene with dimethyleneoxa bridges increases the size of the annulus of the molecule, its conformational mobility, and the number of hydrogen bonding patterns. The thermodynamic stability and the conformational characteristics of tetrahomodioxacalix[4]arenes are discussed in regards of the number of phenolic hydrogen bonding patterns and the polarity of a molecule. The substituent effects on the para position of the phenolic ring are also introduced.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.63-66
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• 2004

In this study, a hybrid composite journal bearing composed of carbon fiber reinforced phenolic composite liner and metal backing was manufactured to solve the seizure problem of metallic journal bearing materials because the carbon fiber has self-lubricating ability and the phenolic resin has thermal resistance characteristics. To estimate the wear resistance of carbon fiber phenolic composite, wear tests were performed at several pressures and velocities. The oil absorption characteristics, coefficient of thermal expansion, strength and stiffness of the composite were also tested. Using the measured stiffness values, the thermal residual stresses in the composite were calculated to check the reliability of the composite journal bearing.

• YAKHAK HOEJI
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• v.25 no.4
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• pp.199-204
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• 1981

The methanol extract of Thalictrum uchiyamai Nakai was fractionatedi nto four parts; (1) ether soluble nonphenolic fraction (2) phenolic tertiary bases fraction, (3) chloroform soluble tertiary bases fraction and (4) aqueous quaternary bases fraction. The fractions of this plant showed a total of twenty-four spots on the silica gel TLC. Ether soluble nonphenolic fraction and ether soluble phenolic fraction showed nine alkaloid spots respectively, chloroform soluble fraction showed three alkaloid spots and quaternary bases fraction showed three alkaloid spots. The antimicrobial activity of the four extracts was shown as follows; nonphenolic tertiary bases inhibited the growth of Micrococcus dutica at the concentration of $50\mu$g/ml, in phenolic tertiary bases $500\mu$g/ml concentration was inhibitory to Micrococcus dutica and to Staphyloccus aureus. In aqueous quaternary bases, $500\mu$g/ml concentration was inhibitory to Klebsiella pneumonae. Chloroform soluble tertiary fraction showed slight activity. All of bases showed reproducible activity against tested microorganisms.