{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T10:58:18Z","timestamp":1785236298337,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,3,31]],"date-time":"2021-03-31T00:00:00Z","timestamp":1617148800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2017YFC1600305"],"award-info":[{"award-number":["2017YFC1600305"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31802246"],"award-info":[{"award-number":["31802246"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Program of Guangzhou","award":["201804010207"],"award-info":[{"award-number":["201804010207"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The GRAS (generally recognized as safe) status of Enterococcus has not yet been authenticated, but enterococci, as probiotics, have been increasingly applied in human healthcare and animal husbandry, for instance as a dietary supplement, feed additive, or growth promotor. The food chain is the important route for introducing enterococci into the human gut. The pathogenicity of Enterococcus from probiotic products requires investigation. In the study, 110 commercial probiotic products used for human, animal, aquaculture, and plants were examined, among which 36 enterococci were identified, including 31 from Enterococcus faecium, 2 from E. faecalis, 2 from E. casseliflavus, and 1 from E. gallinarum. Strikingly, 28 of the 36 enterococci isolated from probiotics here did not mention the presence of Enterococcus in the labeled ingredients, and no Enterococcus isolates were found from 5 animal probiotics that were labeled with the genus. In total, 35 of the 110 products exhibited hemolysis, including 5 (10.6%) human probiotics, 14 (41.2%) animal probiotics, 8 (57.1%) aquaculture probiotics, and 8 (53.3%) plant probiotics. The detection rates of virulence factors associated with adhesion, antiphagocytosis, exoenzyme, biofilm, and other putative virulence markers (PVM) in 36 enterococci were 94.4%, 91.7%, 5.6%, 94.4% and 8.3%. Twenty-six of the 36 isolated strains exhibited biofilm formation ability, where 25 strains (69.4%) and one (2.8%) were strong and weak biofilm producers, respectively. We analyzed the resistance rates against erythromycin (97%), vancomycin and ciprofloxacin (8%), tetracycline (3%), and high-level aminoglycosides (0%), respectively. High detection rates of msrC\/lsaA (86%) and aac(6\u2032)-Ii (86%) were observed, followed by vanC (8%), tetM (3%). The Tn5801-tetM-like integrative conjugative element (ICE) was identified in E. gallinarum, exhibiting resistance to tetracycline (64 \u03bcg\/mL). Seven probiotic E. faecalis and E. faecium, as active ingredients in human probiotics, shared the same STs (sequence types) and were distinct from the STs of other contaminated or mislabeled enterococci, indicating that two particular STs belonged to native probiotic isolates. These findings advocate appropriate assessments of enterococci when used in probiotics.<\/jats:p>","DOI":"10.3390\/microorganisms9040726","type":"journal-article","created":{"date-parts":[[2021,3,31]],"date-time":"2021-03-31T10:24:33Z","timestamp":1617186273000},"page":"726","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["New Insights into the Virulence Traits and Antibiotic Resistance of Enterococci Isolated from Diverse Probiotic Products"],"prefix":"10.3390","volume":"9","author":[{"given":"Fengru","family":"Deng","sequence":"first","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunsheng","family":"Chen","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyu","family":"Zhou","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huiying","family":"Xiao","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianyu","family":"Sun","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6838-3779","authenticated-orcid":false,"given":"Yiqun","family":"Deng","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jikai","family":"Wen","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou 510642, Guangdong, China"},{"name":"Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S25","DOI":"10.1002\/j.1536-4801.2016.tb00033.x","article-title":"Probiotics for irriFIG bowel syndrome: Clinical data in children","volume":"63","author":"Giannetti","year":"2016","journal-title":"J. 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