Oil‐water interfacial activation of lipase for interesterification of triglyceride and fatty acid

Abstract

AbstractLipase usually has little interesterification activity in organic solvents, probably owing to the absence of an oil‐water interface. Lipases were processed in a two‐phase hydrocarbon‐water system that had an oil‐water interface. Crude lipase (from Rhizopus japonicus) in a buffer and a small volume of aliphatic hydrocarbon as an oil phase were mixed and then lyophilized to remove the aqueous and oil phases. The interfacially processed lipase has a remarkable interesterification activity in n‐hexane compared to crude native lipases. We postulate that this activation is caused by the oil‐water interface, i.e., the interface between hydrocarbon and water makes the lipase lid open and enables the lipase to work effectively in n‐hexane. Several different hydrocarbons were investigated as an oil phase, and n‐tetradecane was found to be the best for interesterification. Activated lipase was successfully inactivated in a water suspension without an oil‐water interface, and the inactivated lipase could be reactivated. We demonstrated that the oil (hydrocarbon)‐water interface induced reversible activation to lipase for interesterification.