{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T14:30:11Z","timestamp":1788791411017,"version":"build-2803163510"},"reference-count":42,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T00:00:00Z","timestamp":1619568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deputyship for Research &amp; Innovation, Ministry of Education in Saudi Arabia","award":["375213500"],"award-info":[{"award-number":["375213500"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>This study evaluates bacteriological profiles in ready-to-eat (RTE) foods and assesses antibiotic resistance, extended-spectrum \u03b2-lactamase (ESBL) production by gram-negative bacteria, and heavy metal tolerance. In total, 436 retail food samples were collected and cultured. The isolates were screened for ESBL production and molecular detection of ESBL-encoding genes. Furthermore, all isolates were evaluated for heavy metal tolerance. From 352 culture-positive samples, 406 g-negative bacteria were identified. Raw food samples were more often contaminated than refined food (84.71% vs. 76.32%). The predominant isolates were Klebsiella pneumoniae (n = 76), Enterobacter cloacae (n = 58), and Escherichia coli (n = 56). Overall, the percentage of ESBL producers was higher in raw food samples, although higher occurrences of ESBL-producing E. coli (p = 0.01) and Pseudomonas aeruginosa (p = 0.02) were observed in processed food samples. However, the prevalence of ESBL-producing Citrobacter freundii in raw food samples was high (p = 0.03). Among the isolates, 55% were blaCTX-M, 26% were blaSHV, and 19% were blaTEM. Notably, heavy metal resistance was highly prevalent in ESBL producers. These findings demonstrate that retail food samples are exposed to contaminants including antibiotics and heavy metals, endangering consumers.<\/jats:p>","DOI":"10.3390\/ijerph18094718","type":"journal-article","created":{"date-parts":[[2021,4,28]],"date-time":"2021-04-28T22:29:07Z","timestamp":1619648947000},"page":"4718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Heavy Metal Tolerance Trend in Extended-Spectrum \u03b2-Lactamase Encoding Strains Recovered from Food Samples"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5328-4105","authenticated-orcid":false,"given":"Kashaf","family":"Junaid","sequence":"first","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Skaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6185-2042","authenticated-orcid":false,"given":"Hasan","family":"Ejaz","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Skaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1503-863X","authenticated-orcid":false,"given":"Iram","family":"Asim","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Molecular Genetics, The Women University, Multan 66000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4958-8629","authenticated-orcid":false,"given":"Sonia","family":"Younas","sequence":"additional","affiliation":[{"name":"Department of Pathology, Tehsil Headquarter Hospital Kamoke, Kamoke 50661, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1021-5481","authenticated-orcid":false,"given":"Humaira","family":"Yasmeen","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Molecular Genetics, The Women University, Multan 66000, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8680-8427","authenticated-orcid":false,"given":"Abualgasim Elgaili","family":"Abdalla","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Skaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3207-7216","authenticated-orcid":false,"given":"Khalid Omer Abdalla","family":"Abosalif","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Skaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8467-9692","authenticated-orcid":false,"given":"Ayman Ali Mohammed","family":"Alameen","sequence":"additional","affiliation":[{"name":"Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Skaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2312-3137","authenticated-orcid":false,"given":"Naveed","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8125-7972","authenticated-orcid":false,"given":"Syed Nasir Abbas","family":"Bukhari","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka 72388, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdul","family":"Rehman","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1156","DOI":"10.1089\/mdr.2017.0198","article-title":"Extended-Spectrum \u03b2-Lactamase, AmpC, and MBL-Producing Gram-Negative Bacteria on Fresh Vegetables and Ready-to-Eat Salads Sold in Local Markets","volume":"24","author":"Iseppi","year":"2018","journal-title":"Microb. 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