Antibacterial Properties of Retail Sponges

Seven different brands of cellulose sponges and one polyurethane variety were evaluated for inhibitory properties on twelve strains of gram positive and gram negative bacteria. Sponges were cut in 13 mm or 17 mm discs, autoclaved and aseptically placed on inoculated Tryptic Soy agar plates. The inhibitory effects of sterile sponges, unrinsed, and rinsed in distilled water, were measured. The zone of inhibition values were based on the average of the diameters of the clear zones on the inoculated plates. Polyurethane and EXPANDING CELLULOSE SPONGES were the only varieties which did not exhibit antimicrobial properties with any of the selected bacterial strains. A thorough rinsing procedure was often insufficient to remove the inhibitory agents from the sponges. Listeria monocytogenes strain Scott A and Staphylococcus aureus , both gram positive, were strongly inhibited.