• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.219-224
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• 2011

In this study, we evaluated the anti-oxidative, whitening and anti-wrinkle effect of Tetrapanax papyriferum extract. Tetrapanax papyriferum was extracted by two different solvents which were n-Hexane, ethyl acetate. The anti-oxidant activity was measured by free radical scavenging activity using DPPH (1,1-diphenyl-2-picrylhydrazyl radical). And the inhibitory activities of tyrosinase for whitening effect and collagenase, elastase for anti-wrinkle were investigated. For anti-oxidant activity, ethyl acetate fraction of Tetrapanax papyriferum extract showed more significant activity than n-Hexane fraction of Tetrapanax papyriferum extract. For whitening activity, n-Hexane fraction of Tetrapanax papyriferum extract exhibited strong inhibition effects compared with reference. Therefore, Tetrapanax papyriferum extract may be useful as a new antioxidant and whitening agent.

• YAKHAK HOEJI
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• v.56 no.5
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• pp.320-325
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• 2012

To develop a new effective and safe natural antibiotics and antioxidant the essential oil was extracted from the roots of Anthriscus sylvestris by steam distillation. Its composition was analyzed by GC-MS. The activities of the essential oil fraction and its main components were evaluated against antibiotic-susceptible and -resistant strains of some food-born bacteria. In addition the synergism was examined with this oil combined with antibiotic by checkerboard titer test. The antioxidant activities were determined by in 1,1-diphenyl-2-picryl-hydrazil (DPPH) free radical scavenging activity test and reducing power assay. The essential oil fraction of A. sylvestris revealed significant inhibiting activities against antibiotic-susceptible and -resistant species of Vibrio and Shigella with MICs ranged from 1.00~4.00 mg/ml. It showed synergistic or additive effects when it was combined with amphicillin or trimethoprim/sulfamethoxazole (1 : 9). Additionally, the essential oil fraction of A. sylvestris exhibited significant DPPH free radical scavenging activity and the reducing power.

• Steel and Composite Structures
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• v.25 no.3
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• pp.315-326
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• 2017

In this work, thermoelastic dynamic behavior of functionally graded carbon nanotube reinforced composite (FG-CNTRC) cylinders subjected to mechanical pressure loads, uniform temperature environment or thermal gradient loads is investigated by a mesh-free method. The material properties and thermal stress wave propagation of the nanocomposite cylinders are derived after solving of the transient thermal equation and obtaining of the time history of temperature field of the cylinders. The nanocomposite cylinders are made of a polymer matrix and wavy single-walled carbon nanotubes (SWCNTs). The volume fraction of carbon nanotubes (CNTs) are assumed variable along the radial direction of the axisymmetric cylinder. Also, material properties of the polymer and CNT are assumed temperature-dependent and mechanical properties of the nanocomposite are estimated by a micro mechanical model in volume fraction form. In the mesh-free analysis, moving least squares shape functions are used to approximate temperature and displacement fields in the weak form of motion equation and transient thermal equation, respectively. Also, transformation method is used to impose their essential boundary conditions. Effects of waviness, volume fraction and distribution pattern of CNT, temperature of environment and direction of thermal gradient loads are investigated on the thermoelastic dynamic behavior of FG-CNTRC cylinders.

• Journal of Pharmaceutical Investigation
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• v.15 no.1
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• pp.1-7
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• 1985

Previous studies show that the free (unbound) fraction of disopyramide in human serum is drug concentration dependent~ at corresponding serum disopyramide concentrations that are achieved clinically. $^1^{\sim}^3^)\;Moreover$, disopyramide free fraction values vary several fold at any given drug concentration in human serum and tend to decrease as serum cocentrations of alpha-I-acid glycoprotein(AAG) incrase.$^4^)$ A recent $study^5^)$ demonstrates that the free fraction of disopyramide inhuman serum increases almost 2-fold following the addition of $14.4{\mu}M/L$ mono-N-dealkyldisopyramide. These studies and others. $^6^),\;^7^)$ prompted the present investigation to characterize the protein binding of disopyramide in human serum and solutions of AAG in the presence of mono-N-dealkyldisopyramide (a major metabolite of, disopyramide) and to determine the utility of using commercially available alpha-I-acid glycoprotein for drug protein binding displacement studies. Because many basic and acidic compounds are known to bind to alpha-I-acid $glycoprotein^8^)$ the present study. was performed to determine whteher commercially available AAG would provide a convenient protein source for such binding studies.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.36-40
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• 1995

Yam(Dioscorea) tubers were used as one of the dietary starches in Korea, China and Japan because of its characteristic properties. Yam tubers were powdered after freeze drying the sliced tubers to investigate carbohydrates. Chemical properties such as proximate components and carbohydrates were studied using three varieties of Korean yams, namely. D. batatas, D. aimadoimo and D. japonica. The proximate components of yam tubers showed that the major components of Korean yam tubers were carbohydrates and moisture. The main components of free sugars in yams were identified as fructose, glucose, sucrose and maltose. In addition to these four sugars, there were two unidentifiable peaks whose areas are too big to ignore. These results were obviously different from other reported data of free sugars in yams. The main components of total sugars were mannose and glucose.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.378-383
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• 1995

Phospholipid(PL), phosphatidylcholine(PC) and phosphatidylcholine free PL(PCF) were extracted from squid viscera and the antioxidant effects of each fraction on the oxidation of refined fish oil were evaluated. Polyunsaturated fatty acid contents were the highest in PC(46.7%) followed by PL(44.8%) and PCF(40.9%). The effects of each phospholipid fraction on stabilizing fish oil were compared by incubating at 40$^{\circ}C$ for 10 days. At the initial period(2 days), changes in peroxide value did not show any significant difference ; however, as incubation time was extended, PC fraction showed the strongest antioxidant activity. PL and PCF added to fish oils also resulted in increased stability against oxidation. Antioxidative effect of PC at the 5% level was equivalent to 0.05% BHT, 1% catechin and 1% tocopherol.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.625-629
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• 2011

To investigate the protective effect of eggplant (Solanum melongena L.) and its active compound, delphinidin, we used in vitro and cellular system. The active fraction from eggplant, BuOH fraction, showed protective effect from hydrogen peroxide-induced oxidative stress in WI-38 fibroblast cells. It suggests that eggplant would have the protective activity from radical-induced oxidative damage and its BuOH fraction would play the crucial role with antioxidative activity. In addition, delphinidin, the active compound from eggplant, exerted the strong 1,1-diphenyl-2-picrylhydrazyl scavenging effect with $IC_{50}$ value of 6.59 ${\mu}g/mL$. Furthermore, the cellular oxidative stress was induced by 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) in LLC-$PK_1$ cells, while treatment of delphinidin atteunated AAPH-induced oxidative stress as dose-dependent manner. The present study suggests the antioxidative activity of eggplant and delphinidin against free radical-induced oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.299-304
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• 1995

Antioxidative effect of tea extracts from green tea(steamed, roasted), oolong tea and black tea was investigated. Antioxidative activities of the crude catechin fraction were the most effective in oolong tea which contained the highest level of (-)-epigallocatechin gallate(EGCg). The water-soluble fraction obtained from oolong tea exhibited binding with more ferrous than copper ions. It showed a synergistic effect when used with an antioxidant such as BHT(0.5mg) and $\alpha$-tocopherol(2mg). Especially, this synergistic effect was exhibited more with BHT than with $\alpha$-tocopherol. Also steamed green tea, roasted green tea and oolong tea showed remarkable free radical scavenging action. The SC50(the concentration of a water-soluble fraction which is required to scavenge 50% of 100$\mu$M 1, 1-diphenyl-2-picryl hydrazyl radicals) of steamed and roasted green tea, oolong tea and black tea extracts were 11.3$\mu\textrm{g}$/ml, 11.4$\mu\textrm{g}$/ml, 12.7 $\mu\textrm{g}$/ml and 14.9$\mu\textrm{g}$/ml, respectively. It is assumed that the antioxidative activity of tea extracts is due to inhibition of peroxidation free radical scavenging and binding action of ferrous ions by mainly tea polyphenol compounds.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.18-22
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• 2013

To investigate radical scavenging effects and protective activities of bitter melon (Momordica charantia) against oxidative stress, in vitro and a cellular system using LLC-$PK_1$ renal epithelial cells were used in this study. The butanol (BuOH) fraction of bitter melon scavenged 63.4% and 87.1% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals at concentrations of 250 and $500{\mu}g/mL$, respectively. In addition, the BuOH fraction of bitter melon effectively scavenged hydroxyl radicals (${\cdot}OH$). At all concentrations tested, the scavenging activity of the BuOH fraction was more potent than that of the positive control, ascorbic acid. Furthermore, under the LLC-$PK_1$ cellular model, the cells showed a decline in viability and an increase in lipid peroxidation through oxidative stress induced by pyrogallol, a generator of superoxide anion ($O_2{^-}$). However, the BuOH fraction of bitter melon significantly and dose-dependently inhibited cytotoxicity. In addition, 3-morpholinosydnonimine (SIN-1), a generator of peroxynitrite ($ONOO^-$) formed by simultaneous releases of nitric oxide and $O_2{^-}$, caused cytotoxicity in the LLC-$PK_1$ cells while the BuOH fraction of bitter melon ameliorated oxidative damage induced by $ONOO^-$. These results indicate that BuOH fraction of bitter melon has protective activities against oxidative damage induced by free radicals.

• Archives of Pharmacal Research
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• v.15 no.3
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• pp.234-238
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• 1992

Using cell-free extract of Lysobacter lactamgenus, enzymatic conversion of $\delta$-L-($\alpha$-aminoadiphyl)-L-cysteinyl-D-valine (ACV) the first substrate of $\beta$-lactam biosynthesis, into antibiotic compounds was attempted. In high performance liquid chromatographic (HPLC) analysis, the biosynthetic intermediates for cephalosporin antibiotics including isopenicillin N, deacetoxycephalosporin C, deacetylcephalosporin C and unknown cephem compound were detected in reaction mixtures. It implies that cephabacin compounds from L lactamgenus could be produced by biosynthetic routes through penicillin ring formation and its expansion to cephalosporin ring, likely as cephalosporin C from Cephalosporium or cephamycin C from Streptomyces. Among biosynthetic enzyme in cell-free extract, the ring formation activity (isopenicillin N synthetase activity) was separated in 50-60% of ammonium sulfate fraction, and ring expansion activity (deacetoxycephalosporin C synthetase activity) was found to be in 40-50% fraction. The partially purified isopenicillin N synthetase could convert as much as 90% ACV to isopenicillin N during 6-hour reaction.