• Journal of Microbiology and Biotechnology
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• v.21 no.9
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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.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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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.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.417-422
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• 1990

For optimal production of fructosyl transferase in AureobasidiumpuZZulane C-23, the effect of fermentation conditions for cell growth and fructosyl transferase production were investigated. Sucrose was excellent carbon source. Sucrose concentration for the optimum production of fructosyl transferase was 35%. Enzyme productivity was significantly increased by addition of ammonium oxalate and yeast extract. A time course study for the enzyme production by Aureobasidium pullutans C-23 was carried out. At 2 days incubation, the production of intracellular enzyme was maximum. The extracellular enzyme production was found to be increased up to 6 days.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.123-129
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• 1977

A potent lytic strain was selected by an extensive screening test of microorganisms isolated from soils and sewages on the medium containing baker's yeast as a carbon source. This strain (M-10) was identified to a strain of Humicola sp. by the Genera of Fungi (Clements, 1964). The strain was cultured on the basal medium composed of 2% of baker's yeast, 0.3% of $K_2HPO_4$, 0.01% of $MgSO_4{\cdot}7H_2O$, 0.1% of yeast extract in a shaking incubator. Cultural conditions for lytic enzyme production has been studied, and the results obtained were as follows: 1. The Optimal conditions for lytic enzyme production were: initial pH 5.5 to 6.0, temperature $33^{\circ}C$ in shaking culture. 2. Among the various carbon sources, baker's yeast (4%) was the best for lytic enzyme production, increasing the level of activity eight, times higher than when grown on glucose (1%). 3. The most effective concentration of $K_2HPO_4\;and\;MgSO_4{\cdot}7H_2O$ in the basal medium for lytic enzyme production was 0.1% and 0.01% respectively. 4. When the strain was cultured under the optimal conditions, the production of lytic enzyme was maximized in 72 hours.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.325-331
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• 2002

investigated to maximize the production of fibrinolytic enzyme from Fomitella fraxinea mycelia. Among the tested media, Coriolus versicolor medium (CVM) showed the highest production for the enzyme. 2% galactose, 0.6% yeast extract and 0.1% $NaNO_3$, 0.1% $K_2HPO_4$, and 0.05% $MgSO_4$.$7H_2O$ as carbon, nitrogen, phosphorus, and inorganic salt sources resulted in the maximum level of the enzyme activity, respectively. The enzyme production from F. fraxinea was reached to highest level after the cultivation for 10 days at $25^{\circ}C$ and pH 9. The enzyme activity of culture supernatant was most active at $40^{\circ}C$ and pH 10. The activity of the enzyme was inhibited by phenylmethylsulfonylfluoride and aprotinin, suggesting that it is a serine protease.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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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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• v.5 no.4
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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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• v.2 no.1
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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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• 2000.04a
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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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• 2001.11a
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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.