• The Journal of Natural Sciences
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• v.5 no.1
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• pp.47-52
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• 1992

A alkalophilic, thermophilic bacterium TA-11 which produce $\beta$-galactosidase highly was isolated from compost and identified to the genus Bacillus. $\beta$-galactosidase production was maximized when it was incubated in synthetic medium containing 1.5% lactose. 0.4% peptone, 0.4% teast ext., 0.2% $MgSO_4$ 0.05% $NH_4$Cl and 0.2% NacL(initial pH; 10.0) at $50^{\circ}C$ for 2 days in reciprocal shaker.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.414-419
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• 1987

Cultural conditions for the polysaccharide production by Pseudomonas elodea ATCC 31461, a thermogellable polysaccharide producer, were investigated. Optimum condition for polysaccharide production were: temperature; $30^{\circ}C$, pH; 6.5, glucose; 25 g/L. nitrogen source; peptone, C/N ratio; 5.0. Maximum production and yield at this condition were ca. 32 g/L and 128%, viscosity of 1% polysaccharide solution was 837 mPas at 35/sec.. Consistency index and flow behaviour index were 2570 mPas and 0.66

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.212-220
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• 1987

The taxonomical properties of strain J-275L isolated from soil as a microorganism which produces extracellular adenine deaminase and cultural conditions for the enxyme production were studied. The hyphae of strain J-275L is fragmented into rod-or coccus-like elements. The elements of fragmented aerkal hyphae has smooth surfaces. The cell wall of the organism contains LL-diaminopimelic acid. Mycolic acid are not produced. As a result of taxonomical studies, strain J-275L is designated as Nocardioides sp. J-275L. The optimum medium for the enzyme production from Nocardioides sp.J-275L wascomposed of 0.5% peptone, 0.5% dextrin, 1% yeast extract, and 0.2% $K_{2}HPO_{4}$. The optimum initial pH of the medium was pH 7.5.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.389-393
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• 2002

Among the bacterial strains isolated from chungkook-jang, Bacillus subtilis CH-1, Bacills circulans K-1 and Bacillus subtitis (natto) N-1, Bacillus subtitis CH-1 showed the highest productivity of biosufactant. A-medium was selected for the basal medium in the large scale production of biosurfactant, and modified to synthetic medium which containing 2% glucose, 0.3% soy peptone, and mineral salts. The surface tension was reduced to maximal value after 96 hr after fermentation, about the 43% of initial tension. Temperature and initial pH of medium was not critical factor for the biosurfactant production. The yield of crude biosurfactant was 6 g/L under the optimum condition.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.361-366
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• 1985

Distribution and substrate specificity of 5-fluorocytosine deaminase were studied in various genera of bacteria. 5-Fluorocytosine deaminase was produced by various bacteria independent of genus and species and it catalyzed the deamination of cytosine, 5-fluorocytosine and 5-methylcytosine. Xanthomonas campestris IAM 1671 produced relatively large amount of 5-fluorocytosine deaminase. The composition of optimum culture medium for enzyme production wat glycerine 0.5％, peptone 1％, yeast extract 0.5％, NaCl 0.5％ and the initial pH of the medium was 7.5. The highest enzyme formation was observed after 24 hours of cultivation In 500$m\ell$ shaking flask containing 90$m\ell$ of medium at 3$0^{\circ}C$ on a reciprocal shaker.

• KSBB Journal
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• v.5 no.1
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• pp.25-35
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• 1990

In the Xanthan gum fermentation by Xanthomonas campestris there are problems of the large energy consumption by long fermentation time, the mass transfer of oxygen and nutrients by high viscous fermentation broth. In this study, the media optimization and the fed batch fermentation were carried out to decrease fermentation time and increase Xanthan gum yield. The $O_2$ uptake rate (OUR) and $CO_2$ evolution rate(CER) which were obtained from the analysis of fermentation exit gas using a gas chromatograph were investigated. As a result, the fermentation time decreased at optimal assimilable nitrogen concentration but increased at poor or rich assimilable nitrogen concentration, the Xanthan gum biosynthesis was stimulated under the limited condition of assimilable nitrogen source and the optimum fermentation medium was obtained as follow; Glucose=30g / l, Peptone=8.0g / l, $K_2HPO_4=2.0g/l$, $MgS0_47H_2O=10g/l$, Sodium acetate=20g/l, Sodium pyruvate=0.5g/1. As the agitation speed and nitrogen concentration increased, the $O_2$ uptake rate and $CO_2$ evolution rate increased. The OUR and CER were 37.3mmol $O_2/\;l$ hr and 20.2 mmol $CO_2/\;L$ hr at peptone 11g / l and agitation speed 990RPM, respectively. In fed batch fermentation, the final concentration of Xanthan gum was enhanced up to 29g / l.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.257-263
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• 1984

A strain producing an extracellular cytosine deaminase was isolated from soil samples. The enzyme obtained from the strain possessed the substrate specificity to both cytosine and 5-fluorocytosine. From the results of its morphological, cultural, physiological, and biochemical properties, the strain was thought to be the genus Arthrobacter. Therefore, it was named as Arthrobacter sp. JH-13. The composition of optimum medium for the enzyme formation was 0.5% of peptone, 0.5% of meat extract, 0.5% of soluble starch, and 0.1% of KCl. The optimum pH for the enzyme formation was 8.0. When the microoganism was cultured aerobically in the above medium, enzyme production reached at maximum in 54 hours at $30^{\circ}C$.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.79-82
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• 2017

An inky cap, Coprinus comatus synthesizes and secretes a laccase in the liquid yeast extract peptone dextrose medium. We have successfully purified the enzyme through the ion-exchange chromatography and the preparative gel electrophoresis. The estimated molecular weight was 67 kDa by the SDS-PAGE analysis. Optimum pH was pH 4.3 and optimum temperature was $25^{\circ}C$. The Km value was 0.45 mM and the Vmax was 0.0132 OD/min/unit for o-tolidine. Purified laccase showed 49.3% decolorizing activity against remazol brilliant blue R (RBBR) and 41.6% decolorizing activity against Poly R-478 after 12 h incubation.

• Journal of Life Science
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• v.28 no.5
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• pp.577-586
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• 2018

We recently reported the potential probiotic properties of Lactobacillus brevis SBB07 isolated from blueberries. The present study investigates the effect of culture conditions such as temperature, initial pH, culture time, and medium constituent for industrial application. The ingredients of the medium to improve cell growth were selected by Plackett-Burman design (PBD) and central composite design (CCD) within a desirable range. The PBD was applied with 19 factors: seven carbon sources, six nitrogen sources, and six microelements. Protease peptone, corn steep powder (CSP), and yeast extract were found to be significant factors for the growth of SBB07. The CCD was then applied with three variables found from the PBD at five levels, and the optimum values were decided for the three variables: protease peptone, CSP, and yeast extract. In the case of the growth of SBB07, the proposed optimal media contained 2.0% protease peptone, 2.5% CSP, and 2.0% yeast extract, and the maximum dried-cell weight was predicted to be 2.93963 g/l. By the model verification, it was confirmed that the predicted and actual results are similar. Finally, the study investigated the effects of incubation temperature and initial pH at the optimized medium. It was confirmed that the dried-cell weight increased from $2.2933{\pm}0.0601g/l$ to $3.85{\pm}0.0265g/l$ when compared to the basal medium at $37^{\circ}C$ and initial pH 8.0. Establishing the optimal culture condition for SBB07 provides good potential for applications in probiotics and can serve as the foundation for the industrialization of materials.

• Journal of Life Science
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• v.29 no.8
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• pp.861-870
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• 2019

This study was undertaken to establish optimum medium compositions for cost-effective mannitol production by Leuconostoc mesenteroides SRCM201425 isolated from kimchi. L. mesenteroides SRCM21425 from kimchi was selected for efficient mannitol production based on fructose analysis and identified by its 16S rRNA gene sequence, as well as by carbohydrate fermentation pattern analysis. To enhance mannitol production by L. mesenteroides SRCM201425, the effects of carbon, nitrogen, and mineral sources on mannitol production were first determined using Plackett-Burman design (PBD). The effects of 11 variables on mannitol production were investigated of which three variables, fructose, sucrose, and peptone, were selected. In the second step, each concentration of fructose, sucrose, and peptone was optimized using a central composite design (CCD) and response surface analysis. The predicted concentrations of fructose, sucrose, and peptone were 38.68 g/l, 30 g/l, and 39.67 g/l, respectively. The mathematical response model was reliable, with a coefficient of determination of $R^2=0.9185$. Mannitol production increased 20-fold as compared with the MRS medium, corresponding to a mannitol yield 97.46% when compared to MRS supplemented with 100 g/l of fructose in flask system. Furthermore, the production in the optimized medium was cost-effective. The findings of this study can be expected to be useful in biological production for catalytic hydrogenation causing byproduct and additional production costs.