Effects of Temperature Abuse on the Growth and Staphylococcal Enterotoxin A Gene (<i>sea</i>) Expression of<i>Staphylococcus aureus</i>in Milk

Babić, Milijana; Pajić, Marija; Radinović, Miodrag; Boboš, Stanko; Bulajić, Snežana; Nikolić, Aleksandra; Velebit, Branko

doi:10.1089/fpd.2018.2544

Cited by 13 publications

(5 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In agreement with the growth of staphylococci in milk, the expression levels of sea in the inoculated milk incubated at room temperature increased with time and were higher than those in milk incubated at 8 °C. A similar finding was reported by Babić et al (2019), wherein the growth rate, sea gene expression, and SEA production were affected by the type of milk, the storage time, and the storage temperature [ 28 ]. The sea gene was found to be located in a family of temperate bacteriophages [ 29 ].…”

Section: Discussionsupporting

confidence: 85%

Effect of Temperature on the Expression of Classical Enterotoxin Genes among Staphylococci Associated with Bovine Mastitis

et al. 2021

View full text Add to dashboard Cite

Staphylococcal food poisoning (SFP), caused by the contamination of staphylococcal enterotoxins, is a common foodborne disease worldwide. The aims of this study were: (1) to investigate classical staphylococcal enterotoxin genes, sea, seb, sec, sed, and see, among Staphylococcus aureus and coagulase-negative staphylococci (CNS) associated with bovine mastitis; (2) to determine the effect of temperature on the expression of classical staphylococcal enterotoxin genes in staphylococci in milk. The detection of classical staphylococcal enterotoxin genes was performed using S. aureus (n = 51) and CNS (n = 47). The expression of classical enterotoxin genes, including sea, seb, sec, and see, was determined during the growth of staphylococci in milk subjected to ultra-high-temperature processing at two different temperatures: 8 °C and room temperature. Classical staphylococcal enterotoxin genes were expressed more frequently in S. aureus (35.30%) than in CNS (12.77%). The sec gene was most frequently detected in S. aureus (29.41%) and CNS (6.38%). Moreover, the expression of sea and sec was significantly higher at room temperature than at 8 °C after 16 h of incubation (p < 0.05). These results emphasize the importance of maintaining the storage temperature of milk below 8 °C to reduce the risk of SFP.

show abstract

Section: Discussionsupporting

confidence: 85%

Effect of Temperature on the Expression of Classical Enterotoxin Genes among Staphylococci Associated with Bovine Mastitis

et al. 2021

View full text Add to dashboard Cite

show abstract

“…It is generally accepted that SE production constitutes a risk when S. aureus bacteria exceed a threshold of 10 5 S. aureus CFU/mL of milk during manufacture [ 33 , 34 ]. For example, the production of enterotoxins SEA and SEB are detected in milk when the count of S. aureus exceeds the critical level of 10 5 CFU/mL [ 35 ].…”

Section: Discussionmentioning

confidence: 99%

“…Many studies indicate that temperature and pH might also influence the expression of genes that code for the production of enterotoxins [ 36 , 37 ]. A study shows that the production of SEA can usually be detected at 10–45 °C and the yield of SEA increases with the increasing temperature [ 33 , 38 ]. A study indicated that the conditions for SEA production were pH of > 5.0 and aw of > 0.86 at temperatures of > 15 °C [ 36 ].…”

Section: Discussionmentioning

confidence: 99%

Co-Occurrence of Staphylococcus aureus and Ochratoxin A in Pasteurized Milk

Zhang

Song

et al. 2022

Toxins

View full text Add to dashboard Cite

Pathogens and mycotoxins are serious public health risks for humans and food safety in milk. This study concentrated on detecting Staphylococcus aureus and Ochratoxin A (OTA) in 210 pasteurized milk from ten urban Beijing districts to suggest the co-occurrence of S. aureus with toxin-producing genes and OTA in milk and the possible risk. S. aureus was identified by physiological and biochemical experiments and molecular biology experiments, and enterotoxin genes were identified by PCR. OTA was detected by LC-MS/MS. The study found 29 isolates of S. aureus, of which 17.24% had the sea gene encoding enterotoxin A. OTA was detected in 31 out of 120 samples and the maximum amount of detection was 18.8 μg/kg. The results of this study indicate that when failing to guarantee the cold chain, the presence of S. aureus with enterotoxin genes in milk will present a risk to food safety. Furthermore, the high detection rates and levels of OTA in milk suggest that OTA is a hidden risk. The co-occurrence of S. aureus and OTA in milk is a food safety concern and there is a need to control the occurrence of these two biohazards in milk.

show abstract

“…The relative level of expression for each gene was calculated using the comparative threshold cycle method after normalizing the expression level of the gene encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for E. coli O157:H7 and S. aureus and an 18S ribosomal RNA for C. albicans and A. flavus , which maintains a stable level of expression at all stages of growth [ 44 , 45 ]. The virulence factors of E. coli , S. aureus , C. albicans , and A. flavus were chosen for long polar fimbriae A (IpfA), Staphylococcal enterotoxin A (SEA), plasma membrane ATPase pump (PamA), and aflatoxin biosynthesis (AflaC, AflaO, AflaR), respectively [ 46 , 47 , 48 , 49 , 50 ]. Furthermore, the stress response genes, including cell wall-related gene and sigma factor of bacteria, were chosen, and measured the relative expression levels during each chitosan nanoparticle treatment [ 29 , 51 , 52 , 53 ].…”

Section: Methodsmentioning

confidence: 99%

Synthesis of Fully Deacetylated Quaternized Chitosan with Enhanced Antimicrobial Activity and Low Cytotoxicity

et al. 2022

View full text Add to dashboard Cite

Fully deacetylated quaternary chitosan (DQCTS) was prepared by replacing the carboxyl group of chitosan with a quaternary ammonium salt. The DQCTS was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and nuclear magnetic resonance (NMR). The antimicrobial activity of DQCTS was evaluated using the minimum inhibitory concentrations (MIC) methods and time-kill assay. DQCTS exhibited strong antibacterial and antifungal activity against Staphylococcus aureus, Escherichia coli O157: H7, Candida albicans, and Aspergillus flavus. Especially, the antifungal activity against C. albicans of DQCTS was greatly improved at 15.6 µg/mL of MIC and 31.3 µg/mL of minimum fungicidal concentration (MFC). Expression levels of virulence genes of microorganisms were also significantly decreased by DQCTS treatment, and the risk of virulence of microorganisms might be decreased. The result of the cytotoxic effect of DQCTS on human skin cells (HaCaT cells) indicated that the cytotoxicity of DQCTS on HaCaT cells was nearly non-toxic at 50 μg/mL. The DQCTS, with strong antimicrobial and low toxicity, has a high potential for use in functional food packaging and biomedical applications.

show abstract

Effects of Temperature Abuse on the Growth and Staphylococcal Enterotoxin A Gene (sea) Expression ofStaphylococcus aureusin Milk

Cited by 13 publications

References 25 publications

Effect of Temperature on the Expression of Classical Enterotoxin Genes among Staphylococci Associated with Bovine Mastitis

Effect of Temperature on the Expression of Classical Enterotoxin Genes among Staphylococci Associated with Bovine Mastitis

Co-Occurrence of Staphylococcus aureus and Ochratoxin A in Pasteurized Milk

Synthesis of Fully Deacetylated Quaternized Chitosan with Enhanced Antimicrobial Activity and Low Cytotoxicity

Contact Info

Product

Resources

About