Biofilm Formation of Staphylococcus aureus under Food Heat Processing Conditions: First Report on CML Production within Biofilm

Abstract

This study aimed to evaluate the Staphylococcus aureus biofilm formation and Nε-carboxymethyl-lysine generation ability under food heat processing conditions including pH (5.0–9.0), temperature (25 °C, 31 °C, 37 °C, 42 °C and 65 °C), NaCl concentration (10%, 15% and 20%, w/v) and glucose concentration (0.5%, 1%, 2%, 3%, 5%, 10%, w/v). S. aureus biofilm genetic character was obtained by PCR detecting atl, ica operon, sasG and agr. Biofilm biomass and metabolic activity were quantified with crystal violet and methyl thiazolyl tetrazolium staining methods. S. aureus biofilm was sensitive to food heat processing conditions with 37 °C, pH 7.0, 2% glucose concentration (w/v) and 10% NaCl concentration (w/v) were favorable conditions. Besides, free and bound Nε-carboxymethyl-lysine level in weak, moderate and strong biofilm were detected by optimized high performance liquid chromatography tandem mass spectrometry. Nε-carboxymethyl-lysine level in S. aureus biofilm possessed a significant gap between strong, moderate and weak biofilm strains. This investigation revealed the biological and chemical hazard of Staphylococcus aureus biofilm to food processing environment.

Formation and Control of the Viable but Non-culturable State of Foodborne Pathogen Escherichia coli O157:H7

“…In recent years, E. coli has gradually developed into a health and safety issue of worldwide concern (Xu et al, 2007(Xu et al, , 2008a(Xu et al, ,b, 2011b(Xu et al, , 2016aYou et al, 2012;Lin et al, 2016;Miao et al, 2016Miao et al, , 2017aMiao et al, ,b, 2018Zhao et al, 2018a,b). The high incidence rate of E. coli in food products underlies the urgent need of appropriate strategies for early detection (Zhao et al, 2010b(Zhao et al, ,c, 2011(Zhao et al, , 2014(Zhao et al, 2018Wang et al, 2011;Xu et al, 2011cXu et al, , 2012bLin et al, 2017;Miao et al, 2017c;Liu et al, 2019;Miao et al, 2019). E. coli O157:H7, capable of producing Shiga toxin or Shiga-like toxin, can cause hemorrhagic colitis and hemolytic uremic syndrome in human beings (Neil et al, 2012).…”

Development and Application of a Simple “Easy To Operate” Propidium Monoazide-Crossing Priming Amplification on Detection of Viable and Viable But Non-culturable Cells of O157 Escherichia coli

“…In recent years, the outbreak of foodborne diseases caused by pathogens and its related virulence factors is a major threat for many countries, although much attention had been paid to food safety issues. Foodborne pathogens including enterohemorrhagic Escherichia coli (EHEC), Staphylococcus aureus , Vibrio parahaemolyticus , and Pseudomonas aeruginosa have posed great concern in the food industry and public health ( Miao et al, 2016 , 2019 ; Xie et al, 2017a ; Xu et al, 2019 ), especially their acquisition of antimicrobial resistance ( Xu et al, 2007 , 2011a , 2017b ; Yu et al, 2016 ; Xie et al, 2017b ; Liu et al, 2018c,d ), biofilm formation ( Lin et al, 2016 ; Bao et al, 2017a ; Miao et al, 2017b ), and toxin production ( Liu et al, 2016a ). EHEC causes more than 63,000 illnesses, 2,100 hospitalizations, and 20 deaths each year in the United States ( Jiang et al, 2016 ).…”

First Report on the Rapid Detection and Identification of Methicillin-Resistant Staphylococcus aureus (MRSA) in Viable but Non-culturable (VBNC) Under Food Storage Conditions

“…CPA assays were developed utilizing a visual method. As a novel nucleic acid amplification method, CPA assays are both successfully performed to detect MRSA if there is co-occurrence of S. aureus -specific femA and methicillin-resistance marker mecA ( Tacconelli et al, 2009 ; Miao et al, 2019 ). Since the invention of CPA technology, it has been employed for the detection of various bacteria.…”