|BORCHARDT, TRACE - University Of Georgia|
|KEGGI, CHRISTIAN M - University Of Georgia|
|CHO, SOHYUN - University Of Georgia|
Submitted to: American Society for Microbiology General Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/2/2015
Publication Date: 6/2/2015
Citation: Humayoun, S.B., Hiott, L.M., Borchardt, T., Keggi, C., Cho, S., Jackson, C.R., Frye, J.G. 2015. Susceptibility of Salmonella enterica Isolates Associated with Meat and Poultry to 16 Chemicals Used as Sanitizers and Biocides. American Society for Microbiology General Meeting. May 30-June 2, 2015. New Orleans, Louisanna.
Technical Abstract: Chemical antimicrobial interventions are used to reduce contamination of the animal environment, processing equipment, and meat with foodborne bacteria like Salmonella. We evaluated Salmonella susceptibility to 16 of these compounds by determining the minimum inhibitory concentration (MIC) of each chemical for Salmonella isolates. Wild type Salmonella (n=24) originating from meat and poultry were assayed to determine their average MIC to each chemical. The chemicals included: Acidified Sodium Chlorite (ASC), Acetic acid (AA), Arsenite (ARI), Arsenate (ARA), Benzalkonium chloride (BC), Cetylpyridinium chloride (CC), Citric Acid (CA), 1,3 dibromo, 5,5 Dimethylhydantoin (DBD), Dodecyltrimethylammonium chloride (DC), Hexadecyltrimethylammonium Bromide (HB), Hexadecyltrimethylammonium Chloride (HC), Lactic acid (LA), Peroxyacetic acid (PXA), Sodium Hypochlorite (SHB), Sodium Metasilicate (SM), and Trisodium phosphate (TP). For the MIC assay, 106 cells/ml were used to inoculate 96 well plates containing two-fold serial dilutions of the chemicals. Plates were incubated at 37oC for 24 h and turbidity indicated growth. Assays were repeated three times. Three control stains of Salmonella resistant to DC were also tested. The range of MIC in µg/ml and the average MIC (Avg.) for the 24 wild type isolates to each compound: ASC =78 to 625 (Avg. 351), AA=820 to 1641 (Avg. 1221), ARA=55 to 438 (Avg. 196), ARI=10 to 316 (Avg. 100), BC =3 to 32 (Avg. 19), CC=4 to 78 (Avg. 36), CA=3125 to 10834 (Avg. 5568), DBD=781 to 1563 (Avg. 820), DC=20 to 625 (Avg. 176), HB=20 to 313 (Avg. 95), HC=20 to 313 (Avg. 77), LA= 2500 to 9000 (Avg. 4348), PXA 405 to 811 (Avg. 738), SHB=27750 to 215064 (Avg. 67858), SM= 2500 to 31250 (Avg. 12595) and TP= 7500 to 75000 (Avg. 29160). The Salmonella control strains resistant to DC grew at four two-fold higher concentrations of DC than the wild type strains. This study established Salmonella MICs to 16 compounds. Strains resistant to DC were detected by growth at higher concentrations as compared to wild type Salmonella. This study provides MICs for these compounds and an assay which can be used to screen Salmonella isolates for resistance to chemical interventions. The assay will be used in conjunction with antibiotic susceptibility assays to detect correlations between biocide and antibiotic resistance.