• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.53-60
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• 1984

The followings are the results obtained from the investigation of isolation and cultural conditions of a fungus producing antibiotic from humus, spring soil, paddy, field and etc. 1. Among fungi which were capable of antimicrobial sub stance producing at the $45^{\circ}C$, Strain H-3 was selected as test st rain because of its efficiency in antimicrobial substance producing. 2. Strain H-3 was identified as a Aspergullus fumigatus by the mophological properties. 3. The compositions of optimun media for the production of antimicrobial substance were followed;glucose 20g, $NaNO_3$ 3g, $K_2HPO_4$ 1g, $CaCl_2$ 0.5g, $MgSo_4$ 0.5g, $FeSO_4$ 0.005g. 4. Optimum culture conditions were founded to be pH 5.0, $40^{\circ}C$ respectively. 5. The maximum antimicrobial substance producing obtained in this study was showed 14mm of clear zone after 72 hrs incubation under the optimum conditions. 6. AF-c substance was active against Gram-positive, Gram-negative bacteria, and yeast but not mold in its biological properties.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.22-26
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• 2004

The ligninolytic basidiomycete, Pleurotus ostreatus K-2946, was produced a manganese peroxidase (MnP) activity when grown in liquid culture with glucose-yeast-peptone (G-Y-P) medium. However, lignin peroxidase (LiP) was not detected in this culture medium. The purification progress of MnP was purified that included chromatography on Sepharose CL-6B, Superdex 75 prep grade and Mono-Q. MnP purified by column chromatography, was 36400 dalton and a pI of 3.95. The optimal pH and temperature of the purified MnP activity were 5.0 and $55^{\circ}C$. The characteristics of MnP produced was quite similar to those of MnP 3 isoenzyme produced by other strains of P. ostreatus.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.489-495
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• 1998

The optimum culture condition of Scopulariopsis brevicaulis for the production of ${\alpha}$-galactosidase was as follows: Tryptone 1.5%, $NH_4NO_3$ 0.2%, Raffinose 2.5%, $KH_2PO_4$ 0.5%, yeast extract 0.5%, pH 7.0, $27^{\circ}C$. The optimum pH and temperature for the enzyme activity of ${\alpha}$-galactosidase producing Scopulariopsis brevicaulis were pH 7.0 and $27^{\circ}C$, respectively. The enzyme was relatively stable at $pH\;6.0{\sim}8.0$ and at temperature below $40^{\circ}C$. The activity of the enzyme was inhibited by $Ag^{2+},\;Hg^{2+},\;Cu^{2+}$, p-chloromercuribenzoic acid and Iodine. These results would indicate the presence of -SH groups in the catalytic site of the enzyme. Km value was 1.9 mM for $p-nitrophenyl-{\alpha}-D-galactopyranoside$ and Vmax value was $9.66{\times}10^2\;{\mu}M/min$. Sugar constituents of culture broth were identified by HPLC that the enzyme liberated sucrose, glucose and fructose from raffinose and raffinose was significantly decreased.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.156-162
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• 1988

Optimal conditions for the formation and regeneration of protoplasts of the cellulolytic fungus Penicillium verruculosum were investigated. Among the various commercial cell wall lytic enzymes tested, 0.5%(w/ v) Novozym 234 was the most effective for protoplast formation. The highest yield of protoplast exceeding 4.5$\times$10$^6$/m$\ell$ obtained when 400mg of 20 hr-old mycelia was incubated with 0.5%(w/v) Novozym 234 at 3$0^{\circ}C$ for 1 hr. The best osmotic stabilizer for the isolation and re-generation of protoplasts was 0.7M sorbital (pH 5.6) and 0.6M MgSO$_4$(pH 5.6), respectively. When 0.6M MgSO$_4$was added as osmotic stabilizer to the complete medium, the maximum regeneration frequency obtained was 4.6-27.8%. Micromorphological change of giant protoplasts into hyphae was observed during incubation in the regeneration liquid medium.

• KSBB Journal
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• v.14 no.1
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• pp.71-75
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• 1999

A highly effective phosphorus accumulating bacterium named Acinetobacter CW3 was isolated from the nature by using Winogradsky columns. The optimal cultivation conditions of Acinetobacter CW3 in shaking flask were determined as $20^{\circ}C$, pH 7, 200rpm, 18.5mg $PO_4$-P/L. Acientobacter CW3 could remove phosphorus completely in 12hours for a batch culture at optimal cultivation condition. This bacterium could uptake phosphorus on aerobic condition and release it on anaerobic condition.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.219-225
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• 1988

Two isozymes of cellobiohydrolase and fifteen isozymes of endoglucanase from Trichodema viride QM 9414 were purified by ammonium sulfate fractionation, Sephadex G-100 column chromatography, DEAE-Sephadex A-50 column chromatography and preparative electrophoresis. The purified cellobiohydrolnse had a molecular weight of 71,000 estimated by electrophoresis and amino acid analysis showed its main amino acids to be in the form of aspartic acid and glutamic acid result-ing from its low pI point of 3.81. The optimum pH and temperature were 5.1 and 5$0^{\circ}C$ respectively.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1307-1318
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• 2000

The purpose of this study is to investigate the degradation characteristics of oxalic acid and citric acid by $UV/H_2O_2$ oxidation. For this purpose, the effects of pH, $H_2O_2$ dosage and the concentration of each compounds on the degradation of oxalic acid and citric acid by $UV/H_2O_2$ were investigated. Oxalic acid was effectively degraded at the wavelength of 254 nm, while the degradation efficiency of citric acid was very low at the same wavelength. It was also found that both organic substances were not degraded by the injection of $H_2O_2$ only. The optimum pH of degradation of oxalic acid and citric acid was 4 and 4 to 6, respectively. In the case of $UV/H_2O_2$ oxidation, the degradation efficiency was increased by increasing $H_2O_2$ dosage. The degradation efficiency decreased when the dose of $H_2O_2$ exceeds 200 mg/L. From these results, it can be concluded that the optimum reaction conditions for the degradation of oxalic acid and citric acid by $UV/H_2O_2$ oxidation were pH 4 and 200mg/L of $H_2O_2$.

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.177-186
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• 2005

미래의 친환경 에너지인 수소에너지 생산을 위해서 생물학적인 수소생산방법에 관한 관심이 증폭되고 있다. 생물학적인 수소생산 방법에는 여러 가지가 있으나 그중 유기물을 혐기발효하여 수소를 생산하는 방법에 관한 연구가 수행되었다. 본 연구에서 혐기성 미생물인 Enterobacter asburiae SNU-1이 쓰레기 매립지 토양에서 분리되어 수소생산 조건의 최적화 실험을 수행하였다. 본 실험에 이용된 미생물의 경우는 기존에 연구 된 적이 없는 새로운 종으로써 다른 미생물과는 다른 특징을 나타내며 수소생산 능력도 뛰어난 것을 알 수 있었다. 미생물을 이용한 수소생산에 영향을 미치는 인자로는 pH, initial glucose concentration 등이 있으며 각각의 조건에서 수소생산량을 비교하였다. 실험 결과 strain SNU-1의 최적 pH는 7이었으며 최적 initial glucose concentration은 25 g/1이다 이와 같은 최적 조건에서 strain SNU-1은 6.87 mmol/l/hr의 productivity를 나타내었다. 또한 다른 미생물과 달리 미생물이 더 이상 자라지 않는 정지기에서 더 많은 수소생산량을 나타내는 특이한 거동을 보이는 것이 관찰되었다.

• Korean Journal of Food Science and Technology
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• v.12 no.1
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• pp.1-5
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• 1980

Crude invertase was obtained from the water extracts of Korean ginseng, Panax ginseng C. A. Meyer, by fractionation with $0.8{\sim}1.0$ saturation of ammonium sulfate. The properties of the crude invertase were as follows: Crude invertase was stable in the pH range between 5 and 9, and at the temperature below $35^{\circ}C$. Crude invertase showed the optimum pH at 5.0 and the optimum temperature at $50^{\circ}C$. The activity of the crude invertase was inhibited by $Ag^{+}\;Mn^{+}\;Hg^{+}\;Zn^{+},\;and\;Rb^{+}$, while $Ca^{+}\;Cu^{+},\;and\;Fe^{3+}$ demonstrated remarkable increasing effects on the enzyme activity.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.90-96
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• 1998

The purpose of this study is to investigate the liquid culture conditions for mass production of Metarhizium anisopliae var. majus ARS 978 which is a potential microbiological pesticide. The temperature and pH range for optimal cultivation were $28^{\circ}C$ and pH 7.0, respectively. For M. anisopliae ARS 978, 1.0 %(v/v) molasses, 1.0 %(w/v) distiller's dry solubles, and 0.3 %(w/v) $CaCO_{3}$ were found to be the proper nutrients, considering cell mass, enzyme activities and spore concentration.