ANTIMICROBIAL RESISTANCE AND BIOFILM FORMATION OF SOME STAPHYLOCOCCUS SPECIES ISOLATED FROM TRADITIONAL CHEESES

Abstract

This research aimed to determine the occurrence of different Staphylococcus spp., in three types of Romanian traditional cheeses made of raw milk, and to establish their antimicrobial resistance profile. Additionally, we have also screened the biofilm forming capacity of the S. aureus isolates. Thus, 25 samples (cow telemea n = 10, sheep telemea n = 5, and cow ca? n = 10) were collected from local small producers that sell in urban fresh markets in Timi? county. A total of 64% (16/25) of the examined samples were positive. The bacterial strains were isolated on Mannitol Salt Agar (MSA) medium, then Baird-Parker medium was used to emphasize the coagulase activity. Furthermore, using the Vitek 2 Compact equipment, 17 strains were identified and included in 4 species of Staphylococcus genus, respectively one coagulase-positive (CPS) represented by Staphylococcus aureus 52.97% (9/17), and 3 coagulase-negative (CNS) comprised of S. epidermidis 23.52% (4/17), S. chromogenes 11.76% (2/17) and S. saprophyticus 11.76% (2/17). Disc diffusion method showed that the S. aureus isolates presented more resistance towards penicillin (100%), erythromycin, oxacillin, gentamicin, tetracycline (66.66%), and ciprofloxacin, clindamycin (55.55%). CNS isolates were more resistant towards penicillin (83.33%), erythromycin (66.66%), oxacillin (50), and tetracyclin (41.66%). From the total of 9 S. aureus, all were able to produce biofilms with absorbance at 570 nm.