Growth and survival characteristics of Salmonella enterica regarding antibiotic resistance phenotypes

Abstract Salmonella enterica is a foodborne pathogen that can cause zoonotic diseases. The aggravation of antibiotic resistant S. enterica has drawn wide attention. Understanding the behavior of antibiotic-resistant pathogens along food chain is important to risk assessment. The objective of this study was to describe the growth and survival characteristics of S. enterica strains and evaluate the correlation with the strains’ antibiotic resistance phenotypes. Strains isolated from food (n = 16), clinic (n = 8) and standard strain (n = 2) of various antibiotic resistant phenotypes were selected, of which half strains were S. Typhimurium and half were S. Enteritidis. The growth parameters under different temperatures (25, 30, 35 °C) were obtained by time-to-detection (TTD) method, the survival characteristics were evaluated by the viability after exposed to heat (55, 57.5, 60 °C) and acid (HCl, pH = 3.0). It was observed that the antibiotic-resistant strains were more heat sensitive than antibiotics-sensitive ones, although the difference was significant only at 57.5 °C. The multi-antibiotics resistant strains showed significant higher acid resistance than antibiotics resistant ones. No significant differences were observed on growth and inactivation characteristics between strains of different origins or serotypes. This study provides useful information for understanding the correlation of antibiotic resistance phenotypes with growth and survival characteristics in S. enterica.