Original Scientific Article
Detection of enterotoxigenic potential of Staphylococcus aureus isolates from cheese samples with two different methods
Marija Ratkova Manovska*,
Mirko Prodanov,
Dean Jankuloski,
Pavle Sekulovski,
Katerina Blagoevska

Mac Vet Rev 2022; 45 (1): 27 - 33


Received: 21 September 2021

Received in revised form: 04 November 2021

Accepted: 08 November 2021

Available Online First: 12 January 2022

Published on: 15 March 2022

Correspondence: Marija Ratkova Manovska, ratkova.marija@fvm.ukim.edu.mk


The primary objective of our study was to detect the occurrence of enterotoxigenic Staphylococcus aureus in diverse types of cheese (cow’s milk cheese and mixed milk cheese) samples from R.N. Macedonia. Cheese samples were analyzed for enumeration and isolation of the S. aureus strains according to ISO 6888-1. We detected the toxigenic potential of the strains by the use of the Enzyme Link Fluorescent Assay VIDAS system, and we confirmed the presence of the SEs (sea, seb, sec, sed, see) genes by multiplex PCR. The results showed that out of 270 samples of cheese, coagulase-positive Staphylococcus (CPS) were detected in 27 (10%), and coagulase-negative staphylococci in five samples (1.8%). Biochemically, all 27 CPS samples were confirmed to be Staphylococcus aureus. With VIDAS SET2 test we confirmed that 11 isolates are producers of one of the toxins limited by the test. With the conventional PCR we confirmed genes in only 7 isolates. Most common detected gene was seb n=3 (42.8%), followed by sea n=2 (28.6%), and sec n=2 (28.6%). Additionally, sed and see genes were not detected in any of the S. aureus isolates. Discrepancies between the two test methods for detection of enterotoxigenic potential are not uncommon. The presence of viable Staphylococcus aureus cells that have enterotoxin potency demonstrates the importance of appropriate hygiene practices in the diary process and also the maintenance of the products in order to obtain a safe final product for the consumers.

Keywords: cheese, enterotoxigenic, Staphylococcus aureus, VIDAS SET2, PCR


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© 2022 Ratkova Manovska M. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors have declared that no competing interests exist.

Citation Information

Macedonian Veterinary Review. Volume 45, Issue 1, Pages 27-33, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2022-0010, 2022