• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.111-115
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• 1991

The green alga, Dunaliella salina under fed-batch cultivation produced 51.12 mg of hydrocarbon per liter with maintaining 0.313 (g dry wt/l). About 20% of hydrocarbon production yield based on dry biomass was obtained from both batch and fed-batch processes. Optimum culture conditions of light intensity, pH and salt concentration were obtained as 0.0080 (kJ/$cm^2$/h), 8.0 and 1.4 (g of NaCl/l), respectively by response surface analysis. The production of hydrocarbons in D. salina was closely correlated to cell growth. Fed-batch cultivation produced more hydrocarbons and maintained better cell growth than a batch process.

• Journal of Life Science
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• v.9 no.1
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• pp.22-28
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• 1999

A bacterium producing exo-inulinase was isolated from soil and identified Pseudomonas sp. and named as Pseudomonas sp. NO5. The optimal culture conditions for the efficient production of exo-inulinase from Pseudomonas sp. NO5 were obtained by cultivating with the medium 1$\%$ sucrose, 0.5$\%$ yeast extract, 0.5$\%$ $(NH_4)_2$$HPO_4$, 0.05$\%$ $MgSO_4$ㆍ$7H_2$0, 0.001$\%$ and $FeSO_4$ㆍ$7H_2$0 at $37^{\circ}C$ in initial pH 7.0 for 20 hours. The enzyme was induced maximally in the presence of sucrose or inulin at early stationary phase about 20 hour after cultivation.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.442-448
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• 2009

In this study Bacillus subtilis PTCC 1023 was used for the production of protopectinase using soybean based media. The use of isolated soybean protein (ISP) and soybean flour resulted in similar protopectinase production and growth rates. The effect of medium composition on protopectinase production was studied using central composite design (CCD) methodology. The change in the concentration of ISP (1-7%), glucose (0-10%), and phosphate (0.1-0.3 M) was found to affect the protopectinase activity (response variable) after 24 hr of cultivation. In the range studied, ISP and glucose had a negative effect on the response variable, whereas phosphate had a positive effect. A statistically significant interaction was identified between phosphate and ISP, suggesting that correct optimization of medium formulation in this case can only be obtained using factorial design of experiments. Protopectinase activity exceeding 215 U/mL was obtained in a medium containing 4% ISP, 0.3M phosphate, and no added sugar.

• Mycobiology
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• v.38 no.2
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• pp.137-143
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• 2010

The production of conidia of entomopathogenic Beauveria bassiana by solid-state fermentation was studied for the development of a biocontrol agent against aphid Myzus persicae. The optimal conditions for conidia production on polished white rice were 40% moisture content, $25^{\circ}C$ culture temperature, 2-day-old seeding culture grown in 3% corn meal, 2% rice bran, 2% corn steep powder medium, initial conidia concentration of $10^7$ conidia/g in the wet rice, 10% inoculum size, and use of a polyethylene bag as a container. The polyethylene bag containing inoculated rice was hand-shaken every 12 hr during fermentation. Using optimal conditions, the maximum conidia production obtained was 4.05 g conidia/100 g dry rice after 14 days of cultivation, a rate 2.83 times higher than conidia yield of pre-optimization.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.392-397
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• 2022

Methane is one of the major greenhouse gases, recently, the biotechnological conversion from methane to high-value added chemicals have emerged as an effort to reduce methane gas emission. In this study, we optimized ectoine bio-milking conditions in which cells were repeatedly used to improve intracellular and extracellular ectoine yield from methane by using Methylomicrobium alcaliphilum 20ZDP2. First, the cultivation and intracellular ectoine accumulation conditions were optimized with respect to the growth phase and medium salinity to achieve the highest yield of synthesis. Second, ectoine excretion was optimized by determining the ectoine secretion time (15 min) in appropriate medium salinity under hypoosmotic conditions (1% NaCl). Finally, bio-milking of ectoine was successfully repeated more than 10 times using M. alcaliphilum 20ZDP2, and the ectoine yield was improved up to 129.29 mg/ DCW g.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.242-242
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• 1979

The general efforts of applied research and development can be divided into product development, process development, process design, process equipment design, and operation The fed batch culture as one effort of theprocess development in fermentation industry has been practiced since the early times of human history. One particular industrial application with long history is in the cultivation of the baker's yeast where the glucose effect at relatively high glucose concentration is the general rule.

• 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 Microbiology and Biotechnology
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• v.23 no.9
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• pp.1229-1243
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• 2013

In this paper, an air isolate (NITT6L) has been screened based on hemolytic activity, emulsification activity, drop collapsing test, and oil displacement test, as well as lipase activity. It was found that strain NITT6L was able to reduce the surface tension of the medium from 61.5 to 39.83 mN/m and could form stable emulsions with tested vegetable oils. Morphological, biochemical, 16S rRNA sequencing analyses, and fatty acid methyl ester analysis using gas chromatography confirmed that the air isolate under study was Pseudomonas aeruginosa. Characterization of the biosurfactant using agar double diffusion assay revealed that the biosurfactant was anionic in nature, and CTAB-methylene blue assay and Molisch test revealed its glycolipid nature. The FT-IR spectrum confirmed that the crude biosurfactant was a rhamnolipid. Using unoptimized medium containing sucrose as the carbon source, the isolate was found to produce 0.3 mg/ml of rhamnolipid in batch cultivation (shake flask) at $37^{\circ}C$ and pH 7. Optimization of the medium components was carried out using design of experiments and the yield of rhamnolipid has been enhanced to 4.6 mg/ml in 72 h of fermentation.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.995-1002
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• 2018

Hairy root culture of ginseng is industrially prospected because the cultivation period of ginseng is relatively long. In this study, the effect of medium concentration and sucrose concentration on hairy root culture of ginseng was evaluated. The optimization of ginseng hairy roots transformed by Agrobacterium rhizogene were performed liquid medium. The MS(Murashinge & Skoog basal medium) concentration was selected with 1/2 strength MS and the optimal sucrose concentration was determined at 2-3%(w/v). At the optimum culture condition, The yield (the ratio of weight of grown hairy root cultures to weight of fresh ginseng hairy roots) and production rate of ginseng root were 19.42 times and 5.73 g/l-day. The major ginsenosides were Rb group, Re and Rg1. The produced total ginsenoside content in the solid medium was 9.87 (mg/g) and increased 1.34 times in the liquid medium (13.23 mg/g). In solid culture, the contents of ginsenosides Rb, Re and Rg1 were 2.14, 3.65 and 1.87 mg/g, respectively. In liquid culture, the contents of ginsenosides Rb, Re and Rg1 were 3.54, 4.12 and 2.63 mg/g, respectively.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.29-34
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• 1981

To maximize the production of penicillin amidase from Estherichia coli (ATCC 9637), the media composition and several factors affecting the engyme production during fermentation were studied. The optimal media composition was found to be; 3.5% tryptone, 1.5% monosodium glutamate and 0.5% yeast extract. The addition of 0.15% phenylacetic acid as an enzyme inducer at the initial stage of cultivation increased the engyme productivity about 5 fold. It was found that the engyme activity reached maximum within 16hr of cultivation. The maximum production of the enzyme obtained was about 102.5 units/l broth under the optimized condition. The enzyme production was markedly increased by the optimization as compared with those previously reported.