• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.361-364
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• 1999

The binding characteristics of Anagrapha falcifera nuclear polyhedrosis virus (AtNPV) to Spodoptera frugiperda 21 (Sf21) cells were investigated. The cells displayed an affinity of 4.7×10/sup 10/M/sup -1/ with about 3,300 binding sites per cell. The biochemical nature of the AfNPV-binding sites on the cell surface was also partially identified. Our findings suggest that the binding-site moiety has a glycoprotein component, but that the direct involvement of oligosacccharides containing N-acetylglucosamine or sialic acid residues in binding is unlikely, and that AfNPV entry into Sf21 cells may be via receptor-mediated endocytosis.

• 한국초등과학교육학회지:초등과학교육
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• 제18권2호
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• pp.1-19
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• 1999

Based on the analysis of commonalities and differences in the views of science achievement in major reform documents in the United States and Korea, an aggregated view of science achievement is presented in this paper Science achievement is conceived of in terms of science content and science process. The components of science content include: (a) concepts and theories I n physical, life, and earth and space science;(b) science, mathematics, and technology;(c) science in personal and social perspectives;(d)history and nature of science;and (e) unifying themes. The components of science process include: (a) scientific understanding;(b) scientific investigation;(c) scientific communication; and (d) scientific habits of mind. The components of science process.cut across and intersect with the components of science content. The components of science achievement overlap and are related to one another. Despite such an overlap, understanding the rot e that each component plays provides insight into its unique contributions as well as its interactions with other components. A definition of science achievement and identification of its components based on major reform documents provides a guideline for science assessment as well a s science teaching and learning.

• Natural Product Sciences
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• 제4권2호
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• pp.105-114
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• 1998

The antimutagenic activity of a methanol extract of Ecklonia stolonifera (Laminariaceae) against aflatoxin $B_1\;(AFB_1)$ was demonstrated with the Salmonella typhimurium assay. The numbers of revertants per plate decreased significantly when this extract was added to the assay system using S. Salmonella typhimurium TA100. The methanol extract also exhibited significant inhibitory effects on the micronuclei formation in mouse peripheral blood reticulocytes and the DNA damage in mouse spleen lymphocytes induced by N-methyl-N-nitrosourea (MMU) and benzo(a)pyrene (B(a)P). The MeOH extract was then sequentially partitioned with $CH_2Cl_2,\;CH_2Cl_2$ insoluble intermediate, EtOAc, n-BuOH, and $H_2O$. All fractions possessed antimutagenic activity but the $H_2O$ fraction was inactive. Among active fractions, the EtOAc and $CH_2Cl_2$ insoluble intermediate fractions showed the highest activity. Column chromatography using $SiO_2$ and Sephadex LH-20 yielded phloroglucinol from the EtOAc fraction. Phloroglucinol also demonstrated significant antimutagenic activity, and inhibitory effects on the micronuclei formation in mouse peripheral blood reticulocytes and DNA damage in mouse spleen lymphocytes induced by MMU and B(a)P.

• 한국수산과학회지
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• 제51권6호
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• pp.640-646
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• 2018

To determine whether there are differences in the food component characteristics of the cultured recessive small-sized abalone Haliotis discus hannai (SA; 30-40 each/kg) and middle-sized abalone (MA; 10-15 each/kg), the proximate compositions, fatty acid and total amino acid compositions of these two species were evaluated. Additionally, extraction methods were performed on the SA to asses the quality characteristics of the resulting. In terms of proximate composition, MA had lower moisture and carbohydrate levels and higher crude protein contents than SA. The total amino acid contents of MA and SA were 15,734.4 and 11,379.1 mg/100 g, respectively, the major amino acids were glutamic acid, aspartic acid, serine, glycine, alanine, leucine, arginine and lysine, and the major fatty acids were 16:0, 18:0, 18:1n-9, 18:1n-7, 20:4n-6, 20:5n-3, and 22:5n-3. The pH levels and total nitrogen and amino nitrogen contents of the hot-water extract (WE) and scrap enzyme hydrolysate (SE) samples from the SA were 6.32 and 6.05, 1.36% and 1.52%, and 342.1 and 403.1 mg/100 g, respectively. The extraction yields and free amino acid contents from SA were 1,317 and 440 mL/kg, and 8,721.1 and 9,070.7 mg/100 g, respectively, and the concentrations of major components were as follows: arginine, glycine, glutamic acid, alanine and lysine. Additionally, the complex extract (WE+SE) was superior to the traditional extract (WE) in terms of extraction yield, amino-nitrogen content, and organoleptic qualities but not odor.

• 한국식품영양과학회지
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• 제38권1호
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• pp.70-75
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• 2009

연어 가공 부산물인 연어 가슴지느러미 부근 근육의 식품성분 특성에 대하여 살펴보았고, 아울러 연어 fillet 근육과 비교 검토하였다. 연어 가슴지느러미 근육의 일반성분은 수분함량이 64.4%, 조단백질 함량이 17.2%, 조지방 함량이 16.2%, 조회분 함량이 1.4%이었고, pH 및 휘발성염기질소 함량은 각각 6.73 및 7.8 mg/100 g이었으며, fillet 처리 근육을 기준으로 한 수율은 7.4%이었다. 연어 가슴지느러미 부근 근육의 TCA 가용성 질소 함량은 479 mg/100 g으로, fillet 근육의 612 mg/100 g에 비하여 낮았고, 명도, 적색도, 황색도 및 색차는 각각 54.86, 22.08, 22.41 및 52.35로, fillet 근육에 비하여 차이가 없었다. 연어 가슴지느러미 부근 근육의 아미노산 총 함량은 17.1 g/100 g이었고, 주요 아미노산은 aspartic acid, glutamic acid, leucine 및 lysine 등이었으며, 주요 구성 지방산은 16:0, 18:1n-9 및 18:2n-6, 20:5n-3 및 22:6n-3 등으로, fillet 근육의 그것과 차이가 없었다. 연어 가슴지느러미 근육의 칼슘과 인의 함량은 각각 19.1 mg/100g 및 211.7 mg/100 g이었다. 이상의 결과로 미루어 보아 연어 가슴지느러미 부근 근육은 수산가공품 재자원으로 이용 가능하리라 판단되었다.

• 한국식품저장유통학회지
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• 제17권1호
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• pp.139-144
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• 2010

난대성 상록활엽수종의 자원화 및 식품 소재화 탐색을 목적으로 구실잣밤나무(Castanopsis cuspidata var. sieboldii $N_{AKAI}$) 열매(구실잣밤) 추출물의 수율, pH, 당도, 색도, 구성당, 유기산 함량, 페놀 함량 및 항산화활성을 검정하였다. 각 용매에 대한 추출물의 수율은 물 추출물에서 3.6%로 가장 높았고, pH는 6.43의 중성값을 보였으며, 당도는 3.17 $^{\circ}Brix$를 나타내었다. 색도 중 L값은 83.07, a값은 1.49 그리고 b값은 10.48을 나타내었다. 구성당의 조성 및 함량은 fructose 27.11 mg%, glucose 26.29 mg%, galactose 0.86 mg%로 나타났다. 유기산은 총 5종이 동정되었으며, oxalic acid(59.44%), formic acid (23.99%), malic acid (11.24%), citric acid (3.34%), succinic acid (1.99%) 순으로 나타났다. 총 페놀 함량은 물 추출물에서 27.69 mg% 수준으로 가장 높았고, DPPH radical-scavenging 활성은 대조구인 $\alpha$-tocopherol ($SC_{50}\;12.47{\mu}g/mL$)에 비해 낮은 수준이었으나 EtOAc 추출물($SC_{50}\;74.88{\mu}g/mL$)에서 가장 강한 활성을 보였다. 이와 같은 결과를 바탕으로 구실잣밤은 다양한 식품소재 및 기능성 소재로서의 활용성이 기대되었으며, 또 도토리의 대용 및 병용이 가능한 소재로서 실용화 가능성이 확인되었다.

• 한국작물학회지
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• 제47권5호
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• pp.390-394
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• 2002

Spikelet number per unit area(SPN) is a major determinant of rice yield. Nitrogen nutrition status and biomass during reproductive stage determine the SPN. To formulate a model for estimating SPN, the 93 field experiment data collected from widely different regions with different japonica varieties in Korea and Japan were analyzed for the upper boundary lines of SPN responses to nitrogen nutrition index(NNI), shoot dry weight and shoot nitrogen content at panicle initiation and heading stage. The boundary lines of SPN showed asymptotic responses to all the above parameters(X) and were well fitted to the exponential function of $f(X)=alphacdot{1-etacdotexp(gamma;cdot;X)}$. Excluding the constant, from the boundary line equation, the values of the equation range from 0 to 1 and represent the indices of parameters expressing the degree of influence on SPN. In addition to those indices, the index of shoot dry weight increase during reproductive stage was calculated by directly dividing the shoot dry weight increase by the maximum value ($800 extrm{g/m}^{-2}$) of dry weight increase as it showed linear relationship with SPN. Four indices selected by forward stepwise regression at the stay level of 0.05 were those for NNI ($I_{NNI}_P$) at panicle initiation, NNI($I_{NNI}_h$) and shoot dry weight($I_{DW}_h$) at heading stage, and dry weight increase($I_{DW}$) between those two stages. The following model was obtained: SPN=48683ㆍ $I_{DWH}$$^{0.482}$ㆍ $I_{NNIp}$$^{0.387}$ㆍ $I_{NNIH}$$^{0.318}$ㆍ $I_{DW}$ $^{0.35}$). This model accounted for about 89% of the variation of spikelet number. In conclusion this model could be used for estimating the spikelet number of japonica rice with some confidence in widely different regions and thus, integrated into a rice growth model as a component model for spikelet number estimation.n.n.

• 식물조직배양학회지
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• 제27권5호
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• pp.407-409
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• 2000

Outer envelope membrane proteins of chloroplasts encoded by the nuclear genome are transported without the N-terminal transit peptide. Here, we investigated the targeting mechanism of AtOEP7, an Arabidopsis homolog of small outer envelope membrane proteins in vivo. AtOEP7 was expressed transiently in protoplasts or stably in transgenic plants as fusion proteins with GFP. In both cases AtOEP7:GFP was targeted to the outer envelope membrane when assayed under a fluorescent microscope or by Western blot analysis. Except the transmembrane domain, deletions of the N- or C-terminal regions of AtOEP7 did not affect targeting although a region closed to the C-terminal side of the transmembrane domain affected the targeting efficiency. Targeting experiments with various hybrid transmembrane mutants revealed that the amino acid sequence of the transmembrane domain determines the targeting specificity The targeting mechanism was further studied using a fusion protein, AtOEP7：NLS：GFP, that had a nuclear localization signal. AtOEP7：NLS：GFP was efficiently targeted to the chloroplast envelope despite the presence of the nuclear localization signal. Taken together, these results suggest that the transmembrane domain of AtOEP7 functions as the sole determinant of targeting specificity and that AtOEP7 may be associated with a cytosolic component during translocation to the chloroplast envelope membrane.

• 폴리머
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• 제24권1호
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• pp.72-81
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• 2000

벤조산 폴리에스테르/락톤 폴리올의 합성은 디올로서 폴리카프로락톤 0201, 트리올로서 트리메틸올프로판, 2염기산으로서 아디프산 및 1염기산으로 벤조산을 사용하였다. 폴리이소시아네이트 프리폴리머는 HDI-biuret형인 Desmodur N-100을 사용하였다. 벤조산 폴리에스테르/락톤 폴리올, 폴리이소시아네이트, 안료, 습윤분산제 및 플로우개량제 등을 블렌드하여 2성분계 폴리우레탄 도료를 제조하였다. 제조된 폴리우레탄 도료로서 도막시편을 제작하여 각종 도막 물성시험을 행한 결과 KS 규격에서 제시한 기준치와 비교하여 내마모성, 촉진내후성, 황변도는 우수하게, 굴곡성, 내충격성, 60$^{\circ}$ 경민광택도, 접착력, 내유성, 명도지수차는 양호하게, 경도는 다소 나쁘게 나타났다. 따라서 디올로서 폴리카프로락톤 0201을 도입한 후 내유성, 굴곡성, 내충격성의 장점이 나타남을 확인하였다. 또한 벤조산 함량변화에 따른 고화 및 경화거동을 살펴 본 결과, 고화에 따른 건조시간은 2~4시간으로, 경화에 따른 가사시간은 20~37시간으로 각각 나타나, 도막표면의 고화 및 경화상태가 양호함을 보여주었다.

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.183-188
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• 2012

In this study, we examined the estrogenic activity of bavachin, a component of Psoralea corylifolia that has been used as a traditional medicine in Asia. Bavachin was purified from ethanolic extract of Psoralea corylifolia and characterized its estrogenic activity by ligand binding, reporter gene activation, and endogenous estrogen receptor (ER) target gene regulation. Bavachin showed ER ligand binding activity in competitive displacement of [$^3H$] $E_2$ from recombinant ER. The estrogenic activity of bavachin was characterized in a transient transfection system using $ER{\alpha}$ or $ER{\beta}$ and estrogen-responsive luciferase plasmids in CV-1 cells with an $EC_{50}$ of 320 nM and 680 nM, respectively. Bavachin increased the mRNA levels of estrogen-responsive genes such as pS2 and PR, and decreased the protein level of $ER{\alpha}$ by proteasomal pathway. However, bavachin failed to activate the androgen receptor in CV-1 cells transiently transfected with the corresponding receptor and hormone responsive reporter plasmid. These data indicate that bavachin acts as a weak phytoestrogen by binding and activating the ER.