Correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate during ultrasonic treatment

Liyan Liu; Ruirui Xu; Lin Li; Bing Li; Xia Zhang; Ximei Zhang; Zhenbo Xu

doi:10.1016/j.micpath.2017.12.062

Correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate during ultrasonic treatment

Microb Pathog. 2018 Feb:115:154-158. doi: 10.1016/j.micpath.2017.12.062. Epub 2017 Dec 24.

Authors

Liyan Liu¹, Ruirui Xu², Lin Li¹, Bing Li¹, Xia Zhang¹, Ximei Zhang³, Zhenbo Xu⁴

Affiliations

¹ School of Food Science and Engineering, South China University of Technology, Guangzhou, 510640, China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou, 510640, China.
² School of Food Science and Engineering, South China University of Technology, Guangzhou, 510640, China.
³ School of Food Science and Engineering, South China University of Technology, Guangzhou, 510640, China. Electronic address: femzhang@scut.edu.cn.
⁴ School of Food Science and Engineering, South China University of Technology, Guangzhou, 510640, China; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou, 510640, China; Department of Microbial Pathogenesis, University of Maryland, Baltimore 21201, USA. Electronic address: zhenbo.xu@hotmail.com.

PMID: 29278782
DOI: 10.1016/j.micpath.2017.12.062

Abstract

Objective: This study aimed to investigate correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate (WPI) during ultrasonic treatment.

Methods: The structural changes of WPI under ultrasonic field were studied by amino-acid analyzer, circular dichroism, SDS-PAGE, and spectrophotometer.

Results: With the increasing of WPI concentration added during ultrasonic treatment, the survival rate of E. coli increased. The influence of WPI on bactericidal activity under ultrasonic treatment might due to the change of tertiary and higher level structures, not by the primary structure, and had little relation with secondary structure.

Conclusion: The influence of WPI on bactericidal activity during ultrasonic treatment might due to the change of the tertiary structure and higher level structures.

Keywords: Bactericidal activity; E. coli; Structure; Ultrasonic field; Whey protein isolate.

MeSH terms

Amino Acid Sequence
Anti-Bacterial Agents / pharmacology*
Escherichia coli / drug effects*
Protein Structure, Secondary
Ultrasonic Waves*
Whey Proteins / pharmacology*

Substances

Anti-Bacterial Agents
Whey Proteins