title: Enteric Viral Surrogate Reduction by Chitosan.
abstract: Enteric viruses are a major problem in the food industry, especially as human noroviruses are the leading cause of nonbacterial gastroenteritis. Chitosan is known to be effective against some enteric viral surrogates, but more detailed studies are needed to determine the precise application variables. The main objective of this work was to determine the effect of increasing chitosan concentration (0.7-1.5% w/v) on the cultivable enteric viral surrogates, feline calicivirus (FCV-F9), murine norovirus (MNV-1), and bacteriophages (MS2 and phiX174) at 37 °C. Two chitosans (53 and 222 kDa) were dissolved in water (53 kDa) or 1% acetic acid (222 KDa) at 0.7-1.5%, and were then mixed with each virus to obtain a titer of ~5 log plaque-forming units (PFU)/mL. These mixtures were incubated for 3 h at 37 °C. Controls included untreated viruses in phosphate-buffered saline and viruses were enumerated by plaque assays. The 53 kDa chitosan at the concentrations tested reduced FCV-F9, MNV-1, MS2, and phi X174 by 2.6-2.9, 0.1-0.4, 2.6-2.8, and 0.7-0.9 log PFU/mL, respectively, while reduction by 222 kDa chitosan was 2.2-2.4, 0.8-1.0, 2.6-5.2, and 0.5-0.8 log PFU/mL, respectively. The 222 kDa chitosan at 1 and 0.7% w/v in acetic acid (pH 4.5) caused the greatest reductions of MS2 by 5.2 logs and 2.6 logs, respectively. Overall, chitosan treatments showed the greatest reduction of MS2, followed by FCV-F9, phi X174, and MNV-1. These two chitosans may contribute to the reduction of enteric viruses at the concentrations tested but would require use of other hurdles to eliminate food borne viruses.
authors.affiliation: Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Davis
authors.affiliation: Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996, USA.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Zivanovic
authors.affiliation: Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996, USA.
authors.forename: P Michael
authors.initials: PM
authors.lastname: Davidson
authors.affiliation: Department of Food Science and Technology, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996, USA. ddsouza@utk.edu.
authors.forename: Doris H
authors.initials: DH
authors.lastname: D'Souza
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000378:metabolism*; D010584:Bacteriophage phi X 174 / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D017927:Calicivirus, Feline / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D002460:Cell Line; D048271:Chitosan / Q000737:chemistry / Q000378:metabolism*; D004756:Enterobacteriaceae Infections / Q000517:prevention & control / Q000821:virology; D005503:Food Additives / Q000737:chemistry / Q000378:metabolism*; D005517:Foodborne Diseases / Q000517:prevention & control / Q000821:virology; D006801:Humans; D017909:Levivirus / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D008954:Models, Biological; D008970:Molecular Weight; D029322:Norovirus / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D012995:Solubility; D038301:Virus Inactivation; D018406:Virus Physiological Phenomena
chemical_list: D000998:Antiviral Agents; D005503:Food Additives; D048271:Chitosan
keywords: Antiviral; Chitosan; Enteric virus; Human norovirus