3.3. Oil yield and biodiesel characteristics
Based on knowledge, lipid accumulation in oil bodies of algae
occurs during growth rate decrease, thus harvesting of Thalassiosira
sp. biomass for biofuel was carried out at the beginning of the stationary
phase (on the 6th day). Oils obtained from microalgae cultured
in both Walne and enriched seawater media were yellow
(Table 1). Shades of green oil were also observed when the oil contained
chlorophyll pigments. The amount of oil extracted from
10.1 g wet Thalassiosira sp. biomass (cultured in Walne medium)
was 2.1 mL, whereas from 7.0 g wet biomass (cultured in enriched
seawater medium) was 4.9 mL. Therefore, the oil productivity of
Thalassiosira sp. cell cultured in Walne medium and enriched seawater
medium was 150 and 290 lL d-1 L-1 culture, respectively.