Unspecific peroxygenases immobilized on Pd-loaded three-dimensional ordered macroporous (3DOM) titania photocatalyst for photo-enzyme integrated catalysis

The selective oxyfunctionalization of C-H and C C bonds is highly important and catalyzed by unspecific peroxygenases (UPOs) which suffer from inactivation by hydrogen peroxide (H 2 O 2 ). Herein, photo-enzyme integrated catalysts were constructed by immobilizing Aae UPO as cross-linked enzyme aggregates (CLEAs) in Pd-loaded three-dimensional ordered macroporous titania (3DOM TiO 2 ) with in situ photocatalytic H 2 O 2 production. The prepared Aae UPO@3DOM TiO 2 -Pd obtained higher catalytic efficiency compared with CLEAs- Aae UPO. The conversion of ethylbenzene to (R) -1-phenethyl alcohol was significantly improved, reaching 99 % compared with free enzyme (38 %) and CLEAs- Aae UPO (49 %), with ee value of > 99 %. Aae UPO@3DOM TiO 2 -Pd exhibited good stability and reusability attributed to the protection of macropores and in situ H 2 O 2 production. By using the designed 3DOM platform for photocatalysis and enzyme immobilization, the in situ photocatalytic generation of H 2 O 2 was highly efficient, and the monodisperse CLEAs- Aae UPO in the macropores facilitated the contact of substrate and enzyme, thus obtaining excellent photo-enzyme coupled catalysis.