Lipid extraction from some seaweeds and evaluation of its biodiesel production

The present study evaluated the efficiency of seaweeds collected from Abu Qir Bay, Alexandria, Egypt, as a feedstock for biodiesel. A total of 15 macroalgal species were collected overall in the four seasons. The highest seasonal biomass production of 652.1 and 626.3 g m⁻² was recorded with Chaetomorpha linum and Ulva compressa in autumn and spring, respectively. While the highest annual biomass production was detected in Ulva fasciata (1056.8 g m⁻²). Lipid content varied among species, with the highest value of 14.66 % and 9.94 % dw in U. fasciata and U. compressa during spring, which resulted in the highest annual lipid productivity of 67.4 and 63.3 g m⁻², respectively. Palmitic acid (C16:0) showed the highest value among all fatty acids (1.12-19.62 mg g−¹ dw) in all studied species. The biodiesel characteristics of all algae species tested are in agreement with the values of international standards. Overall, the present study recommended U. compressa and U. fasciata as a promising biodiesel feedstock due to the relatively higher lipid productivity and FAMEs characteristics that comply with the international standards and high net energy output that reached 1.24 and 1.30 GJ ton⁻¹, respectively.