• 미생물학회지
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• 제10권3호
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• pp.106-108
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• 1972

The enzyme was produced by Asp.oryzae SHW 131. the enzymatic properties of .alpha.-amylase are following : 1) Crystallization of .alpha.-amylase is formed of longish square. 2) The range of stable pH is 5-10 and optimum ph is 5.5. 3) It is very unstable enzyme about EDTA and protection by $Ca^{++}$ ion and best activated at $50^{\circ}C$ about temperature. 4) Asp.oryzae SHW 131 produced .alpha.-amylase with acid-protease, neutral-protease and tepid-alkalin-protease.

• 미생물학회지
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• 제10권3호
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• pp.105-105
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• 1972

The enzyme was produced by Asp.oryzae SHW 131. the enzymatic properties of .alpha.-amylase are following : 1) Crystallization of .alpha.-amylase is formed of longish square. 2) The range of stable pH is 5-10 and optimum ph is 5.5. 3) It is very unstable enzyme about EDTA and protection by $Ca^{++}$ ion and best activated at $50^{\circ}C$ about temperature. 4) Asp.oryzae SHW 131 produced .alpha.-amylase with acid-protease, neutral-protease and tepid-alkalin-protease.

• 한국미생물·생명공학회지
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• 제15권6호
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• pp.375-380
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• 1987

Alcaligenes eutrophus A52의 무세포 추출액으로부터 유안염석 및 DEAE-cellulose 이온교환 크로마토그래피로서 D-$\alpha$-Amino-$\varepsilon$-Caprolactam(DAC) racemase 와 L-$\alpha$-Amino-$\varepsilon$-Caprolactam(LAC) hydrolase를 분획하였다. A. eutrophus A52에 의한 DAC로부터 L-lysine으로의 전환은 DAC가 racemase에 의해 LAC로 전환된 후 hydrolase에 의해 L-lysine으로 가수분해됨을 확인하였다. DEAE-cellulose 이온교환 크로마토그래피에 의해 분리된 racemase의 분획은 최적온도가 55$^{\circ}C$, 최적 pH는 8.0이었으며 hydrolase의 분획은 최적온도가 $65^{\circ}C$ 최적 pH가 9.0이었다. 이 두 효소를 모두 함유하는 무세포 추출 액에 의한 DAC로부터 L-lysine으로의 전환은 6$0^{\circ}C$와 pH8.5에서 최대를 나타내었고 2% 이상의 DAC와 L-lysine에 의해 상당한 저해를 받았으나 0.5% DAC를 3.1mg의 단백질에 상당하는 무세포 추출액으로서 전환시킨 결과 55$^{\circ}C$에서 10시간 동안에 약 98%가 L-lysine으로 전환되었다.

• 약학회지
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• 제36권4호
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• pp.390-396
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• 1992

Streptomyces minoensis DMCJ-144 isolated from soil produces the ${\alpha}-amylase$ inhibitor. Optimum culture conditions for ${\alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $CuSO_4{\cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{\circ}C$, the maximum production of the ${\alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.

• 한국식품영양학회지
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• 제11권2호
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• pp.159-164
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• 1998

고구마 $\beta$-아밀라아제를 NaIO4-산화 가용성 전분으로 변형하여 안정성을 측정하였다. 그 결과, 치적안정 pH는 3 및 4를 나타냈고, pH 3, 5~9, 11에서 비변형 효소보다 높은 안정성을 나타냈다. 6$0^{\circ}C$에서 15분 동안 변형효소는 비변형 효소보다 안정성이 증가하였다. 변형 보리 $\beta$-아밀라아제는 전체 pH에 걸쳐서 넓은 pH 안정성을 나타냈고, $\alpha$-cyclodextrin은 이를 더욱 증가 시켰다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.662-665
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• 2001

PLE를 이용한 levofloxacin의 생산에서 기질 150 mM 사용의 경우 두배의 몰농도 로 ${\alpha}-CD$를 사용하여 산물의 생산량을 3.7 배까지 증가시킬 수 있었다. 그러나 이 경우 ${\alpha}-CD$의 사용량이 많아 경제성이 떨어지는 단점이 있다. 이에 같은 몰농도로 ${\alpha}-CD$를 사용하고 pH에 변화를 주어 용해도를 향상시켜 보았다. 기질 100 mM의 경우 pH 5.6에서 같은 몰농도의 ${\alpha}-CD$를 사용한 경우 ${\alpha}-CD$를 사용하지 않은 것에 비해 4.4배의 수율의 증대가 있었다.

• 한국식품영양학회지
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• 제13권4호
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• pp.342-347
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• 2000

과요오드산-산화전분으로 보리 $\beta$-amylase(Bio-zyme ML, 일본 아마노제약)를 변형시켜서 인공당단백질을 만들었다. pH 8.0에서 변형한 효소는 비변형효소의 92%, pH 9.7에서 변형한 효소는 42%의 활성이 남았다. 6$0^{\circ}C$에서의 열안정성은 $\alpha$-cyclodextrin ( $\alpha$-CD) 존재 시에 변형하여 $\alpha$-CD존재시 분석한 효소는 10분 뒤에 비활성의 8%가 남은 반면 변형하지 않은 효소는 4.5%밖에 남지 않았다. pH안정성은 변형 시켜서 $\alpha$-CD존재 하에 분석한 효소가 가장 높아서 pH 2~5와 7~12에서 안정성이 매우 증가하였다. HPLC분석 결과 효소는 두 개의 피크를 나타냈으며 변형시킨 것은 당결합으로 분자량이 커져서 유출시간이 약간 빨라졌다.

• Transactions on Electrical and Electronic Materials
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• 제5권5호
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• pp.189-193
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• 2004

Pure and Sn or Pt doped $\alpha-Fe_2O_3$ thin films were prepared on $Al_2O_3$ substrates by RF-magnetron sputtering method and the sensitivities were compared. It was found that pure $\alpha-Fe_2O_3$ thin films did not exhibit much selectivity in CO and $i-C_4H_{10}$ gases while it showed the high sensitivity in proportion to the gas concentration of $C_2H_{5}OH$ gas. Pt-doped $\alpha-Fe_2O_3$ showed to be alike sensing properties as pure $\alpha-Fe_2O_3$ thin film in $C_2H_{5}OH$ gas. However, Sn-doped $\alpha-Fe_2O_3$ thin films exhibited the excellent sensitivity and selectivity in Hz gas. After microstructure modification by plasma etching on pure $\alpha-Fe_2O_3$ thin films, the gas sensing characteristics were dramatically changed.

• Archives of Pharmacal Research
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• 제28권12호
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• pp.1392-1399
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• 2005

This study evaluated the effect of $\alpha$-tocopherol ($\alpha$-TC), ischemic preconditioning (IPC) or a combination on the extent of mitochondrial injury caused by hepatic ischemia/reperfusion (I/R). Rats were pretreated with $\alpha$-TC (20 mg/kg per day, i.p.) for 3 days before sustained ischemia. A rat liver was preconditioned with 10 min of ischemia and 10 min of reperfusion, and was then subjected to 90 min of ischemia followed by 5 h or 24 h of reperfusion. I/R increased the aminotransferase activity and mitochondrial lipid peroxidation, whereas it decreased the mitochondrial glutamate dehydrogenase activity. $\alpha$-TC and IPC individually attenuated these changes. $\alpha$-TC combined with IPC ($\alpha$-TC+IPC) did not further attenuate the changes. The mitochondrial glutathione content decreased after 5 h reperfusion. This decrease was attenuated by $\alpha$-TC, IPC, and $\alpha$-TC+IPC. The significant production of peroxides observed after 10 min reperfusion subsequent to sustained ischemia was attenuated by $\alpha$-TC, IPC, and $\alpha$-TC+IPC. The mitochondria isolated after I/R were rapidly swollen. However, this swelling rate was reduced by $\alpha$­TC, IPC, and $\alpha$-TC+IPC. These results suggest that either $\alpha$-TC or IPC reduces the level of mitochondrial damage associated with oxidative stress caused by hepatic I/R, but $\alpha$- TC combined with IPC offers no significant additional protection.

• Bulletin of the Korean Chemical Society
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• 제13권5호
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• pp.474-479
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• 1992

Molecular interaction between ${\alpha}$-cyclodextrin and aspirin was studied by UV, $^2H$-NMR and $^2H$-NMR spectroscopy analyses for solution complex and by FT-IR analyses for solid complex. The inclusion structure provides a basic understanding of the aspirin and ${\alpha}$-cyclodextrin interaction.