Production and purification of a novel extracellular lipase from Alternaria brassicicola

Alternaria brassicicola produced higher quantities (3.2 U/ml) of an inducible extracellular lipase (EC 3.1.1.3) in shaken synthetic medium supplemented with 20 mM methyloleate. After purification, the M r of the lipase was determined as 80 kDa by SDS-PAGE and estimated at 85 kDa using gel filtration, which suggest that the enzyme may be a monomer. The optimum pH and temperature for activity of the enzyme were 9.0 and 25ºC, respectively. Using umbelliferone esters, the lipase was shown highly specific towards a synthetic substrate with long-chain unsaturated fatty acid.