https://repository.kopri.re.kr/handle/201206/5346 2026-04-07T05:40:34Z https://repository.kopri.re.kr/handle/201206/6612 Title: Enhanced Production ofEndochitinase from An Antarctic Bacterium,Sanguibacter antarcticus PAMC21702, in Pichia pastoris Authors: Han, Se Jong; Yim, Joung Han; Koh, Hye Yeon; Park, Heeyong; Lee, Sung Gu Abstract: The recombinant endochitinase (rChi21702) from a psychrophilic Antarctic bacterium, Sanguibacter antarcticus (KCTC 13143, PAMC 21702), has been produced using Pichia pastoris expression system. In this study, the optimum fermentation temperature (20°C) and growth media pH (6) for Chi21702 production was determined using a 2-stage fed-batch culture system. The maximal enzyme activity (178 U/l) of rChi21702 obtained using a glycerol-methanol fed-batch culture system was approximately 6-fold higher than that of unoptimized conditions. In addition, the rChi21702 exhibited cold-active endochitinase activity and higher thermal stability than that of the wild-type Chi21702. This work allows for large-scale production of rChi21702, which could be extended to further application studies using recombinant chtinases. 2014-01-01T00:00:00Z https://repository.kopri.re.kr/handle/201206/8009 Title: Effect of carbon sources on the fed-batch production of prodigiosin by Hahella chejuensis M3349 Authors: Yim, Joung Han; Lee, Hong Kum; Park, Heeyong; Lee, Sung Gu; Han, Se Jong Abstract: In order to increase prodigiosin production from Hahella chejuensis M3349, fed-batch cultures using various carbon sources were performed in 5L jar fermentor for 6 days. Cells were subjected to prodigiosin extraction using 1.2 vol. ethanol of culture broth. Concentration of prodigiosin extract was diluted to 10ppm and then algaecidal activity of diluted prodigiosin was measured against Cochlodinium polykrikodes which leads to red tides. Ultimately, prodigiosin production of 1.34, 0.77 and 2.35g/L was obtained and algaecidal activity of 93.05±2.3, 95.22±2.3 and 98.14±1.53% was confirmed when fed-batch culture was performed with sucrose, glycerol and glucose, respectively. This work shows that glucose was the best candidate for enhanced algaecidal activity and productivity of prodigiosin from Hahella chejuensis M3349 by fed-batch. [This work was supported by a grant from the Korea Polar Research Institute (PE10050 and PK09040).] 2010-01-01T00:00:00Z https://repository.kopri.re.kr/handle/201206/7962 Title: The effect of temperature and pH on psychrophilic chitinase expression in Pichia pastoris X-33 Authors: Han, Se Jong; Park, Heeyong; Yim, Joung Han; Koh, Hye Yeon; Lee, Sung Gu Abstract: To confirm the optimal cultivation conditions of Pichia pastoris X-33 containing the psychrophilic chitinase gene cloned from Antarctic microorganism, Sanguibacter antarcticus KOPRI 21702, the effect of temperature and pH on chitinase expression was investigated in a jar fermentor. Expression of target protein was performed by methanol addition and confirmed by an activity assay with p-nitrophenyl-N-acetyl- -D-glucosaminide as a substrate. Cells were grown at various temperatures ranging from 20 to 30  C and pHs from 5.5 to 6.5. The chitinase production was divided into two phases: batch and induction fed-batch. Ultimately, the optimal temperature and pH for the production of chitinase were found to be 20  C, pH 6.0, respectively. 2009-01-01T00:00:00Z