Purification and Characterization of Lipase from <i>Aspergillus flavus</i> PW2961 using Magnetic Nanoparticles.

Abstract

Lipase from Aspergillus flavus was purified in a single step purification using MnFeO4 magnetic nano particles to achieve a 20.53- fold purification with specific activity of 11.29 U/mg and a 59% recovery yield. SDS-PAGE of lipase showed a single pure band with corresponding molecular weight of 35 kDa. The optimal temperature and pH for the enzyme activity were 45°C and 7.0 respectively. Addition of olive oil (1 %w/v) enhanced pH stability of the lipase with 86% residual activity at pH 7.0 after 6 h of incubation while the lipase was thermostable with 79% residual activity after 4 h of incubation. The enzyme activity was enhanced by Ca²⁺, Mg²⁺ and Mn2+ while the presence of Cu²⁺, Co²⁺ and Zn²⁺ exhibited inhibitory effect on the enzyme. The study therefore presented lipase from Aspergillus flavus PW2961 with potential in industrial and biotechnological application.

Key words: Lipase, purification, Aspergillus flavus PW2961, magnetic nanoparticles