• Applied Chemistry for Engineering
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• 제8권4호
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• pp.624-630
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• 1997

Zeolite A helps an increase of detergency performance according to showing the ion exchange effect for polyvalant ions and it's detergency performance could be calculated quantitatively by using the disperse stabilization theory because it is water-insoluble material and is as colloid particles in aqueous solution. In this study, zeta potential of carbon black, cellulose, and Zeolite A were measured in each inorganic salt solutions and applied to the theory of Heterocoagulation in order to evaluate the detergency performance of Zeolite A about the particulate soil at the view point of interaction potential energy. Zeolite A was shown help an increase of detergency performance according to the increasing of the steric repulsion between Zeolite A and cellulose in $Na2CO_3$ solution and the decrease of re-deposition of carbon black on the fabric by rapid coagulation with carbon black in $Na_2SO_4$ solution.

• Journal of Life Science
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• 제14권5호
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• pp.815-820
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• 2004

A bacterum containing antitumor activity was isolated from traditional korean food, Jeotgal. Through the 16s rRNA sequence analysis, the bacterium was identitied as a strain of Bacillus subtilis SW-l. The best culture condition for antitumor activity of the bacterium is 3% of soluble starch and 1 % of yeast extract as corbon and nitrogen sources, respectively. Cytotoxicitic concentrations of the culture supernatant of B. subtilis SW-1 against cancer cell lines, A549 and SK-OV3 were 30 ul/ml and 40 ul/ml, respectively, as $IC_{50}$/ values. In DNA fragmentation assay, the culture supernatant showed the programmed cell death (apoptosis) to cause degrading the chromosomal DNA like ladder. Taken together, the culture supernatant of the B. subtilis SW-1 has some possibility to be used as an antitumor agent.

• Journal of Mushroom
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• 제2권1호
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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.

• Journal of Korean Society of Forest Science
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• 제97권3호
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• pp.285-290
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• 2008

This study was carried out to obtain an optimal liquid culture condition for Sarcodon aspratus mycelia. Among various basal culture media the GYS (glucoe-yeast extract-soytone) medium was the best for mycelial growth. The appropriate temperature was $25^{\circ}C$. Starch, maltose or glucose was excellent carbon sources for the mycelial culture, compared to others tested. As nitrogen nutrients, soytone and $NH_4-N$ were the best organic and inorganic nitrogen sources, respectively. Moreover, the optimal concentration of soytone was 3 g per one-liter medium. In addition, we also found that alanine, $(NH_4)H_2PO_4$, and nicotinic acid were the best aminoacid, phosphorus salt, and vitamin, respectively. When all optimal conditions described above were applied to culture medium, we were able to produce 5.7 g dry weight of S. aspratus mycelia per one-liter liquid medium within 20 days.

• Microbiology and Biotechnology Letters
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• 제15권6호
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• pp.381-387
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• 1987

Distribution of superoxide dismutase (SOD) which catalyzes the dismutation of superoxide radicals to hydrogen peroxide and oxygen has been examined in various genera of bacteria. SOD was produced by various bacteria independent of genus and species with variation in superoxide dismutase activity of each bacteria. Bacillus circulans which produced relatively large amount of SOD was selected and used to investigate the optimum culture conditions and further studies. The compositions of optimum culture medium for the enzyme production were 1% glucose, 2% polypeptone, 0.l% NaCl, and 0.2mM of methyl viologen and initial pH was 6.0. The highest enzyme production was observed after 20 hours of cultivation at 3$0^{\circ}C$ on a reciprocal shaker. The enzyme activity was maintained stably for a relatively long period by the addition of 5% ethanol in pH 5.0, 0.01M acetate buffer.

• Microbiology and Biotechnology Letters
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• 제17권3호
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• pp.224-230
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• 1989

For the production of catechol from benzene, bacteria capable of assimilating benzene as a sole carbon and energy source were isolated from soils. Among them, newly isolated strain, KY-114 hay-ing the best ability of producing catechol from benzene was selected and a mutant Pseudomonas sp. HW-103 was developed from Pseudomonas sp. KY-114 by using mutagenesis induced by N-methyl - N'- nitro - N -nitrobo guanidine. The catechol reduction from benzone by Pseudomonas sp. HW-103 was investigated under various conditions. The highest catechol concentration (0.61 g/$\ell$) was obtained in the growth medium (pH 6.5) containing 1% sodium citrate, 0.75% (NH$_4$)$_2$SO$_4$, 0.15% benzene and other minerals at 3$0^{\circ}C$ after incubating of 15hrs. In the catechol production through the reaction with resting rolls, 2.5 g/1 of catechol was produced from 4 g/$\ell$ of benzene after incubation of 10 hrs under the optium conditions, which correponds to 45% of theoretical catechol yield.

• Applied Biological Chemistry
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• 제33권2호
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• pp.154-160
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• 1990

A bacterial strain which was capable of producing extracellular soymilk-clotting enzyme was isolated from soil samples during the course of screening test. The characteristics of the isolated strain K-324-7, indicated that the strain belonged to species of Bacillus cereus. The crude purification of this enzyme was precipitated by salting out with ammonium sulfate of 0.8 saturation. The optimal pH for the enzyme activity was at $6.1{\sim}7.0$ and below $50^{\circ}C$. The optimal culture medium for the production of soymilk-clotting enzyme were consisted of 0.2% glucose, 0.2% peptone, and 0.5% $KH_2PO_4$ with initial pH value of 6.5. The activity of enzyme was maximum when the microbe was cultured for 3 days at $35^{\circ}C$.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.93-105
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• 2012

Activity coefficients and solubilities of L-Valine and L-Proline in aqueous solutions containing each of four electrolytes such as NaCl, KCl, $NaNO_3$ and $KNO_3$ were measured at 298.15 K. The measurements of activity coefficients were carried out in the electrochemical cell coupled with two ion-selective electrodes (cation and anion), and the solubilities were measured by the gravimetric analysis of saturated solutions in equilibrium with the solid phase of amino acid. The measured activity coefficients of electrolytes and amino acids were correlated with the theoretical thermodynamic model presented in the previous work [Korean Chem. Eng. Res. 48(4), 519(2010)]. It was found that the activity coefficients of amino acids and electrolytes described based on the our previous model were well agreeable with experimental data. Also the experimental solubility data of L-Valine and L-Proline were successfully correlated with the thermodynamic relation mentioned in the previous work.

• Solar Energy
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• 제18권3호
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• pp.89-94
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• 1998

The heat transfer characteristics of a fluidized bed latent heat storage system using encapsulated PCM was investigated. The cylindrical test section has the dimension of 50 mm I.D. and 40 cm in height. The phase change material(PCM) was the sodium acetate and was encapsulated by the multiple layers of PMMA and paraffin wax. The size of encapsulated PCM was $2{\sim}3mm$ and melting point was $58^{\circ}C$. The instantaneous heat storage and heat release rates were determined and the instantaneous heat transfer coefficient based on the fluidized bed volume was also determined. The effect of inlet temperature and velocity of heat transfer fluid on the heat transfer coefficient was also investigated.

• Microbiology and Biotechnology Letters
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• 제20권3호
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• pp.263-270
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• 1992

For the selection of powerful antagonistic bacterium for biological control of soil borne Eminia carotovora subsp. carotovora causing rot of vegetable, excellent strains (S4, S14, 565) were selected from 1,196 strains of bacteria which were isolated from rhizosphere in vegetable root rot-suppresive soil. Strains were identified to be Pseudomonas species with Api 20NE kit. Antagonistic substance was produced in 523 synthetic broth medium at pH 7~8 and $30^{\circ}C$ during 3 days culture. The substance was stable in the pH range of 6 to 9. When the basal medium was supplemented with mannitol and sorbitol as carbon source and calcium chloride as metal salt, the production of the inhibitory substance was increased. The inhibitory acitivity was increased by the addition of fertilizer in soil. The isolated strains were resistant to the agricultural chemical such as benomyl and fosethyl-Al-folpet, and the antibiotics such as penicillin and lincomycin. We had found that Pseudomonas sp. S14 strain had a single plasmid. After treated with acridin orange for curing, we confirmed the existence of antagonistic gene in the chromosomal DNA.