Occurrence and Antimicrobial Susceptibility of Listeria monocytogenes Isolated from Brined White Cheese in Jordan

Abstract

Listeria monocytogenes is a serious foodborne pathogen that has been isolated from different dairy food products. Several foodborne outbreaks of listeriosis have been associated with consumption of cheese. The aims of this study were to determine the occurrence of L. monocytogenes and Listeria spp. in brined white cheese (BWC) sold in Jordan, and to determine the susceptibility of isolated L. monocytogenes to antimicrobials. Three hundred and fifty samples of 5 different types of BWC (akkawi, boiled, halloumi, pasteurized, and shellal) were collected from a local market in Jordan. The ISO (11290-1) procedure was followed for isolation and identification of Listeria spp. from cheese samples and a polymerase chain reaction (PCR) technique was used for confirmation of L. monocytogenes isolates. The VITEK2 automated system was used for testing antimicrobial susceptibility of L. monocytogenes isolates. The overall prevalence of Listeria spp. in cheese sample was 27.1%. L. monocytogenes was isolated from 39 (11.1%) samples. Other isolated species were L. grayi (6.9%), L. innocua (2%), L. ivanovii (4%), L. seeligeri (2%), and L. welshimeri (0.3%). The pH values and salt concentrations of L. monocytogenes positive cheese samples ranged from 5.10 to 6.32 and 5.64 to 13.16, respectively. L. monocytogenes isolates were sensitive or intermediate susceptible to imipenem, gentamicin, linezolid, teicoplanin, vancomycin, fusidic acid, trimethoprim/sulfamethoxazole, benzylpenicillin, ciprofloxacin, erythromycin, tetracycline, and rifampicin, but resistant to fosfomycin, oxacillin, and clindamycin.

Isolation and Molecular Detection of Listeria monocytogenes in Minced Meat, Frozen Chicken and Cheese in Duhok Province, Kurdistan Region of Iraq

“…Our results were contradicted in another study conducted in Jordan by Osaili et al [19] who reported approximately 30% L. monocytogenes sample contamination rate. It should be noted that the contamination rate of Listeria in dairy products in our study was consistent with the results of [14].…”

Prevalence of Salmonella Serovars, Listeria monocytogenes, and Escherichia coli O157:H7 in Mediterranean Ready-to-Eat Meat Products in Jordan

“…Surprisingly, E. coli 0157:H7 was not isolated from any of these products, although this pathogen was isolated previously from raw beef in Jordan at a rate of 7.8% (30). The findings in the current study are promising in comparison with earlier reports on the prevalence of L. monocytogenes in RTE products in Jordan (29,32). In Amman, Osaili et al (29) found L. monocytogenes prevalences of 13.3, 76.7, and 30% in chicken shawirma, chicken burger, and chicken sausage, respectively.…”

“…Assessment of the food safety status and microbiolog ical quality of RTE foods available to consumers in Jordan is one of the major priorities for the Jordan Food and Drug Administration (JFDA), but few studies on the prevalence of foodbome pathogens in RTE food products in Jordan have been published (1,2,29,32). The objectives of the current study were to determine the prevalence Salmonella, L. monocytogenes, and E. coli 0157:H7 in Mediterranean RTE meat products sold in restaurants in Jordan and to determine the susceptibility of the isolates to selected antibiotics.…”

Isolation and Detection of Listeria monocytogenes in Minced Meat, Frozen Chicken and Cheese in Duhok Province, Kurdistan Region by using RT-PCR

“…In soft cheese about 1 (2%) out of 50 samples were found positive for L. Monocytogenes by PCR. Our results were contradicted to other study conducted in Jordan by Osaili et al [20] where they were reported about 30% of pathogenic L. monocytogenes in soft cheese. It should be noted that the pathogenic L. monocytogenes in our research for the contamination rate of Listeria in dairy products, cheese are consistent with the results indicated by Jalali and his team [16].…”