• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1206-1212
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• 2010

This study was performed to establish optimum extraction condition of Tricholoma matsutake. A central composite design was applied to investigate the effects of independent variables, extraction temperature ($X_1$), extraction time ($X_2$) and water per sample ($X_3$) on dependent variables such as soluble solids contents ($Y_1$), total phenolics contents ($Y_2$), reducing sugar contents ($Y_3$), electron donating ability ($Y_4$) and nitrite scavenging ability ($Y_5$). The optimum extraction conditions were predicted and monitored by response surface methodology using SAS program based regression analysis. Soluble solids content, electron donating ability and nitrite scavenging ability were highly affected by water per sample. However, the contents of total phenolics and reducing sugar were affected by water per sample and extraction temperature as well. The optimum extraction conditions for soluble solids were 34.84 mL/g (water/sample) at $78.85^{\circ}C$, for 3.33 hr. In contrast, the optimum extraction conditions of electron donating ability were temperature of $91.00^{\circ}C$, time of 1.62 hr and water per sample of 39.42 mL/g. Taken together, the optimum ranges for hot water extraction of Tricholoma matsutake were $70{\sim}90^{\circ}C$, 2~4 hr and 30~50 mL/g.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.533-542
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• 2016

We investigate fluidization characteristics of the mixture of rice husk, silica sand and rice husk ash as a preliminary study for valuable utilization of rice husk ash obtained from gasification of rice husk in a fluidized bed reactor. As experiment valuables, the blending ratio of rice husk and sand (rice husk: sand) is selected as 5:95, 10:90, 20:80 and 30:70 on a volume base. Rice husk ash was added with 6 vol% of rice husk for each experiment and air velocity to the reactor was 0~0.63 m/s. In both rice husk/sand and rice husk/sand/ash mixture, the minimum fluidization velocity (Umf) is observed as 0.19~0.21 m/s at feeding of 0~10 vol.% of rice husk and 0.30 m/s at feeding of 20 vol.% of rice husk. With increasing the amount of rice husk up to 30 vol.%, $U_{mf}$ can not measure due to segregation behavior. The mixing index for each experiment is determined using mixing index equation proposed by Brereton and Grace. The mixing index of the mixture of rice husk/sand and rice husk/sand/ash was 0.8~1 and 0.88~1, respectively. The optimum fluidization condition was found for the good mixing and separation of rice husk ash.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.766-773
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• 2013

A transparent film was fabricated based on bacterial cellulose (BC), BC has excellent physical strength and stability at high temperature and it is an environmental friendly flexible material. In order to improve the conductivity, silver nanowire (AgNW) and/or graphene were introduced to the BC membrane. The aspect ratio of the AgNW synthesized in this study was 214, with a length of $15{\mu}m$ and width of 70 nm. The higher aspect ratio improved the conductivity by reducing the contact resistance. The thermal and electrical properties of 7 types of films prepared were investigated. Each film was fabricated with rectangular shape ($2mm{\times}2mm{\times}50{\mu}m$). The films were scored with a net shape by a knife, and filled with AgNW and graphene to bestow conductivity. The film filled with AgNW showed favorable electrical characteristics with a thickness of $350{\mu}m$, electron concentration of $1.53{\times}10^{19}$, electron mobility of $6.63{\times}10^5$, and resistivity of 0.28. The film filled with graphene had a thickness of $360{\mu}m$, electron concentration of $7.74{\times}10^{17}$, electron mobility of 0.17, and resistivity of 4.78. The transmittances at 550 nm were 98.1% and 80.9%, respectively. All the films were able to light LEDs bulbs although their brightness differed. A thermal stability test of the BC and PET films at $150{\pm}5^{\circ}C$ showed that the BC film was more stable, whereas the PET film was quickly banded. From these results, it was confirmed that there it is possible to fabricate new transparent conductivity films based on BC.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.135-144
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• 2013

The aim of this study was to evaluate various aspects of Vitex negundo L. leaf extract, such as the antioxidative activity, tyrosinase inhibitory effects, and inhibitory activities on ${\alpha}$-MSH induced melanogenesis, and active component analysis. The DPPH (1, 1-diphenyl-2-picrylhydrazyl) scavenging activities ($FSC_{50}$) of the ethyl acetate fraction and aglycone fraction of V. negundo L. leaf extract were $14.51{\mu}g/ml$ and $13.96{\mu}g/ml$, respectively. A luminol-dependent chemiluminescence assay revealed that the reactive oxygen species (ROS) scavenging activity ($OSC_{50}$) of the aglycone fraction of V. negundo L. leaf extract on ROS generated in an $Fe^{3+}$-$EDTA/H_2O_2$ system was the most prominent at $0.22{\mu}g/ml$. The protective effects of the extracts fractions of V. negundo L. leaf against the rose-bengal sensitized photohemolysis of human erythrocytes were increased in a concentration dependent manner ($1{\sim}50{\mu}g/ml$). In particular, there were greater protective effects of the aglycone fraction on the cellular membrane than that of the fat-soluble antioxidant (+)-${\alpha}$-tocopherol. The inhibitory effects ($IC_{50}$) on mushroom tyrosinase were the highest for the ethyl acetate fraction ($IC_{50}$ = $48.58{\mu}g/ml$). The inhibitory effect on ${\alpha}$-MSH induced melanogenesis in B16 melanoma cells was 41.80% at $50{\mu}g/ml$ of ethyl acetate fraction. Active component analyses by TLC, HPLC and LC/ESI-MS revealed luteolin and isoorientin. These results indicate that V. negundo L. leaf extract can be used as an antioxidant for ROS scavenging. Particularly, the luteolin and isoorientin of the ethyl acetate fraction may be applicable to new whitening cosmetics because of its inhibitory effect on mushroom tyrosinase and ${\alpha}$-MSH induced melanogenesis in B16 melanoma cells.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.275-276
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• 2009

민간단체들에 의하여 자율적으로 시작된 국내 유기농업은 친환경농업육성법(1997. 12.13)이 제정되면서 국가기관의 친환경농업 활성화 노력과 더불어 2008년 유기농재배 농가(8,460호)와 면적(12,033호)이 급격히 증가되었다. 또한 유기농업의 확산과 더불어 화학비료 및 유기합성 농약대체 친환경농자재들의 유통이 증가되고 있으나 관리규정이 없어 검증되지 않은 다양한 농자재들이 유통되어 친환경실천 농가들의 혼란이 초래되어 국정감사 시 문제점으로 지적과 함께 각계에서 관리제도의 필요성이 대두되었다. 친환경농업육성법 시행령 개정(대통령령 제19964호, 2007.3.27.공포, 2007.3.28.시행)으로 농촌진흥청에 친환경농자재심의회가 설치되어 효과와 효능을 검증하지 아니하고 친환경농산물 중 유기농산물 생을 해 사용가능한 자재인지 여부를 검토하여 그 결과를 공개하는 목록공시제가 마련되었다. 친환경유기농자재 목록공시는 1년에 4회 매분기말에 농촌진흥청 농자재관리과에서 접수를 받아 친환경농자재 분야별 전문위원회 검토 후 심의위원회 심의를 거쳐 접수일로부터 90일 이내에 농촌진흥청장이 공시(농진청 홈페이지, 관보게재)하고 친환경농업 관련기관 및 검토 신청자에게 통보함으로서 마무리된다. 목록 공시된 친환경유기농자재의 유효기간은 2년이다. 친환경농자재심의위원회는 토양개량 및 작물생육분야 전문위원회 위원 11명, 병 해충 관리분야 전문위원회 위원 11명 및 심의위원회 의원 20명으로 구성되어 있다. 2007년 3월부터 2009년 11월 30일 현재 목록 공시된 친환경유기농자재 제품은 (1) 양개량용 자재 25 개, (2) 작물생육용 자재 282개, (3) 토양개량 및 작물생육용 자재 308개, (4) 작물병해 관리용 자재 110개, (5) 작물충해 관리용 자재 : 224개, (6) 작물병해충 관리용 자재 5개 및 (7) 기타 자재 1개 제품으로 총 955개 제품에 이르고 있다. 한편, 공시연장 미신청, 현재 검토기준안에 필요로 하는 추가요청 자료 미제출 및 공시이외의 물질 사용으로 국내유통 중 단속되어 부적합한 판정을 받아 20여 제품이 목록공시가 취소되었다. 앞으로 목록 공시되는 친환경유기농자재는 제품의 주성분 함량 표기, 시용효과 검정방법 선, 제조방법 현장점검, 안전성 검정 등 여러가지 제도보완 및 사후관리 방안이 시급히 마련되어야 할 것으로 사려된다.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.595-604
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• 1992

Carbonate-type polyurethane resins containing anionic moieties were systhesized from NCO-terminated prepolymer method. Membranes were manufactured from the polymer solution and the separation of aqueous ethanol solution was investigated. To enhance the property of urethane resin, carbonate-type polyol(PTMCG) was used. ${\alpha}^{\prime},{\alpha}^{{\prime}{\prime}}$-dimethylolpropionic acid was used as a chain extender to increase the hydrophilicily of the urethane membrane. The ionization of the pendent carboxylic groups in urethane resin was carried out using trimthylamine. To confirm the formation of anionic groups in urethane resin, IR spectra of model compounds were compared with those of urethane resins. It was confirmed that the concentration of hard segment and hydrogen bond contributed to the property of the concentration of hard segment and hydrogen bond contributed to the property of urethane resin in which the mole ratio of chain extender and polyol was from 3:1 to urethane resin in which the mole ratio of chain extender and polyol was from 3:1 to 5:1. The carbonate-type polyurethane containing pendent carboxylic grop(PU) had Tg of around-$25^{\circ}C$ and Tm, $45^{\circ}C$ measured by DSC. Transition temperatures of one containing pendent anionic group(APU) prepared from the ionization of PU shifted to $8{\sim}10^{\circ}C$ lower temperature region than those of PU. Pervaporation membrane was prepared through the casting method. N, N-dimethylformamide (DMF) were used as a solvent and hexamethylene diisocyanate(HMDl) as a crosslinking agent. Swelling degree increased with ethanol concentration in mixure and the control of the swelling degree of the membrane could be achieved by crossliking. The results of pervaporation were as follows : separation factor, 2.3~9.8 ; flux, $27{\sim}79.5g/m^2hr$. Pervaporation separation capacity could be enhanced by reducing the molecular weight of polyol from 2,000 to 1,000.

• Research in Plant Disease
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• v.22 no.3
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• pp.145-151
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• 2016

Chemical fungicides have reduced Fusarium head blight (FHB) severity. However, by the effects of fungicide residues, they can only be used up to 30 days before time of harvest. Therefore, the development of new biofungicides that are applicable until harvest is required. In order to select plant extracts having antifungal activity against Fusarium graminearum for the control of FHB, we investigated the inhibitory effects of 225 medicinal plant extracts on spore germination of F. graminearum. Of these plant extracts, the methanol extract of Cirsium japonicum (CJ) roots showed the strongest antifungal activity. Through solvent partitioning, repeated column chromatography, and spore germination bioassay, two chemicals were purified and then their chemical structures were identified as ciryneol C (CC) and 1-heptadecene-11,13-diyne-8,9,10-triol (HD-ol) which are polyacetylene substances. Two active compounds effectively inhibited the germination of F. graminearum macroconidia; HD-ol ($IC_{50}$ of $3.17{\mu}g/ml$) showed stronger spore germination inhibitory activity than that of CC ($IC_{50}$ of $28.14{\mu}g/ml$). In addition, the wettable powder type formulation of ethyl acetate extract of CJ roots suppressed the development of FHB in dose-dependent manner, with control values of 78.92% and 31.56% at 250- and 500-fold dilutions, respectively. Combining these findings suggest that the crude extract of CJ roots containing polyacetylene compounds could be used as botanical fungicide for the control of FHB.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.149-159
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• 2008

Background: With increasing coronary bypass and peripheral vascular surgeries, the demand for homologous vascular or synthetic conduits has continued to grow, but wide-spread application has been limited by dismal patency rates. Although cryopreserved allograft valves may provide a suitable alternative, current viability or patency of implanted allograft vascular conduits has been unsatisfactory. Material and Method: We serially analyzed the outcomes of canine femoral artery and saphenous vein allograft implants after storage in either $4^{\circ}C\;or\;-170^{\circ}C$. Result: There were no differences in graft flow rate (patency) (p=0.264), rate of thrombosis (p=0.264), presence of endothelium (p=0.587), or immunohistochemical staining for thrombomodulin (p=0.657) were detected between grafts stored in $4^{\circ}C\;and\;-170^{\circ}C$. Greater flow occurred in the arterial grafts versus the venous grafts (p=0.030), irrespective of the preservation method, with a significantly lower incidence of thrombosis (p=0.030) in arterial allografts. There was a correlation coefficient of -0.654 between thrombosis and positive immunohistochemical staining for thrombomodulin (p=0.006) and a correlation coefficient of 0.520 (p=0.0049) between the endothelial presence and positive immunohistochemical staining for thrombomodulin. The relationship between the presence of endothelium and thrombomodulin expression failed to show any correlation within the first 2 weeks (p=0.306). However, a strong correlation was seen after 1 month (p=0.0008). Conclusion: Tissue storage in either $4^{\circ}C\;or\;-170^{\circ}C$ in 10% DMSO/RPMI-1640 preservation solution preserved grafts equally well. In terms of thrombosis and graft patency, arterial grafts were superior to venous grafts. Considering the poor correlation between thrombomodulin expression and the presence of an endothelium in the implanted graft within the first two weeks, grafts in this period would not be thromboresistant.

• Analytical Science and Technology
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• v.17 no.3
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• pp.199-210
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• 2004

A new polystyrene-divinylbenzene chelating resin containing 4,5-dihydroxy-naphthalene-2,7-disulfonic acid (chromotropic acid : CTA) as functional group has been synthesized and characterized. The sorption and desorption properties of this chelating resin for Cr(III) ion and Cr(VI) ion including nine metal bloodstain. As a results, FOB test kit could be effectively applied to identification of human blood at chelating resin was stable in acidic and alkaline solution. The Cr(VI) ion is selectively separated from Cr (III) ion at pH 2 and the maximum sorption capacity of Cr(VI) ion is 1.2 mmol/g. In the presence of anions such as $F^-$, $SO{_4}^{2-}$, $CN^-$, $CH_3COO^-$, $NO{_3}^-$, the sorption of Cr(VI) ion was reduced but anions such as $PO{_4}^{3-}$ and $Cl^-$ revealed no interference effect. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 2 was Cr(VI)>Sn(II)>Fe(III)>Cu(II)>Cd(II)${\simeq}Pb(II){\simeq}Cr(III){\simeq}Mn(II){\simeq}Ni(II){\simeq}Al(III)$. Desorption characteristics for Cr(VI) ion was investigated with desorption agents such as $HNO_3$, HCl, and $H_2SO_4$. It was found that the ion showed high desorption efficiency with 3 M HCl. As the result, the chelating resin, XAD-16-CTA was successfully applied to separation and preconcentration of Cr (VI) ion from several metal ions in metal finishing works.

• Journal of Dairy Science and Biotechnology
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• v.34 no.1
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• pp.21-35
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• 2016

Recently, there has been a rapid increase in the sale and purchase of an array of organic products. In particular, organic milk has grown in popularity. This growth could lead to expensive, premium retail prices for various organic cow's milk products. In fact, most consumers believe that (1) dairy farming to produce organic milk is beneficial for human health and (2) organic milk products are made without the use of various antibiotics, synthetic chemicals, genetic modification, extra hormones, and so on. Several factors, including breed, diet, and stage of lactation, are known to influence the composition of milk. Therefore, this review (1) presents a research outline to compare organic and conventional milk and (2) provides a summary of individual elements that affect the composition of milk.