A precisely weighed ~0.2 g amount of ground freeze dried microalgae was extracted with 2 mL of different solvents methanol, diethyl ether and hexane for 30 min at room temperature (20 曟). The tube was centrifuged at 4 500 g for 10 min and the supernatant was recovered. The extraction was repeated with 2 mL of three different solvents and the two supernatants were combined. The residue was subsequently extracted twice, for 30 min at room temperature and the supernatants were combined. Then, the residues were further extracted twice with water (2 mL each time) for 30 min at 80 曟, which was considered appropriate according to the literature[29], and the supernatants were combined.