Expression of Aspergillus oryzae tannase in Pichia pastoris and its application in the synthesis of propyl gallate in organic solvent.

Summary Gallic acid esters could be synthesized biologically by tannase in organic media, among which is propyl gallate, an antioxidant widely used as a food additive. Efficient intracellular expression of Aspergillus oryzae tannase was achieved in Pichia pastoris under the control of the AOX1 promoter, and the productivity of recombinant tannase was 960 U/L or 64 U/g dry mass. The recombinant P. pastoris was used to synthesize propyl gallate in organic solvent and the yield of propyl gallate was 53 %.