Catalytic properties of lipase extracts frrom Aspergillus niger

LICIA M. PERA; CINTIA M ROMERO; MARIO BAIGORI; GUILLERMO CASTRO

FOOD TECHNOLOGY AND BIOTECHNOLOGY

FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY

Año: 2006 vol. 44 p. 247 - 252

1330-9862

Biocatalytic properties and stability of lipase extracts produced by Aspergillus niger MYA 135, during culture in the absence or presence of olive oil, were investigated. Lipase production in submerged culture containing 2% olive oil was enhanced by >50% compared to basal cultural conditions. Optimal catalytic conditions for olive oil-induced lipase activity were pH 6.5 and 30-35°C. These values were shifted to the acid region (4.0-6.5) and 35-37°C when lipase extract was produced under basal conditions. Slight changes in residual lipase activity as a function of pH were observed. Preincubation at either 37 or 40°C caused an increase in olive oil-inducible lipolytic activity. However, lipase residual activity decreased in the 30-55°C range when it was produced in basal medium. Lipolytic extracts remained almost undeactivated in the presence of 50% water-miscible organic solvents. However, water-immiscible aliphatic solvents reduced lipase activity by between 20 and 80%.