Purification and characterization of a hydrolysis‐resistant lipase from Aspergillus terreus

Abstract

Lipase from Aspergillus terreus was purified to homogeneity using ammonium sulfate precipitation and chromatographies with Q-Sepharose and Sephacryl S-200. It showed a single band on SDS-PAGE and IEF-PAGE with a relative molecular mass of 37.2 kDa and pI of 3.2. Its glycoprotein nature was confirmed with the percentage of saccharides of 5.02% and 3.88% determined by the phenol/sulfuric acid and anthrone/ sulfuric acid methods, respectively. The lipase hydrolyzed both plant oils and animal oils, with the K(m) value for substrate p-NPP of 16.42 mM at pH 6.0, 50 °C. The enzyme was tolerant in a wide range of pH (pH 3-12) with optimum activity at pH 4.0. It remained stable under the highest temperature of 65 °C, with maximal activity at 50 °C. Ca²⁺, Co²⁺, Mn²⁺, and Ni²⁺ stimulated enzyme activity, but Hg²⁺ caused inhibition. Detected detergents had no obvious effect on enzyme activity, except SDS, which stimulated the activity at lower concentrations but inhibited the activity at higher concentrations. The inhibitory effect on enzyme activity of phenylmethanesulfonyl fluoride revealed that the Ser was involved in catalysis. Saccharides had no obvious effect on enzyme activity but could enhance its thermostability. Furthermore, the enzyme was resistant to trypsin digestion.

Immobilization of Aspergillus terreus lipase in self-assembled hollow nanospheres for enantioselective hydrolysis of ketoprofen vinyl ester

“…The purification of Aspergillus terreus lipase (A. terreus lipase) was performed according to a previously reported method (Shi et al, 2013). The purified lipase was analyzed by SDS-PAGE (polyacrylamide gel electrophoresis).…”

Screening, purification, and characterization of an extracellular lipase from Aureobasidium pullulans isolated from stuffed buns steamers

“…A variety of techniques have been employed for lipase purification, e.g. precipitation, ultrafiltration, gel filtration, ion exchange chromatography, hydrophobic interaction chromatography, and affinity chromatography (Saxena et al, 2003;Ramani et al, 2010;Shi et al, 2014). Generally, the more techniques or steps used, the less enzyme recovery is obtained; therefore, the selection of purification approaches is practically significant.…”

“…The two non-ionic surfactants, Tween 20 and Tween 80, greatly enhanced the activity by almost 2-fold. However, the results from research investigating the influence of these two surfactants on lipases are conflicting, which may be due to the different concentrations the researchers used or the discrepancy of the lipase's nature (Kanjanavas et al, 2010;Shi et al, 2014). Another non-ionic surfactant, Triton X-100, also enhanced the lipase activity, but to a lesser extent.…”

Aspergillus Lipases: Biotechnological and Industrial Application

“…Lipase from Aspergillus has also been reported. Lipase from A. terreus hydrolyzed both animal and plant oils and was tolerant in a wide range of pH (pH 3-12), and it remained stable under the highest temperature of 65 C. There was no change on enzyme activity with the addition of detergents, except SDS that stimulates enzymatic activity [123]. The lipase from A. niger MTCC 2594 was isolated and showed pH stability between pH 4.0 and 10.0 and temperature stability between 4 C and 60 C. Furthermore, in the presence of SDS, Tween 80 and commercial detergents such as Henko and Surf Ultra improved the enzymatic stability [124].…”