Synergistic Effects of Lactic Acid and Sodium Dodecyl Sulfate to Decontaminate Escherichia coli O157:H7 on Cattle Hide Sections

Abstract The objective of this study was to investigate the antibacterial properties of chitosan acetate (CA), sodium dodecyl sulfate (SDS), lactic acid (LA) and their synergism when combined against a nontoxigenic strain of Escherichia coli O157:H7. Treatments that significantly reduced the concentration of E. coli O157:H7 in vitro by more than two logs were further investigated using a cattle hide decontamination model. In vitro treatments included CA (1% chitosan in 1% acetic acid vol/vol), SDS (1% vol/vol), SDS (2% vol/vol), LA (1% vol/vol), CA-SDS combination (1% chitosan in 1% acetic acid vol/vol mixed with 1% SDS vol/vol), and LA-SDS combination in two different concentrations (1% LA mixed with 1% SDS vol/vol, and 1% LA mixed with 2% SDS vol/vol). Butterfield's Phosphate Buffer water was used as a control. The antibacterial effect of 1% CA solution alone and in combination with 1% SDS in vitro resulted in a 1.8 and 1.7 log colony-forming units (CFU)/mL reduction, respectively (p<0.05). Only 1% LA, ...