Enzymatic synthesis of a statin precursor by immobilised alcohol dehydrogenase with NADPH oxidase as cofactor regeneration system

Statins inhibit the synthesis of LDL-cholesterol which is related to cardiovascular diseases. One of the key steps in the synthesis of the chiral side chain of some statins is the oxidation of the chlorolactol to chlorolactone. This oxidation has been performed by an alcohol dehydrogenase (ADH99) using a NADPH-oxidase (NOX) as a cofactor regeneration system. The reaction conditions were optimised obtaining high reaction yield (94.7 %), space time yield (4.6 g L-1 h(-1)) and biocatalyst yield (7.9 mg product mg(-1) biocatalyst). Both enzymes have been efficiently immobilised onto different supports (Eupergit (R) CM, Amino-agarose, Epoxy agarose-UAB, Purolite ECR8409 and ECR8415). ADH99 showed a stability improvement when immobilised. However, NOX did not show any significant stability enhancement. The most stable ADH99 immobilised derivative, ADH99-Epoxy agarose-UAB, was used to perform the oxidation, improving 1.5-fold both, the total amount of product produced and the biocatalyst yield compared to the ADH99 soluble form.