Optimization study of lipase from lactic acid bacteria and synthesis of flavor esters

Abstract

Lipases play a very important role as natural biocatalysts catalyzing several biochemical reactions. There has been an increased demand for microbial lipases due to inability of plant and animal lipases to meet the global requirement. The current focus of the study was intended to isolate hyperactive lipase producing strains using low cost substrates. The physical parameters for production of lipase from the selected strains were optimized by both classical and statistical methods, followed by cloning and expression to further improve the yield. The structure-function relation can be well understood by cloning and sequencing which helps in search for different sources of lipase for various biotechnological applications. Finally the expressed lipase was immobilized for esterification reactions for producing short chain fatty acids which can be used as flavor agents in food industries. newlineIn the present study, the best possible combinations of lipase producing Lactic acid bacteria were selected. Different single cultures like Lactococcus lactis, Lactobacillus brevis, Lactobacillus plantarum and co-cultures like Lactococcus lactis + Lactobacillus brevis, Lactococcus lactis + Lactobacillus plantarum and Lactobacillus brevis + Lactobacillus plantarum were studied for the optimum production of lipase using olive oil as substrate. newlineThe optimum conditions for maximum activity of different lactic acid bacterial lipase were investigated. The lipase activity with classical method of optimization was 32 U/ml from co-culture of Lactococcus lactis + Lactobacillus brevis, 35 U/ml for Lactococcus lactis + Lactobacillus plantarum and 37 U/ml for Lactobacillus brevis + Lactobacillus plantarum whereas with the statistical optimization the activity was found to be 33.5 U/ml from co-culture of Lactococcus lactis + Lactobacillus brevis, 36 U/ml from Lactococcus lactis + Lactobacillus planatrum and 38.5 U/ml for Lactobacillus brevis + Lactobacillus plantarum which showed 2vfold increase in the lipase production.