Microbial reduction of aromatic carboxylic acids

Several benzoic, cinnamic and phenylacetic acid derivatives were screened with 20 micro-organisms, mainly fungi, for the reduction of their carboxylic function. For all organisms several compounds were reduced in fairly good yields up to 80% to the corresponding alcohol. No general rule could be established, concerning the substitution pattern, as to which compounds were transformed to the alcohol. Generally the reactions were accomplished within 48-70 h. Only minor, if any, side products were detected. Dicarboxylic acids, such as phthalic or phenylglutaric acids and similar compounds could not be reduced by the microorganisms tested.