getpdf

Catalytic Properties of Lipase Extracts from Aspergillus niger

Licia M. Pera1*, Cintia M. Romero1, Mario D. Baigori1 and Guillermo R. Castro1,2


1
PROIMI, Av. Belgrano y Pasaje Caseros, 4000 Tucumán, Argentina

2Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA

Article history:

Received November 3, 2005
Accepted March 5, 2006

Key words:

lipase, Aspergillus niger, substrate specificity, solvent tolerance, thermoresistance, enzyme stability, lipase screening

Summary:

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 %.

 


*Corresponding author:     lymb@arnet.com.ar
                                         ++54 381 43 44 887

Search FTB


Follow us


 facebook 1 twitter bird_icon

 

QR Code


qrcode

We use cookies to improve our website and your experience when using it. Cookies used for the essential operation of the site have already been set. To find out more about the cookies we use and how to delete them, see our privacy policy.

I accept cookies from this site.

EU Cookie Directive Module Information