Recombinant α-L-rhamnosidase of Aspergillus terreus immobilization in polyvinylalcohol hydrogel and its application in rutin derhamnosylation

Abstract

Recombinant α-L-rhamnosidase from Aspergillus terreus expressed in Pichia pastoris was immobilized in LentiKats^® lens-shaped polyvinylalcohol (PVA) capsules with an activity of 7 U g^{− 1}, which was 21% of its original activity. Immobilization did not significantly affect the pH and temperature profile of α-L-rhamnosidase, K_M increased by a factor of 3.4 whereas V_max decreased more than 10-fold. No decrease in activity was observed after 27 repeated batch runs of rutin derhamnosylation. The enzyme proved to have an excellent storage stability (136 days) in 60 g L^{− 1} ethanol with no change in its activity.

Keywords::

• α-L-rhamnosidase
• Aspergillus terreus
• immobilization
• polyvinyl alcohol gel
• isoquercitrin

Declaration of interest The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.

The research leading to these results has received funding from the European Union Seventh Framework Programme BIONEXGEN (FP7/2007-2013) under grant agreement n° 266025. This work was co-funded by the Slovak Research and Development Agency under the contract No. DO7RP-0042-11 and by Ministry of Education of the Czech Republic contract No. 7E11010.