Increased lipid productivity of Acutodesmus dimorphus using optimized pulsed electric field

An alternative stress-inducing method, a low-energy pulsed electric field (LE-PEF), was used to improve the lipid productivity of microalgae cultures. A large shift in the Nile-Red-stained peaks toward a higher intensity in fluorescent-activated cell sorting, suggestive of an increased neutral lipid content, was observed when 10 kV LE-PEF pulses were applied to 800 mL batch cultures of Acutodesmus dimorphus. The optimal LE-PEF on-off cycle treatment for A. dimorphus was 2 s on–60 s off for 15 min with 6 cycles per day. Under these optimal LE-PEF treatment conditions, A. dimorphus showed an overall 28.8 % increase in lipid productivity. Therefore, based on these results, LE-PEF can be regarded as a promising tool to avoid the lipid content and growth rate trade-off and improve the lipid productivity of microalgae in various cultivation systems.