3.3.2 pH value
In a liquid environment, changes in pH affect the surface charge
properties of bacteria through the isoelectric point theory[112]. When the pH in the fluid domain is greater
than the bacterial isoelectric point, the ionization of the carboxyl
groups of amino acids on the bacterial surface makes them negatively
charged; when the pH in the liquid environment is less than the
bacterial isoelectric point, the ionization of the amino groups of amino
acids on the bacterial surface makes them positively charged.
Sheng et al. [113] measured the adhesion of three
bacteria (Pseudomonas sp, D. desulfuricans, and D. Singaporeans, with
isoelectric points of 2.1, 3.5, and 2.7, respectively) to 316 stainless
steel (SS316) in different pH artificial seawater (ASW) environments, as
shown in Table 1.