• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.157-162
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• 1999

Bacillus pumilus PJ19 isolated from Pinus leaves showed optimum xylanase production when grown in yeast tryptone broth at $37^{\circ}C$, pH 7.2, and shaken at 200 rpm after 48 h of incubation. Xylanase production was induced by xylan and xylose but repressed in the presence of glucose. Xylanase production by B. pumilus PJ19 was not growth-associated and the maximum enzyme production was found after 36 h of incubation.

• KSBB Journal
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• v.15 no.6
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• pp.584-588
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• 2000

The optimum conditions for the production of an antifungal antibiotic from Bacillus sp. YJ-63 were investigated. The oprimumized medium consisted of 1.5% soluble starch, 1% tryptone and 0.5% yeast extract, and temperature and initial medium pH for production were optimal at 35$^{\circ}C$ and pH 6.0, respectively. Production yield was significantly improved by shaking culture using 50 ml medium in 500 ml flasks. Under these conditions, the production of the antifungal antibiotic was growth-dependent, from 35hrs into cultivation to the stationary phase and endospore formation.

• Journal of Life Science
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• v.22 no.4
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• pp.472-477
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• 2012

A thermophilic $Alicyclobacillus$ $acidocaldarius$, which produces thermostable ${\alpha}$-amylase, was isolated from the hot water effluent of a boiled rice mill near Tirupati, Andhra Pradesh, India. The effect of different culture conditions on the growth and production of extracellular ${\alpha}$-amylase by thermophilic $A.$ $acidocaldarius$ was investigated in laboratory scale. The results showed that the optimum conditions for the production of ${\alpha}$-amylase are a temperature of $60^{\circ}C$, pH of 6.0, and medium starch concentration of 1.0%, and yeast extract and tryptone of 0.2%. Surfactants, like Tween-20 and SDS, up to 0.02%, were found to increase the bacterial growth and enzymes. Further increase in their concentration resulted in significantly decreased enzyme production.

• Journal of Applied Biological Chemistry
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• v.58 no.1
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• pp.81-88
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• 2015

To characterize the culture medium for the biosurfactant production by Bacillus pumilus IJ-1, the influences of various carbon, nitrogen and mineral sources were assessed. As a result, the highest biosurfactant production was observed after 96 h cultivation containing 0.5% (w/v) tryptone. The strain was able to grow and produce biosurfactant at 0-10% (w/v) NaCl, in the pH range of 5-10, and at $20-45^{\circ}C$. Optimal culture conditions for the biosurfactant production were at $20^{\circ}C$ and pH 9.0 after 72 h incubation and the surface tension of biosurfactant was 27.0 dyne/cm.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.1-5
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• 2002

Cultural characteristics of Cordyceps militaris preserved in EFCC, Kangwon National University were investigated for the mass production. The higher mycelial density of C. militaris was observed in Sabouraud's yeast and Yeast Malt agars, but the higher mycelial growth in Mushroom Minimal agar than other agars. The mycelium of C. militaris was observed to grow well at $25^{\circ}C$ and pH 6.0 respectively. The dextrose was found the best suitable energy source among the carbohydrates used for its mycelial growth, while the fructose or lactose observed to be well for mycelial growth. Hemoglobin was observed to be the best among the protein sources used for mycelial growth, while tryptone found to be the best in the spore formation. Similarly, the mycelial growth was best in mineral salts of $KH_2PO_4$ or $K_2HPO_4$ and the optimum C/N ratio was 100 : 1.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.162-168
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• 2001

For lactic acid fermentation of chestnut broth,10 strains of bacteria were isolated from human feces and commercial yogurt,6 of which were identified to be Bifidobacterium and the rest isolated from Acidities of the chestnut broths fermented by these strains were lower than yogurt, but more than two times higher than yogurts made from seeds or vegetables including soy milk. To stimulate acidity of the fermented broths, addition of yeast extract and tryptone peptone were the most effective at the concentration of 0.2 and 0.4%, respectively, while glucose addition above 0.5% up to 8% did not increased the acid production except a few strains of Lactoba- Cillus. Among the tested fruits and vegetables, carrot juice supplementation was the most effective in acid produc- tion by most of the tested strains. Saccharification of chestnut broth by hydrolyzing process greatly increased the acid production at 25% of cooked chestnut. However, compared to the results from the 8% of unhydrolyzed chest- nut, the net increase in acid production by hydrolysis was not much stimulative.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.599-606
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• 1990

A chitinase-producing bacterium, Aeromonas salmonicida YA7-625, was isolated from domestic seashore muds. The preferable medium composition for the production of chitinase was as follows: colloidal chitin 1.26% (w/v), tryptone 2.95% (w/v), $MgSO_4-7H_20$ 0.15% (w/v) and $K_2HP0_4$, 0.15% (w/v) (pH 8.5). The highest enzyme production was observed after cultivation of 48 hours at 27OC. The chitinase of Aeromonas salmonicida YA7-625 was purified successively by ammonium sulfate precipitation, affinity adsorption, hydroxylapatite column chromatography and gel filtration. The optimal temperature and pH for the activity of purified chitinase were $50^{\circ}C$ and 7.0, respectively. The molecular weight of purified chitinase was ca. 200,000 daltons and apparent Km value of it was 1.276 mglml on colloidal chitin.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.450-459
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• 2017

This study evaluated the effects of culture conditions, including carbon and nitrogen sources, L-monosodium glutamate (MSG), and initial pH, on gamma-aminobutyric acid (GABA) production by Lactobacillus brevis HYE1 isolated from kimchi, a Korean traditional fermented food. L. brevis HYE1 was screened by the production analysis of GABA and genetic analysis of the glutamate decarboxylase gene, resulting in 14.64 mM GABA after 48 h of cultivation in MRS medium containing 1% (w/v) MSG. In order to increase GABA production by L. brevis HYE1, the effects of carbon and nitrogen sources on GABA production were preliminarily investigated via one-factor-at-a-time optimization strategy. As the results, 2% maltose and 3% tryptone were determined to produce 17.93 mM GABA in modified MRS medium with 1% (w/v) MSG. In addition, the optimal MSG concentration and initial pH were determined to be 1% and 5.0, respectively, resulting in production of 18.97 mM GABA. Thereafter, response surface methodology (RSM) was applied to determine the optimal conditions of the above four factors. The results indicate that pH was the most significant factor for GABA production. The optimal culture conditions for maximum GABA production were also determined to be 2.14% (w/v) maltose, 4.01% (w/v) tryptone, 2.38% (w/v) MSG, and an initial pH of 4.74. In these conditions, GABA production by L. brevis HYE1 was predicted to be 21.44 mM using the RSM model. The experiment was performed under these optimized conditions, resulting in GABA production of 18.76 mM. These results show that the predicted and experimental values of GABA production are in good agreement.

• KSBB Journal
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• v.15 no.2
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• pp.195-200
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• 2000

Studies were made on the optimization of media to c비tivate Thraustochytrium aureum A TCC 34304 for the enhanc엉d p production of linoleic acid. The medium optimization was made with the artificial sea water medium. Yeast extract, sodium g glutamate, peptone and tryptone were considered as nitrogen source. The effect of $\infty$ncentration of nitrogen source as well a as initial glucose on the production of linoleic acid were investigated to optimize the media. The maximum yield of lipid was 0 0.302 mg/g cell mass when initial glucose $\infty$ncentration was 10 g/L and sodium glutamate was used as nitrogen source, a and the yield of linoleic acid to unit cell mass was also maximum to be 8 % in that case. The highest linoleic acid c concentration was obtained in the initial glucose concentration 30 g/L regardless of the kinds of nitrogen source and the | linoleic acid concentration was 0.208 g/L when peptone was supplemented to be 2 g/L.

• Journal of Mushroom
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• v.2 no.1
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• pp.21-27
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• 2004

Distribution and in vitro growth characteristics of entomopathogenic Paecilomyces species were studied based on the specimens and isolates deposited in Entomopathogenic Fungal Culture Collection (EFCC), Kangwon National University, Chuncheon, Korea. Paecilomyces species were frequently collected from different mountains and valleys and were almost distributed uniformly. Collection period of Paecilomyces species ranged from July to September, with most of the collections at the end of September. P. tenuipes was mostly collected one among different Paecilomyces species. The optimum medium for mycelial growth of P. tenuipes was PDA, whereas in other media such as SDAY and HMA also produced similar growth. The optimum temperature and pH levels were $25^{\circ}C$ and 6.0~7.0, respectively. Best carbon and nitrogen sources were dextrose and tryptone, respectively, while $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial growth was observed when the C/N ratio was 20:1.