Abstract: The present invention provides antimicrobial preparations of crystalline particles of an antimicrobial agent, wherein said antimicrobial agent is an antimicrobial peptide or an antimicrobial polyene, methods for preparing the same and uses thereof to combat microorganisms. The invention further provides crystalline particles of the antimicrobial agent so obtained from the methods of the invention in isolated form and concentrated liquid preparations which comprise said crystalline particles. The invention still further provides the use of such isolated crystalline particles and concentrated liquid preparations to combat microorganisms.