Pressurized liquid extraction with ethanol as a green and efficient technology to lipid extraction of Isochrysis biomass

This work was the first time to establish a green pressurized liquid extraction (PLE) process to extract microalgal lipids from Isochrysis biomass. PLE with ethanol exhibited superior lipid extraction performance in comparison to Soxhlet and Folch methods and PLE with n-hexane. To reduce the cost in ethanol utilization, ethanol concentration was optimized and found that PLE with 90% ethanol concentration obtained the highest lipid extraction efficiency (41.5 wt%) and total fatty acids (TFAs) recovery value (92.17 wt%) using Isochrysis sp. biomass. Results about lipid class detected by TLC-FID technique showed that ethanol concentration distinctly affected the content of lipidic class during lipid extraction by PLE. Similarly, the process with 90% ethanol concentration achieved over 90 wt% of TFAs recovery values with three different Isochrysis species. Overall, PLE process mediated with ethanol was a promising approach to extract Isochrysis-derived lipids from sustainable microalgal biomass for food application.