| 초록 |
The cell wall of diatoms, unicellular photosynthetic eukaryotes, is silica structure with two dimensional pore arrays. Recently, it was suggested that nano-structured titanium dioxide can be metabolically incorporated into the surface of living diatoms (Biogenic TiO2 particle). We obtained several species, Navicula sp. (#1271), Nitzschia incospicua (KMMCC-515), Berkeleya fragilis (KMMCC-1300) and Calonies schroederi (KMMCC-900) form Korean culture bank and testified which one is adequate for biogenic deposition of TiO2. We cultured each species in natural sea water supplemented with f/2 nutrients in the photo-bioreactor. A two-stage culture strategy was employed to incorporate titanium into each diatom silica frustule; In stage I, diatom cells grown up in dissolved silicon until silicon starvation. In stage II, soluble titanium and silicon were continuously fed to the silicon-starved cell. In the view of growth rate, Navicula sp. and Calonies schroederi seemed adequate. Analysis and comparison of SEM images of both species after SDS treatment showed that frustule of Calonies schroederi is stronger than that of Navicula sp. |
