Combination strategy using pure enzymes and whole cells as biocatalysts for the preparation of 2-hydroxyesters and lactones from 2-oxoglutaric acid

An innovative combination strategy that uses pure enzymes and whole microbial cells in the same process was used to prepare enantionterically pure 3-carboxyalkyl-gamma-butyrolactones and several alkyl esters of 2-hydroxyglutarates from 2-oxoglutaric acid. The method involves two consecutive biocatalytic steps. The first step, which converts the 2-oxoglutaric acid into the corresponding dialkyl esters, was catalyzed by a lipase. Then in the second step, by microbial reduction of the dialkyl-2-oxoglutarates, it is possible to obtain 3-carboxyalkyl-gamma-butyrolactones or 2-hydroxyesters depending on the length of the chain in the alkyl moiety of the esters and on the fresh or lyophilized status of the cells. (C) 2004 Elsevier Ltd. All rights reserved.