Immobilization of a thermophilic solvent-stable lipase from acinetobacter baylyi and its potential for use in biodiesel production

Abstract

Lipase transesterification of triglycerides is an environmentally safe alternative to chemical processing during biodiesel production. However, the cost and low stability of this enzyme remains problematic for commercial production. In this study, a thermophilic-solvent stable lipase from Acinetobacter baylyi (ABL) immobilized on Sepabeads EC-OD showed improved solvent stability. The optimal reaction conditions of immobilized ABL were comparable with those of the suspended lipase. Immobilization of ABL resulted in a broader pH activity range and enhanced storage stability. Optimal conditions for transesterification of palm oil were 6-step methanol feeding, 1:4 oil/methanol molar ratios, 20% enzyme loading, and 4% water content for 24 h at 40 ° C. Conversions of oil feedstocks to biodiesel of between 13 and 93% were obtained. Reusability for transesterification of immobilized ABL was comparable to that of commercial lipases. This study found that immobilized ABL is one of the biocatalyst candidates for further development and application in enzyme-catalysed biodiesel synthesis.