• 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.

• Applied Biological Chemistry
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• v.36 no.5
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• pp.332-338
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• 1993

For the production of riboflavin, strain development of Ashbya gossypii NRRL Y-1056 was attempted by NTG(N-methyl-N'-nitro-N-nitrosoguanidne) treatment. The optimum composition of culture medium and other culture conditions for the production of riboflavin by selected mutant Ashbya gossypii JAG-13 were determined. The optimum composition of medium was 9% of corn oil, 3% of gellatone, 4% of CSL, 0.3% of glycine, 0.2% of S770. The optimum culture temperature and initial pH of medium was $28^{\circ}C$ and 6.5, respectively. oxygen was essential for the production of riboflavin, but excess oxygen inhibit the production of riboflavin. When Ashbya gossypii JAG-13 was cultured under above conditions for 12 days with a bioreactor, 6.9 mg/ml of riboflavin was produced.

• Microbiology and Biotechnology Letters
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• v.47 no.2
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• pp.220-233
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• 2019

Bacterial lysates have become a common ingredient for natural health care. Lactic acid bacteria (LAB) could serve as potential candidates for lysate production: the lactic acids produced by LAB have been utilized for their moisturizing, antimicrobial, and rejuvenating effects, while other substances provide topical benefits and health effects for the skin. Our study aimed to obtain lysate from a LAB S. macedonicus MBF 10-2 through an optimized fermentation using the Response Surface Methodology. Strain MBF10-2 was cultivated in a 2L fermenter tank in de Man Rogosa and Sharpe (MRS) medium and in plant-based peptone modified MRS, i.e. Soy-peptone and Vegitone. The duration and the medium composition (dextrose and soy peptone or proteose peptone) were adjusted to obtain an optimum production of cell lysate. Central Composite Design was employed for Design Expert 7.0.0 by adjusting 3 factors: dextrose (1%, 1.5%, 2%, 2.5%, 3%), soy or proteose peptone (0.5%, 0.75%, 1%, 1.25% and 1.5%), and duration of fermentation (8, 10, 12 14, and 16 h for MRS-Soy peptone and 15, 17, 19, 21, and 23 h for MRS Vegitone). Bacteriocin-Like Inhibitor Substance activity of lysate and pH were used as indicators. The optimum condition for lysate production using MRS Soy Peptone and Vegitone are as follows: dextrose concentration 2.5%, plant-based peptone 1.25%, while optimum fermentation duration were 11.18 h (MRS Soy Peptone) and 17 h (MRS Vegitone) with a starter concentration of 10% at $OD_{600nm}$ $0.2{\pm}0.05$. However, the standard MRS medium produced better quality lysate compared to MRS plant-based peptones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.845-848
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• 1994

The fermenting conditions for acetic acid production with Acetobacter sp. FM-10 which could grow in the medium containing 10% ehtanol were investigated. Initial concentration of acetic acid in broth medium affected greatly to the fermentation speed. For example , the acetic acid production increased proportionally by the increasing of initial concentration was higher that 1.0%. When the cultivation was started with broth medium containing 5% ethanol, the additional adding ethanol during the fermentation was not significantly increased the acidity of the medium. The acidity of the medium containing 10% ethanol was reached to 8.3% after shaking than static cultivation by about 10 days with 150 rpm shaking speed. Acetic acid production with shaking cultivation was faster the static cultivation by abot 10 days under the same condition except shaking. In acetic acid fermentation with the batch style fermentor , the optimum fermentation condition was 700 rpm of agitation speed and 5L/min air flow rate in 3L culture medium .

• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.123-128
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• 2000

To enhance in vitro plantlet regeneration efficiency of soybean through embryogenesis, the culture conditions such as material part and size of immature seed, 2,4-D, pH and solidifying agents for somatic embryogenesis were investigated. Somatic embryogenesis was induced from the immature embryo, immature cotyledon and embryonic axis explants of the immature seed on MS medium supplemented with 2.0 mg/L 2,4-D. The highest rate (up to 22.9%) of somatic embryogenesis was obtained from the immature cotyledon, following embryonic axis and the immature embryo. The rate varied with the developmental stages of seed. The maximum rate (25.4%) of embryogenesis was obtained from 3-4 mm length of the seed (after 25 days of flowering). The optimum concentration of 2,4-D for embryogenesis was 10 mg/L. The optimum pH was at 5.8 and solidifying agent for medium was better with 0.4% gelrite than with agar. For rapid multiplication of shoot tips from the germinating somatic embryos, they were cultured on MS medium containing 2 mg/L indole-3-butyyic acid (IBA) and 1 mg/L 6-benzyladenine (BA). After then somatic embryos with one and three cotyledons were transferred to the growth regulator free medium. The medium exhibited the higher rate (ca. 50%) of development than the multiplication medium.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.265-272
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• 2006

This study was conducted to investigate the efficient propagation method of Cyrtomium caryoptideum var. coreanum by sporophyte culture. The influence of origin of explant sources (rhizome, blade, or stipe) and homogenization of culture materials on shoot regeneration were investigated. As a result, only rhizome explant exhibited the organogenic capacity and the shoot regeneration was promoted by homogenization of culture material. Vigorous and excellent growth of multiple shoots was induced on the half-strength of inorganic salts containing MS medium. It was appeared that optimum nitrogen content of shoot regeneration was half-strength of nitrogen containing MS medium (30mM) and optimum sucrose concentration was 1%. Addition of $NaH_2PO_4$ to culture medium generally enhanced shoot multiplication and promoted growth of the regenerants. The organogenic capacity of homogenized rhizomes was especially promoted on medium supplemented with $5{\mu}M$ kinetin plus $5{\mu}M$ IBA. The incorporation of $0.1\sim0.2%$ activated charcoal on medium supplemented with growth regulators prevented the formation of multiple bud primordia - nodule-like bud clusters and improved the normal morphogenesis of sporophytes.

• KSBB Journal
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• v.25 no.6
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• pp.539-546
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• 2010

In this work, mass production of Bacillus licheniformis SCD121067 through medium optimization by statistical experimental method was studied. First, galactose, yeast extract and potassium phosphate dibasic were selected as carbon, nitrogen and phosphate sources for mass production of B. licheniformis SCD121067 by using one factor at a time method. Second, according to the result of Plackett-Burman experimental design, key factors was yeast extract and $K_2HPO$. Finally, the response surface methodology was performed to obtain the optimum concentrations of two selected variables. The optimized medium composition consisted of 20 g/L galactose, 36 g/L yeast extract, 0.41 g/L $K_2HPO4$, 0.25 g/L $Na_2CO_3$, 0.4g/L $MgSO_4$ and 0.01g/L $CaCl_2$. Dry cell weight (15.4 g/L) by optimum production medium were increased 10 times, as compared to that determined with basic production medium (1.5 g/L). Fermentation conditions were examined for the mass production of B. licheniformis. The effect of temperature, agitation speed, pH and aeration rate on the mass production of B. licheniformis were also studied in a batch fermenter which was carried out in a 2.5 L bioreactor with a working volume of 1.5 L containing optimized production medium. As a result, dry cell weight of batch culture was 30.7 g/L at $42^{\circ}C$, 300 rpm, pH 8.0 and 2 vvm.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.93-98
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• 1984

The effects of cultural conditions on the mycelial growth and fruit-body formation and the yield of Pleurotus sajor-caju grown in rice straw medium were examined. The change of content of chemical components of mushroom and the medium during the cultivation period was also examined. The growth of mycelium was best in the medium sterilized for 60 min at $1.2kg/cm^2$ with a moisture content of 60%. The optimum pH and temperature for mycelial growth were 6.0 and $25^{\circ}C$, respectively, whereas the optimum pH and temperature for fruit-body formation ranged from 5.0 to 6.0 and from 20 to $30^{\circ}C$, respectively. Rice bran and starch cake were better than the other additives used for both mycelial growth and fruit-body formation. The optimum concentration of rice bran in the medium was 10%. The total yield of mushroom was $20.2kg/m^2$, 66% of which was prouduced from the first and second cropping period. As the harvest proceeded, the crude fiber cotent increased in the mushroom, whereas it decreased in the medium. The content of free sugar and crude ash, on the other hand, decreased in the mushroom, whereas it increased in the medium. The content of the other chemical components examined decreased in both the mush­room and the medium.

• The Korean Journal of Mycology
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• v.15 no.4
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• pp.238-246
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• 1987

Aspergillus niger van Tieghem was cultured by the method of synchronous and submerged culture. The sporulation occurred through the culture and its life cycle and differentiation were completed in the experiments. The effects of cAMP, theophylline and caffeine on the sporulation of A. niger were investigated. In the sporulation medium, the sporulation was stimulated by addition of cAMP and its optimum concentration was $10^{-4}M$. In the sporulation medium, the sporulation was stimulated by addition of theophylline and its optimum concentration was 10 mg/ml. In the sporulation medium, the sporulation was stimulated by addition of caffeine and its optimum concentration was 300 mg/ml. Theophylline added to the sporulation medium together with cAMP enhanced the promotion effect of cAMP on sporulation. Caffeine added to the sporulation medium together with cAMP enhanced the promotion effect of cAMP on sporulation. In the sporulation medium, the sporulation was stimulated by addition of neither AMP nor ATP. In the potassium acetate medium, cAMP, theophylline and caffeine stimulated the sporulation, respectively.

• Journal of Microbiology and Biotechnology
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• v.24 no.12
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• pp.1622-1628
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• 2014

DagA, a ${\beta}$-agarase, was produced by cultivating a recombinant Streptomyces lividans in a glucose medium or a mixed-sugar medium simulating microalgae hydrolysate. The optimum composition of the glucose medium was identified as 25 g/l glucose, 10 g/l yeast extract, and $5g/l\;MgCl_2{\cdot}6H_2O$. With this, a DagA activity of 7.26 U/ml could be obtained. When a mixed-sugar medium containing 25 g/l of sugars was used, a DagA activity of 4.81 U/ml was obtained with very low substrate utilization efficiency owing to the catabolic repression of glucose against the other sugars. When glucose and galactose were removed from the medium, an unexpectedly high DagA activity of about 8.7 U/ml was obtained, even though a smaller amount of sugars was used. It is recommended for better substrate utilization and process economics that glucose and galactose be eliminated from the medium, by being consumed by some other useful applications, before the production of DagA.