Izvorni znanstveni članak
Catalytic Properties of Lipase Extracts from Aspergillus niger
Licia M. Pera
; PROIMI, Av. Belgrano y Pasaje Caseros, 4000 Tucumán, Argentina
Cintia M. Romero
; PROIMI, Av. Belgrano y Pasaje Caseros, 4000 Tucumán, Argentina
Mario D. Baigori
; PROIMI, Av. Belgrano y Pasaje Caseros, 4000 Tucumán, Argentina
Guillermo R. Castro
; Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA
Sažetak
Screening of lipolytic strains using Rhodamine-B/olive oil plate technique allowed the selection of Aspergillus niger MYA 135. Lipase production in submerged culture containing 2 % olive oil was enhanced by more than 50 % compared to basal cultural conditions. Optimal catalytic conditions for olive oil-induced lipase 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 of the residual lipase activity against the pH were found. However, preincubation at either 37 or 40 °C caused an increase in the olive oil-inducible lipolytic activity. On the contrary, lipase residual activity decreases in the 30–55 °C range when it was produced in basal medium. Lipolytic extracts were almost not deactivated in presence of 50 % water-miscible organic solvents. However, water-immiscible aliphatic solvents reduced the lipase activity between 20 and 80 %.
Ključne riječi
Aspergillus niger; substrate specificity; solvent tolerance; thermoresistance; enzyme stability; lipase screening
Hrčak ID:
109862
URI
Datum izdavanja:
15.6.2006.
Posjeta: 2.386 *