• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.152-159
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• 2019

To characterize new physiologically active components in Korean apple vinegar, a crude polysaccharide (KAV-0) was prepared by precipitation with 80% (v/v) ethanol. KAV-0 mainly comprises 38.2% mannose, 19.1% galactose and 14.3% glucose. In an in vitro cytotoxicity analysis, KAV-0 promoted the proliferation of peritoneal macrophages and RAW 264.7 cells in a dose-dependent manner, and showed no cytotoxicity in B16-BL6 melanoma cells. Murine peritoneal macrophages and RAW 264.7 cells stimulated by KAV-0 produced various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factor $(TNF)-{\alpha}$, and nitric oxide (NO). Intravenous (i.v.) administration of KAV-0 significantly augmented NK cell cytotoxicity against Yac-1 tumor cells. In experimental lung metastasis caused by B16-BL6 melanomas, prophylactic i.v. administration of KAV-0 at a dosage of $1,000{\mu}g/mouse$ inhibited lung metastasis by 53.0%. These results suggest that the crude polysaccharide (KAV-0) isolated from Korean apple vinegar has a considerably high anti-metastatic activity and immunomodulatory activities beneficial to human health.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.653-659
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• 2018

In this study, we investigated the antioxidant activities and anti-aging efficacy in terms of suppression of matrix metalloproteinases (MMPs) in UVB-irradiated HaCaT cells by adding the ethanol extracts of Josaengheogchal (JE) and Shintoheug rice (SRE). In the electron-donating ability and ABTS radical-scavenging assays, we observed that both JE and SRE had scavenging activities and in a collagenase inhibition assay, both extracts showed inhibition effects of over 73% at $1,000{\mu}g/mL$ concentration. The expression of MMP-1 and -3, when the extracts were treated with UVB $50mJ/cm^2$, irradiated human HaCaT keratinocytes, was analyzed by western blotting and reverse-transcription polymerase chain reaction (RT-PCR). The results showed that MMP-1 and -3 proteins and mRNAs were downregulated in a concentration-dependent manner in response to both extracts. Therefore, we expect that these compounds have a potential for the use as functional ingredients with anti-aging effects in the cosmetic and food industries.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.88.1-88.1
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• 2011

SOFC는 사용되는 셀의 디자인에 따라 튜브형, 평판형으로 구분되어진다. 평판형의 경우에는 전해질 지지형(ESC), Anode 지지형(ASC) 및 금속 지지형(MSC)로 크게 나눌 수 있다. SOFC 스택은 이와 같은 셀과 밀봉재, 집전체, 분리판의 구성요소를 여러 장으로 적층하여 이루어진다. SOFC 발전시스템은 SOFC 스택과 EBOP, MBOP로 구성되는데, SOFC 발전시스템의 상용화를 위해 선행되어야 할 것은 스택의 안정적 출력 및 신뢰성 확보이다. 즉, 셀, 밀봉재, 분리판 및 집전체로 대변되는 구성요소들이 스택에 장착되었을 때 그 기능을 최대한 발휘하면서도 점진적 또는 급격한 품질저하가 발생되지 말아야 한다. 특히, 밀봉재의 경우 SOFC에 사용되는 연료와 공기의 혼합(Cross-over)을 방지하는 중요한 기능을 담당하고 있으며 여러 장 적층된 분리판의 전기적 단락을 방지해야 한다. 또한 SOFC의 특성상 $700^{\circ}C$ 이상의 고온에서 다른 구성요소와 화학적 반응이 없어야하고 열싸이클(Thermal cycle)을 견딜 수 있도록 충분한 기계적 강도가 보장되어야 하는 등 요구되는 품질기준이 엄격하다. SOFC의 밀봉재는 접합형(Brazing), 압착형(Compressive), 용융-고정형(Glass-ceramic)이 대표적으로 적용되고 있다. 이 중에서 Brazing 물질과 방법은 현재 활발히 연구가 수행 중에 있지만 범용적으로 사용되고 있지는 않은 상태이고 Compressive 밀봉재와 Glass-ceramic 밀봉재가 대면적 SOFC 스택에 사용되어 적용 가능성을 평가받고 있다. 본 연구에서는 SOFC 구성요소의 국산화를 추진하는 지경부과제의 결과물 중 (주)써모텍에서 개발한 Glass-ceramic 밀봉재(RC1) 단품에 대한 특성평가와 실제 단전지 평가를 통해 SOFC 스택 적용 가능성을 평가하였다. 밀봉재 단품에 대한 특성평가는 용융특성, 상분석, 열팽창계수 등의 물리적, 화학적 평가 외에 가스 누설 정도를 평가하는 기밀도 평가와 SOFC의 작동 온도인 $700^{\circ}C$와 상온 분위기를 주기적으로 인가하는 Thermal cycle 특성을 평가하였다. 셀을 한 장 사용하는 단전지(Unit cell) 평가는 RIST에서 자체 제작한 $100{\times}100mm^2$ 평판형 ASC 셀을 사용하여 수행하였으며, 밀봉재는 Dispensing 공정을 통해 구성되었다.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.322-329
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• 2018

A diarylheptanoid, (5S)-1,7-bis-(3,4-dihydroxyphenyl)-5-hydroxyheptane-3-one-5-O-${\beta}$-D-xylopyranoside, named oregonin (1), was isolated from the of Alnus japonica (A. japonica), which is a species of the genus Betulaceae, growing throughout Korea, Japan and China. The structure was elucidated by various spectroscopic methods including negative and positive LC/MS, 1H-NMR, and 13C-NMR techniques or by comparison with authentic samples. In order to evaluate the anti-oxidative activities of oregonin (1) isolated from A. japonica, 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity and 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulphonic acid] (ABTS) radical scavenging activity were measured in vitro. Oregonin from A. japonica exhibited potent DPPH and ABTS radical scavenging activities. A. japonica shows not only 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity and ABTS radical scavenging activity, but also apoptosis modulative effects. The present results indicate that A. japonica could be a hair-growth-promoting agent for cosmetic products.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.439-443
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• 2016

In this report, $MnO_2$ nanoparticle-deposited functionalized graphene sheets were prepared and their superior electrochemical performances were demonstrated by cyclic voltammetry, galvanostatic charge-discharge, and impedance analysis. Ionic liquids were employed to functionalize the surface of reduced graphene oxides (RGOs), leading to prevention of the aggregation of RGO sheets and abundant growth sites for deposition of $MnO_2$ nanoparticles. As-prepared $MnO_2/RGO$ nanocomposites were characterized using scanning electron microscope, transition electron microscope, X-ray photoelectron spectroscopy, and X-ray diffraction. Electrochemical properties of $MnO_2/RGO$ electrode were evaluated using $Na_2SO_4$ electrolyte under a three-electrode system. The $MnO_2/RGO$ electrode showed a high specific capacitance (251 F/g), a high rate capability (80.5% retention), and long-term stability (93.6% retention).

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.82-82
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• 2003

오디는 옛부터 보혈자음(補血滋陰), 생진윤조(生津閏操), 현훈이명(眩最耳鳴), 심계실면(心悸失眠), 수발조백(鬚髮早白) 등을 치료하는 효능을 가진다고 알려져 있다. 상심자(桑 子)라 하여 뽕나무 열매로서 한방에서 상심(桑 ), 상실(桑實), 오심(烏 ), 흑심(黑 ) 등으로 지칭되며, 뽕나무과(Moraceae)에 속하는 뽕나무(Morus alba L)의 성숙한 과실로 취화과(聚花果)에 속하며 작은 수과(瘦果)가 많이 모여 이루어진 장원형으로 길이 1 내지 2 cm, 지름 0.5 내지 0.8 cm이며 황갈색, 갈홍색 또는 암자색을 띠고 짧은 줄기가 있다. 작은 수과(瘦果)는 난원형으로 조금 납작한 편이며, 길이는 약 2 mm, 너비는 약 1 mm 이고 육질의 화편(花片) 4개가 둘러싸고 있다. 그러나 아직까지는 오디에 대하여 자연과학적인 연구방법을 이용하여 구체적으로 연구된 바가 많지 않다. 또한 이의 생리활성 성분에 대해서도 그 작용과 연관지어 보고된 바가 많지 않다. 뇌졸중 가운데 뇌조직으로 가는 혈액 공급의 감소 혹은 차단으로 발생되는 허혈성 뇌졸중(ischemic stroke)은 전체 뇌졸중 환자의 약 80%정도를 차지하고 있으나 아직까지 뇌신경세포 손상기전의 복잡성 등으로 뇌졸중으로 발생하는 뇌신경세포의 손상을 보호해 줄 수 있는 물질이 개발되어 있지 못한 실정이다. 한편, 천연물로부터 뇌허혈 보호작용을 가지는 물질의 도출은 주로 한방에서 처방을 중심으로 이루어지고 있으며, 따라서 처방으로부터 신경보호작용을 가지는 물질의 도출은 그 처방에 함유되어 있는 각종 생약이 갖는 다양한 활성으로 인해 어려운 점이 있으며, 비록 효과가 있다고 하더라도 과학적인 입증자료가 매우 미비한 실정이다. 이에 본 연구에서는 위에 언급된 자료를 토대로 오디추출물이 뇌허혈에 효과가 있을 것이라는 가정하에 in vitro system을 이용하여 오디추출물의 신경보호작용기전을 검색하고자 DPPH radical 의 생성억제효과, PC12 cell line을 이용한 산화적 스트레스에 의한 오디추출물의 방어효과, LSP에 의하여 활성화된 BV-2 cell에 미치는 영향 등을 검색하였다. 오디의 DPPH 소거활성은 단일화랍물인 bacicalein과 유사한 효과를 나타냈으며 PC12 cell line을 이용한 산화적 스트레스에 의한 오디의 방어 효과는 LDH activity를 행한 결과 농도 의존적으로 LDH 유리 량을 감소시켰다. 뇌손상시에 오디추출물의 염증방어 효과를 관찰하기 위하여 microglial cell line인 BV2 세포주를 선택하여 배양한 후 LPS로 자극을 준 후 일차적인 염증지표인 NO양을 측정한 결과 BV2 cell에 LPS 100 ng/ml을 처리하는 경우 nitrite량이 유의적으로 증가하였는데 이때 오디추출물을 1, 5, 10 ug/ml의 용량으로 처리하는 경우 역시 저농도에서 NO생성량을 감소시켰다. 정리해보면 뽕나무과 식물인 오디는 신경보호효과가 있는 것으로 사료되는데 이러한 효과는 아마도 오디의 항산화효과에 기인한 것으로 추정된다.

• Membrane Journal
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• v.30 no.3
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• pp.158-172
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• 2020

In the aspect of saving energy and water, facilitating the separation membrane for the water treatment has been rising recently as one of the possible solutions. However, microbial biofouling effect is the biggest obstacle that hinders reaching higher permeability over a prolonged period of nanofiltration operation. To solve this problem and fully utilize the filtration membranes with enhanced performance, largely two kinds of solutions are studied and the first and the most commonly mentioned type is the one using the silver nanoparticles. Since silver nanoparticles are important to be well tailored on membrane surface, various methods have been applied and suggested. Using silver nanoparticles however also has the drawbacks or possible toxicity risks, raising the need for other types of utilizing non silver particles to functionalize the membrane, such as copper, graphene or zinc oxides, and amine moieties. Each attempt included in either kind has produced some notable results in killing, preventing, or repelling the bacteria while at the same time, left some unsolved points to be evaluated. In this review, the effects of metal nanoparticles and other materials on the antifouling properties of water treatment membranes are summarized.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.619-627
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• 2021

Cocoa bean husk is an important by-product of the cocoa industry. This study was conducted to measure the changes in the quality characteristics of sausage with added cacao bean husk powder (0, 0.25, 0.5, 1, 1.5, and 2%; ascorbic acid 0.2%) at 4℃ for 15 days. The total polyphenol, total flavonoid, DPPH, and ABTS⁺ radical scavenging activity of sausages increased with the addition of cocoa bean husk powder (p<0.001). As the amount of added cocoa bean husk powder increased, quality deterioration characteristics such as pH increase, redness discoloration, lipid oxidation, protein degradation, and texture change during storage were decreased (p<0.05). In particular, 1% sausage was shown to inhibit TBARS and VBN, similar to ascorbic acid-added sausage. In terms of sensory characteristics, the 0.5 and 1% sausages received the highest score for overall preference. Therefore, we concluded that addition of 1% cocoa bean husks to sausages improved their storage characteristics and palatability.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.543-548
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• 2018

The current study examined antioxidant and neuronal cell protective effects of the crude polysaccharide fraction in Cudrania tricuspidata fruits (CTP). The radical scavenging activities of (1,1-diphenyl-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) and reducing power and FRAP of CTP were increased dose-dependently. In addition, the expression of neuroprotective effect of CTP was tested in HT22 mouse hippocampal cells. CTP treatment exhibited non cytotoxicity at dose levels below $500{\mu}g/mL$. Within this optimal concentration range, CTP treatment significantly increased cell viability in $H_2O_2-treated$ HT22 cells. Furthermore, CTP treatment increased superoxide dismutase (SOD) activity and decreased malonaldehyde (MDA) levels in HT22 cells. Therefore, these results indicate that the crude polysaccharide fraction from Cudrania tricuspidata fruits (CTP) possesses antioxidant activities and displays therapeutic potential as a useful source material in the development of brain disorder treatments targeting oxidative stress in neuronal cells.

• Food Science and Preservation
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• v.17 no.2
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• pp.267-274
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• 2010

To obtain basic information on the potential use of Camellia japonica leaf as a raw material in functional food, leaf antioxidant and anticancer activities were investigated. The radical-scavenging activity of various solvent fractions from the leaf, as shown by the DPPH radical test, increased in a dose-dependent manner, with the water fraction showing the highest activity. The reducing power of various solvent fractions from the leaf was also dose-dependent, and, again, the water fraction showed the highest reducing power. The water fraction showed strong antioxidant activity in the linoleic acid test and was also capable of scavenging nitrite in a dose-dependent manner. Proportions of 92.15% and 95.61% of available nitrite were scavenged by the water and butanol fractions, respectively, at levels of $1,000{\mu}g/mL$. Both butanol and water fractions exhibited strong inhibitory effects on the growth of human lung and colon cancer cells. The total phenolic contents of the butanol and water fractions were 216.26 mg/g and 220.68 mg/g, respectively. High-performance liquid chromatography (HPLC) showed that quercetin and epicatechin were the predominant phenolic compounds in the water fraction. The activities of this fraction are attributable to the presence of these phenolic compounds, particularly quercetin and epicatechin.