• The Korean Journal of Mycology
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• v.15 no.2
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• pp.99-170
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• 1987

The production and properties of laccase(E.C.1.10.3.2) from Coriolus versicolor were studied. The results were as follows; The nutritional optimum conditions for laccase production were 1% indulin At, 0.3% peptone 0.1% $KH_2PO_4$, 0.02% $MgSO_4$, 0.1 mg% $CuSO_4$.and 0.005 mg% thiamine HCI. The optimum temperature and pH of laccase production were $25^{\circ}C$ and 5.0, and respectively, and the cultural period was 20 days. The optimum pH and temperature for the activity were 4.6 and $40^{\circ}C$, respectively. The enzyme was almost stable under the temperature of $40^{\circ}C$ and within the pH range of 4.0-5.0. The enzyme was stable at $40^{\circ}C$ for 30 min. $Cu^{++}$, $Fe^{++}$ and $Ca^{++}$ activated the enzyme activity, but $Mn^{++}$ and $Hg^{++}$ were inhibited. The enzyme was totally inhibited by 1 mM sodium azide and 1 mM potassium cyanide, and partly inhibited by EDTA and hydroxyamine.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.253-261
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• 1995

A strain of alkalophilic Bacillus sp. C-21 has been Isolated from sold. The strain was capable of producing large amount of cyclodextrin glycosyltransferase (CGTase) in the high alkaline pH medium. The preferable medium composition was determined to be as follows : 1.0% soluble starch, 1.0% peptone, 0.5% yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H2O and 1.0% Na2CO3(pH 10.0) The highest enzyme production was observed after 30hours of cultivation at 33$^{\circ}C$. The optimum temperature and pH for the activity of crude enzyme were 6$0^{\circ}C$ and 6.0, respectively. The enzyme was stable between pH 6.0 and 9.6, and up to 55$^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.11
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• pp.869-875
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• 2009

The purpose of this paper is to investigate the optimal condition of the syngas production by reforming of propane using Gliding arc plasma reformer. The gliding arc plasma reformer in 3 phases has been newly designed and developed with a quick starting and fast response time. It can be applicable to the various types of fuels (Hydrocarbons $C_xH_y$), and it has a high conversion rate of fuels and high production of hydrogen. The parametric screening studies were carried out according to the changes of a steam feed amount i.e., steam/carbon ratio, total gas flow rate and input electric power. The optimum operating conditions were S/C ratio 2.8, total gas flow rate of 14 L/min and input electric power of 2.4 kW. The result of optimum operating conditions showed the 55 % $H_2$, 14 % CO, 15 % $CO_2$, 10 % $C_3H_8$ and 4 % $CH_4$. Also, $C_3H_8$ conversion, $H_2$ yield and $H_2$ selectivity were 90 %, 42 %, 15 %, respectively. The energy efficiency and specific energy requirements were 37 % and 334 kJ/mol respectively.

• KSBB Journal
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• v.19 no.4
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• pp.250-256
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• 2004

In this work we have cultivated several B. cereus strains in a complex LB medium in order to study the production of phospholipase C (PLC), and among them B. cereus 318 showed the highest productivity of PLC. Some components, i.e., 5 g/L glucose, 5 g/L yeast extract, 5 g/L peptone, 0.5∼1.0 g/L K$_2$HPO$_4$, 0.02∼0.04 g/L ZnSO$_4$$.$7H$_2$O and 3 g/L NaHCO$_3$ were found to be optimal for the high production of PLC by B. cereus 318. Optimal culture temperature and pH were found to be 30$^{\circ}C$ and pH 7.5 for the PLC production, respectively. Optimum reaction temperature and pH of the PLC produced by B. cereus 11 and 318 were 45$^{\circ}C$ and pH 4.0, while they were 50$^{\circ}C$ and pH 7.0 for the PLC by B. cereus 559. The PLC produced by B. cereus was activated by Mn$\^$2+/, Co$\^$2+/ and dimethyl sulfoxide (DMSO), but its activity was inhibited by Cu$\^$2+/ and partially by glycerol, isopropanol and sodium dodecyl sulfate (SDS).

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.231-237
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• 1995

Bacillus subtilis SH-1 have been isolated and identified from coastal sea, in Pusan, The optimal cultural characterization of Bacillus subtilis SH-1 for 속 production of bacteriolytic enzyme was determained. Bacillus subtilis SH-1 produced the bacteriolytic enzyme well in the medium consist of 1.0% glucose, 1.0% yeast extract, 1.0% NaCI, 0.02% $K_2HPO_4,\;0.002%\;MgSo_4{\cdot}7H_2O,\;0.001%\;MnSO_4{\cdot}5H_2O,\;0.0001%\;FeSO_4{\cdot}7H_2O$. The optimal medium pH, incubation temperature, and shaking tome for the highest production of the enzyme were 8.0, $30^{\circ}C$ and 28 hours respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.3
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• pp.308-310
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• 2022

Ultrawide bandgap gallium oxide (Ga₂O₃) semiconductors are known to have excellent photocatalytic properties due to their high redox potential. In this study, CO₂ reduction is demonstrated using nanostructured Ga₂O₃ photocatalyst under ultraviolet (254 nm) light source conditions. After the CO₂ reduction, C₂H₄ remained as a by-product in this work. Nanostructured Ga₂O₃ photocatalyst also showed an excellent endurance characteristic. Photogenerated electron-hole pairs boosted the CO₂ reduction to C₂H₄ via nanostructured Ga₂O₃ photocatalyst, which is attributed to the ultrawide and almost direct bandgap characteristics of the gallium oxide semiconductor. The findings in this work could expedite the realization of CO₂ reduction and a simultaneous C₂H₄ production using a low cost and high performance photocatalyst.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.58-64
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• 1997

$H_2$ production by Chromatium sp., a large purple sulfur bacterium blooming in lake Kaiike, under various environmental conditions was examined. Chromatium sp. produced $H_2$ only in the presence of light and $H_2$. Maximum $H_2$ production ($0.01\;{\mu}mol/hr/(mg\;dry\;cell\;weight)$) was obtained in the solution of 20 mg $H_2S-S/l$ under low light intensity (1000 lux) at $30^{\circ}C$. $H_2$ production was severely inhibited by the presence of $N_2\;or\;NH_4^+$. The rate observed for Chromatium sp. was relatively low compared to that of other phototrophic bacteria. Chromatium sp. is probably a most potent Ha producing species in lake Kaiike, since the bacterium readily produced $H_2$ photoautotrophically even at low light intensities by the application of suboptimal $H_2$ concentrations. Based on the photoautotrophic characteristics of bacterial $H_2$ production, it is suggested that Chromatium sp. can be an economic and practical species for biological $H_2$ production system, particularly in temperate region.

• Journal of Life Science
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• v.12 no.5
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• pp.570-576
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• 2002

The extremely halophilic archaebacterium Haloarcular sp. EH-1 was isolated from solar salts. Amylae production from Halonrcular sp. EH-1 have been studied. The results obtained were as follows. The optimal medium composition for the production of amylase from Haloarcular sp. EH-1 were soluble starch 1.5%, yeast extract 1.0%, MgSO$_4$ 7h$_2$O 2.0%, KCI 0.1%, NaCl 25% (pH 7.5). The incubation temperature, aeration rate and agitation speed were 4$0^{\circ}C$, 100 $m\ell$ medium / 500 $m\ell$ shaking flask, and 110 rpm. The cell growth and enzymatic activity was highest at 9 days of incubation. So amylase production appeared to be a growth-related phenomenon.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.199-202
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• 2000

Optimization of submerged culture conditions for the production of exo-biopolymer from Paecilomyces japonica was studied. Maltose, yeast extract and potassium phosphate were the most suitable sources of carbon, nitrogen, and inorganic salt, respectively, for both production of the exo-biopolymer and mycelial growth. The optimal culture conditions in flask culture were pH 5.0, $25^{\circ}C$ and 150 rpm in a meidum containing of 30 g maltose, 6 g yeast extract, 2 g polypeptone, 0.5 g $K_2HPO_4$, 0.2 g $KH_2PO_4$, 0.2 g $MnSo_4\;{\cdot}\;5H_2O$, 0.2 g $MgSO_4\;{\cdot}\;7H_2O$ in 1-L distilled water. Exo-biopolymer production and mycelial growth in the suggested medium were significantly increased in a 2.5-L jar fermentor, where the maximum biopolymer concentration was 8 g/1.

• Microbiology and Biotechnology Letters
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• v.29 no.4
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• pp.221-226
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• 2001

Streptomyces themocyaneovio-laceus producing the thermostable xylanase was used for the production of xylooligosaccharides from xylan. The optimal conditions for the xylanase production were investigated in jar fermentor, which operated at 2 vvm aera-tion and 400 rpm agitation speed at $50^{\circ}C$ for 24 h. The optimal reaction condtion for the production of xylooli-gosaccharides with xylanases which were prepared by the percipitation with ammonium sulfate were obtained by the reaction at $60^{\circ}C$ for 12 h in the mixture composed of 10% birchwood xylan in 50 mM sodium phosphate buffer (pH 6.0)and 10 unit/ml of xylanase. In this optimal condition for the xylooligosaccharides production the mixture of xylooligosaccharides (58.8 g/I) which were composed of 20.1 g/I of xyobiose, 8.9 g/I of xylotriose 4.5 g/I of xylotetraose 16.2g/I of xylopentaose and 9.1 g/I xylohexaose and 5.0 g/I of xylose was produced from 100 g/I of birchwood xylan by the xylanases of S thermocyaneoviolaceus .