title: The effect of gamma-irradiation on the antibacterial activity of honey.
abstract: There is increasing usage of honey as a dressing on infected wounds, burns and ulcers, but there is some concern that there may be a risk of wound botulism from the clostridial spores sometimes found in honey. It is well-established that the antibacterial activity is heat-labile so would be destroyed if honey were sterilized by autoclaving, but the effect of gamma-irradiation on the antibacterial activity of honey is not known. Therefore an investigation was carried out to assess the effect on the antibacterial activity of honey when the honey was subjected to a commercial sterilization procedure using gamma-irradiation (25 kGy). Two honeys with antibacterial activity due to enzymically-generated hydrogen peroxide and three manuka honeys with non-peroxide antibacterial activity were investigated. The honeys were tested against Staphylococcus aureus in an agar well diffusion assay. There was no significant change found in either type of antibacterial activity resulting from this form of sterilization of honey, even when the radiation was doubled (to 50 kGy). Testing of honey seeded with spores of Clostridium perfringens and C. tetani (10000 and 1000 spores g-1 of honey, respectively) showed that 25 kGy of gamma-irradiation was sufficient to achieve sterility.
authors.affiliation: Department of Biological Sciences, University of Waikato, Hamilton, New Zealand.
authors.forename: P C
authors.initials: PC
authors.lastname: Molan
authors.forename: K L
authors.initials: KL
authors.lastname: Allen
mesh_terms: D006722:Honey / Q000382:microbiology / Q000528:radiation effects*; D006861:Hydrogen Peroxide; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus; D013242:Sterilization; D014946:Wound Infection / Q000382:microbiology
chemical_list: D006861:Hydrogen Peroxide