• Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.105-111
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• 1999

In order to produce functional chitin oligosaccharides, a chitinolytic bacterium was newly screened from the viscera of Korean bony fishes, and identified as Bacillus sp. LJ-25. For the production of chitinolytic enzymes, $1.0\%$ nutrient broth and $0.3\%$ colloidal chitin were used as nitrogen and carbon source, respectively. The optimal temperature, initial pH and concentration of NaCl for the enzyme production by Bacillus sp. LJ-25 were $30^{\circ}C$ 6.5-7.0 and $1.0\%$, respectively. The enzyme activity of Bacillus sp. LJ-25 increased until the incubation time of 168 hr, followed by a decrease in activity.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.307-311
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• 2000

Abstract Extracellular chitinase was purified from the culture liquid of the marine bacterium, Bacillus sp. LJ-25 , and its enzymatic properties were examined. The purified chitinase exhibited a single band on SDS-PAGE and the molecular weight was estimated to be approximately 50 kDa. The optimum pH and temperature for the enzymatic activity were 7.0 and $35^{\circ}C$, respectively. The activity of the chitinase was strongly inhibited by $Zn^{2+}$ and slightly inhibited by $Ba^{2+},{\;}Co^{2+},{\;}Mn^{2+},{\;}and{\;}Cu^{2+}$. The purified chitinase did not hydrolyze $p-nitrophenolN-acetyl-{\bata}-D-glucosaminide{\;}(GlcNAc)_2$ and Micrococcus lysodeikticus cells, which are known to be the substrates for exo-type chitinase. Among the hydrolyzates of colloidal chitin, $(GlcNAc)_2$ was in the highest concentration with small amounts of GlcNAc and $(GlcNAc)_3$..

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.369.1-370
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• 1998