Inactivation of Escherichia coli and Vibrio parahaemolyticus on polypropylene plastic container surfaces by non-thermal dielectric barrier discharge plasma

We conducted a study on the antibacterial effect of dielectric barrier discharge plasma (DBDP) treatment on Escherichia coli and Vibrio parahaemolyticus, which cause food poisoning on the surface of polypropylene (PP) plastic containers. The initial concentrations of E. coli on PP plastic surfaces were 7.02 log CFU/coupon, and 6.50–5.37 log CFU/coupon in 5–60 min of DBDP treatment, respectively. In particular, the 60 min-treatment showed a high reduction of 1.65 log CFU/coupon (97.81% reduction). For V. parahaemolyticus, the control was 7.17 log CFU/coupon, with results of 6.81–6.13 log CFU/coupon in 5–60 min treatment, respectively. The D-values were 26.5 and 61.2 min, respectively (R2; 0.95 for E. coli, 0.96 for V. parahaemolyticus), showing significant differences (P < 0.05). The 60 min of DBDP treatment can be an eco-friendly sterilization method that reduces more than 90% of bacteria from the PP plastic surfaces and has no physical effect. Furthermore, it will able be effectively applied to plastic or food production industry through more diverse and extensive studies on surface sterilization of DBDP. Therefore, we suggest DBDP as a novel commercial sterilization strategy against pathogenic bacteria including E. coli and V. parahaemolyticus on polypropylene plastic surfaces.