Changes in total lipid contents of marine diatom Nitzschia frustulum at various temperatures under Si deficiency

Abstract

The photosynthetic marine diatom Nitzschia frustulum was grown autotrophically in a photobioreactor in two stages. In the first stage, cells were grown for 7 days to Si deficiency at the optimally adapted temperature of 22 °C. In the second stage, they were grown for 2 more days at a new temperature ranging from 12 °C to 37 °C; then the contents of total lipids in the harvested diatom samples were measured. The total lipid content of the final diatom cells grown at the altered temperatures between 17 and 32 °C changed little from 15.1% (wt) of the dried cells harvested before the temperature changes. However, it increased to 21% (wt) for cells grown at a low temperature of 12 °C and decreased drastically to 7% (wt) at a high temperature of 37 °C.