Abstract

Biodiesel production from Nannochloropsis oculata oil using immobilized lipase with methyl acetate as an acyl acceptor

Author(s): D.Surendhiran,M.Vijay

The present investigation dealt with conversion of marine microalgal oil from Nannochloropsis oculata, to biodiesel, using immobilized lipase along with methyl acetate as acyl acceptor. Lipase, a versatile biocatalyst in biotechnological process, was isolated from Burkholderia cepacia MTCC4684. The crude extract of enzyme was entrapped in alginate beads. Using immobilized lipase the biodiesel conversion (%) was evaluated by optimizing the process parameters. The conditions yielding maximum conversion were 3g immobilized lipase, 1:12 oil to methyl acetate ratio, 350C, 6% water, 60 h reaction time and agitation rate of 400rpm. The immobilized beads retained their stability even after repeated uses of 20 cycles. The optimal conditions gave 95.36%of biodiesel conversion. The fatty acids predominantly constituting FAME (Fatty acid methyl esters), analysed usingGC-MS,were lauric (C12:0), palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2) and arachidic (C20:0) acids. Due to high content of oleic acid, biodiesel could be resistant to oxidation and stored for a longer period. This study is, thus an ecofriendly “green process”, involving reusable and potential immobilized biocatalyst for biodiesel production.