COMPETITIVE INHIBITION OF PROBIOTICS AGAINST METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS

Probiotics are beneficial for digestive system health; while methicillin-resistant Staphylococcus aureus (MRSA) is considered one of the most important causes of diarrhoea in developing countries. Therefore, the current study aimed to evaluate of antagonistic effect of probiotics against MRSA, thus, 100 samples of dairy products were collected from different local markets in Assiut City, Egypt, during the period from March 2022 to June 2023. The samples were divided into Baladi yoghurt, commercial yoghurt, Baladi Rayeb, commercial Rayeb and Ras cheese (each 20). The samples were placed into sterile plastic containers and transferred to the laboratory for isolation of probiotics and methicillin-resistant Staphylococcus aureus (MRSA). The antagonistic activity of probiotics supernatants against MRSA was investigated using the well diffusion agar method. The obtained results revealed that Lactobacilli species were isolated from 30% of the Baladi yoghurt samples, 30% of the commercial yoghurt samples, 50% of the Baladi Rayeb samples, 5% of the commercial Rayeb samples and 90% of the Ras cheese samples. While the MRSA was isolated only from the Ras cheese samples at a percentage of 5%. Regarding the antagonistic activity, Lactobacillus bulgaricus, Lactobacillus plantarum, Lactobacillus casei and Lactococcus cremoris strains showed an inhibitory effect against MRSA, while, MRSA was resistant to Lactobacillus acidophilus and Streptococcus thermophiles. In conclusion, supplementation of yoghurt with lactobacilli probiotics enhances quality and safety and increases Resistance against MRSA infection.