was dried on aluminum weigh pans in a forced-air oven at
55°C for 48 h until no further weight loss was measured.
Since the study goal is to estimate feed supplement value
of algae byproduct, the de-oiling process was applied to
dried algae simulating the algal residue utilization after
biodiesel extraction. Oil was extracted from the dried algal
biomass using a SoxTec 2050 (FOSS, Eden Prairie, MN,
USA) with hexane (99.9% HPLC grade) as the solvent for
a 12 h reflux time. Residual solvent in biomass was evaporated
under a laminar flow hood for 48 h to leave de-oiled
algal residue.