Abstract: A proteineous component isolated from plant chromatin, after dissociation of the same, as an antimicrobial agent, the proteineous component having an apparent molecular weight between 10 and 20 kD. The proteineous plant component is produced by means of a method comprising the steps of homogenizing a plant material in order to expose its plant chromatin, dissociating the plant chromatin with a dissociating agent under hydrophobic conditions, and separating the dissociated plant chromatin into individual fractions, one comprising the proteineous plant component, by means of a hydrophobic interaction separation procedure.