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

Recombinant alpha-L-rhamnosidase from Aspergillus terreus expressed in Pichia pastoris was immobilized in LentiKats (R) 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 alpha-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.