The production of biodiesel by transesterification employing acid or base catalyst has been industrially accepted for its high conversion and reaction rates. Downstream processing costs and environmental problems associated with biodiesel production and byproducts recovery have led to the search for alternative production methods. Recently, enzymatic transesterification involving lipases has attracted attention for biodiesel production as it produces high purity product and enables easy separation from the byproduct, glycerol. An indigenous microalgae Chlorella vulgaris grown in open pond cultivation obtained a high oil content of up to 14.72%. The microalgal oil was then converted to biodiesel by enzymatic transesterification directly using disrupted microalgal biomass was catalyzed by immobilized lipase, and the conversion rate reached up to 97.25%. In a word, the approach including high-density fermentation of Chlorella and enzymatic transesterification process were set up and proved to be a promising alternative for enzymatic biodiesel production.
