Image Analysis Based Quantification of Bacterial Volume Change with High Hydrostatic Pressure

Pilavtepe-Celik M., BALABAN M. O., ALPAS H., Yousef A. E.

JOURNAL OF FOOD SCIENCE, vol.73, no.9, 2008 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 73 Issue: 9
  • Publication Date: 2008
  • Doi Number: 10.1111/j.1750-3841.2008.00947.x
  • Journal Name: JOURNAL OF FOOD SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: high hydrostatic pressure, image analysis, microbial cell, scanning electron microscopy, volume, SCANNING-ELECTRON-MICROSCOPY, SALMONELLA-TYPHIMURIUM, LISTERIA-MONOCYTOGENES, CELL, PRESERVATION, RESISTANCE, PROTEINS
  • Middle East Technical University Affiliated: Yes

Abstract

Scanning electron microscopy (SEM) images of Staphylococcus aureus 485 and Escherichia coli O157:H7 933 were taken after pressure treatments at 200 to 400 MPa. Software developed for this purpose was used to analyze SEM Images and to calculate the change in view area and volume of cells. Significant increase in average cell view area and volume for S. aureus 485 was observed in response to pressure treatment at 400 MPa. Cell view area for E. coli O157:H7 933 significantly increased at 325 MPa, the maximum pressure treatment tested against this pathogen. In contrast to S. aureus, cells of E. coli O157:H7 exhibited significant increase in average view area and volume at 200 MPa. The pressure-induced increase in these parameters maybe attributed to modifications in membrane properties, for example, denaturation of membrane-bound proteins and pressure-induced phase transition of membrane lipid bilayer.