• YAKHAK HOEJI
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• v.22 no.4
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• pp.215-218
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• 1978

It is known that hydantoin derivative can be synthesized according to the method of Bucherer-Bergs, which employs the interaction of the carbonyl compounds with potassium cyanide and ammonium carbonate in dilute alcohol solution. In a converting study of .alpha.-dietylaminoacetophenone with KCN and ($NH_{4})_{2}CO_{3}$ to hydantoin, the attempted 5-diethylaminomethyl-5-phenylhydantoin was not formed. In this reaction diethylaminomethly group was unexpectedly eliminated and 5-phenylhydantoin was obtained, instead of the anticipated compound.

• YAKHAK HOEJI
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• v.4 no.1
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• pp.47-49
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• 1959

Another application of the new quantitative analytical method of prussic acid by "Microdiffusion analysis" for the determination of prussic acid in human blood was studied. The blood containing potassium cyanide was dropped in outer room of unit, and then N-sulfuric acid was added. The liberated HCN gas was absorbed into nickel sulfate solution of inner room, afterward, absorbed prussic acid was determined with EDTA by residual titration. The result was coincided with the result of Liebig Denigs' method at ordinary temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.309-318
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• 2005

Higher level of KCl application stimulated both leaf area index and leaf area duration in all cassava varieties, while the leaf and tuber number of the bitter varieties (high cyanide-level varieties) decreased in proportion to the level of KCl application. The root/shoot (R/S) ratio and harvest index (HI) were negatively related with the level of KCl application in all cassava varieties. The bitter varieties obtained the lowest R/S ratio at the level of 100 - 150 kg KCl $ha^{-1}$, while the sweet varieties (low cyanide-level varieties) acquired the highest values at the level of 50 - 150 kg KCl $ha^{-1}$. Also, the sweet varieties showed the lowest HI at the level of 250 kg KCl $ha^{-1}$, but the bitter varieties at the level of 150 kg KCl $ha^{-1}$. At 6 - 8 months after planting, the sweet varieties tended to obtain higher starch content of roots (tubers) at the level of 50 - 150 kg KCl $ha^{-1}$, while the bitter varieties at the level of 150 - 250 kg KCl $ha^{-1}$. Relatively lower level of 50 - 150 kg KCl $ha^{-1}$ was more appropriate for decreasing hydrocyanic acid (HCN) content of roots (tubers) in the sweet varieties at the harvest time, and the level of 250 kg KCl $ha^{-1}$ was adequate to decrease not only HCN content of leaves but also that of roots (tubers) in the bitter varieties during the growing period. To obtain higher yield and starch content of tubers, and lower HCN content of roots (tubers), it was recommended that the sweet varieties are applied with the level of 50 - 100 kg KCl $ha^{-1}$ and the bitter varieties with the level of 150 - 200 kg KCl $ha^{-1}$, respectively, in Latosol soils of Bogor areas, West Java.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.110-117
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• 1987

Polyphenol oxidase in Prunus salicina(Red) was extracted, some properties and its partially purification were investigated as follows; Polyphenol oxidase was purified about 15 folds after ammonium sulfate saturation and about 64 folds after Sephadex G-100 column chromatography. Polyphenol oxidase showed optimum pH for activity at 6.5 and optimum temperature at at $35^{\circ}C$ and high affinity to catechol in o-diphenol compounds. Thermal stability were about 85% and 75% of initial polyphenol oxidase activity remained after heating at $50^{\circ}C$ for 5 minutes and 30 minutes respectively. The Michaelis constant of the enzyme was 2.58mM. L-cysteine, glutathione, ascorbic acid and potassium cyanide appeared to be most effective inhibitors. EDTA showed a slight inhibition.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.281-283
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• 1994

5-sec-butylthiomethyl-5-alkyl (methyl or phenyl) hydantoins (3-x) were prepared by the reaction of sec-buylthiomethyl alkyl (methyl or phenyl) ketone (1-2), potassium cyanide and ammonium carbonate. 3-(2-Bromoethyl) hydantoins (5-6) were the reaction products of 5-sec-buythiomethyl-5-alkyl (methyl or phenyl) hydantoin and 1, 2-dibromothane in the presence of potassium hydroxide. Alkylation of 5 and 6 with an excess of alkyl (methyl or ethyl iodide in THF with sodium hydride as base gave three 1-alkyl (methyl or ethyl)-3-(2-bromoethyl) hydantoins (7-9). Treatment of the 2-bromothyl group with potassium thioacelate and triethylamine gave three 1-alkyl (methyl or ethyl)-3-92-acetylthioethyl) hydantoins (10-12). Hydrolysis of the 2-acetylthiuoethyl group with sodium hydroxide in methanol afforded the three 1-alkyl (methyl or ethyl)-3-(2-mercaptorthyl) hydantoins.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.714-719
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• 1996

For the fabrication of the circuits, contact or terminal areas are usually coated with nickel and gold. Usually, diluted palladium solution is applied to initiate electroless nickel plating on the copper circuits. However, the trace amounts of palladium remains on the resin and it causes the extraneous deposition. We confirmed that selectivity was greatly improved by the treatment with the strong reducing agents such as SBH or DMAB. Bondability was greatly influenced by the contents of phosphorus in the deposited nickel. Stabilizers in the electroless gold plating were also influenced the bonding strength. The baths containing cupferron or potassium nickel cyanide as a stabilizer showed superior bondability. The gold deposits having strong orientation with Au(220) and Au(311) showed good bond ability.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.237-241
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• 2002

Polyphenoloxidase activity (PPO) in the leaves of Erechitites hieracifolia was estimated by Warburg's manometric method. The emzyme was most reactive toward chlorogenic acid followed by caffeic acid. Diethyldithiocarbamate and potassium cyanide were shown powerful inhibition rate to the polyphenoloxidase from the leaves of Erechitites hieracifolia. We confirmed antioxidant activity of the leaves of Erechitites hieracifolia by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging method. Electrophorectic isoenzyme banding patterns of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were observed by native PAGE. The correlation of PPO and antioxidant enzymes is not investigated yet. That is need to further study.

• Korean Journal of Microbiology
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• v.29 no.4
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• pp.238-242
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• 1991

Extracellular laccase secreted from Pleurotus ostreatus was activated by $Cu^{2+}$ and $Cu^{+}$ . The enzyme was strongly inactivated by 8-hydroxyquinoline, potassium cyanide, sodium azide, sodium bisulfite and 2-mercaptoethanol. The two ionogenic groups, which have pKa values of 5.60-5.70 and 6.70-6.85 respectively, were found to relate with the active site of this enzyme. The oxidation reactions were brought about by initial single electron transfer process on the active site. The enzyme was found to be a metalloprotein which had about 3.9 cupric ions per molecule of protein as a prosthetic group. The enzyme showed a strong peak at 605 nm and a weak shoulder at 330 nm in UV-Visible absorption spectrum. Both signals disappeated upon treatment of the enzyme with 4 electron equivalent ascorbate. These results indicate that type I Cu peak and type III Cu shoulder are present in laccase.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.116-121
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• 2008

In my search of microbial source of novel enzymes, a marine actinomycetes, A1460, producing haloperoxidase was isolated from macroalgae from south sea, Korea and studied for physiological and biochemical properties. The haloperoxidation reaction was followed by the bromination of phenol red in the presence of hydrogen peroxide and potassium bromide. The haloperoxidase was partially purified from the cell extract with $35\sim75%$ ammonium sulfate precipitation, High-Q anion exchange chromatography, gel filtration chromatography, hydroxyapetite chromatography and hydrophobic interaction chromatography to a yield of 42% and purification fold of 70. This enzyme showed relatively high heat stability without losing 50% of activity after 1 hr incubation at $60^{\circ}C$. The highest activity was found at $45^{\circ}C$, and the optimal pH was about pH 7, but higher stability was observed at pH 8. Azide and cyanide ion showed strong inhibition at less than 1 $\mu M$ level suggesting that the enzyme was Fe ion dependent haloperoxidase.

• Journal of Plant Biology
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• v.2 no.1
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• pp.1-12
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• 1959

1) The comparative studies of the quantitative measurement of growth characteristics and utilization of substrates by Euglena gracilis var. bacilla 10616 in the light and in darkness have been carried out. Eodogenous respiration, effect of respiratory inhibitors and responses to the added substrates for the exogenous respiration are also investigated. 2) All cultures are grown in the open air under the continuous illumination of fluorescent light of 3500 lux at room termperature, the growth rate of the culture in the basal medium added 0.5% lactate is found to be the highest. The growth rate decreases successively for the cultures of 0.5% sucinate, 0.5% Na-acetate, 0.5% malate, and control. There is no growth in the basal meidum added 0.5% butyrate and 0.5% hydroquinone. The similar results are obtained for the mentioned cultures in the darkness. However, the growth rate in basal medium added 0.5% glucose and 0.5% sucrose does seem to increase in the darkness unlike the illumination. 3) The endogenous rate of respiration for the organism cultured photosynthetically is about 12.94ul 02/mg/hr, in basal medium and the respiratory quotient is about 0.84. The rate is decreased by starvations to 6.5ul 02/mg/hr, about to a half, but the respiratory quotient does net change. 4) The oxygen consomption during initial 2 hours in suspending solution ranging from pH 4.5 to pH 9.3 is highest at pH 4.5 in which the algae had grown, at pH 5.5 and at pH 6.9. 5) Endogenous respiration of the cells is strongly inhibited by 0.1M of potassium cyanide, malomic acid, sodium fluoride and iodo-acetic acid. It is also strongly inhibited by 0.01M of potassium cyanide. 6) The respiratory response to added substrates for the exogenous respiration in the organism is coincided with the rate in the basal medium added the substrate in light and in darkness, whether the cells are fed or starved. 7) According to the results of this study, there seems to be the flexibility of the interconversion between photosynthesis and chemosynthesis, heterotropic mode of metabolism, in Euglena gracilis var. bacillaris, and that this organism utilizes the lactate most. It also may be suggested that the enayme systems linked in the each steps of Embden-Myerhof-Parnas path way and TCA cycle seem to exist in this organism.