• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.137-143
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• 2009

It has been reported that mechanical stimulation takes a role in improving eel/ growth in skeletal system. Various research groups have been showed their own bioreactors which stimulate cell-seed three-dimensional scaffold. In this study, we hypothesized that the various conditions of mechanical stimulation would affect cell growth and proliferation. To prove our hypothesis, we designed a custom-made bioreactor capable of applying controlled compression to cell-encapsulated scaffolds. This device consisted of a circulation system and a compression system. Each parts of the bioreactor was fabricated using the rapid prototyping technology By using the rapid prototyping technology, we can modify and improve the bioreactor very rapidly For dynamic cell-culture, cell-encapsulated agarose gel was fabricated in 2% concentration. We performed dynamic cell-culture using this agarose gel and developed bioreactor in 3 days.

• Microbiology and Biotechnology Letters
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• v.33 no.1
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• pp.29-34
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• 2005

Lipase-producing bacteria (S3) were isolated from intertidal flat at Saemanguem. A isolated strain was identified as Psychrobacter species by physiological and fermentational characterization as well as 16S rRNA analysis. The strain was then named as Psychrobacter sp. S3. P. sp. S3 grew most rapidly at $30^{\circ}C$, but grew well even at $10^{\circ}C$ and its lipase activity was most high when cultivated at $20^{\circ}C$. Lipase S3 had optimum temperature of $30^{\circ}C$ for the hydrolysis of p-nitrophenyl caproate and had more than $80^{\circ}C$ activity even at $10^{\circ}C$. The activation energy was calculated to be 1.5 kcal/mol, which showed that it was a typical cold-adapted enzyme. It was an alkaline enzyme with optimum pH of $9.0\~9.5$. It could hydrolyze various length of triglycerides. Among them, it hydrolyzed most rapidly $C_4,\;C_{14},\; C_{16}-length$ triglycerides. When added to tributyrin-agarose gel, lipase S3 hydrolyzed tributyrin most rapidly at 30 and $40^{\circ}C$, but it could hydrolyze well even at $4^{\circ}C$.