Biocontrol of Shiga Toxigenic Escherichia coli O157:H7 in Turkish Raw Meatball by Bacteriophage

Abstract

With an Escherichia coli O157:H7 virulent bacteriophage, M8AEC16, biocontrol efficiency of phages on a highly risky, ready-to-eat, traditional delicacy food called raw meatball under different storage conditions was investigated. Phage, belonging to the Myoviridae family, was isolated from the wastewater of a local slaughterhouse and showed a broad lytic activity toward many E.coli O157:H7 strains with high efficiency of plating and O157 specificity. Our experimental study provided favorable results, with 0.69-2.09 log colony-forming unit (cfu)/g E.coli O157:H7 reductions in the first 5h of the replica trials. Major reductions of viable E.coli O157:H7 counts were observed in the beginning of the storage period, reaching up to 1.85 log cfu/g. Although a significant reduction in E.coli O157:H7 was observed with increased phage concentration, storage conditions had minor effect on efficiency of phage biocontrol. This is the first study in Turkey that investigates applicability of phage biocontrol for a traditional food model. Practical ApplicationsPhage addition in preparation stage of a very complex food model, ready-to-eat Turkish raw meatball, is a promising application in decontamination of Escherichia coli O157:H7. Although investigation of its genomic characteristics along with its stability to different food matrices must be completed for further use of the model phage M8AEC16, findings of this work were encouraging, as phages are valuable in biocontrol of important foodborne in this ready-to-eat Turkish delicacy.