Dewatering of Nannochloropsis Sp Via Forward Osmosis: A Molecular Dynamics Study

Microalgal biomass is an essential source of renewable energy and the production of high-valued bio-products. Nannochloropsis sp. is a marine microalgae which contains high valued bio-compounds. However, it contains elevated moisture which hinders extraction of important significant bio-compounds. A dewatering process of Nannochloropsis sp via forward osmosis is proposed. The objective of the study is to evaluate the effect of salinity on the lipid membrane of microalgae Nannochloropsis sp by inducing osmotic pressure difference. A microalgae lipid membrane model was developed using molecular dynamics and evaluated through relative structural changes and water dynamics by varying the salinity. The results revealed at elevated salinity, compression occurs to the lipid membrane based on the tail order and area per head groups. The dynamics of water molecules showed that water migration happens as early as 20 ns. Despite membrane compression, a total of 5 water molecules migrated within the 150 ns. This suggests that forward osmosis is a promising alternative for microalgal dewatering.