Biocatalytic synthesis of the Green Note <i>trans</i>-2-hexenal in a continuous-flow microreactor

Abstract

The biocatalytic preparation of <i>trans</i>-hex-2-enal from <i>trans</i>-hex-2-enol using a novel aryl alcohol oxidase from <i>Pleurotus eryngii</i> (<i>Pe</i>AAOx) is reported. As O₂-dependent enzyme <i>Pe</i>AAOx-dependent reactions are generally plagued by the poor solubility of O₂ in aqueous media and mass transfer limitations resulting in poor reaction rates. These limitations were efficiently overcome by conducting the reaction in a flow-reactor setup reaching unpreceded catalytic activities for the enzyme in terms of turnover frequency (up to 38 s^-1) and turnover numbers (more than 300000) pointing towards preparative usefulness of the proposed reaction scheme.