Efficient production of peracetic acid in aqueous solution with cephalosporin-deacetylating acetyl xylan esterase from Bacillus subtilis

Peracetic acid (PAA) is widely used in sterilization, bleaching textile industry, environmental engineering, chemical synthesis, and biomimetic chemistry. A previous study reported that acetyl xylan esterase (AXE) of Bacillus subtilis CICC 20034 has high activity toward cephalosporin C and 7-aminocephalosporanic acid. In this study, we found that AXE also exhibited high perhydrolysis activity toward acetate esters and endowed itself with great industrial interest on enzyme-catalyzed preparation of PAA. Recombinant AXE of B. subtilis CICC 20034 could be efficiently produced in a low-cost autoinduction medium with an activity of 6.8 × 10³ U/mL. The reaction conditions for the optimal synthesis of PAA were as follows: 0.30 mg/mL AXE crude enzyme, 300 mM glycerol triacetate, and 1 M hydrogen peroxide, pH 8.0, and 20 °C, which produced approximately 150 mM of PAA within 5 min. The AXE was then immobilized on an acrylate amino resin; the activity of the immobilized AXE was 383.7 U/g. In the presence of 1 g/mL of immobilized AXE resin, PAA titer of the initial reaction batch was approximately 142.5 mM, and about 95.5 mM of PAA could be produced after 10 cycles.