Multidrug Resistant Coagulase-Positive Staphylococcus aureus and Their Enterotoxins Detection in Traditional Cheeses Marketed in Banat Region, Romania

The main objectives of the present study were to determine the occurrence of coagulase positive staphylococci (CPS) and to assess the presence and antimicrobial susceptibility profile of Staphylococcus aureus isolates in different raw milk origin (cow and sheep) traditional cheeses marketed in Banat region, Romania. Additionally, the presence of mecA gene in S. aureus isolates and the staphylococcal enterotoxins (SEs) in cheese samples were evaluated. A total of 81.6% (138/169) of the screened samples were positive for CPS. Furthermore, 35.5% (49/138) of the investigated CPS positive cheese samples were contaminated with S. aureus, with an isolation frequency of 46.6% (14/30) in caș, 33.3% (32/96) in telemea, 25% (2/8) in burduf, and 25% (1/4) in urdă assortments, respectively. From the total number of S. aureus isolates, 6.1% (3/49) harbored the mecA gene. Detectable levels of SEs were identified in 4.3% (4/94) of cheese samples with a CPS contamination level higher than 105 log CFU g−1. The expressed antimicrobial susceptibility profile of the tested cheese-origin S. aureus isolates, with the automated Vitek 2 equipment, showed resistance towards amikacin (90.1%, 10 out from 11 tested), enrofloxacin (86.2%, 25/29), ceftiofur (72.7%, 8/11), neomycin (63.6%, 7/11), benzylpenicillin (53.1%, 26/49), kanamycin (41.4%, 12/29), rifampicin (39.5%, 15/38), tetracycline (38.8%, 19/49), tilmicosin (36.4%, 4/11), clindamycin (30.6%, 15/49), ciprofloxacin (30%, 6/20), erythromycin (22.4%, 11/49), tylosin (18.2%, 2/11), oxacillin (16.3%, 8/49), linezolid (15%, 3/20), teicoplanin (15%, 3/20), fusidic acid (13.1%), imipenem (10.5%, 4/38), vancomycin (7.9%, 3/38), ampicillin (5.5%, 1/18), mupirocin (5.5%, 1/18), fosfomycin (5%, 1/20), and gentamicin (4.1%, 2/49). Twenty-four (49%) S. aureus isolates exhibited multidrug resistance. The investigation highlighted a common occurrence of multidrug-resistant S. aureus strains in the monitored cheese assortments, which can constitute a potential risk for consumers’ health.

Effects of the drying method for flowers of Cynara cardunculus var. Altilis on milk coagulating properties

In the production of some traditional cheeses from vegetable rennet, raw extracts of Cynara cardunculus flowers are used as the coagulant. During the preparation of this rennet, there are many factors that can influence its coagulation activity. We studied the flowers of Cynara cardunculus var. altilis to evaluate the effects of some of these factors: ripening stage of the flower at harvest, type of drying, part of the flower subjected to drying, toasting of the pistils, and maceration time of the pistils. The results show that it is possible to improve the coagulation activity of the traditional preparation of Cynara cardunculus flowers through some practices such as the rapid drying of the flowers/pistils at a controlled temperature, the toasting treatment of the pistils carried out after the slow drying of the flowers, and the extension of the extraction time to 24 h.

Prevalence, Biotyping, and Antimicrobial Resistance of Yersinia enterocolitica Isolated from Traditional Iranian Cheeses - Evaluation of Yersinia enterocolitica in Traditional Cheeses

The present study aimed to investigate the contamination rate of various traditional Iranian cheese samples with Yersinia enterocolitica. In total, 200 cheese samples were collected from the northeast of Iran, and 10 types of traditional cheese were evaluated, including Lighvan, Kurdish, lactic, Tape-Salam, Onsory, Turkmen (type one and two), Sistani, Baluchi, and Kormange. The samples were analyzed using pre-enrichment Peptone-Sorbitol-Bile (PSB) broth, Yersinia selective agar (Cefsulodin-Irgasan-Novobiocin (CIN))following polymerase chain reaction (PCR). Antimicrobial tests were carried out using 13 antibiotics on all the positive samples. From the cheese samples collected from Khorasan Razavi province, Kurdish cheese had the highest contamination rate (9/20; 45%), while the lowest contamination rate was observed in Lighvan and Onsory cheese. Also, the most commonly identified biotype was biotype 1A (23/38; 61%). Y. entrocolitica was mostly susceptible to ciprofloxacin, tetracycline, gentamicin, chloramphenicol, cefotaxime, and ceftazidime, while resistant to ampicillin and amoxicillin.

Can cheese mites, maggots and molds enhance bioactivity? Peptidomic investigation of functional peptides in four traditional cheeses

Peptide sequences identified in four cheeses by LC-Orbitrap MS/MS.