Title:
High-performance mega-saccharides derived from Aphanothece sacrum

Speaker:
T. KANEKO1*, K. OKEYOSHI, S. TATEYAMA, M. K. OKAJIMA

Department of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan. e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract:
We have studied mega-polysaccharide, sacran, produced by cyanobacteria, Aphanothece sacrum, which is a freshwater unicellular cyanobacterium, to demonstrate that sacran contains carboxyls and sulfate groups1. Furthermore the constituent sugars of the sacran were mainly determined as Fuc, Rha, Xyl, Man, Glc, Gal. In addition, we confirmed that the sacran was supergiant with a high absolute Mw of 2.35 x 107 g/mol.2  The sacran showed very high zero shear viscosity (80 000 cps) and unique behavior in the presence of salts such as shear thickening. Furthermore, sacran absorbed very large quantities of water and saline (0.9 % NaCl aq), 6300-6400 and 2700-2800 times to the dry weight of the sacran.


Figures


Fig.1 a) Figure of Aphanothece sacrum biomaterials. b) picture of extracted polysaccharides, sacran


References
[1] M. Okajima, M. Ono, K. Kabata, T. Kaneko, Pure Appl. Chem. 2007, 79(11), 2039.
[2] M. Okajima, T. Bamba, Y. Kaneso, K. Hirata, S. Kajiyama, E. Fukusaki, T. Kaneko, Macromolecules, 2009, 41(12), 4