The effect of temperature and length of heat shock treatment on the thermal tolerance and cell leakage of Cronobacter sakazakii BCRC 13988
Resource
International Journal of Food Microbiology, 134(3), 184-189
Journal
International Journal of Food Microbiology
Pages
184-189
Date Issued
2009
Date
2009
Author(s)
Chang, Chia-Hsiang
Chiang, Ming-Lun
Chou, Cheng-Chun
Abstract
Enterobacter sakazakii is an emerging opportunistic pathogen associated with life-threatening illnesses in infants, with infant formula serving as the principal mode of transmission. In the present study, C. sakazakii (formely E. sakazakii) BCRC 13988 was subjected to various heat shock treatments (42-48 °C for 5-15 min). Its subsequent survival at 51 °C and the leakage of intracellular materials was investigated. It was found that 47 °C was the maximum growth temperature of the test organism. In addition, heat shock enhanced the thermal tolerance of C. sakazakii BCRC 13988. Within heat shock temperatures between 42 and 47 °C, the thermal tolerance enhancing effect increased as the length or temperature of the heat shock treatment was increased. However, increasing the heat shock temperature to 48 °C reduced the thermal tolerance enhancing effect. Among the various heat shocked cells examined, the 47 °C-15 min-heat shocked C. sakazakii exhibited the highest thermal tolerance. Moreover, electron micrograph analysis showed that heat shock treatment caused damage and disruption in C. sakazakii cells. There was a significant increase (P < 0.05) in the leakage of nucleic acid and protein in the supernatant of the heat shocked cell suspension that increased as the temperature and duration of heat shock increased. ? 2009 Elsevier B.V. All rights reserved.
Subjects
Cell leakage; Cronobacter sakazakii; Heat shock; Thermal tolerance
SDGs
Other Subjects
article; bacterial growth; bacterial survival; bacterial viability; cell damage; controlled study; Enterobacter sakazakii; heat sensitivity; heat shock; heat stress; heat tolerance; nonhuman; temperature stress; Adaptation, Physiological; Colony Count, Microbial; Consumer Product Safety; Enterobacter sakazakii; Food Contamination; Food Handling; Food Microbiology; Hot Temperature; Humans; Infant; Infant Food; Infant Formula; Infant, Newborn; Microbial Viability; Time Factors; Enterobacter sakazakii
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
05.pdf
Size
24.16 KB
Format
Adobe PDF
Checksum
(MD5):dc1bf3a24df20bab04ec7733bd3c0d8e