• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.107-110
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• 2006

Magnetite nanoparticles encapsulated with biodegradable polymer [poly(D,L-lactide-co-glycoiide), PLGA] were prepared by an emulsification-diffusion method. To investigate the effect of type of organic solvents on the mean particle sizes of obtained composite particles, different organic solvents [ethyl acetate (EA), propylene carbonate (PC) and acetone (ACE)] were used with a stabilizer [didodecyl dimethyl ammonium bromide (DMAB)]. The particle size of nanoparticles was observed by the dynamic light scattering method. When EA and PC as partially water-soluble solvents were used, small composite nanoparticles below 80nm were obtained, while large composite nanoparticles above 330nm were prepared for ACE as a fully water-soluble solvent.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.295-302
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• 2022

In this study, we investigated the anti-oxidant, anti-aging, and skin whitening effects of Korean mistletoe (Viscum album var. coloratum). The mistletoe fraction was composed of four types: hexane (HX), ethyl acetate (EA), butanol (BU), and methylene chloride (MC). In total phenol content assay, HX showed the highest phenol content among four fractions. In addition, EA significantly increased 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and catalase-like activities, and MC significantly increased superoxide dismutase (SOD)-like activity. When we compared IC₅₀ value in the hyaluronidase and elastase inhibition assay, MC had the lowest IC₅₀. In addition, we also performed tyrosinase inhibition assay to demonstrate the possibility of Korean mistletoe as a cosmetic component. HX showed the highest tyrosinase inhibition rate among the fractions.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.769-779
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• 2020

This study investigates the selective fractionation of lignin with uniform structures and lower molecular weight. Lignin solubilization was first performed using a solution of acetic acid (AA) and hydrogen peroxide (HP) (4:1, (v/v)) to form peracetic acid (PAA), which is a strong oxidant. After the PAA-induced solubilization that occurred at 80℃, totally soluble lignin was extracted by ethyl acetate (EA) and divided into organic- and water-soluble fractions. The EA fraction was then fractionated by open-column using three solutions (chloroform-ethyl acetate, methanol, and water) sequentially. With an increase in the solvent polarity during the fractionation step, the molecular weight of the lignin-derived compounds in the fraction increased. Remarkably, some lignin fractions did not have aromatic structures. These fractions were identified as carboxylic acid-containing polymers like poly-carboxylates. These results conclude that the selective production of lignin-derived polymers with specific molecular weight and structural characteristics could be possible through open-column fractionation.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.392-399
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• 2014

Haw(Crataegus pinnatifida Bunge) belongs to the rose family and has beneficial health effects such as anti-obesity and gastroprotective activities. This study compared the antioxidative activities of various solvent extracts from haw. After removing seeds, pulpy was extracted with 70% methanol, 70% ethanol, chloroform :methanol(CM, 2:1, v/v), n-butanol, and ethyl acetate(EA). Total phenol contents were 71.46, 70.41, 47.63, 47.49 and 45.95 mg/g in the 70% methanol, 70% ethanol, CM, n-butanol and EA extracts, respectively. Total flavonoid contents of CM and n-butanol extracts were higher compared to other extracts at 1.63 mg/g and 1.59 mg/g, respectively, whereas EA extract had the lowest flavonoid content at 1.12 mg/g. Corresponding to total phenol contents, among $NO_2$ radical scavenging activity, antioxidant activity by ${\beta}$-carotene bleaching assay, and superoxide dismutase(SOD)-like ability, 70% methanol and 70% ethanol extracts showed higher antioxidative activities than the other extracts. However, the lowest activities were n-butanol extract in $NO_2$ radical scavenging activity as well as EA extract in antioxidant activity by ${\beta}$-carotene bleaching assay and SOD-like ability. These results suggest that haw extracts are available as a new natural antioxidant, and its activities are attributed to antioxidant substances such as phenolic compounds and flavonoids.

• The Korea Journal of Herbology
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• v.27 no.4
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• pp.99-107
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• 2012

Objectives : The aim of this study was to authenticate whether fractionated extract of Rumex japonicus HOUTT. (RJ) has anti-inflammatory effects in mouse macrophage, RAW264.7 cells. Methods : Roots of RJ were extracted by methanol for 48hours. The methanol that gained was filtered and freeze dried. The methanol extract was dissolved in water and dichloromethane (DCM). After that, two layers were separated. Ethyl acetate (EA) added to the water layer and separated again. All the layers were filtered and freeze dried and the extracts were tested. Cytotoxic activity of extracts on RAW 264.7 cells was measured using MTS assay. The nitric oxide (NO) production was measured and proinflammatory cytokines and $PGE_2$ were measured by ELISA kit. The levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), I ${\kappa}$-B-${\alpha}$ and nuclear NF-${\kappa}B$ p65 expression were detected by western blot. Results : Our results indicated that DCM and EA extracts of RJ inhibited the LPS-induced NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 production in RAW 264.7 cells most effectively. DCM and EA extracts also had suppression effects of LPS-induced NF-${\kappa}B$ and MAPKs activation. Conclusions : This results demonstrate that fractionated extract of RJ has anti-inflammatory effects and among the fractioned extract, dichloromethane and ethyl acetate extract have best anti-inflammatory effects.

• Korean Journal of Pharmacognosy
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• v.22 no.3
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• pp.183-191
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• 1991

The effects of Ephedrae herba on cellular and humoral immune responses were investigated in mice. Group A and B of mice received intraperitoneal injection of methanol extracts, ether fraction(E), petroleum ether fraction(PE), ethyl acetate fraction(EA) and water fraction(W) for 5 days or 10 days before sensitization. The other group received i.p. injection of ephedrine (Ep) or pseudoephedrine $({\psi}\;Ep)$ for 1 day prior to sensitization. The change of body and spleen weights showed a tendency of decreasing but that of thymus showed increasing. Ear swelling was maximum at 48 hours after challenge and was significantly decreased in the groups treated with EA, W, Ep, and ${\psi}\;Ep$. HA titer was enhanced in EA, W and EP treated groups, HE titer being significantly decreased.

• Journal of Life Science
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• v.24 no.4
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• pp.386-392
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• 2014

Haw (Crataegus pinnatifida $B_{UNGE}$) is a medicinal plant commonly used in Korea due to its beneficial health effects. This study was performed to investigate the antioxidative activity of bioactive components from haw seed. Freeze-dried seed was processed with various solvents such as 70% methanol, 70% ethanol, a mixture of chloroform and methanol (2:1, v / v), n-butanol and ethyl acetate (EA). DPPH, reducing power, ferric reducing antioxidant power (FRAP), and ABTS radical scavenging activity decreased in this order: 70% methanol, 70% ethanol, EA, CM, n-butanol extracts. NO radical scavenging activity was high in the n-butanol extract (36.73% in 0.8 mg/ml concentration) and low in the 70% ethanol extract (24.96% in 0.8 mg/ml concentration). $OH^-$ radical scavenging activity of n-butanol extract (40.42% in 0.8 mg/ml concentration) was higher than the other extracts, but EA extract was the lowest (13.39%) at the same concentration. The results show that each extract contained various antioxidative substances and it seemed that different influence at each antioxidative activity.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.235-242
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• 2017

In this study, we evaluated the polyphenol content, flavonoid content, antioxidant and biological of 70% EtOH extract and its fractions (dichloromethane, ethyl acetate and water) of the plant Chrysanthemum indicum L. (CI) belonging to family chrysanthemum. antioxidant activity was determined 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and superoxide scavenging activity. The biological activity tests included measurement of ${\alpha}$-glucosidase and PTP1B. The results show that content of polyphenol and flavonoid in 70% EtOH of CI 30.20 mg and 31.58 mg, respectively. Among the different samples, ethyl acetate (EA) fraction showed the highest level of polyphenol (87.87 mg) and flavonoid (65.12 mg). The DPPH, ABTS and superoxide dismutase(SOD) antioxidant assay of EA fraction showed 93.84%, 93.38% and 84.68% inhibition respectively. The EA fraction also showed the highest antioxidant activity compared to 70% EtOH extract and other fractions. EA fraction ($20{\mu}g/mL$) showed the highest 30.29% and 99.24%, respectively compared to other samples. The results of this study show that the EA fraction contained more antioxidant and antidiabetic components than 70% EtOH extract and other fractions. In conclusion, we believe that CI may be useful natural antioxidant and functional material.

• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.255-260
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• 2016

Reactive oxygen species (ROS) has been played a critical role in damage of DNA. Recently, many effort is focusing to develop the natural antioxidants for controlling ROS. Zelkova serrata, Ulmaceae, is close as plants which are planted in front of Korea villages. Although Zelkova serrata is familiar with Koreans, those of antioxidant activities and protective effects on oxidative DNA damage haven't studied. We demonstrated antioxidant activities and inhibitory effects on oxidative DNA damage of Leaf from Zelkova serrata with ethyl acetate fractions (EA) and hot water extracts (HW). Between the extracts, EA showed higher activities in 1,1-diphenyl-2-picryl-hydrazyl, 2,2'-azino-bis[3-ethylbenzthiazoline-6-sulphonic acid radical scavenging, $Fe^{2+}$ chelating and reducing power than HW. Also, those of total phenolic content are 56.63 and 51.61 mg/g respectively. In addition, ${\phi}X$-174 RF I plasmid DNA cleavage assay for inhibitory effect by oxidative DNA damage was both EA and HW has significant protective effect on oxidative DNA damage. The results suggested that leaf from Zelkova serrata with ethyl acetate fractions and hot water extracts have surpassing potential as natural resources with antioxidant and inhibitory effect on oxidative DNA damage.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.163-172
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• 2017

The purpose of this study was to measure the bioactivity and antioxidant activity of peel from Gardenia jasminoides Ellis fructus (GJE). GJE have been known to contain functional materials such as crocin, crocetin, geniposide, gardenosid, geniposidic acid, iridoid glycosides etc. We were separated into GJE peel. After that, we determined proanthocyanidin. GJE peel were extracted by 70% methanol, ethyl acetate (EA) and distilled water (DW) of three solvents. To investigate by the solvent extract of flavonoid content and value as a functional food ingredient of GJE peel through antioxidant activities (DPPH radical scavenging activity, ABTS radical scavenging activity, superoxide dismutase like ability, hydroxyl radical scavenging activity, ferrous ion-chelating capacity) were performed. Solvent extract antioxidant activity of increasing concentrations (0.2, 0.4, 0.6 mg/mL) were significantly increased (p<0.05). GJE peel extracts showed lower activity than positive control (ascorbic acid, BHA, EDTA). These results, by a solvent of peel were found that the relationship with the increase of flavonoid content increased physiological activity. The antioxidant activity of the extract from the other except for the EA extract on peel was observed at a high level. The results suggest that GJE peel can be used as nutraceutical foods and natural antioxidant.