Detection of enterotoxin-encoding genes in Staphylococcus aureus isolated from raw milk buffalo in Khuzestan province

Subject Areas : Food Science and Technology

Azadeh Moradi Farsani ¹ , Amir Shakerian ² , Ebrahim Rahimi ³ , Hasan Momtaz ⁴

1 - School of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
2 - Rahmatieh, 166
3 - , Dept. of Food Hygiene, School of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
4 - Prof, Dept. of Pathobiology, School of Veterinary Medicine ,Shahrekord Branch, Islamic Azad University, Shahrekord, Iran

Received: 2017-08-28 Accepted : 2018-04-14 Published : 2018-06-22

Keywords: Staphylococcus aureus, Khuzestan, Enterotoxin, Buffalo raw milk,

Abstract :

Milk provides an ideal medium for bacterial growth and can be quickly infected with a variety of bacteria. Staphylococcus aureus is one of the major milk-borne pathogens. Considering the importance of S. aureus enterotoxins in milk as one of the main sources of food poisoning, it is necessary to isolate and to investigate various enterotoxins in foods. The present study was an attempt to detect enterotoxin-encoding genes in S. aureus isolates obtained from buffalo raw milk in Khuzestan province. For this, 100 samples of buffalo milk were obtained from milk distribution centers in Khuzestan province in 2016. The samples were evaluated through microbial and molecular assays and the presence of enterotoxin-generating genes in S. aureus isolates. According to the results, 7 samples contained SEA enterotoxin gene, which accounts for the highest number and distribution percentage. Also, two samples had both SEA and SEB, 2 samples had both SEA and SEC enterotoxin genes, and 1 sample had four SEA, SEB, SEC and SEH enterotoxin genes, and two samples included both SEH and SEJ enterotoxins genes, and one sample included the SEJ enterotoxin gene and one sample included both SEH and SEC enterotoxin gene. The relatively high presence of Staphylococcal enterotoxins encoding genes and the potential role of enterotoxin in human food poisoning indicates the significant role of buffalo milk as one of the human infection sources and the necessity of taking measures to prevent primary and secondary milk contamination by this bacterium.

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