https://repository.kopri.re.kr/handle/201206/5526 2026-04-16T00:07:08Z 2026-04-16T00:07:08Z Bae, S.Y. Lee, Hong Kum Pyo, Suhkneung Yim, Joung Han https://repository.kopri.re.kr/handle/201206/6269 2022-03-24T07:13:55Z 2006-01-01T00:00:00Z

Title: Activation of murine peritoneal macrophages by sulfated exopolysaccharide from marine microalga Gyrodinium impudicum (strain KG03): involvement of the NF-κB and JNK pathway. Authors: Bae, S.Y.; Lee, Hong Kum; Pyo, Suhkneung; Yim, Joung Han Abstract: This study examined the ability of microalgal sulfated exopolysaccharide (MSE) from marine microalga Gyrodinium impudicum (strain KG03) to induce secretory and cellular responses in murine peritoneal macrophages. The cytotoxicity induced by preincubating tumor cells with MSE was demonstrated to be concentration-dependent. The MSE-induced tumoricidal activity was partially abrogated by a NO inhibitor, whereas the anti-TNF-？and anti-IFN-？/？antibodies as well as the scavengers of reactive oxygen intermediates had no effect. In addition, supernatants from murine peritoneal macrophages treated with MSE contained nitrite and their iNOS enzymatic activity was significantly increased. Therefore, the tumoricidal activity induced by MSE appeared to be mediated by the production of NO. Treating the macrophages with a JNK inhibitor (SP600125) partially blocked the tumoricidal activation and NO production induced by MSE, whereas inhibitors of the other kinases did not have an inhibitory effect. These results suggest that MSE induces NO production via the JNK dependent pathway. Furthermore, electrophoretic mobility shift assay analyses revealed that the MSE treatment induced the activation of the NF-κB transcription factor. Overall, these results indicate that the tumoricidal activity induced by MSE is mainly due to NO production, and the activation of macrophage by MSE is mediated probably via the NF-kB and JNK pathway.

2006-01-01T00:00:00Z An, Se Hoon Lee, Hong Kum Yim, Joung Han Park, Kyu Jin Lee, Yoo Kyung Kim, Sung Jin https://repository.kopri.re.kr/handle/201206/6615 2022-03-24T07:10:27Z 2005-01-01T00:00:00Z

Title: Production of novel exopolysccharide with emulsifying ability from marine microorganism, Alteromonas sp. strain 00SS11568 Authors: An, Se Hoon; Lee, Hong Kum; Yim, Joung Han; Park, Kyu Jin; Lee, Yoo Kyung; Kim, Sung Jin Abstract: . To find a novel exopolysaccharide, marine bacterial strains were isolated from coastal regions of Korea. Strain 00SS11568 was then selected as it produced a mucous exopolysaccharide during the stationary phase in a batch culture. The isolate was identi

2005-01-01T00:00:00Z Yim, Joung Han Lee, Hong Kum https://repository.kopri.re.kr/handle/201206/5938 2022-03-24T07:12:15Z 2004-01-01T00:00:00Z

Title: Axenic culture of Gyrodinium impudicum strain KG03, a marine red-tide microalga that produces exopolysaccharide Authors: Yim, Joung Han; Lee, Hong Kum Abstract: An exopolysaccharide-producing microalgal dinoflagellate was isolated from a red-tide bloom and designated strain KG03. A bacteria-free culture of strain KG03 was achieved using a modified wash with phototaxis and antibiotic treatment. Combined treatment with neomycin and cephalosporin was the most effective for eliminating the bacteria associated with the microalgae. Strain KG03 was identified as Gyrodinium impudicum by analyzing the ITS regions of the 5.8S rDNA, 18S rDNA, morphological phenotype and fatty acid composition. The exopolysaccharide production and cell growth in a 300-ml photobioreactor were increased 2.7- and 2.4-fold, respectively, compared with that in a flask culture at the first isolation step.

2004-01-01T00:00:00Z Yim, Joung Han Kim, Sung Jin An, Se Hoon Lee, Hong Kum https://repository.kopri.re.kr/handle/201206/6616 2022-03-24T07:13:57Z 2004-01-01T00:00:00Z

Title: Physicocehmical and rheological properties of a novel emulsifier, EPS-R, produced by the marine bacterium Hahella chejuensis Authors: Yim, Joung Han; Kim, Sung Jin; An, Se Hoon; Lee, Hong Kum Abstract: The rheological properties of an exopolysaccharide, EPS-R, produced by the marine bacterium Hahella chejuensis strain 96CJ10356 were investigated. The E24 of 0.5% EPS-R was 89.2%, which was higher than that observed in commercial polysaccharides such as xanthan gum (67.8%), gellan gum (2.01%) or sodium alginate (1.02%). Glucose and galactose are the main sugars in EPS-R, with a molar ratio of ~1:6.8, xylose and ribose are minor sugar components. The average molecular mass, as determined by gel filtration chromatography, was 2.2 x 103 KDa. The intrinsic viscosities of EPS-R were calculated to be 16.5 and 15.9 dl/g using the Huggins and Kraemer equations, respectively, with a 2.3 dl/g overlap. In terms of rigidity, the conformation of EPS-R was similar to that of caboxymethyl cellulose (5.0 x 10-2). The rheological behavior of EPS？R dispersion indicated that the formation of a structure intermediate between that of a random-coil polysaccharide and a weak gel. The aqueous dispersion of EPS-R at concentrations ranging from 0.25% to 1.0% (w/w) showed a marked shear-thinning property in accordance with Power-law behavior. In aqueous dispersions of 1.0% EPS-R, the consistency index (K) and flow behavior index (n) were 1,410 and 0.73, respectively. EPS-R was stable to pH and salts.

2004-01-01T00:00:00Z