• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.381-388
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• 2014

The antioxidant activities of extracts from Rubus coreanus Miquel (black raspberry) and Morus alba L. (mulberry) fruits were investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2-azino-bis-(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS) assay, and reducing power assay. Aqueous mixtures of ethanol, methanol, and acetone were analyzed in order to determine the most effective extraction solvent for the two fruits. Black raspberry and mulberry extracts with the 60:40 acetone-water mixtures (v/v) showed the highest DPPH radical scavenging activities (56.2 and 85.2%, respectively) compared to the other extraction solvents. The 60% acetone extract was finally selected as an extraction solvent and then sequentially fractionated according to solvent polarity. Among the fractions of the two fruits, the ethyl acetate fraction showed the highest antioxidant activity as well as total phenolic and total flavonoid contents. In addition, there were high correlation coefficients between antioxidant activities and their contents. The $EC_{50}$ value of the ethyl acetate fraction from mulberry fruit was 2.2 times lower than that of butylated hydroxytoluene (BHT) in DPPH assay. The major phenolic acid and anthocyanin of the two fruits were protocatechuic acid and cyanidin-3-glucoside, respectively.

• Analytical Science and Technology
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• v.18 no.3
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• pp.194-200
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• 2005

The N hyperfine coupling constants ($a_N$) of di-t-butyl nitroxide (DTBN) radicals in water-solvent system were measured with EPR spectroscopy. Various kinds of the solvents with different polarity such as acetone, dimethylsulfoxide (DMSO), methanol, ethanol and 1-propanol were applied and studied. Equilibrium constants for the solvation equilibrium and the solvent parameters ($E_T$, molar transition energy) of various water-solvent system were obtained from the experimental results and are presented. The $a_N$ values were plotted as a function of mole fraction of the solvent. In case of water-DMSO, water-ethanol and water-1-propanol system, slight negative deviations from the straight line were observed. In water-acetone system, the absorption wavelength (${\lambda}$) due to ${\eta}{\rightarrow}{\pi}^{\ast}$ transition increased linearly with the increase of mole fraction of acetone. The relationship between $a_N$ of DTBN and ${\lambda}$ due to ${\eta}{\rightarrow}{\pi}^{\ast}$ transition in water-acetone and water-DMSO system was examined. It was found that the electronic structure of the nitroxide radicals is stablized from the fact that the N hyperfine coupling constants of DTBN radicals are greatly unaffected in the environment of water-solvent system.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.690-695
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• 1994

The perilla seed and the germinated perilla seed $(25{\sim}28^{\circ}C$, $2{\sim}3\;days)$ were extracted by n-hexane, and from the extracted oil the antioxidative components were separated, and then the effect of the change in the contents of antioxidative components by germination on the oxidative stability of the perilla oil was studied. The perilla oils were solved acetone and methanol, and kept at $-60^{\circ}C$ overnight and separated into the frozen oil fraction and unfrozen solvent soluble fraction. By comparing the antioxidative stability of the frozen oil fraction the antioxidative components in the perilla oil were found to be methanol soluble. The methanol soluble fraction of perilla oil was applied to silica gel column chromatography and the separated fractions were compared in terms of antioxidative activity. The fraction of n-hexane : ethyl acetate (7 : 3, v/v) showing the highest antioxidative activity was further separated by TLC. The components included in the band $(R_f\;0.71)$ showing the highest antioxidative activity was separated by HPLC. Four peaks were observed on the HPLC chromatogram and the peak areas were changed by germination (perilla seed : peak 1; 46.5%, peak 2; 25.6%, peak 3; 22.6%, germinated perilla seed : peak 1; 43.8%, peak 2; 20.6%, peak 3; 29.8%). The comparative change in the contents of these components was considered to be one factor affecting the antioxidative stability of perilla oil by germination.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.317-326
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• 2017

The wood and bark of Hawthorn tree (Crataegus pinnatifida Bunge) were immersed with 70% aqueous acetone for 3 days. After filtering, the wood extracts were fractionated with n-hexane, chloroform ($CHCl_3$), n-butanol (n-BuOH) and $H_2O$, and the bark extracts were fractionated with n-hexane, $CHCl_3$, ethylacetate (EtOAc) and $H_2O$. Then antioxidative and anti-inflammatory activities were evaluated on each fraction. Antioxidative activity indicated high activity in the n-butanol soluble fraction of wood and in the EtOAc soluble fraction of bark. Especially, the EtOAc soluble fraction of bark showed much higher antioxidative value compared to the controls, buthylated hydroxytoluene (BHT) and ${\alpha}$-tocopherol. In the anti-inflammatory activity, all of the tested fractions except the $H_2O$ soluble fraction of wood showed high inhibitory effect on nitric oxide (NO) production. Based on the above results, the extracts of hawthorn tree may be applied for one of the natural biomass sources that can be used as an antioxidant and an anti-inflammatory substance.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.429-434
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• 2006

The dried needles (1.5 kg) of Picea abies Karsten were ground, extracted with acetone-$H_2O$ (7:3, v/v), concentrated, and fractionated with a series of n-hexane, methylene chloride, ethyl acetate and water on a separatory funnel. Each fraction was freeze dried, then a portion of ethyl acetate soluble powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-n-hexane mixture as eluents. The isolated compounds were identified by cellulose TLC, $^1H$-, $^{13}C$-NMR, FAB and EI-MS. (+)-catechin (compound I), (-)-epicatechin (compound II), kaempferol-3-O-${\beta}$-D-glucopyranoside (compound III), 4-hydroxyacetophenone (compound IV) were isolated from the ethyl acetate soluble fraction and (+)-catechin (compound I), protocatechuic acid (compound V) were isolated from the $H_2O$ soluble fraction of P. abies needle. The antioxidative activities of each fraction and the isolated compounds were tested by DPPH radical scavenging method, and EtOAc soluble fraction, (+)-catechin and (-)-epicatechin showed similar values to ${\alpha}$-tocopherol and BHT as controls.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.420-423
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• 2010

The proanthocyanidin fraction was isolated from the wild grape (Vitis amurensis) peel and its antioxidant capacities were examined to promote the utilization of wild grape by-products. The 70% acetone crude extract of the wild grape peel was fractionated with hexane, ethyl acetate, and water. The ethyl acetate fraction was applied to a Sephadex LH-20 column chromatograph, which was eluted with 50% methanol, 75% methanol, and 75% acetone. The proanthocyanidin characteristics and contents of the isolated fractions were investigated by the vanillin-$H_2SO_4$ and BuOH-HCl methods. Fraction 6 had the highest proanthocyanidin content ($49.35{\pm}2.75\;g%$) among the isolated fractions. The antioxidant activities of the proanthocyanidin fraction were examined by DPPH radical scavenging, FRAP assay, and total phenolic contents. The FRAP values and total phenolic contents of the fractions ranged from 3.54 to 32.25 mmol/kg and from 4.48 to 50.80 g/100 g, respectively. The proanthocyanidin contents was strongly correlated with DPPH radical scavenging activities, FRAP values, and total phenolic contents.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.254-258
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• 1997

To examine the characteristics of the antioxidative property of Buckwheat components, acetone extracts from a buckwheat, Suwon 5, was fractionated using five solvents. Hexane, ethylacetate, ether, butanol and water fractions were obtained. Butanol fraction showed the greatest electron donating ability and inhibitory effect on lipid peroxidation. It also showed the most excellent activity in the superoxide radical scavenging activity by xanthine/xanthine oxidase-cytochrome c reduction system. Spectrophotogram of butanol fraction was similar to that of rutin. Superoxide radical scavenging activity was related to the contents of rutin. Inhibitory effect of each fraction on xanthine oxidase was also measured. Butanol fraction had the strongest inhibitory effect on xanthine oxidase and $IC_{50}\;was\;3.1\;{\mu}g$. The inhibition type of butanol fraction on xanthine oxidase turned out to be a mixture of the uncompetitive and non-competitive modes.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.374.1-374.1
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• 2002

The barks o.f Pinus densiflara representative Pinus species graws in Korea, have been used for oriental traditional medicine as the remedies for rheumatitis. hemorrhage and cancer. Water soluble fraction of 80% acetone extracts from the barks af Pinus densiflera (PDB) showed nitrogen monoxide(NO) production inhibitory activity in IFN-${\gamma}$. LPS stimulated RAW 264.7 cell. (omitted)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1031-1038
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• 2012

Background: Turmeric ($Curcuma$ $longa$) has been shown to possess anti-inflammatory, antioxidant and antitumor properties. However, despite the progress in research with $C.$ $longa$, there is still a big lacuna in the information on the active principles and their molecular targets. More particularly very little is known about the role of cell cycle genes $p57^{kip2}$ and Rad9 during chemoprevention by turmeric and its derivatives especially in prostate cancer cell lines. Methods: Accordingly, in this study, we have examined the antitumor effect of several extracts of $C.$ $longa$ rhizomes by successive fractionation in clonogenic assays using highly metastatic PC-3M prostate cancer cell line. Results: A mixture of isopropyl alcohol: acetone: water: chloroform: and methanol extract of $C.$ $longa$ showed significant bioactivity. Further partition of this extract showed that bioactivity resides in the dichloromethane soluble fraction. Column chromatography of this fraction showed presence of biological activity only in ethyl acetate eluted fraction. HPLC, UV-Vis and Mass spectra studies showed presence three curcuminoids in this fraction besides few unidentified components. Conclusions: From these observations it was concluded that the ethyl acetate fraction showed not only inhibition of colony forming ability of PC-3M cells but also up-regulated cell cycle genes $p57^{kip2}$ and Rad9 and further reduced the migration and invasive ability of prostate cancer cells.

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.141-146
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• 2012

The outer bark of Prunus sargentii was collected, air-dried and extracted with 70% aqueous acetone. Then it was successively partitioned with n-hexane, dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc) and $H_2O$. From the EtOAc soluble fraction, four compounds were isolated by the repeated Sephadex LH-20 column chromatography. The isolated compounds were determined as (+)-catechin (1), (-)-epicatechin (2), taxifolin (3), and neosakuranin (4) by the spectroscopic analysis including $^1H$, $^{13}C$-NMR, and 2D-NMR spectrometers. The antioxidative activities on the isolated compounds and the separated fractions were evaluated by DPPH radical scavenging assay. The crude, EtOAc, and $H_2O$ soluble fractions indicated good antioxidative potential compared to the $CH_2Cl_2$ and n-hexane soluble fractions.