• Journal of the Korean Ceramic Society
• /
• v.29 no.12
• /
• pp.997-1003
• /
• 1992

Ultra-fine hydroxyapatite powders were synthesized by the hydrothermal reaction of Ca(OH)2 suspension or Ca(NO3)2$.$4H2O solution with (NH4)2HPO4 solution, and the powders were characterized for each synthetic condition. Crystalline hydroxyapatite powders have average grain size of less than 50 nm. By increasing the reaction pressure, the crystallinity was improved, and the crystals were preferentially growing along c-axis. When Ca(NO3)2$.$4H2O of high solubility was used, hydroxyapatite of single phase was produced. However when Ca(OH)2 of low solubility was used more than 0.334 mol/ι, unreacted Ca(OH)2 remained. Diffraction spot patterns of transmission electron microscope show that powders synthesized by the hydrothermal reaction were composed of single crystals of hexagonal phase.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.3
• /
• pp.355-359
• /
• 2002

The Plackett-Burman experimental design was employed to evaluate the relative importance of medium constituents of each medium for enhanced griseofulvin production by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004. It was found that the medium constituents, sucrose, $K_2HPO_4,\;NaNO_3,\;and\;FeSO_4{\cdot}7H_2O$, significantly influenced the griseofulvin production by Penicillium griseofulvum MTCC 1898. In the case of Penicillium griseofulvum MTCC 2004, lactose, glucose, and $MnSO_4{\cdot}H_2O$ significantly influenced the griseofulvin production.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.3
• /
• pp.360-366
• /
• 2002

Central composite experimental design was employed to determine the optimal concentration of medium constituents for griseofulvin production by Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvum MTCC 2004. The optimal concentration of sucrose, $K_2HPO_4,\;NaNO_3,\;and\;FeSO_4{\cdot}7H_2O$ were found to be 48.08 g/1, 1.228 g/1 , 2.7 g/1, and 0.011 g/1, respectively, for Penicillium griseofulvum MTCC 1898, and for Penicillium griseofulvum MTCC 2004, 23.52 g/1, 43.67 g/1, and 0.0434 g/1 of glucose, lactose, and $MnSO_4{\cdot}H_2O$, respectively. The yield of griseofulvin under optimal composition of medium constituents increased by 1.26 and 1.38 times than prior to optimization, for Penicillium griseofulvum MTCC 1898 and Penicillium griseofulvutn MTCC 2004, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.8 no.3
• /
• pp.208-213
• /
• 1998

The effect of the addition of wheat bran to the growth medium on the production of cellulolytic enzymes of Trichoderma reesei Rut C30 was studied in batch culture using shake flasks. The activity of cellulase was enhanced by the addition of wheat bran to the cellulase production medium. $KH_2PO_4$-$K_2HPO_4$ buffer was used for pH control during cellulase production. As a result, high cellulase activities were obtained in shake flask culture; a CMC (carboxymethyl cellulose) activity of 125.78 U/ml was obtained from 2% Avicel- and 3% wheat bran-containing medium and an FP (filter paper) activity of 12.85U/ml was obtained from 1% Avicel- and 5% wheat bran-containing medium after 6 days of cultivation.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.12
• /
• pp.1932-1937
• /
• 2008

The R-amidase production by a newly isolated strain of Delftia tsuruhatensis ZJB-05174 was optimized in this paper. Effects of factors such as carbon sources, nitrogen sources, and inducers on amidase production were investigated. The medium composition was optimized using central composite designs and response surface analysis. The optimal medium components for enhanced amidase production were found to be as follows: glucose, 8.23 g/l; yeast extract, 11.59 g/l; 2,2-(R,S)-dimethylcyclopropane carboxamide, 1.76 g/l; NaCl, 1 g/l; ${KH_2}{PO_4}$ 1 g/l; and ${K_2}{HPO_4}$ 1 g/l. A maximum enzyme production of 528.21 U/l was obtained under the optimized conditions, which was 4.7 times higher than that obtained under initial conditions.

• Journal of environmental and Sanitary engineering
• /
• v.12 no.2
• /
• pp.59-64
• /
• 1997

For purification of a 70kDa toxic protein of mosquitocidal delta-endotoxin from B. thuringiensis strain H9B, immuno-affinity chromatography was performed. After separation of 70kDa toxic proteins from the delta-endotoxin of the strain H9B on SDS-PAGE, the 70kDa toxic protein was subcutaneously injected into rabbit for making a polyclonal antibody. A anti-70kDa toxic protein was purified by a column chromatography packed with protein A-sepharose 4B gels. The 70kDa toxic protein from delta-endotoxin of the strain H9B was also purified by an immuno-affinity chromatography packed with CNBr-activated sepharose 4B gels conjugated anti-70kDa toxic protein after elution with 1/10M citric acid-1/5M Na$_{2}$HPO$_{4}$ buffer(pH3.2) containing 0.5M NaCl. The 70kDa toxic protein was purified through only one step-separation system, was demonstrated by SDS-PAGE and immunoblot.

• YAKHAK HOEJI
• /
• v.12 no.3_4
• /
• pp.76-84
• /
• 1968

When 19-hydroxycholesterol acetate was added into CSD-10 in Nutrient Broth or in a mineral salts medium consisting of KH$_{2}$PO$_{4}$(0.1%), $K_{2}$HPO$_{4}$(0.1%), NH$_{4}$NO$_{3}$(0.1%), MgSO$_{4}$(0.02%), CaCl$_{2}$(0.002%), and FeCl$_{3}$(0.005%), a substantial amount of 19-hydroxyandrost-4-ene-3,17-dione was accumulated prior to accumulation of estrone. From this result and all of previous works, a tentative degradation pathway of 19-hydroxycholesterol acetate to estrone by CSD-10 was derived. 19-hydroxyandrost-4-ene-3,17-dione seems to be an attractive intermediate for the synthesis of 19-norsteroids.

• Journal of Industrial Technology
• /
• v.1
• /
• pp.61-66
• /
• 1981

In order to use as a starter after drying, optimum growth conditions of Str. thermophilus and L. bulgaricus were investigated. The results were as follows. The growth of Str. thermophilus was reached at stationary phase after 12 hours incubation and L. bulgaricus was after 6 hours. Str. thermophilus was grown well, in the medium containing 10% of skim milk, 2% of sucrose, 0.1% of KCl and 0.015% (v./v.) of soy-sauce. In the case of L. bulgaricus, 10% of skim milk, 2% of glucose, 0.5% of bacto-peptone, 0.1% of $K_2HPO_4$ and 0.02% of pyridoxine was suitable for the maximum growth.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.4
• /
• pp.582-586
• /
• 1995

The effects of cultural temperature and nutritional components on the production of ethanol using juice of Pyrus serotina as the substrate for Saccharomyces cerevisiae ATCC 4124 were studied. After anaerobic cultivation in 5L flask of a defined pear juice at 2$0^{\circ}C$, ethanol concentration of 11.5%(v/v) could be obtained. The addition of a small amount of K2S2O5 was essential for the successful production of ethanol. Ethanol concentration could be further enhanced by supplementing a small of various complex nitrogen sources. When 0.05% of yeast extract and 0.05% of (NH4)2HPO4 were added to a defined medium, ethanol concentration obtained after 7 day cultivation at 2$0^{\circ}C$ was 12.3%.

• Journal of the Korean Ceramic Society
• /
• v.40 no.12
• /
• pp.1154-1158
• /
• 2003

Hydrothermal deposition of hydroxyapatite coatings on $Al_2$O$_3$ substrates was studied using aqueous solutions of Ca(NO$_3$)$_2$ㆍ4$H_2O$ and (NH$_4$)$_2$HPO$_4$ containing EDTA disodium salt as a chelating agent for $Ca^{2+}$. For the precipitation of the coatings the EDTA-Ca$^{2+}$ chelates were dissociated thermally at 20$0^{\circ}C$ or decomposed by oxidation with $H_2O$$_2$ at 9$0^{\circ}C$. Scanning electron microscopy and X-ray diffraction were used to investigate the deposition behavior and the phase of the coatings. Hydroxyapatite coatings were not deposited with the thermal dissociation method, whereas uniform deposition of the coatings (about 0.7 $\mu\textrm{m}$ thickness) was obtained with the oxidative decomposition method. The coatings consisted of fine rod-like hydroxyapatite crystals (hexagonal structure) with 60-80 nm diameters, having some preferred orientation with their length (i.e., the c axis) perpendicular to the substrate.ate.