Sublethal injury (SI) has been defined as “a consequence of exposure
to a chemical or physical process that damages but does not kill amicroorganism” More specifically, SI may affect cell wall or membrane permeability and also cause extensive damage to functional cell components SI is macroscopically detectable by the inability of injured survivors to formvisible colonies on media containing selective agents, e.g. sodium chloride, to
which healthy microbiota normally show resistance. Accordingly, the difference in plate counts between non-selective media, which support cell reparation before growth and represent both uninjured and injured cells, and the corresponding selective media, to which injured cells become sensitive, is a traditional means to quantify SI as a proportion or percentage of the entire population