A novel feruloyl esterase with high rosmarinic acid hydrolysis activity from Bacillus pumilus W3

A novel feruloyl esterase (BpFae12) with rosmarinic acid (RA) hydrolysis activity was isolated from Bacillus pumilus W3 and expressed in Escherichia coli BL21 (DE3). With RA as a substrate, the optimal pH and temperature of BpFae12 were pH 8.0 and 50 °C, respectively. The specific enzyme activity was 12.8 U·mg^-1. BpFae12 showed the highest activity and substrate affinity toward RA (V_max of 13.13 U·mg^-1, K_m of 0.41 mM). Moreover, it also presented strong hydrolysis performance against chlorogenic acid (190.17 U·mg^-1). RA was effectively Hydrolyzed into more bioactive caffeic acid and 3,4-dihydroxyphenyllactic acid by BpFae12, which have potential applications in the food industry.