Influence of Environmental Factors on Phage–Bacteria Interaction and on the Efficacy and Infectivity of Phage P100

Abstract

When using bacteriophages to control food-borne bacteria in food production plants and processed food, it is crucial to consider that environmental conditions influence their stability. These conditions can also affect the physiological state of bacteria and consequently host–virus interaction and the effectiveness of the phage ability to reduce bacteria numbers. In this study we investigated the stability, binding, and replication capability of phage P100 and its efficacy to control Listeria monocytogenes under conditions typically encountered in dairy plants. The influences of SDS, Lutensol AO 7, salt, smear water, and different temperatures were investigated. Results indicate that phage P100 is stable and able to bind to the host under most conditions tested. Replication was dependent upon the growth of L. monocytogenes and efficacy was higher when bacterial growth was reduced by certain environmental conditions. In long-term experiments at different temperatures phages were initially able to reduce bacteria up to seven log10 units after 2 weeks at 4°C. However, thereafter, re-growth and development of phage-resistant L. monocytogenes isolates were encountered.

Inhibitory Effect of Bacteriophages Isolated from Sewage Water in the City of Kirkuk on some Types of Human Pathogenic Bacteria

“…On other hand, failure to isolate bacteriophages specific to S. pyogenes might be a weird finding since bacteriophages are stable and widely distributed in environment. Like other viruses, bacteriophage virion or viral DNA can be affected by some external factors such as temperature, pH, and ionic strength [41,42]. Moreover, some authors even assume a relationship between phage morphology and its stability and diversity in the environment [43].…”

Isolation and Characterization of Bacteriophages against Escherichia coli Isolates from Chicken Farms

“…In the research of Coffey et al 2011, it was observed that phages e11/2 and e4/1c against E. coli reduced their viability to undetectable levels at pH 2, while phage survival was not significantly different at pH values between 3 and 10. Meanwhile, Fister et al (2016) demonstrated that phage P100 numbers were reduced below the detection limit at pH 2.0, and after 24 h at pH 4.0 viability was not significantly reduced. Although current research witnessed a rapid decrease in the number of phages that could survive in acidic pH conditions, there still was a presence of fourteen phages at pH 2.0 which could be used for the next investigation in the lytic activity of phages against E. coli strains.…”

Isolation, Characterization, and Application of Bacteriophages Against Several Food Spoilages Bacteria

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