Use of Saccharomyces cerevisiae as a whole cell system for aldol condensation in organic medium: Study of the factors affecting the biotransformation

Saccharomyces cerevisiae has been employed as a whole cell catalyst for a number of asymmetric transformations. This work explores the ability of this microorganism to carry out the asymmetric aldol condensation between 4-nitrobenzaldehyde and acetone. For this purpose, lyophilized cells of the FY86 laboratory strain from stationary phase cultures were employed. This reaction shows stereoselectivity, and its progress is affected by the water concentration in the medium, temperature and the growth stage of the yeast culture. Cell lysis experiments indicate that activity responsible for this biotransformation is located in the soluble fraction.

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► Aldol condensation carried out by whole yeast cells is reported.
► Biotransformation of 4-nitrobenzaldehyde in acetone is shown to be stereoselective.
► Stereoselectivity is dependent on the temperature and water content in the medium.
► The growth stage of the yeast culture affects biotransformation.
► Component responsible of the aldol reaction is located in the yeast soluble fraction.