Optimization of Cell Disruption and Transesterification of Lipids from Botryococcus braunii LB572

Abstract

Several methods including microwave, Frenchpress, autoclave, bead-beating, ultrasonication, and osmotic shock were compared to identify the most effective microalgal cell disruption method. Botryococcus braunii LB572 was cultured in 5 L flasks containing JM medium mixed with oceanic sediment extract for 13 days. Among the methods tested, enhanced lipid extraction was achieved through microwave treatment (2450MHz, 1250W at 150°C for 20 min). Oleic (C18:1), linolenic (C18:3), and palmitic acids (C16:0) were found to be the major fatty acids among the C14-C24 acids from extracted lipid. In addition, the optimal conditions of transesterification were as follows: 70 mL of methanol, 6 mL of sulfuric acid, 8 mL of chloroform, and boiling at 100°C for 30 min; 85.4% of C14-C24 FAME and 78.5% of C16-C18 FAME were esterified from transesterifiable lipids.