T2-08 Inactivation of Human Enteric Virus Surrogates on Stainless Steel Surfaces by Non-thermal Plasma

Monday, July 29, 2013: 10:45 AM
213D (Charlotte Convention Center)
Doris D'Souza, University of Tennessee-Knoxville, Knoxville, TN
Xiaowei Su, University of Tennessee-Knoxville, Knoxville, TN
David Golden, University of Tennessee-Knoxville, Knoxville, TN
Introduction: Non-thermal atmospheric plasma (cold-plasma) technology can effectively treat thermally-sensitive food products to reduce the incidence of foodborne bacterial disease outbreaks. When a gas passes through cold-plasma, the resulting reactive species (oxygen, ozone, and free radicals) formed by electron collision have antimicrobial effects against bacteria. However, cold-plasma application for the inactivation of foodborne noroviruses, the leading cause of non-bacterial gastroenteritis, needs to be investigated.

Purpose: The goal of this research was to determine the ability of non-thermal plasma to inactivate human enteric virus surrogates on stainless steel surfaces.

Methods: Cultivable human norovirus surrogates, feline calicivirus (FCV-F9) and murine norovirus (MNV-1), and bacteriophage MS2 at ~7 log plaque forming units (PFU)/ml were inoculated and dried on sterile stainless steel coupons. These coupons were treated with the patented One Atmosphere Uniform Glow Discharge Plasma for 0, 1, 2, 5, and 10 min. Recovered viruses were evaluated by plaque assays using their respective host cells and compared to untreated controls. Each experiment was replicated thrice in duplicate. Data was statistically analyzed using SAS at P < 0.05.

Results: Data obtained showed that FCV-F9 was the most sensitive among the tested viruses to cold-plasma treatment, followed by MS2 and MNV-1. FCV-F9 showed reduction of 2.34 and 3.55 log PFU after 1 and 2 min, respectively and to non-detectable levels after 5 and 10 min. MS2 was reduced by 2.03 and 5.46 log PFU after 2 and 5 min, respectively and to non-detectable levels after 10 min. MNV-1 was reduced by 0.56, 1.61, 1.95, and 3.16 log PFU after 1, 2, 5 and 10 min, respectively.

Significance: Non-thermal atmospheric plasma shows promise for use as an alternative disinfection technology against human enteric virus surrogates on stainless steel surfaces to prevent viral transmission. The technology has potential application for microbial inactivation on produce and other thermally-sensitive food products to prevent foodborne viral outbreaks.