• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.1-7
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• 1997

In order to utilize fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures Lactobacillus buigaricus KCTC 3188 and L. piantarum KCTC 1048 were used as a starter culture for the preparation of fermented fish silage with skipjark tuna viscera. The optimum temperature and pH on barterial growth and lactic acid production of L. bulgaricus and L. plantarum in MRS broth were $35^{\circ}C$ and around pH 6.0, respectively. And the optimum concentrations of the carbohydrate sources added to the broths were $7\%$ for dextrose and $10\%$ for molasses on the basis of total weights of skipjack tuna viscera. The pH of acid treated skipjack tuna viscera silage (ASS) slightly increased from 4.0 to 4.5, while that of fermented skipjack tuna viscera silages by the use of lactic acid bacterias (FSS) was significantly declined from 5.9 to about 40 after 42 days of storage at $35^{\circ}C$. Though the content of volatile basie nitrogen (VBN) in ASS was lower than those of FSS after 42 days of storage at $35^{\circ}C$, VBN content in silages slightly increased from an initial value of $62\~65{\cdot}mg/100g$ to final value of $113\~155\;mg/100g$ over 42 days. The fermented silage by L. piantarum reached a maximum concentration of amino nitrogen and showed $81\%$ of hydrolysis degree after 4 days of storage at $35^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.71-79
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• 1988

For the purpose of producing low salt fermented anchovy by accelerated method with a strong proteolytic bacteria, in this study, a strong proteolytic bacterium was isolated from low salt fermented anchovy and its bacteriological characteristics and properties of protease were experimented. The results obtained were as fellows : three proteolytic bacteria, Aeromonas anaerogenes Barillus subtilis and Staphylococcus saprophyticus were isolated from low salt fermented anchovy($4\%\;of\;salt,\;4\%\;of\;KCl,\;0.5\%\;of\;lactic\;acid,\;6\%$of sorbitol and $4\%$ of alcohol extract of red pepper) after 40 days fermentation. Among these strains, which grow best at $30^{\circ}C$, pH 7.0, B. subtilis was found the best proteolytic strain and benefit for industrial use as shown $0.95\;hr^{-1}$ of specific growth rate, $89{\mu}g-Tyr/hr.ml$ of maximum activity after 12 hrs culture in TPY broth. The protease produced by by B. subtilis showed maximum activity at $35^{\circ}C$, pH 7.0, and molecular weight was estimated to be 23,000 by Sephadex G-100 filtration, and it was supposed to be a kind of metal chelator sensitive neutral protease from the results of strong sensitivity against EDTA, o-phenanthroline and metal ions such as $Cu^{2+},\;Ni^{2+},\;Fe^{2+}.Km$ value of that by method of Lineweaver-Burk was determinded to be $0.73\%$ for casein as a substrate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.1
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• pp.57-62
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• 1987

The transformational conditions of plasmids $pPL-\lambda$ and pAS 1 are as follows in E. coli, Ts-mutant M 5248 strain at $30^{\circ}C$. When the culture time was 2.5 hours of mid logarithemic phase, the cell concentration was $4.5\times10^7\;cells/ml$, the optical density was equal to 0.45 at 590 nm wave length, the transformational frequencies of plasmid$pPL-\lambda$ and pAS 1 had the highest values as $2\times10^{-6}\;and\;1.5\times10^{-6}\;and\;1.5\times10^{-6}$ and respectively. For $9\times10^6$ competent cells in $200{\mu}l$, the transformational frequency was as high as $4.4\times10^{-6}$ at 510 ng plasmid concentration. The competent cells treated with the mixture of calcium chloride and thymidine twice rates of transformation than those treated with calcium chloride. The ampicillin resistance of transformants was expressed in LB broth after 2 hours at $30^{\circ}C$.

• The Journal of Natural Sciences
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• v.16 no.1
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• pp.15-29
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• 2005

To produce a thermostable cyclodextrin by using thermotolerant cyclomaltodextrin glucanotransferase(CGTase), a thermophilic and alkalophilic bacterium isolate, designated B-13 showing the highest CGTase activity was isalated from natural sources and identified as Bacillus cereus B-13 based on the morphological and physiological characteristics, and 16S rRNA sequence. The maximal CGTase activity (130 U/ml) was obtained when Bacillus cereus B-13 was cultured in SYC medium containing 2.0% soluble starch, 1.0% yeast extracts, 1% corn steep liquor and 1% $Na_2CO_3$ (pH 8.5) at $50^{\circ}C$ for 24 h and about 80% of maximal activity was also showed in he culture broth of $60^{\circ}C$ for 18 h. Optimum reaction temperature and pH of the partial purified CGTase for soluble starch were $65^{\circ}C$ and pH 8.5-9.0 respectively. The partial purified CGTase were also stable below $80^{\circ}C$ and pH 5.0-10.0. When 1% soluble starch was digested with the partial purified CGTase, the yield of cyclodextrin was 49%.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.145-152
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• 1994

In order to investigate the cultural characteristics of Lentinus lepideus, media, pH, carbon sources, nitrogen sources, vitamin and organic acids were tested in submerged culture. It grew well in GPB(broth), and the optimum temperature and pH was $25^{\circ}C$ and 4.2, respectively. The carbon sources such as galactose belong to monosaccharide and maltose belong to disaccharide were effective for mycelial growth. Peptone which is compound nitrogen source was good for mycelial yield but the other nitrogen sources were not effective. Among the various vitamins, pyridoxine is suitable for mycelial yield. Among the various organic acids, citric acid promoted the mycelial yield but acetic acid interrupted the mycelial growth of L. lepideus.

• Applied Biological Chemistry
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• v.27 no.3
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• pp.180-186
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• 1984

For the study of glucose oxidase(GOD) and catalase(CAT) coimmobilization system, the enzymes were obtained from Penicillium spp., PS-8, and the strain itself was used as an immobilizing matrix. To separate glucose oxidase and catalase after the ammonium sulfate fractionation of the culture broth, DEAF-cellulose column was used and its activity yield was 54 and 34%, respectively. Both enzymes were immobilized on the cell matrix, followed crosslinking with 2.5% glutaraldehyde for 12hr. In the determination of efficiencies of GOD and CAT of dual, mixed and soluble enzyme systems, the dual immobilized one w-as superior to those of the soluble or mixed ones. In the comparison of pH profiles, the dual and mixed types showed broader maximum pH ranges than the soluble type. Varying CAT/GOD ratio of the dual system, the higher the ratio showed the broader activity profile. In the comparison of apparent $K_m$ of GOD only and CAT/GOD=10, they were $7.1{\times}10^{-2}$ and $5.1{\times}10^{-2}M$. Their activation energies showed 3.98kcal/mole/deg for GOD only and 2.98kcal/mole/deg for CAT/GOD=10.

• KSBB Journal
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• v.14 no.6
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• pp.724-730
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• 1999

Characteristics and enzyme activity comparison was made between urokinase isolated from urine and pro-urokinase separated from CHO(Chinese Hamster Ovary) cell culture broth. Both of purified urokinase and pro-urokinase resulted 54Kd single band in electrophoresis. Urokinase which was proved as a single molecule by gel filtration showed two separated 33Kd and 21Kd bands by 2-mercaptoethanol reduction. Isoelectric forcusing resulted same pl value of 8.6 for both of them. N-terminal amino acid sequence of urokinase after 159th Ile was Ile-Gly-Gly-Glu-Phe-Thr-Thr-Ile-Glu which was different from another N-terminal sequence of Ser-Asn-Glu-Leu-His-Gln-Val-Pro-Ser-Asn. Thrombolytic activities of both of them were propotional to the enzyme concentration. Urokinase showed thrombolytic activities in an short period of reaction time. Pro-urokinase, however, showed high thrombolytic activity for 2 hours or longer period of reaction time.

• Journal of Environmental Health Sciences
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• v.31 no.5 s.86
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• pp.360-364
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• 2005

When rapeseed oil as the carbon source was used for tylosin production from Streptomyces fradiae TP-1239 was very sensitive to oleic acid. Cell growth was restrained by adding 0.8 g/l of oleic acid to the culture broth. Mutant strain TM-224-1 resistant to 1.2 g/l of oleic acid was obtained by screening in solid and liquid media containing oleic acid. The uptake rate of oleic acid by TM-224-1 was approximately 3.8 fold higher than the parent strain. For comparing the TM-224-1 and the parent strain, batch cultures were carried out in a jar fermentor. Cell growth of TM-224-1 strain was higher than the parent strain after two days of culturing. However, after four days of culturing, it was similar to that of the parent strain. The amount of rapeseed oil consumed by TM-224-1 and the parent strain were 60.5 and 78.2 g/l, respectively. The production and yield of tylosin was aproximately 2.0 and 3.2 fold higher than the parent strain, respectively. From these results, it was concluded that this mutant, which was resistant to oleic acid, has improved tylosin production.

• Journal of Life Science
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• v.14 no.5
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• pp.834-839
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• 2004

To improve and oil degrading activity, the lipase gene from Pseudomonase sp. was transformed into Klebsiella sp. KCL-l, an oil degrading bacterium. The selected trasformant was named as a KCL-1/pET-Lip. The surface tension of culture broth of KCL-1/pET-Lip was decreased to 33 dyne/cm from 55 dyne/cm using 4% (v/v) soybean oil as sole carbon source. The surface tension were 44 and 37.5 dyne/cm, to 2% (w/v) glucose and 4% (v/v) kerosene medium, respectively. The emulsification activity of the biosurfactant solution containing lipase of KCL-l/pET-Lip improved better than wild type KCL-l. The soybean oil was most efficient carbon source and substrate for surface activity and emulsification activity of KCL-1/pET-Lip. The expression of lipase was confirmed by SDS-PAGE.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.970-973
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• 1996

Effect of cell density on the xylitol production from xylose by Candida parapsilosis KFCC 10875 was investigated. The concentrated cells were obtained by centrifugation of culture broth. The xylitol production rate was maximum at the cell concentration of 20 g/l and the specific xylitol production rate decreased when the cell concentration was increased due to oxygen limitation. Effect of the initial concentration of xylose on the xylitol production was also examined using the concentrated cells of 20 g/l. The xylitol production rate, specific xylitol production rate, and xylitol yield from xylose were maximum at 170 g/l xylose. Above 170 g/l xylose, the xylitol production rate was remarkably decreased. The concentrated cells could also be obtained by adjusting the dissolved oxygen (DO) during fermentation. The rapid accumulation of cells up to 20 g/l was achieved by maintaining an increased level of DO during the exponential growth phase and then, for the efficient xylitol production, the DO was changed to a low level in the range of 0.7-1.5%. A fed-batch fermentation of xylose by adjusting the DO level was carried out in a fermentor and the final xylitol concentration of 140 g/l from xylose of 200 g/l could be obtained for 56 h fermentation.