A study on the inactivation of micro-organisms and enzymes by high pressure CO2

✍ Scribed by Giulio Bertoloni; Alberto Bertucco; Veronica De Cian; Tiziana Parton

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 120 KB
• Volume: 95
• Category: Article
• ISSN: 0006-3592
• DOI: 10.1002/bit.21006

✦ Synopsis

Abstract

This study addresses some microbial inactivation phenomena induced by high pressure CO~2~ over micro‐organisms and enzymes. The activity of four selected enzymes was measured before and after treatment with CO~2~ under pressure in both buffer solutions and natural cellular environment (E. coli cells and tomato paste). Results are reported for acid phosphatase, alkaline phosphatase, ATPase, and pectinase at different conditions of temperature, CO~2~ pressure, and treatment time (32–40°C, 85–150 bar, 30–70 min). The results obtained show that the high pressure CO~2~ treatment induces an inactivation of cellular enzymatic activity higher than the one caused on the same enzymes in solution. However, the measured activity difference is not caused by a damage at the enzymes molecular level but is a consequence of the permeabilization of the cellular envelopes which leads to a release of unmodified enzymes from the cells with simultaneous drop of enzymatic cellular activity. The reported data suggest that the bacterial cell death is probably due not to a selective effect of high pressure CO~2~ treatment but to simultaneous detrimental action of CO~2~ on cellular membrane and cell wall. © 2006 Wiley Periodicals, Inc.