• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.430-433
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• 2001

Erinacine which is produced from Hericium erinaceus mycelia is known as stimulating activity of nerve growth factor(NGF) synthesis. Thus. this work was concentrated on the maximum production of Hericium erinaceus mycelia. Media compositions were studied as the chemical conditions that affected cell growth. The modified media was ditermined from the results, including glucose 20g/L and yeast extract 10g/L.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.749-755
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• 1996

From the soil collected from provincial area of South Korea, a microorganisms which have been shown good growth in the minimal poultry feces extract medium was isolated. Supplement of glucose to the poultry feces extract medium helped the complete uptake of soluble protein by microorganism. Uric acid in the poultry feces extract medium could be completely degraded during the microbial growth. Maximum cell growth (3.8 $\times$ 10$^{9}$ CFU/ml) obtained at 36 hours of incubation after inoculation. Uric acid was degraded faster in minimal medium than in the glucose complement medium. VFA (volatile fatty acid), which are known as major compounds of poultry feces odor, were almost removed from the minimal poultry feces extract medium. Glucose supplement to the minimal medium enhanced the growth of microbial cells. Addition of 4% of glucose and 4% of neopeptone to the minimal poultry feces extract medium helped the maximal growth of cells.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.447-450
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• 2000

Microorganism, including some bacteria isolated from soil, were found to secrete an extracellular soymilk-clotting enzyme. Using this bacterial enzyme experiments were carried out to optimize the hydrolyzing conditions for the production of soy peptides. The soy peptides produced by hydrolyzing 11S globulin with enzyme treatment at $65^{\circ}C$, pH 6.1, for 1hr were found to have a accessible possibility. The obtained coagulum by enzymatic reaction was very flocculation with fine structural formation. Properties of peptide Y and W of the enzyme hydrolysates at pH 6.1 were superior to that of isoelectric precipitation because these peptides were miscible with water in all proportions.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.04a
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• pp.114.2-115
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• 1979

Horikoshi등이 호 alkali 성 미생물에 관한 연구에서 분리한 수종의 cellulolytic bacteria중에서 가장 강력한 균체의 효소를 생산하는 Aeromonas 속 세균의 cellulolytic 효소에 관한 연구 결과를 보고한다. 공업적으로 생산된 효소를 사용하여 효소작용의 최적조건을 측정하고 gel filtration, ion-exchange chromatography 및 affinity chromatography 로 cel-luplytic 효소를 분리정제하였다. 본 효소의 활성 최적 pH는 7.0~8.5로 alkaline 효소였으며 반응온도 5$0^{\circ}C$에서 가장 강한 활성을 보였다. 분리 정제과정에서 carboxymethyl cellulose (CMC)에 대하여 활성이 있는 단백질이 최소 8종이상 분리되었으며 이중 1개 효소는 CMC에 대해서는 극히 낮은 활성을 보였으나 결정성 기질인 Avicel 에는 강한 활성을 보였다. 본 연구의 결과를 Cellulomonas속 세균 및 Trichoderma속 곰팡이의 효소와 그 성질을 비교 검토하였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.224-225
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• 2001

$\delta$-Aminolievulinic acid (ALA)는 대부분의 생물에 필수적인 tetrapyroll 화합물의 생합성 전구체로 최근 들어 다양한 의학적 용도 (피부암 치료제, 화상치료제, 면역증 강제 등)가 밝혀짐에 따라 이의 생산 및 사용범위에 대한 연구가 활발히 진행되고 있다 (Elfsson, 1998). 또한 양식어의 사육시 그 피해가 심각한 바이러스(이리도바이러스, 버나바이러스, 및 새우의 백점바이러스 등)와 원생충에 의한 감염성질병에 대하여 탁월한 예방 및 치료 효과를 나타내었으며, 저 농도의 경구투여에 의하여 항바이러스성 및 면역활성 유발 기능이 확인되어지는 등, 질병 관리를 위한 새로운 기능이 확인되었다. (중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5179-5186
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• 2012

Miglitol, a well-known therapeutic intervention agents for diabetes, exhibits competitive inhibitory activity against ${\alpha}$-glucosidase and it is usually produced through three sequential steps including chemical and bioconversion processes. Gluconobactor oxydans (G. oxydans) belonging to acetic acid bacteria biologically, converts 1-deoxy-1-(2-hydroxyethylamino)-D-glucitol (P1) into a key intermidiate, 6-(2-hydroxyetyl) amino-6-deoxy-${\alpha}$-L-sorbofuranose (P2) by incomplete oxidation. In this study, we identified and optimized fermentation conditions of CK-2165, that was selected in soil samples by comparing the bioconversion yield. CK-2165 strain was found to be closely related to G. oxydans based on the result of phylogenetic analysis using 16S rDNA sequence. Utilization of API 20 kits revealed that this strain could use glucose, mannose, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin and arabinose as carbon sources. The culture conditions were optimized for industrial production and several important factors affecting bioconversion rate were also tested using mycelial cake. Cell harvested at the late-stationary phase showed the highest bioconversion yield and $MgSO_4$ was critically required for the catalytic activity.

• KSBB Journal
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• v.16 no.5
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• pp.516-522
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• 2001

The large-scale production of antibiotics by filamentous mycelial organism requires and adequate supply of dissolved oxygen. In terms of productivity, it means that oxygen transfer is the rate-limiting step. Therefore, the oxygen transfer coefficients(K$\_$L/A) were determined in a broth involving a filamentous mycelial organism such as Streptomyces avermitilis for use in fermentations. To determine (K$\_$L/A) inn a stirred vessel, a great deal of effort is required to provide all the cells with a sufficient oxygen supply. To overcome the oxygen limitation in a batch culture, a fed-batch culture was applied to control the growth rate by an intermittent supply of nutrients. Thus, it was possible to maintain a suitable dissolved oxygen concentration at a low agitation rate. The optimal agitation speed was 350 rpm at low cell concentrations (below 7 g/L) by considering the efficiency of agitation and shear stress. The (K$\_$L/A) was found to decrease from 64.26 to 29.21h.$\^$-1/ when the biomass concentration was increased from 9.82 to 12.06 g/L. In addition, and increase in viscosity was also observed during the growth phase. By comparing the (K$\_$L/A) values for the various agitation and aeration rates, it was found that the effect of an increase in (K$\_$L/A) by aeration was reduced dramatically at high biomass concentrations. However, this effect was not observed when altering the agitation rate. This suggests that controlling the dissolved oxygen concentration by altering the agitation rate was more efficient than increase the aeration rate.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.55-59
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• 2006

This study was designed to investigate the optimum manufacturing condition of germanium-fortified yeast, and the binding properties of germanium (Ge) in germanium-fortified yeast. The nutritional optimum conditions were glucose 3.0 (w/v) %, yeast extracts 0.3 (w/v) % and peptone 0.5 (w/v) %, and the amounts of yeast cells were 67.4 mg/ml. And, the standard germanium-fortified yeast was produced under the condition at the ratio of yeast cell and germanium solution was 1 : 0.5 (50%), pH 6.5 and $35-40^{\circ}C$ during fermentation. In results of the identification, binding of germanium-protein showed structural difference between the inorganic Ge $(GeO_2)$ added during fermentation process and germanium-fortified yeast. Therefore, germanium-fortified yeast made by biosynthetic technology formed structurally safe organic germanium during fermentation process. Germanium-fortified yeast can be applied as a new functional material far the improvement of health, the prevention and treatment of chronic degenerative disease like cancer, and the enforcement of immune system.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.568-573
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• 1989

As a way to determine the optimal culture conditions for the production of ${\gamma}$-linolenic acid by Mucor sp. KCTC 8405P, the influence of different carbon and nitrogen sources, initial pH, and C/N ratio of medium was investigated. Glucose was found to be the best carbon source in terms of lipid content and ${\gamma}$-linolenic acid yield. Ammonium sulfate and organic nitrogen sources such as urea and peptone resulted in relatively increased lipid and ${\gamma}$-linolenic acid production. The highest accumulation of lipid was obtained at a C/N ratio of 56.6 using glucose and (NH$_4$)$_2$SO$_4$ as carbon and nitrogen source, respectively. It was found that the lipid content increased significantly with increasing initial pH of medium up to pH 9.0. The influence of mixed carbon source on the ${\gamma}$-linolenic acid yield was also investigated. High accumulation of lipids, 315 mg/100 ml medium, and 13-14% of ${\gamma}$-linolenic acid content in the cellular lipid were obtained in a shaking culture containing 3% of glucose and 2% sodium acetate as carbon source and 0.1% of (NH$_4$)$_2$SO$_4$ as nitrogen source at pH 8.0.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.227-232
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• 1976

This experiment was carried out to investigate the effects of red pepper powder on its enzyme production and growth of Aspergillus oryzae. In this report, Aspergillus oryzae A and G strains were cultured to the wheat bran and Czap다 Dox liquid media containing red pepper powder. And their enzyme activity. dry mycelial weight, pH and acidity were determined respectively. The results obtained were as follows. 1. In the case of protease reaction on the substrate without salt, the addition of red pepper powder ranging from 0.05 to 30 per cent to the wheat bran medium showed the increased neutral and alkali protease production in comparison with the control. However, the acid protease production were decreased by the addition of red pepper powder in the case of Aspergillus oryzae G strain. 2. In the case of protease reaction on the substrate with 10 per cent of salt, wheat bran medium containing 0.05 to 10per cent of red pepper powder showed the high protease production in comparison with the control. 5. As the amount of red pepper added to the Czapek-Dox lipuid culture was increased, the dry mycelial weight produced by Aspergillus oryzae A and G strains were also increased. And the dry mycelial weight produced by Aspergillus oryzae A strain was much more than that of Aspergillus oryzae G strain. 6. The addition of red pepper powder brought the fall of pH in Czapek-Dox liquid medium. 7. By the increase of red pepper powder concentration, the acidity in Czapek-Dox liquid culture were increased. And the increase ratio in the case of Aspergillus oryzae G strain was more remarkable than that of Aspergillus oryzae A strain.