• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.947-953
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• 2011

A fungal strain, Aspergillus terreus strain GA2, isolated from an agricultural field cultivating sweet sorghum, produced feruloyl esterase using maize bran. In order to obtain maximum yields of feruloyl esterase, the solid state fermentation (SSF) conditions for enzyme production were standardized. Effective feruloyl esterase production was observed with maize bran as substrate followed by wheat bran, coconut husk, and rice husk among the tested agro-waste crop residues. Optimum particle size of 0.71-0.3 mm and moisture content of 80% favored enzyme production. Moreover, optimum feruloyl esterase production was observed at pH 6.0 and a temperature of $30^{\circ}C$. Supplementation of potato starch (0.6%) as the carbon source and casein (1%) as the nitrogen source favored enzyme production. Furthermore, the culture produced the enzyme after 7 days of incubation when the C:N ratio was 5. Optimization of the SSF conditions revealed that maximum enzyme activity (1,162 U/gds) was observed after 7 days in a production medium of 80% moisture content and pH 6.0 containing 16 g maize bran [25% (w/v)] of particle size of 0.71-0.3 mm, 0.6% potato starch, 3.0% casein, and 64 ml of formulated basal salt solution. Overall, the enzyme production was enhanced by 3.2-fold as compared with un-optimized conditions.

• 한국식품영양학회지
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• 제25권4호
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• pp.1055-1060
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• 2012

In order to produce Hongkuk-ju, the production and characterization of Hongkuk (Monascus red koji) by Monascus anka KCTC 6121 were investigated. The optimum cultural conditions for the production of enzyme (${\alpha}$-amylase and glucoamylase) and pigment (yellow and red) from this strain on solid culture (steamed rice) were examined. The results showed that the production of ${\alpha}$-amylase and glucoamylase reached the highest for 9 days and 8 days, respectively. Since then, the productions decreased slightly. The production of yellow and red pigments reached the highest for 8 days, decreasing slightly soon after. The optimal content of the initial moisture equally presented 30% in the enzyme and pigment production. After that, the enzyme production decreased slowly, whereas pigment production decreased sharply. The optimal temperature of the culture also showed $30^{\circ}C$ in the production of enzyme and pigment. It was found that the initial inoculum size in enzyme and pigment production was 10% and 20%, respectively. Under these optimal conditions, the production of monacolin K and citrinin was 74.35 mg/kg and 5 mg/kg for 12 days, respectively.

• 한국미생물·생명공학회지
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• 제18권4호
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• pp.417-422
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• 1990

선발균의 효소생산성 향상을 위해 배양과정의 특징을 조사하였다. 효소생산을 위한 최적의 탄소원은 sucrose (35)이고, 질소원은 ammonium oxalate와 yeast extract를 함께 넣어 주었을 때이었다. 5l jar fermentor에서 선발균의 배양형태를 조사한 결과 2-3일 배양기간에는 pH가 4 이하로 현저하게 감소하는 것을 관찰하였고 4일 이후 다시 pH가 5-6 사이로 증가하였다. 균의 성장은 4일까지 증가하였다. 균체내 효소의 생성은 2일까지는 현저한 증가를 보이고 3-4일 정도 큰 변화를 나타내지 않으며 5일 이후 감소하였다. 균체외 효소는 5-6 일까지 계속 증가하는 형태를 나타내었다. Glucose로 24시간 동안 미리 배양한 후 surcose를 첨가하여 배양했을 때 균체내 효소의 생산이 현저히 증가하는 것을 알 수 있었다.

• Applied Biological Chemistry
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• 제20권1호
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• pp.123-129
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• 1977

효모세포벽 분해효소를 생산하는 386주(株)의 미생물을 분리하여 그중 강한 1주(株)를 선발 동정(同定)하고 선정균의 효소생산조건을 검토하여 다음과 같은 결과를 얻었다. 1. 선정한 M-10 strain은 Humicola sp.로 동정(同定) 되었다. 2. 선정균의 효소생성은 pH 6.0 $33^{\circ}C$에서 가장 양호하였다. 3. 탄소원으로서 baker's yeast 4%가 Iytic enzyme 생산에 가장좋았고 기타 laminarin과 dextrin 등이 효과적이었으며 질소원도 peptone이 다소 효과적이나 baker's yeast로서 족하였다. 4. 효소생산에 $K_2HPO_4$ 0.1%와 $MgSO_4{\cdot}7H_2O$ 0.01%의 첨가가 가장 효과적이고 기타 염류의 첨가는 효과가 없었다. 5. 선정한 배지조성에서 72시간 진탕배양으로 최고에 달하였다.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.325-331
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• 2002

아카시재목 버섯 균사체로부터 혈전용해효소를 생산하기 위한 최적 배양조건을 조사하였다. 복합배지 중 CVM이 가장 우수하였으며, 탄소원, 질소원, 인산원 및 무기질원으로 각각 2% galactose, 0.6% yeast extract와 0.1% $NaNO_3$, 0 0.1 % $K_2HPO_4$, 및 0.05% $MgSO_4$. $7H_2O$의 첨가에 의하여 효소의 활성이 가장 증가하였다. 따라서 F. fraxinea로부터 혈전용해효소를 생산하기 위한 최적 배지조건은 2% galactose, 0.6% yeast extract, 0.1 % $NaNO_3$, 0.1 % $K_2HPO_4$ 및 0.05% $MgSO_4$. $7H_2O$이다. 이상의 배지를 사용하여 배양온도 $25^{\circ}C$ 초기 pH 9에서 10일 동안 배양하였을 때 효소의 생산이 가장 높은 결과를 나타내었다. 배양액 중의 효소의 최적 온도 및 pH는 $40^{\circ}C$ 및 pH 10이었다. 본 효소의 활성이 PMSF와 aprotinin에 의하여 완전히 억제되는 것으로 보아 본 효소가 senne protease 계열의 효소임을 추정할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.666-674
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• 2009

An electrochemical bioreactor (ECB) composed of a cathode compartment and an air anode was used in this study to characterize the ethanol fermentation of Zymomonas mobilis. The cathode and air anode were constructed of modified graphite felt with neutral red (NR) and a modified porous carbon plate with cellulose acetate and porous ceramic membrane, respectively. The air anode operates as a catalyst to generate protons and electrons from water. The growth and ethanol production of Z. mobilis were 50% higher in the ECB than were observed under anoxic nitrogen conditions. Ethanol production by growing cells and the crude enzyme of Z. mobilis were significantly lower under aerobic conditions than under other conditions. The growing cells and crude enzyme of Z. mobilis did not catalyze ethanol production from pyruvate and acetaldehyde. The membrane fraction of crude enzyme catalyzed ethanol production from glucose, but the soluble fraction did not. NADH was oxidized to $NAD^+$in association with $H_2O_2$reduction, via the catalysis of crude enzyme. Our results suggested that NADH/$NAD^+$balance may be a critical factor for ethanol production from glucose in the metabolism of Z. mobilis, and that the metabolic activity of both growing cells and crude enzyme for ethanol fermentation may be induced in the presence of glucose.

• Preventive Nutrition and Food Science
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• 제5권4호
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• pp.194-196
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• 2000

A bacterium capable of producing polygalacturonase was isolated from kimchi, and identified as a strain of Bacillus. The effects of culture conditions and medium composition on enzyme production were investigated. Among the tested carbon sources, polygalacturonic acid or pectin was most effective for the production of the enzyme. Therefore, it seemed that the enzyme was induced when pectin or polygalacturonic acid was used as a sole source of carbon. The optimal concentration of polygalacturonic acid was 0.5%. For nitrogen sources, yeast extract was best for the production of the enzyme, at a level of 0.25%. The enzyme was maximally produced by cultivating the isolated Bacillus sp. at an initial pH of 88.0 and temperature of 45$^{\circ}C$ for 20 hours.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.105-111
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• 1999

In order to produce functional chitin oligosaccharides, a chitinolytic bacterium was newly screened from the viscera of Korean bony fishes, and identified as Bacillus sp. LJ-25. For the production of chitinolytic enzymes, $1.0\%$ nutrient broth and $0.3\%$ colloidal chitin were used as nitrogen and carbon source, respectively. The optimal temperature, initial pH and concentration of NaCl for the enzyme production by Bacillus sp. LJ-25 were $30^{\circ}C$ 6.5-7.0 and $1.0\%$, respectively. The enzyme activity of Bacillus sp. LJ-25 increased until the incubation time of 168 hr, followed by a decrease in activity.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.57-58
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• 2000

Production of dye-decolorizing enzyme was investigated with the cultivation of Geotrichum candidum Dec1 (abbreviated to Dec1) using molasses as a cheap raw materials. Molasses was found to stimulate the enzyme production as well as a role of carbon source, because the production increased with molasses content up to 50 g/L. However, the severe inhibition of dye-decolorizing enzyme activity was observed even at low concentration of molasses 10 g/L when purified decolorizing peroxidase was used. Its inhibitory effect was reduced through the cultivation of Dec1. The fractions of molasses separated by a gel chromatography showed the different degrees of inhibition. As a way to reduce the inhibitory effect, the dilution of culture broth was examined, and the total decolorizing activity for Reactive blue 5 increased 7 times as much as that of original culture broth by 30 times dilution. On the basis of result, we proposed a process scheme which can fully utilize both positive and negative effect of molasses in dye-decolorizing process using molasses.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.640-641
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• 2001

The mycelium of 3 edible mushrooms, Shizophyllum commune, pleurotus ostreatus, Tricholoma sp. was cultured in a liquid for the production of a fibrinolytic enzyme. Among them, Shizophyllum commune produced highest amount of the enzyme. The intramycelial production of the fibrinolytic enzyme by the culture of the Shizophyllum commune mycelium was approximately 6-fold higher than the extramycelial production. The carbon and nitrogen sources for the production of the enzyme were 1.5% corn steep liguor and 1.0% soytone, respectively, and optimal culture temperature and initial pH were $25^{\circ}C$ and pH 6, respectively.