• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1183-1186
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• 2007

A shake-flask method was used to determine the n-octanol/water partition coefficients of sulfamethazine, sulfadimethoxine, sulfamethoxydiazine, sulfamonomethoxine, sulfamethoxazole, sulfaquinoxaline and sulfachloropyrazine from (298.15 to 333.15) K. The results showed that the n-octanol/water partition coefficient of each sulfonamide decreased with the increase of temperature. Based on the fluid phase equilibrium theory, the thermodynamic relationship of n-octanol/water partition coefficient depending on the temperature is proposed, and the changes of enthalpy, entropy, and the Gibbs free energy function for sulfonamides partitioning in n-octanol/ water are determined, respectively. Sulfonamides molecules partitioning in n-octanol/water is mainly an enthalpy driving process, during which the order degrees of system increased. The temperature effect coefficient of n-octanol/water partition coefficient is discussed. The results show that its magnitude is the same as that of values in the literature.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.106-110
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• 2003

The study was carried out immobilized Aspergillus niger used of milk-wastewater. The purpose of investigation is to optimize the ermentational conditions of milk-wastewater The optimal pH, temperature and dilution rate were 3.0, 30$^{\circ}C$ and 0.025 h$\^$-1/. The maximum amount and yield of citric acid produced by immobilizes Aspergillus niger ATCC 9142 were 4.5g/1 and 70.3%. Compared to shake-flask culture, yield was increased about 20%.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.317-320
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• 2000

The optimal temperature and pH for both mycelial growth and exe-biopolymer production by Cordyceps millitaris in shake flask culture were found to be $20^{\circ}C$ and 6.0, respectively. Sucrose (4%) and corn steep powder (1%) were the most suitable carbon and nitrogen source for mycelial growth and exo-biopolymer production. The maximum specific growth rate $(0.142h^{-1})$ was achieved when sucrose was used as the sole carbon source. Exo-biopolymer production was increased with the increase in C/N molar ratio concentration, probably due to the facilitated carbon uptake. Under the optimal culture conditions, the maximum mycelial growth exe-biopolymer concentration were reached to around 13.3 g dry cell weigh/l and 3.33 g/l, respectively.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.546-551
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• 2005

[ ${\beta}-1,3-Glucan$ ] (curdlan) is a water-insoluble polysaccharide composed exclusively of ${\beta}-1,3\;linked$ glucose residues. Extracellular curdlan was mostly synthesized by Agrobacterium species and Alcaligenes faecalis under nitrogen-limiting conditions. In this study, we screened the microorganisms capable of producing extracellular curdlan from soil samples. For the first time, we reported Gram-positive bacterium Bacillus sp. SNC 107 capable of producing extracellular curdlan in appreciable amounts. The effect of different carbon sources on curdlan production was studied and found that the yield of curdlan was more when glucose was used as carbon source. It was also found that maximum production was achieved when the initial concentration of ammonium and phosphate in the medium was 0.5 and 1.9 g/L respectively. In this study the curdlan production was increased from 3 to 7g/L in shake flask cultures.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.364-367
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• 2005

This study investigated the production of antioxidant from Actinomyces culture supernatant. For the research of the natural marine antioxidant, several bacteria were isolated from the coast of Je-ju in Korea. An actinomycetes strains, S-1 was identified to a genus level 16S ribosomal DNA sequence and fatty acid analysis. From these results and other characteristics described in the Bergey's Manual, this strain was identificated as a Nocardiopsis dassonvillei. Strain S-1 showed high activity of 1,1-diphenyl-2-prcrylhydrazyl radical scavenging. The hydroxyl radical scavenging ability of Nocardiopsis sp. S-1 supernatant was 53%. Nutritional and cultural conditions for the production of antioxidant by this organism under shake-flask conditions have optimized. Similary initial medium pH 7.6, incubation temperature of $25^{\cicr}C$, sodium chloride concentration 2.5 and incubation time of 8 day were found to be optimal.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.568-571
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• 1999

Aspergillus oryzae U1521, which was a genetically engineered strain, produced 1,000,600 U per g . glucose of extracellular alkaline protease within 72 h in a submerged fermentation. However, the alkaline protease was not detected during the first 24 h. Northern blot analysis indicated that the enzyme synthesis was repressed at the transcriptional level during the lag period. Both catabolite repression and pH of the growth medium significantly affected the enzyme production. Use of this enzyme as a silver recovery agent from used X-ray film was confirmed by experiments in the shake-flask scale.

• KSBB Journal
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• 제14권3호
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• pp.365-370
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• 1999

To optimize the culture conditions for Beauveria bassiana 726, the effects of culture medium, pH, and temperature on mycelium and spore production were investigated. The optimum temperature and pH for the cultivation of B. bassiana 726 were 28 $^{\circ}C$ and 5.0, respectively. The optimized medium was composed of 1.0~2.0% total sugar from molasses, 0.5% corn steep liquor and 0.05% KH$_2$PO$_4$. In the cultivation of B. bassiana 726 with the optimum medium, the specific growth rate and substrate utilization were well-fitted with the proposed kinetic model in the shake flask and stirred tank reactor. When the fed-batch cultivation using carbon suorce, nitrogen source, and mineral salt as a feeding medium was compared with batch cultivation in stirred tank reactor, mycelium (12.7 g/L) and spore production (5.4$\times$$10^8/mL$) were enhanced up to 110% and 85%, respectively.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.486-493
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• 1993

A gram(+) bacteria that produced microbial flocculant was isolated from soil and classified as a Bacillus species and named as Bacillus sp. A56. The culture conditions of the strain for fluocculant production were studied in a shake flask. Optimum temperature and initial pH for flcculant production were 30C and 6.5, respectively. The optimized medium has gollowing composition: glucose 20g/l, NH4NO3 0.5g/l, K2HPO4 1.0g/l, KH2PO4 0.8g/l, MgSO4.7H2O 0.2g/l, MnSO4.4-6H2O 0.3g/l, CaCO3 0.5g/l, yeast extract 0.3g/l, tryptone 0.3g/l in tap water.

• 한국염색가공학회지
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• 제11권4호
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• pp.8-15
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• 1999

Electroconductive fiber was obtained by acryl fiber treated with $CuSO_4$. The Properties and structure of fiber and fabric such as mechanical property, electrical conductivity, fine structure, electrification were investigated. The experimental results are as follows 1) The electrical conductivity of the conducting fiber was greatly increased but fine structure and physical properties were similar to acryl fiber 2) Fabric made by mix spinning with conducting fiber was shown great electrification effect. 3) In the mix spinning with conducting fiber, it was necessary to use different. finishing such as milled finish because stiffness of fabric made by mix spinning with conducting fiber was increased and elastic recovery was decreased. 4) The antimicrobial activity of electroconductive fiber blended wool was effective by Cu component for shake flask test.

• Journal of Microbiology and Biotechnology
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• 제2권2호
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• pp.102-107
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• 1992

For the purpose of producing L-ornithine by microbial fermentation, mutant strains were developed from glutamate-producing bacteria by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV irradiation. Brevibacterium ketoglutamicum BK1046, a L-citrulline auxotroph which is also resistant to arginine hydroxamate (Arghx), was isolated and selected as the best producer of L-ornithine. This strain was capable of producing L-ornithine at a concentration of 24 g/l after 69 hours of cultivation in the 21 jar fermentor. The optimum supplementary level of L-arginine, a substitute for L-citrulline, was found to be about 0.2 g/l in the shake-flask fermentation.