Biodiesel Synthesis through the Non-Alcohol Route using the Immobilized Lipase Enzyme from Bacillus subtilis as Biocatalyst

Abstract

Biodiesel is one alternative energy that might be promising to substitute the petroleum-based fuel due to its biodegradability and less toxic level. Biodiesel can be synthesized through the non-alcohol route by substituting the alcohol with methyl acetate using lipase enzyme as the Biocatalyst, which may give less by-product during the reaction. In this research, lipase from Bacillus subtilis has been produced and prepared in a crude, dry and immobilized form. It is used as the Biocatalyst for biodiesel synthesis. Several variables were investigated for obtaining the optimum condition in producing biodiesel, including the form of lipase enzyme, the variation of molar ratio between oil and methyl acetate, and the enzyme concentration. The immobilized Bacillus subtilis lipase enzyme loading was also calculated to know how many percent of the lipase is successfully immobilized. The biodiesel produced using lipase from Bacillus subtilis will then be compared with the biodiesel produced using Candida rugosa commercial lipase. Based on the experimental, the immobilized lipase with 1:12 of oil to methyl acetate and enzyme concentration of 2% gives the highest biodiesel yield among the others, as much as 53.99%. This yield was higher than the biodiesel produced using Candida rugosa lipase. In conclusion, the immobilized lipase from Bacillus subtilis is one of the promising Biocatalyst for biodiesel production.