Combination of cell disruption method and pH variation as pre-treatment for lipid extraction of Nannochloropsis sp.

Abstract

The quantity of fossil-based fuel also has depleted due to over-exploitation. Therefore, environmentally friendly and more sustainable energy resources are being searched to fill in the energy supplies in the future. Microalgae have been considered by the researcher as alternative biofuel feedstock due to their high lipid content. Lipid extraction is one of the crucial steps in biofuel production from microalgae. The aim of this study was to analyze the best combination of pre-treatments to obtain microalgae lipid for biodiesel. The utilization of different cell disruption methods, including sonication and microwave, combined with pH variation (3, 5, 7) was implemented on microalgae Nannochloropsis sp. The experiment shows cell disruption with sonication and combined with low pH 3 of oil extraction from Nannochlorpsis sp. resulted in the highest yield of oil content (1.15% gr/gr dry weight). The lipid extracted from each pH pre-treatment were analyzed using GCMS for its fatty acid profile. The best pretreatments combination was obtained from lipid extraction from pH 5 and sonication-assisted method.