Dispersive Activity and Physical Properties of Exopolysaccharide (Cystan) produced by Cystobacter sp. MSL-9

The dispersing activity and physical properties of exopolysaccharide (Cystan) produced by Cystobacter sp. MSL-9 was studied. Dispersing activity of Cystan was measured by using bentonite, calcium carbonate, and kaolin. Rheological properties of Cystan were investigated by using a rheometer MCR300. It was found that dispersing activity of Cystan was maintained under various pH and temperature conditions. A particle size analyzer BI-9000AT was used for the particle size measurement of Cystan in aqueous solution. The high dispersing activity and stability under various pH and temperature conditions showed the feasibility of Cystan as a industrial biodispersant.

Cystan의 분산활성은 점토광물에 대한 침강속도가 완연히 느려짐을 확인하여 분산제로서의 성능이 우수함을 볼 수 있었으며, 넓은 범위의 중성 pH에서는 고르게 분산활성을 유지하는 것으로 밝혀졌다. 이는 rheological test에서도 알 수 있었는데, 여러 pH와 온도에서의 Cystan 용액의 점도측정결과 넓은 영역에서 pH 및 온도 변화에 따른 큰 차이가 없었다. Cystobacter sp. MSL-9에 의해 생산되는 Cystan은 분산활성과 안정성이 높으며 기존 화학분산제보다 환경친화적이어서 그 산업적 가치가 클 것으로 기대된다.