Antagonistic activity of Staphylococcus siderophores and chemical biocidesagainst Bacillus subtilis in a paper-machine environment

The antagonistic potential of nonpathogenic Staphylococcus strains against Bacillus subtilis wild and type strains were studied under conditions simul ating a paper- and board-machine environment. The antimicrobial activity wa s measured by growth inhibition in an automated turbidimeter. The antagonis tic potential was compared with that of generally used chemical biocides in a paper- and board-machine environment. The siderophore-containing extract s of Staphylococcus strains significantly inhibited vegetative growth of B. subtilis and delayed the germination of spores both in synthetic and in wh ite-water media. The mill strains were more resistant than type strain agai nst Staphylococcus siderophores and against chemical biocides. The Staphylo coccus siderophore-containing extracts did not interfere with the bacterios tatic effect of chemical biocides, but no synergy was detected. The results indicate the potential for application of Staphylococcus siderophore-conta ining extracts as biocontrol agents in paper- and boardmachine environment.