“Solvent-free” ultrasound-assisted extraction of lipids from fresh microalgae cells: A green, clean and scalable process

► A solvent-free ultrasound assisted extraction of lipids from fresh microalgae. ► Nannochloropsis oculata was chosen as a microalgae model. ► Influence of operating parameters on the extraction yields will be studied. ► Response surface methodology was used to study the performance of the extraction.