TY - JOUR

T1 - Continuous oxyfunctionalizations catalyzed by unspecific peroxygenase

AU - Meyer, Lars-Erik

AU - Hauge, Bjørn Fogtmann

AU - Kvorning, Thomas Müller

AU - Santis, Piera De

AU - Kara, Selin

N1 - Funding information: S. K. gratefully acknowledges the Independent Research Fund Denmark (PHOTOX-f project, grant no. 9063-00031B) for the grant funding in the framework of Sapere Aude DFF-Starting Grant. The authors are thankful to Dr. Simona Serban and Dr. Alessandra Basso from Purolite Ltd. (Unit D, Llantrisant CF72 8LF, United Kingdom) for kindly donating the carrier material for the enzyme immobilization. L.-E. M. thanks Dr. Markus Hobisch (Aarhus University, Denmark) for many fruitful discussions regarding the ABTS assay and production of UPO.

PY - 2022/9/5

Y1 - 2022/9/5

N2 - Unspecific peroxygenase (UPO) has been shown to be a promising biocatalyst for oxyfunctionalization of a broad range of substrates with hydrogen peroxide (H 2O 2) as the cosubstrate. In this study, we used the UPO mutant PaDa-I from Agrocybe aegerita (AaeUPO) for the enantiopure synthesis of (R)-1-phenylethanol from ethylbenzene and transferred it into continuously operated reactors. While the free enzyme was applied in an enzyme membrane reactor (EMR), the enzyme was immobilized on the ECR8315F carrier material and used in a packed-bed reactor (PBR). Both systems were fully characterized (residence time distributions, RTD) and a standard test reaction, the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), was carried out in continuous operation. Throughout, we found 1.5- and 1.2-times higher experimental RTDs than theoretical RTDs for the EMR and PBR, respectively. The EMR showed simplicity of handling, but it could not withstand the demands of a robust continuous synthesis. Therefore, the focus was on the PBR. We optimized the reaction conditions and produced 272 mg of ABTS˙ +-radical in 6.9 days and achieved a space-time-yield (STY) of 0.68 g (L h) −1 and a productivity of 0.16 mg (L h) −1. Eventually, we demonstrated the oxyfunctionalization of ethylbenzene to (R)-1-phenylethanol in continuous operation for the first time in the literature with a STY of 0.97 g (L h) −1 and a productivity of 0.25 mg (L h) −1. Hydrogen peroxide was stoichiometrically converted and the system proceeded for 6.2 days and neither the overoxidation byproduct acetophenone, nor the (S)-enantiomer was detected.

AB - Unspecific peroxygenase (UPO) has been shown to be a promising biocatalyst for oxyfunctionalization of a broad range of substrates with hydrogen peroxide (H 2O 2) as the cosubstrate. In this study, we used the UPO mutant PaDa-I from Agrocybe aegerita (AaeUPO) for the enantiopure synthesis of (R)-1-phenylethanol from ethylbenzene and transferred it into continuously operated reactors. While the free enzyme was applied in an enzyme membrane reactor (EMR), the enzyme was immobilized on the ECR8315F carrier material and used in a packed-bed reactor (PBR). Both systems were fully characterized (residence time distributions, RTD) and a standard test reaction, the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), was carried out in continuous operation. Throughout, we found 1.5- and 1.2-times higher experimental RTDs than theoretical RTDs for the EMR and PBR, respectively. The EMR showed simplicity of handling, but it could not withstand the demands of a robust continuous synthesis. Therefore, the focus was on the PBR. We optimized the reaction conditions and produced 272 mg of ABTS˙ +-radical in 6.9 days and achieved a space-time-yield (STY) of 0.68 g (L h) −1 and a productivity of 0.16 mg (L h) −1. Eventually, we demonstrated the oxyfunctionalization of ethylbenzene to (R)-1-phenylethanol in continuous operation for the first time in the literature with a STY of 0.97 g (L h) −1 and a productivity of 0.25 mg (L h) −1. Hydrogen peroxide was stoichiometrically converted and the system proceeded for 6.2 days and neither the overoxidation byproduct acetophenone, nor the (S)-enantiomer was detected.

UR - http://www.scopus.com/inward/record.url?scp=85139940375&partnerID=8YFLogxK

U2 - 10.1039/d2cy00650b

DO - 10.1039/d2cy00650b

M3 - Article

VL - 12

SP - 6473

EP - 6485

JO - Catalysis science & technology

JF - Catalysis science & technology

SN - 2044-4753

IS - 21

ER -