Purification and characterization of extracellular lipase by Geotrichum candidum of dairy origin

摘要

In the present study, thermostable lipase from Geotrichum candidum UCMA 91(ATCC 204307) was purified andcharacterized. Lipase produced after optimization of the various cultural and physico-chemical conditions was purified tohomogeneity by two step methods of purification: ammonium sulfate precipitation and column chromatography. Theenzyme was purified by 60% ammonium sulfate precipitation and lipase activity of 5.77U mg-1 was attained. Then,Sephadex G-75 was used for gel filtration chromatography and 62.36fold purification was achieved. Molecular mass oflipase was estimated to be 59 KDa by using SDS-PAGE. It is also determined from the study that lipase showed stability atvarying range of pH (5-12) and thermo stability (15-65oC). The lipase was completely inhibited by EDTA (3.98%)confirming it as a metalloprotease, whereas the enzyme was found to be stable in various organic solvents. The resultsdemonstrate that lipase hydrolyzes vegetable oils, which validates its technological relevance for use in the dairy,pharmaceuticals and bakery industry.