Mandelate racemase interconverts the two enantiomers via a pathway that involves cleavage of the alpha-CH bond.

Derivatives of mandelic acid are formed as a result of metabolism of adrenaline and noradrenaline by monoamine oxidase and catechol-O-methyl transferase.

The biotechnological production of 4-hydroxy-mandelic acid and mandelic acid on the basis of glucose was demonstrated with a genetically modified yeast Saccharomyces cerevisiae, in which the hydroxymandelate synthase naturally occurring in the bacterium Amycolatopsis was incorporated into a wild-type strain of yeast, partially altered by the exchange of a gene sequence and expressed.

Mandelic acid has a long history of use in the medical community as an antibacterial, particularly in the treatment of urinary tract infections.

[13] It has also been used as an oral antibiotic, and as a component of chemical face peels analogous to other alpha hydroxy acids.