Screening of commercial lipases for production of mono- and diacylglycerols from butteroil by enzymic glycerolysis

Eight microbial lipases and one animal tissue lipase were tested for their ability to support glycerolysis reactions with butteroil in the presence and absence of t-butanol to produce monoacylglycerols (MAG) and diacylglycerols (DAG). Two bacterial lipases from Pseudomonas spp. showed the greatest yield of MAG (55-60%) and DAG (24-39%) in the presence or absence of t-butanol. In contrast, lipases from Rhizopus arrhizus, R. javanicus and R. delemar produced yields of MAG and DAG of 23-25% and 36-39%, respectively, but were effective only in the absence of t-butanol. Porcine pancreatic lipase showed limited glycerolysis activity in the presence of t-butanol, yielding 4·6% MAG and 10% DAG, but was not active in the absence of t-butanol. Geotricum candidum, Muco javanicus and Candida cylindracea (C. rugosa) lipases did not support glycerolysis in the presence or absence of t-butanol. It appears possible to selectively use lipases from Pseudonomas and Rhizopus spp. to transform butteroil into blends of MAG and DAG with MAG:DAG ratios of about 0·65 to 2·3.