Different Cell Disruption and Lipid Extraction Methods from Microalgae for Biodiesel Production

Microwave-Assisted Brine Extraction for Enhancement of the Quantity and Quality of Lipid Production from Microalgae Nannochloropsis sp.

“…The conventional techniques commonly involve chemical extraction methods that depend on diffusion of organic solvents through microalgae cells, such as hexane or hexane/isopropanol mixture via Soxhlet extraction [11], chloroform/methanol in Folch [12] and Bligh and Dyer methods (B&D) [13]. On the other hand, the non-conventional techniques depend on disruption of microalgae cell wall using mechanical equipment such as bead mills [14] and expeller press [15]. Other non-conventional methods are usually coupled with solvent extraction, for instance, microwave-assisted extraction (MAE) with chloroform/methanol [16] or with a mixture of isopropanol/hexane [17] and ultrasound-assisted extraction with hexane or methanol [18].…”

Lipids from Microalgae for Cosmetic Applications

“…The following step is the extraction of lipid products. In the literature, several techniques were reported for microalgal lipids extraction, mostly used for lipids recovery for biodiesel production [70]. No method can be considered effective as each microalga species has very specific characteristics.…”

“…An example of biomass pre-treatment method is grinding that involves mixing the freeze-dried biomass with liquid nitrogen through a ceramic mortar and pestle. Bead vortexing leads to microalgae cell walls breaking by grinding and agitating the cells on a solid surface of glass beads [70]. The expeller press through the application of a high mechanical pressure shatters and breaks the cells.…”

“…Intracellular heating causes water vapor, which disrupts the cells and subsequently opens the cell membrane [73]. In addition, the algicidal treatment exploits the capacity of some bacteria to attack and destroy target algae for the presence of hydrolytic enzymes able to break down the cell wall [70]. These techniques improve product recovery but are also potentially costly steps making biomass pretreatment an obstacle for large-scale production [16].…”

“…The fluorous solvents are colorless, are free-flowing liquid, and have low toxicity. Various types are available, the mainly used are perfluorinated alkanes, perfluorinated dialkyl polyethers, and perfluorinated trialkylamines [70].…”