• 약학회지
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• 제35권3호
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• pp.222-230
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• 1991

Polyphenol oxidase (PPO) was purified from an extract of Perillae Folium by ammonium sulfate fractionation and sephadex G-150 gel filtration, which molecular weight estimated 65,000$\pm$1,000 in SDS-gel electrophoresis, and pI value was 4.8. The pH and temperature optima were 6.0 and $30^{\circ}C$ respectively. $K_{m}$ values of the PPO for various phenolics derived from Lineweaver-Burk plots were 4.0$\times$10$^{-4}$, caffeic acid; 4.2$\times$10$^{-3}$M, 4-methylcatechol. The inhibition by 4-nitrocatechoi, potassium cyanide, cysteine, 2-mercaptoethanol was competitive with $K_{i}$ values of 7.6$\times$10$^{-5}$M, 7.2$\times$10$^{-5}$M, 3.6$\times$10$^{-5}$M, 2.2$\times$10$^{-5}$M, respectively. Among the divalent cations, Cu$^{2+}$ ion was strong activator on PPO and Zn$^{2+}$, Ni$^{2+}$ ions were little effect on PPO activity. In comparing the amino acid composition of Perillae Folium PPO with that of wheat isozyme, grape, spinach showed similarity. But the content of glycine phenylalanine was abundant relatively.

• 대한화학회지
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• 제57권5호
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• pp.612-617
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• 2013

The versatile, hitherto unreported 3-(4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-yl)-3-oxopropanenitrile 3 was prepared by two convenient routes: either by the reaction of ethyl 4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-carboxylate 2 with acetonitrile in the presence of sodium hydride or by treatment of 4-(2-phenyldiazenyl)-3-(2-bromoacetyl)-2H-chromen-2- one 5 with potassium cyanide. Reaction of 3 with heterocyclic diazonium salts 6, 7, 14 and 17 furnished the corresponding hydrazones 8, 9, 15 and 18. The latter hydrazones underwent intramolecular cyclization into the corresponding pyrazolo[5,1- c]-1,2,4-triazine 10, 1,2,4-triazolo[5,1-c]-1,2,4-triazine 11, 1,2,4-triazino[4,3-b]indazole 16 and imidazo[2,1-c]-1,2,4-triazine 19 derivatives, respectively upon refluxing in pyridine.

• 대한화학회지
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• 제68권3호
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• pp.139-145
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• 2024

This study aims to elucidate the mechanism involved in the hydrolysis of the hexacyanoferrate(III) complex ion (Fe(CN)₆^3-) and the mechanism leading to the formation of Prussian blue (Fe^III₄[Fe_II(CN)₆]₃·xH₂O, PB) in acidic aqueous solutions at moderately elevated temperatures. Hydrolysis constitutes a crucial step in generating PB through the widely used single-source or precursor method. Recent PB syntheses predominantly rely on the single-source method, where hexacyanoferrate(II/III) is the exclusive reactant, as opposed to the co-precipitation method employing bare metal ions and hexacyanometalate ions. Despite the widespread adoption of the single-source method, mechanistic exploration remains largely unexplored and speculative. Utilizing UV-vis spectrophotometry, negative-ion mode liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and a devised reaction, this study identifies crucial intermediates, including aqueous Fe^2+/3+ ions and hydrocyanic acid (HCN) in the solution. These two intermediates eventually combine to form thermodynamically stable PB. The findings presented in this research significantly contribute to understanding the fundamental mechanism underlying the acid-catalyzed hydrolysis of the hexacyanoferrate(III) complex ion and the subsequent formation of PB, as proposed in the sequential mechanism introduced herein. This finding might contribute to the cost-effective synthesis of PB by incorporating diverse metal ions and potassium cyanide.

• 동국한의학연구소논문집
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• 제7권2호
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• pp.149-154
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• 1999

생쥐의 전뇌허혈(全腦虛血) 모델에서 potassium cyanide 유발(誘發) 혼수시간(昏睡時間) 및 생존시간(生存時間), 감압성(減壓性) 무효소(無酵素) 부하시(負荷時) 생존시간(生存時間)을 측정(測定)하여 전뇌처혈시(全腦處血時) 뇌순환대사(腦循環代謝) 개선(改善) 효과(效果)를 관찰(觀察)하였다. KCN 유발(誘發) 혼수시간(昏睡時間)의 단축(短縮), 치사양(致死量)의 KCN에 대한 생존시간(生存時間)의 연장(延長), 감압(減壓)에 의한 무산소(無酸素) 부하시(負荷時) 생존시간(生存時間)의 연장(延長) 효과(效果)가 나타났다.

• The Korean Journal of Physiology and Pharmacology
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• 제13권1호
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• pp.15-22
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• 2009

This study was undertaken to elucidate the underlying mechanisms of ATP depletion-induced membrane transport dysfunction and cell death in renal proximal tubular cells. ATP depletion was induced by incubating cells with 2.5 mM potassium cyanide(KCN)/0.1 mM iodoacetic acid(IAA), and membrane transport function and cell viability were evaluated by measuring $Na^+$-dependent phosphate uptake and trypan blue exclusion, respectively. ATP depletion resulted in a decrease in $Na^+$-dependent phosphate uptake and cell viability in a time-dependent manner. ATP depletion inhibited $Na^+$-dependent phosphate uptake in cells, when treated with 2 mM ouabain, a $Na^+$ pump-specific inhibitor, suggesting that ATP depletion impairs membrane transport functional integrity. Alterations in $Na^+$-dependent phosphate uptake and cell viability induced by ATP depletion were prevented by the hydrogen peroxide scavenger such as catalase and the hydroxyl radical scavengers(dimethylthiourea and thiourea), and amino acids(glycine and alanine). ATP depletion caused arachidonic acid release and increased mRNA levels of cytosolic phospholipase $A_2(cPLA_2)$. The ATP depletion-dependent arachidonic acid release was inhibited by $cPLA_2$ specific inhibitor $AACOCF_3$. ATP depletion-induced alterations in $Na^+$-dependent phosphate uptake and cell viability were prevented by $AACOCF_3$. Inhibition of $Na^+$-dependent phosphate uptake by ATP depletion was prevented by antipain and leupetin, serine/cysteine protease inhibitors, whereas ATP depletion-induced cell death was not altered by these agents. These results indicate that ATP depletion-induced alterations in membrane transport function and cell viability are due to reactive oxygen species generation and $cPLA_2$ activation in renal proximal tubular cells. In addition, the present data suggest that serine/cysteine proteases play an important role in membrane transport dysfunction, but not cell death, induced by ATP depletion.

• Applied Biological Chemistry
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• 제24권3호
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• pp.167-173
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• 1981

마늘의 갈변현상중(褐變現象中) 효소적(酵素的) 갈변(褐變)에 관여(關與)하는 polyphenol oxidase 조효소액(粗酵素液)을 추출(抽出)하여 그 성질(性質)을 몇가지 조사(調査)하였다. 기질(基質)로서는 여러 phenol화합물(化合物)들을 사용(使用)해 본 결과(結果), diphenol류(類)와 monophenol류(類)는 거의 갈변(褐變)되지 않았으나 triphenol인 pyrogallol, gallic acid는 크게 갈변(褐變)되는 것으로 보아 마늘의 polyphenol oxidase는 triphenol oxidase로 보인다. 이 효소의 최적(最適) pH는 6.5 부근으로 약산성측(弱酸性側)에 있었으며 열안정성(熱安定性)은 $80^{\circ}C$, 5분(分) 가열(加熱)로 90%의 잔존율(殘存率)을 보여 열(熱)에 매우 안정(安定)하였다. Na-metabisulfite는 1mM의 농도(濃度)에서 안전(完全)한 조해(阻害)를 하였고, potassium cyanide, L-ascorbic acid, thiourea순(順)으로 효소활성(酵素活性)을 조해(阻害)하였다. $Mg^{2+}$는 효소활성(酵素活性)을 증가(增加)시켰고 $Cu^{2+}$는 저농도(低濃度)(1mM)에서는 polyphenol oxidase가 활성화(活性化)하는데 비(比)해 고농도(高濃度)(10mM)에서는 조해작용(阻害作用)을 하였다. 마늘의 polyphenol oxidase의 Km치(値)는 0.4mM이었다.

• 한국임상수의학회지
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• 제4권2호
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• pp.473-481
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• 1987

This experiment was performed in order to establish a proper method to determine the half life of indocyanine green(ICG T$\frac{1}{2}$) and its fractional clearance rate(KICG) and investigate the applicability of indocyanine green ( ICG ) excretion test in hepatotoxicity experiment in Korean black goats. The results were as follows : 1. Maximum absorbance of ICG in plasma was at 810 nm in this experiment. 2. The coefficient of correlation between the results obtained by standard method and potassium cyanide method was 0.99 and the regression equation between two methods was y=0.9996 x＋0.0065. 3. As the disappearance curve of ICG plotted in semi-log graph revealed linear pattern at least for 6 minutes after injection, the postinjection blood samples were decided to collect at 2 and 6 minutes after ICG injection. 4. ICG T$\frac{1}{2}$ and KICG values were not affected by dose level of ICG. 5. When 0.25 mg of ICG per kg body weight was administered the normal data of ICG T$\frac{1}{2}$ and KICG in Korean black goa were 1.468${\pm}$0.197 minutes(mean${\pm}$SD) and 0.482${\pm}$0.076/minutes respectively. 6. After administration of carbon tetracholride. the ICG T$\frac{1}{2}$ started to increase acutely from day 1, revealed the peak at day 3, and then returned almostly but not completely to preinjection level at day 14. The ICG T$\frac{1}{2}$ value was suggested to be a sensitive indicator of hepatic injury in Korean black goats.

• 분석과학
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• 제8권4호
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• pp.611-615
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• 1995

The design of appropriate chemically modified electrodes should allow development of new voltammetric measurement schemes with enhanced selectivity and sensitivity. Microorganism like algae has high ability to trap toxic and heavy metal ions and different affinities for metal ions. A copper(II) ion-selective carbon paste electrode was constructed by incorporating alga Anabaena into a conventional carbon paste mixture, and then the film of 10% Nafion was coated to avoid the swelling of the electrode surface. Copper ion could be deposited at the 25% algamodified electrode for 15 min without the applied potential while stirring the solution by only immersing the electrode in a buffer (pH 4.0) cot1taining copper(II). Temperature was controlled at $35^{\circ}C$. After preconcentration was carried out the electrode was transferred to a 0.1 M potassium chloride solution and was reduced at -0.6 volt at $25^{\circ}C$. The differential pulse anodic stripping voltammetry was employed. A well-defined oxidation peak could be obtained at -0.1 volt (vs SCE). In five deposition / measurement / regeneration cycles, the responses were reproducible and relative standard deviations were 3.3% for $8.0{\times}10^{-4}M$ copper(II). Calibration curve for copper was linear over the range from $2.0{\times}10^{-4}M$ to $1.0{\times}10^{-3}M$. The detection limit was $7.5{\times}10^{-5}M$. Studies of the effect of diverse ions showed that the coexisting metal ions had little or no effect for the determination of copper. But anions such as cyanide. oxalate and EDTA seriously interfered.

• 생명과학회지
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• 제25권5호
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• pp.487-495
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• 2015

Pseudomonas pseudoalcaligenes KF707에서 정제한 protocatechuate 3,4-dioxygenase의 특징을 조사하기 위하여 pH안정성, 화학적 저해, 화학적 수식과 pH의존성 반응 상수에 대한 실험을 수행하였다. 이 효소는 pH 4.5~10.7에서 안정하였다. L-ascorbate와 glutathione은 Kis가 각각 0.17 mM과 0.86 mM인 경쟁적 저해제였으며, DL-dithiothreitol은 Kis 1.57 mM 및 Kii 8.08 mM의 비경쟁적 저해패턴을 나타내었다. Potassium cyanide, p-hydroxybenzoate 및 sodium azide는 Kis가 각각 55.7 mM, 0.22 mM 및15.64 mM이었으며, Kii는 각각94.1 mM, 8.08 mM, 및 662.64 mM인 비경쟁적 저해패턴을 나타내었다. $FeCl_{2}$는 Kis가 $29{\mu}M$로 가장 우수한 경쟁적 저해제였으며, $FeCl_{3}$, $MnCl_{2}$, $CoCl_{2}$, $HgCl_{2}$, $AlCl_{3}$도 각각 Kis가 1.21 mM, 0.85 mM, 3.98 mM, 0.17 mM 및 0.21 mM인 경쟁적 저해패턴을 보였다. 한편, 다른 금속이온들은 비경쟁적 저해패턴을 나타내었다. pH의존성 반응상수의 실험결과로부터 pK 6.2와 9.4의 촉매부위와 pK 5.5와 9.0의 결합부위가 존재함을 알 수 있었다. Lysine, cysteine, tyrosine, carboxyl과 histidine은 각각의 고유한 화학적 수식제에 의해 수식되었는데, 이는 이들 잔기들이 결합과 촉매에 관여한다는 것을 나타낸다. 위 결과를 토대로 화학적 메커니즘을 제시한다.

• 한국균학회지
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• 제15권2호
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• pp.99-170
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• 1987

Coriolus versicolor가 생산(生産)하는 laccase 생산(生産) 조건(條件)과 그 특성(特性)을 검토하여 다음과 같은 결과를 얻었다. Laccase 생산(生産)은 영양적 최적(最適) 조건(條件)은 indulin AT1%, peptone 0.3%, $KH_2PO_4$ 0.1%, $MgSO_4$ 0.02%, $CuSO_4$ 0.1mg%, thiamine HCI 0.005 mg%였다. Laccase 생산(生産)의 최적(最適) 온도(溫度)는 $25^{\circ}C$ 최적(最適) pH는 5.0이었고 배양기간(培養期間)은 20日이었다. Laccase 작용(作用) 최적(最適) pH는 4.6이었고 최적온도(最適最適)는 $40^{\circ}C$였으며 pH 안정성은 $40^{\circ}C$에서 15분간 보존(保存)하였을 때 pH4.6에서 가장 안정하였다. 열안정성(熱安定性)은 $40^{\circ}C$ 이하에서 는 비교적 안정하였으나 그 이상 올라갈수록 열에 민감한 반응(反應)을 보였고 sodium azide 1mM차 KCN 1mM에서 완전 저해(沮害)되었다.