Extraction, purification and characterization of lipoxygenase from Pleurotus ostreatus

Abstract EN

Lipoxygenase was extracted from the cup of Pleurotus ostreatus (Jaq : Fr) oyster mushroom for the first time in Iraq, and purified homogeneously through precipitation with 40 % saturation of (NH4)2SO4 as a partial purification then loaded on DEAE-Cellulose (Diethyl amino ethyl Cellulose) ion-exchange chromatography column and then the highly active elution parts have been passed through gel filtration column with Sephacryl S-300 as a final purification with 804 (U / mg protein) specific activity, 11.32 fold of purification and 36.54 % yield .

The molecular weight of the enzyme was estimated to 74 KDa by gel filtration Sephacryl S-300 column and the isoelectric point for enzyme was 5.3.

The optimal pH for lipoxygenase activity and stability were 8 and 6-8.5 respectively, and the optimal temperature for the activity and stability of the enzyme were 30 and 10-45 respectively.

Also the activation energy necessary for Lipoxygenase to convert lionleic acid to product and for enzyme denaturalization were calculated to 9.674 and 28.087 Kilo calorie / mole respectively