• 제목/요약/키워드: 2-Mercaptoethanol

검색결과 212건 처리시간 0.026초

STM Study of 2-Mercaptoethanol Self-Assembled Monolayer on Au(111)

  • 현문섭;이충균
    • Bulletin of the Korean Chemical Society
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    • 제22권2호
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    • pp.213-218
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    • 2001
  • Presented are the STM images of self-assembled monolayer of 2-mercaptoethanol on Au(111). Striped structures of ($6{\times}3_{\frac{1}{2}}$), ($5{\times}3_{\frac{1}{2}}$), ($4{\times}3_{\frac{1}{2}}$) and compact-($5{\times}3_{\frac{1}{2}}$) were observed after annealing at $80^{\circ}C.$ Analysis of the ordered structures revealed that the basic fundamental units of the ordered structures were three crystallographically non-equivalent ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies, and that the way of combination of the assemblies produced the four different structures. The($6{\times}3_{\frac{1}{2}}$) structure ( $\theta$ = 0.33) was composed of one ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$)$R30^{\circ}$ assembly, while the ($5{\times}3_{\frac{1}{2}}$) ( $\theta$ = 0.30) and ($4{\times}3_{\frac{1}{2}}$) ( $\theta$ = 0.38) structures were consisted of two ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies, separated by 5a and 4a, respectively. Furthermore, the compact-(5X 3½) structure ( $\theta$ = 0.50) was obtained by overlapping three ($3_{\frac{1}{2}}{\times}3_{\frac{1}{2}}$) $R30^{\circ}$ assemblies. In spite of the diversity in the adsorption structures, all the adsorption sites of 2-mercaptoethanol were fundamentally identical. On the other hand, the unannealed primitive SAM of 2-mercaptoethanol was characterized by two observations: a short-range order keeping the adsorbed molecules at approximately $3_{\frac{1}{2}}$ a and the small domains of the striped structures supporting that the observed surface structures on the annealed surface were the extension of the primitive layer of 2-mercaptoethanol. Comparing these observations with the already published structures of ethanthiol, it was concluded that the interaction between the hydroxyl groups of 2-mercaptoethanol might play a significant role in the adsorption step of 2-mercaptoethanol on Au(111) to organize the adsorption structures different from those of ethanthiol.

단백질 가수분해 효소 및 이황화 결합 환원제 처리가 밥의 텍스처에 미치는 영향 (Effect of Protease and Disulfide Bond Reducing Agent Treatment on the Texture of Cooked Rice)

  • 김성란;안승요
    • Applied Biological Chemistry
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    • 제38권6호
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    • pp.563-569
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    • 1995
  • 쌀 단백질이 밥의 식미와 텍스쳐에 미치는 영향을 밝히기 위하여 단백질 가수분해 효소와 이황화결합 환원제 처리가 밥의 텍스쳐에 미치는 효과에 대하여 시험하였다. 세 품종의 찰밥의 경도, 부착성, 탄력성 등은 유의한 차이가 있었다. 그 중 IR 36의 밥이 가장 단단하고 부착성이 적었다. 밥의 경도는 $4^{\circ}C$에서 12시간 저장한 후에 두드러지게 증가하였으며 경도와 부착성에 대한 품종별 차이가 뚜렷하였다. 단백질 가수분해 효소를 처리한 밥과 2-mercaptoethanol을 처리한 밥은 처리하지 않은 밥보다 밥의 수분 함량과 평윤 크기가 증가하였으며 경도의 감소와 부착성의 증가가 뚜렷하였고 관능검사에 의한 기호도가 향상되었다.

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무에서 추출한 myrosinase의 정제 및 효소학적 특성 (Purification and enzymatic characteristics of myrosinase from radish)

  • 심기환;강갑석;서권일
    • Applied Biological Chemistry
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    • 제36권2호
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    • pp.86-92
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    • 1993
  • 무에서 DEAE Bio-Gel, Con-A 및 Superose-6 칼럼을 이용하여 myrosinase를 정제하고 그 효소학적 특성을 검토한 결과 myrosinase(II)는 2개의 subunits를 가졌으며, 이들의 분자량은 SDS-GAGE상에서 각각 53 및 39 KD였다. 정제된 무효소의 비활성도는 37,500 units/mg이었으며, 정제도는 44배였다. 최적 활성 pH는 phosphate 및 Tris-HCl 완충액에서 $6.5{\sim}7.0$이었으며, pH7.0에서 그 효소활성이 가장 안정하였다. 활성 최적온도는 $37{\sim}38^{\circ}C$였고, 열안정성은 $30^{\circ}C$ 이하였다. 무 myrosinase에 대한 무기염의 영향은 구리 및 수은 이온은 효소 활성을 매우 저해하며, ascorbic acid의 농도별 영향은 1 mM일 때 최대활성을 나타내었다. Ascorbic acid analogue에 대한 활성은 dehydroascorbic acid에 대해서는 거의 없었으며, 나머지 analogue들도 ascorbic acid보다 상당히 활성이 낮았다. 무 myrosinase에 대한 환원제의 영향은 2-mercaptoethanol과 dithiothreitol에 의해서는 활성을 나타내지 않았으나, 이들을 ascorbic acid 등 2-mercaptoethanol과 함께 첨가하면 활성을 나타내었다.

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$eta$-Mercaptoethanol과 Cysteamine 첨가와 Buffalo Rat 간세포 공동배양이 소 체외수정란의 체외발육과 세포내 Glutathione 농도 변화에 미치는 영향 (Effect of $eta$-Mercaptoethanol and Cysteamine with Buffalo Rat Liver Cells(BRLC) on Development and Intracellular Glutathione Concentrations of Bovine IVM/IVF Embryos)

  • 박동헌;양부근;황환섭;정희태;박춘근;김종복;김정익
    • 한국수정란이식학회지
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    • 제12권3호
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    • pp.277-282
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    • 1997
  • The purpose of this experiment was to determine the effects of thiol compounds, $\beta$-mercaptoethanol($\beta$-ME) and cystearrone with buffalo rat liver cell(BRLC) co-culture on the development and intracellular glutathione(GSH) concentrations of bovine embryos produced by in vitro inaturation(IVM) and in vitro fertilization(IVF). Bovine IVM /IVF embryos developed to 2~8 cell stage were co-cultured with BRLC in GRlaa with or without thiol compounds. The developmental rate beyond morulae stage in CRlaa containing 0, 10,25 and 50$\pi$M $\beta$-ME with BRLG were 63.0, 74.0, 72.3 and 77.1%, respectively. And the developmental rate with 0, 25, 50 and 75$\pi$M cystearnine with BRLC were 69.6, 77.6, 81.0 and 76.8%, respectively. The developmental rate beyond morulae stage of GRlaa containing thiol compound with BRLG group was higher than that of control group. The intracellular GSH concentrations of blastocysts cultured for 5 days in GRlaa containing 0 and 50$\pi$M $\beta$-ME or cysteamine with BRLG were 81.2 and 86.4, 83.2 and 84.2pM, respectively. The intracellular GSH concentrations of blastocysts in GRlaa containing thiol compounds with BRLG was slightly higher than that of control group The cell numbers of blastocysts were not difference in all experimental groups. These results indicate that thiol compounds with BRLG co-culture was increased the percentage of developed into morulae and blastocysts, and intracellular GSII concentrations of blastocysts embryos.

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$\beta$-Mercaptoethanol과 Cysteamine 첨가와 소 난관상피세포 공동배양이 소 체외수정란의 체외발육과 세포내 Glutathione 농도 변화에 미치는 영향 (Effect of $\beta$-Mercaptoethanol and Cysteamine With Bovine Oviduct Epithelial Cells on Development and Intracellular Glutathione Concentrations of Bovine IVM/IVF Embryos)

  • 박동헌;양부근;김준국;정희태;박춘근;김종복;김정익
    • 한국수정란이식학회지
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    • 제12권3호
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    • pp.269-276
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    • 1997
  • The objective of this study was to investigate the effects of thiol compounds with bovine oviduct epithlial crlls(BOEC) co culture on development and intracellular glutathione(GSH) concentrations of bovine embryos derived from IVM /IVF oocytes. In experiment 1 and 2, embryos developed to 2~8 cell stage after in vitro fertilization were co-cultured with BOEC in CR$_1$aa with or without $\beta$-mercaptoethanol($\beta$-ME) and cysteamine. The percentage of embryos that developed to morulae and blastocysts in 0,10, 25 and 5O$\pi$M $\beta$-ME with BOEC was 48.1, 64.0, 72.9 and 75.9%, respectively. Twenty-five and 5O$\pi$M $\beta$-ME groups were significantly higher than in 0 and 1O$\pi$M $\beta$- -ME groups(P$\pi$M cysteamine with BOEC was 50.0, 53.2, 72.0 and 66.7%, respectively. Fifty $\pi$M cysteamine group was significantly higher than any other groups (P$_4$aa with 0 and 5O$\pi$M $\beta$-ME or cysteamine were 68.5, 77.8, 78.7 and 80.0pM, respectively. Fifty $\pi$M $\beta$-ME group was significantly higher than that of control(P<0.05), but cysteamine group was not. Cell numbers of blastocysts were not difference in all experimental groups. These experiments indicate that $\beta$-ME and cysteamine with BOEC co-culture can affect the development and intracellular GSH concentrations of bovine embryos produced by IVM /IVF docytes.

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화학적 처리방법에 의한 효모의 세포벽 제거 (The Disruption Yeast Cell Wall by chemical Treatment)

  • 문정혜;김중균
    • 생명과학회지
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    • 제8권2호
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    • pp.197-202
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    • 1998
  • 효모를 먹이로 하는 filter-feeder들의 소화력을 높이고자, algae의 대용물로서 가치가 있는 Kluyveromuces fragilis효모를 화학적 처리방법에 의해 세포벽을 바괴시켰다. 화학적 처리방법의 최적조건은 0.2 M Tris-buffer에 용해시켜 만든 1M 의 $Na_2EDTA$와 0.3 M의 2-mercaptoethanol을 처리한 후 $30{\circ}C$배양기에서 1시간 배양하는 조건에서 얻어졌다. 이때, 약 30%의 protoplast yeast를 실시함으로써, 그 생성률을 약 2배이상 올릴 수 있었다.

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3% NaCl용액중에 있어서 4340강의 부식거동과 과방식에 의한 수소포화거동에 미치는 인히비타의 영향 (The effect of inhibitors affecting to corrosion behaviors and hydrogen embrittlement behaviors due to over-propection of a 4340 steel in 3% NaCl solution)

  • 문경만;백태실;이상태
    • Journal of Advanced Marine Engineering and Technology
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    • 제13권4호
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    • pp.54-62
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    • 1989
  • When some kinds of inhibitors, i.e. $1{\times}10{-3}mol/l$ arsenic trioxide, 0.2 mol/l 2-mercaptoethanol, 0.2mol/l thiourea were added to 3% NaCl solution, there were some considererable effects to decrease corrosion current density in natural potential condition and the effect fo solution temperature increasing corrosion rate was smaller than that of no addition to 3% NaCl solution. However the susceptibility of hydrogen embrittlement due to over-protection in case of cathodic protection was much greater than that of no addition, especially was the greatest in case of addition of 2-mercaptoethanol. Therefore adding inhibitors for anti-corrosion effect, it is suggested that selection of the optimum protection potential is important from the view point of prevention against hydrogen embrittlement due to over-protection in case of cathodic protection.

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고구마 $\beta$아밀라아제의 안정성에 관한 연구(2) (Stability of Sweet Potato $\beta$Amylase (II))

  • 안용근;이석건
    • 한국식품영양학회지
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    • 제9권3호
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    • pp.253-258
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    • 1996
  • Stabilities of sweets potato f-amylase on various reagents were studied. The enzyme was stabilized by bovine serum albumin, Triton X-100 and 2-mercaptoethanol of 0.04%. Among them, bovine serum albumin was the most effective. And enzyme stability was increased by using the deairated solution. The enzyme activity was remained 0% in the absence of glycerol, 25% in the presence of 20% glycerol and 50% in the presence of 40% glycerol at 37$^{\circ}C$, for 15 hours in pH 11. SDS inhibited the enzyme, and 2-mercaptoethanol and dithiothreitol stabilized it.

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Saccharomyces cerevisiae D-71과 Zygosaccharomyces rouxii SR-S의 원형질체 형성과 융합 (Protoplast Formation and Fusion between Saccharomyces cerevisiae D-71 and Zygosaccharomyces rouxii SR-S)

  • 이종수;김찬조
    • 한국미생물·생명공학회지
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    • 제16권2호
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    • pp.142-149
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    • 1988
  • 고온에서 고농도 기질을 발효할 수 있는 효모를 육성하고자 8%의 NaCl 내성을 갖은 고온발효성인 Saccharomyces cerevisiae D-71 과 Ca-pantothenate 를 절대요구하는 내삼투압성인 Zygosaccharomyces rouxii SR-S를 친주로 하여 원형질체 형성과 융합조건을 검토하였다. Sacch. cerevisiae D-71은 YEPG 배지에 12시간 배양한 세포를 0.1mM EDTA와 0.5M sorbitol를 함유한 인산완충액(pH7.5)에 현탁시켜 1%의 2-mercaptoethanol로 10분간 전처리한 후 Zymolyase-20T 4.0mg/$m\ell$를 가하여 3$0^{\circ}C$에서 50분간 반응시켰을 때 96% 이상의 수율로 윈형질체가 형성되었고 Zygosacch. rouxii SR-S는 YEMEPG 배지에 24시간 배양한 세포를 0.1mM EDTA와 0.5~l.0M mannitol을 함유한 인산완충액(pH7.0)에 현탁시켜 1%의 2-mercaptoethanol로 10분간 전처리 한 후 Zymolyase-20T 4.0mg/$m\ell$를 가하여 3$0^{\circ}C$에서 120분간 반응시켰을 때 95% 정도의 수율로 원형질체가 형성되었다. 시험효모의 원형질체를 CaCl$_2$와 Sorbitol 및 40% 의 PEG 4000을 함유한 융합배지에 1 : 1로 혼합한 후 35$^{\circ}C$에서 20분간 처리하여 융합시킨 다음 3%의 한천을 함유한 최소배지에 중층하여 5일간 배양하였을 때 9.1$\times$$10^{-6}$의 융합빈도수를 보였다. 또한 주사형전자현미경으로 구형의 원형질체와 융합재생된 타원형의 세포를 관찰할 수 있었다.

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Acetoacetanilide 유도체 합성 (Studies on the Synthesis of Acetoacetanilide Derivatives)

  • 김인규
    • 대한화학회지
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    • 제25권1호
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    • pp.44-49
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    • 1981
  • Acetoacetanilide를 브롬화한 결과 예상한 ${\alpha}$-bromo 유도체가 얻어지지 않고, r-bromo 유도체가 얻어졌다. 이것을 mercaptoethanol과 반응시켜 sulfide 유도체를 만든다음, 산성하에서 고리화시킨 결과 2-(N-phenylcarbamoyl)methylene-1,4-oxathiane이 좋은 수율로 얻어졌다. 이 물질은 살균제 농약으로 널리 사용되고 있는 carboxin과 그 구조가 매우 유사하므로 이 물질의 biological activity는 흥미있는 과제가 될 것이다.

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