What are described are compositions comprising a) one or more compounds of the formula (I) in which R is a straight-chain or branched saturated alkyl group having 5 to 11 carbon atoms or a straight-chain or branched mono- or polyunsaturated alkenyl group having 5 to 11 carbon atoms, and b) one or more substances selected from the group consisting of hydroxypyridones and their salts. The compositions are distinguished in particular by an advantageous antimicrobial activity.