Commercial ampholytes used for isoelectric focusing may interfere with bioactivity based purification of antimicrobial peptides.

BioRad's Rotofor system has been frequently used for the purification of proteins and smaller peptides such as bacteriocins. In this study, we report that some commercially available ampholytes used with the Rotofor isoelectric focusing system possess antimicrobial activity, which may interfere with the purification of bacteriocins and bacteriocin-like substances.