Effect of pressure-induced changes in the ionization equilibria of buffers on inactivation of Escherichia coli and Staphylococcus aureus by high hydrostatic pressure.

ABSTRACT: Survival rates of Escherichia coli and Staphylococcus aureus after high-pressure treatment in buffers that had large or small reaction volumes (ΔV°), and which therefore underwent large or small changes in pH under pressure, were compared. At a low buffer concentration of 0.005 M, survival was, as expected, better in MOPS (morpholinepropanesulfonic acid), HEPES, and Tris, whose ΔV° values are approximately 5.0 to 7.0 cm(3) mol(-1), than in phosphate or dimethyl glutarate (DMG), whose ΔV° values are about -25 cm(3) mol(-1). However, at a concentration of 0.1 M, survival was unexpectedly better in phosphate and DMG than in MOPS, HEPES, or Tris. This was because the baroprotective effect of phosphate and DMG increased much more rapidly with increasing concentration than it did with MOPS, HEPE

SUBMITTER: Gayan E 

PROVIDER: S-EPMC3697583 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature