• Environmental Analysis Health and Toxicology
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• v.25 no.2
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• pp.145-151
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• 2010

Perfluorinated chemicals (PFCs) is a kinds of persistent organic pollutants, and have the potential toxicity of which is causing great concern. In this study, we employed Oryzias latipes embryos to investigate the developmental toxicity of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)s compound using flowthrow system for 14 day. O. latipes embryos were exposed to solvent control, 20, 40 and 80 mg/L of PFOS and 62.5, 130, 260 mg/L of PFOA respectively. After exposure, hatchability, mortality, total length and heart beats were examined. Hatching rates were reduced approximately 27% in the 80 mg/L PFOS-treated group and 17% in the 62.5, 130 mg/L PFOA-treated groups. Heart beats in the PFOS-treated groups were reduced at 7 day but, PFOA-treated groups were increased heart beats. 80 mg/L PFOS treated group showed significant reduction in growth (total length) level to 90% of control. But PFOA did not showed significant effect on growth. In the 14 days $LC_{50}$ of PFOS and PFOA was 22.74 mg/L and 173 mg/L, respectively. The overall results indicated that the early stage of O. latipes might be a reliable model for the testing of developmental toxicity to perfluorinated chemicals.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.5
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• pp.457-464
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• 2017

Etoricoxib features antioxidant and anti-inflammatory properties concomitantly, suggesting that it may be beneficial in testicular ischemia reperfusion (I/R) damage. Our aim is to investigate the effects of etoricoxib on testicular I/R damage induced with torsion-detorsion (TD). The etoricoxib + torsion-detorsion (ETD) groups of animals were given etoricoxib in 50 and 100 mg/kg of body weight (ETD-50 and ETD-100), while the testes torsion-detorsion (TTD) and sham operation rat group (SOG) animals were given single oral doses of distilled water as a solvent. TTD, ETD-50 and ETD-100 groups were subjected to $720^{\circ}$ degrees torsion for four hours, and detorsion for four hours. The SOG group was not subjected to this procedure. Biochemical, gene expression and histopathological analyses were carried out on the testicular tissues. The levels of malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta ($IL-1{\beta}$) and tumor necrosis factor alpha ($TNF-{\alpha}$) were significantly higher, and the levels of total glutathione (tGSH) and glutathione reductase (GSHRd) were significantly lower in the TTD group, compared to the ETD-50, ETD-100 and SOG groups. Etoricoxib at a dose of 100 mg/kg better prevented I/R damage than the 50 mg/kg dose. Etoricoxib may be useful in clinical practice in the reduction of I/R damage on testes caused by torsion-detorsion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.4024-4031
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• 2014

Nanofibers have attracted significant interest in many industrial fields because their high surface area and porosity. In addition, the continued use of petrochemical based polymers has caused the depletion of oil resources and accelerated the greenhouse effect by the emission of carbon dioxide. Therefore, biomass-based polymer has become a very important environmentally friendly alternative. In this study, nanofibers were fabricated by an electrospinning process using biomass based PEF(polyethylene furoate) prepared by the polymerization of 2,5-furandicaboxylic acid and ethylene glycol. Furthermore, the electrospun nanofiber was strongly affected by various parameters, such as the solvent, polymer concentration and electric field. In conclusion, nanofibers with an average fiber diameters of 200 - 700 nm could be prepared at polymer concentration of 15 wt% using HFIP, and their fiber diameter increased with increasing electric field.

• Journal of the Korean Applied Science and Technology
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• v.11 no.1
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• pp.7-16
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• 1994

Some seeds of the Rutaceae family, Zanthoxylum piperitum, Z. schinifolium officinalis, Poncirus trifoliata, Citrus unshin, were investigated to clarify their antioxidative components. Finely powdered samples were extracted by hexane, followed by dichioromethane and then 70% methanol in a hot bath. Its unsaponifiables containing X-and Y-tocopherol with trace amount of ${\beta}-and$\;{\delta}-tocopherol$. also showed comparatively weak activity, although the hexane fraction itself had no significant antioxidative effect on lard. Levels of total tocopherols in the samples averages 42. 24-154. 11 mg/lOOg total extractives. The dichloromethane-and 70% methanol extractives showed strong antioxidative activity, from which antioxidative substances were purified with benzene-acetone(6:5, V/V) on a silica gel column, and with a solvent mixture of acetonitrile-methanol-$H_2O$(40:40:20, V/V/V) on a Sep-Pak $C_{18}$ hydrolyzed by 5% KOH-ethanol. The recovered unsaponifiables were, then, separated on a column of high performance liquid chromatography. The unsaponifiables produced by hydrolysis of the isolates from dichloromethane extractives has epi-catechin(40.0-57.1%) and (+)-catechin<$l9.1{\sim}24.4%$ to total phenolic substances, on area base) as major component, accompanied by chlorogenic acid, gallic acid(?), trans-p-coumaric acid and tralls-p-ferulic acid including some unknown components, and those derived from 70% methanol extractives also comprise (+)-catechin($31.3{\sim}39.6%$ to total components, on area base), epi-catechin($2O.2{\sim}36.4%$), trans-p-cournaric acid(8.4-15.3%) and trans-p-ferulic acid($7.7{\sim}14.1%$) as predominant component with some minor coponents, but the fraction supposed to be gallic acid(?) is not present. The antioxidative activities of the phenolic components isolated in this work were in order of epi-catechin>catechin>chlorogenic acid>trans-p-ferluic acid>trans-p-coumaric acid.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.356-363
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• 2012

In this study we synthesis Hybrid resin(WPC) by milk casein and waterborne polyurethane(WPU). Then we experiment how casein effect to Hybrid resins in Full-Grain leather coatings. According to measured data for solvent resistance, WPU resin and Hybrid resins had good property. As test of tensile strength, WPU had most low strength(2.130 $kg_f/mm^2$) and WPC-3(WPU 91: casein resin 9) had most high strength(2.191 $kg_f/mm^2$). Also we knew that most good property of abrasion is WPC-3(50.090 mg.loss). In elongation case, WPU had most good result(637 %) in this experiment.

• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.374-379
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• 2016

When using an ionic liquid as co-solvent, the extraction efficiency of anticancer agent paclitaxel from biomass was dramatically improved. However, the residual ionic liquid had a significant negative effect on convenient and feasibility of following concentration and drying steps. In this study, a novel method was developed for the effective drying of the crude extract obtained from biomass extraction with ionic liquid. The residual ionic liquid was easily and conveniently removed by drying alone after pre-treatment and additional washing of a sample with water. The optimal crude extract/water ratio and mixing time for pre-treatment and crude extract/water ratio for additional washing were 1:70 (w/v), 4 min, and 1:100 (w/v), respectively. In the microwave-assisted drying process, the drying time was 9-fold shorter than in the vacuum oven drying process.

• YAKHAK HOEJI
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• v.52 no.1
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• pp.1-6
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• 2008

The present study investigated the antiproliferative effects of Crnum asiaticum var. japonicum against HL-60 human leukemia cells. The 80% MeOH extract or several solvent fractions from the C. asiaticum inhibited the growth of HL-60 cells, whereas the growth of HEL-299 cells, human embryonic lung fibroblast, was scarcely inhibited. When the HL-60 cells were treated with the $CHCl_3$ fraction, the BuOH fraction, the EtOAc fraction and the $H_2O$ fraction, DNA ladder, chromatin condensation and increase of sub-G1 hypodiploid cells were observed. Furthermore, the $CHCl_3$ fraction and the BuOH fraction reduced Bc1-2 mRNA level, whereas Bax mRNA level was increased. These results suggest that the inhibitory effect of C. asiaticum on the growth of the HL-60 cell might be mediated through the induction of apoptosis via the down-regulation of Bc1-2. Taken together, components of C. asiaticum might have a therapeutic potential for the treatment of human leukemia.

• Mycobiology
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• v.38 no.4
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• pp.295-301
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• 2010

We evaluated the antioxidant activity and tyrosinase inhibitory effects of Pleurotus ostreatus fruiting bodies extracted with acetone, methanol, and hot water. The antioxidant activities were tested against $\beta$-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, and ferrous chelating ability. Furthermore, phenolic acid and flavonoid contents were also analyzed. The methanol extract showed the strongest $\beta$-carotene-linoleic acid inhibition as compared to the other exracts. The acetone extract (8 mg/mL) showed a significantly high reducing power of 1.54 than the other extracts. The acetone extract was more effective than other extracts for scavenging on 1,1-diphenyl-2-picrylhydrazyl radicals. The strongest chelating effect (85.66%) was obtained from the acetone extract at 1.0 mg/mL. The antioxidant activities of the extracts from the P. ostreatus fruiting bodies increased with increasing concentration. A high performance liquid chromatography analysis detected seven phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, naringenin, hesperetin, formononetin, and biochanin-A in an acetonitrile and 0.1 N hydrochloric acid (5 : 1) solvent extract. The total phenolic compound concentration was $188{\mu}g$/g. Tyrosinase inhibition of the acetone, methanol, and hot water P. ostreatus extracts increased with increasing concentration. The results revealed that the methanol extract had good tyrosinase inhibitory ability, whereas the acetone and hot water extracts showed moderate activity at the concentrations tested. The results suggested that P. ostreatus may have potential as a natural antioxidant.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.222-230
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• 2012

We evaluated the inhibitory effects of extracts and components of Geranium thunbergii on aldose reductase (AR) and galactitol formation in rat lenses with high levels of galactose as a part of our ongoing search of natural sources for therapeutic and preventive agents for diabetic complications. The inhibitory effects of water, methanol and ethanol extracts of G. thunbergii on rat lens AR (RLAR) were determined. Comparing inhibitory effects of various solvent extracts, ethanol extract showed RLAR inhibitory activity ($IC_{50}$ values, 5.24 and $6.39{\mu}g/m{\ell}$, respectively). The ethanol extract was fractionated to chloroform, ethyl acetate and water. Of these, the ethyl acetate fraction from ethanol extract of G. thunbergii exhibited RLAR inhibitory activity ($IC_{50}$ value, $2.64{\mu}g/m{\ell}$). In order to identify the bioactive components of ethyl acetate soluble fraction of ethanol extract from G. thunbergii, eight compounds, namely gallic acid (1), protocatechuic acid (2), p-hydroxybenzoic acid (3), brevifolin carboxylic acid (4), geraniin (5), ellagic acid (6), kaempferol-3-O-arabinofuranosyl-7-O-rhamnopyranoside (7), kaempferitrin (8) were isolated. The isolates were subjected to in vitro bioassays to evaluate their inhibitory activity on RLAR and galactitol formation in rat lenses. The ellagic tannins (5, 6) and flavonoid (7) exhibited strong inhibitory effects on RLAR. Also, these three compounds (5, 6 and 7) suppressed galactitol accumulation in rat lens under high galactose conditions, demonstrating the potential to prevent galactitol accumulation exo vivo. These results suggest that the extracts and components of G. thunbergii are a promising agent in the prevention or treatment of diabetic complications.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.4
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• pp.154-159
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• 2001

(Li,Al)$MnO_2(OH)_2$:Co compound was synthesized by hydrothermal method. $MnO_2$, LiOH.$H_2$O, $Co_3O_4$ and $Al(OH)_3$ were used as starting materials and the optimum conditions for synthesis of monolithic (Li,Al)$MnO_2(OH)_2$:Co compound were as follows : reaction temperature; $200^{\circ}C$, reaction time; 3 days, hydrothermal solvent; 3M-KOH solution, reaction apparatus; seesaw type, atomic ratio of Li:Al:Mn;Co = 1:2.1:2.5~2:0.5~1. Monolithic(Li,Al)$MnO_2(HO)_2$:Co compound synthesized in this work had a god crystallinity and excellent color forming effect as a blue pigment compatible with natural mineral. The particles of the synthesized (Li,Al)$MnO_2(OH)_2$:Co compound have hexagonal plate shape with the size of 0.5~1 $\mu\textrm{m}$.