Performances of Free and Immobilized Frangipani (Plumeria Rubra) Latex Lipase in Palm Oil Lipolysis

摘要

Free fatty acid, which is an important intermediate product in the oleochemical industry, can be produced by hydrolysis of oil using lipase enzymes. This process is more economical and less energy consuming than the conventional process, i.e. noncatalytic thermal hydrolysis. While lipase from microorganisms requires a complex separation step, that from plants involves lower cost and easier handling. Nevertheless, no report has been published on the immobilization of plant latex-based lipase, while immobilization to increase the economic feasibility of microbial lipases has been widely reported. The aim of this study is to compare the performance of free and immobilized frangipani latex lipase in palm oil lipolysis. Immobilization was conducted by physical adsorption using hydrophobic supports and matrix encapsulation. The adsorption of frangipani latex lipase onto polypropylene and polyethylene beads was found to be ineffective, although the presence of the beads did slightly increase the degree of lipolysis. On the other hand, encapsulation with a calcium alginate matrix was effective in immobilizing particulate latex, although the calcium alginate beads were susceptible to breaking, causing contamination of the lipolysis product. To develop lipolysis technology utilizing frangipani latex lipase, free form lipase is more suitable in small-scale, stirred-tank lipolysis, while lipolysis with immobilized lipase from frangipani latex requires further modification, such as use of a packed bed reactor, circulated flow, or matrix modification.