{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:56:37Z","timestamp":1792788997793,"version":"4.5.0"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,10,20]],"date-time":"2021-10-20T00:00:00Z","timestamp":1634688000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund (ERDF) through the Interreg V-A Spain-France-Andorra programme (POCTEFA 2014\u20132020, cofinancing rate 65%)","award":["INTERREG POCTEFA EFA183\/16\/OUTBIOTICS"],"award-info":[{"award-number":["INTERREG POCTEFA EFA183\/16\/OUTBIOTICS"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>According to the search for alternatives to replace antibiotics in animal production suggested in the antimicrobial resistance action plans around the world, the objective of this work was to evaluate the bactericidal effect of kaolin\u2013silver nanomaterial for its possible inclusion as an additive in animal feed. The antibacterial activity of the C3 (kaolin\u2013silver nanomaterial) product was tested against a wide spectrum of Gram-negative and Gram-positive bacteria (including multidrug resistant strains) by performing antibiograms, minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC), as well as growth inhibition curves against seven strains causing infections in animals. The C3 product generated inhibition halos in all the tested strains, and a higher activity against Gram-negative bacteria was found, with MBC values ranged from 7.8 \u00b5g\/mL (P. aeruginosa) to 15.6 \u00b5g\/mL (E. coli and Salmonella). In contrast, it was necessary to increase the concentration to 31.3 \u00b5g\/mL or 250 \u00b5g\/mL to eliminate 99.9% of the initial population of S. aureus ATCC 6538 and E. faecium ATCC 19434, respectively. Conversely, the inhibition growth curves showed a faster bactericidal activity against Gram-negative bacteria (between 2 and 4 h), while it took at least 24 h to observe a reduction in cell viability of S. aureus ATCC 6538. In short, this study shows that the kaolin\u2013silver nanomaterials developed in the framework of the INTERREG POCTEFA EFA183\/16\/OUTBIOTICS project exhibit antibacterial activity against a wide spectrum of bacteria. However, additional studies on animal safety and environmental impact are necessary to evaluate the effectiveness of the proposed alternative in the context of One Health.<\/jats:p>","DOI":"10.3390\/antibiotics10111276","type":"journal-article","created":{"date-parts":[[2021,10,20]],"date-time":"2021-10-20T07:05:57Z","timestamp":1634713557000},"page":"1276","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Antibacterial Activity of Kaolin\u2013Silver Nanomaterials: Alternative Approach to the Use of Antibiotics in Animal Production"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4455-8148","authenticated-orcid":false,"given":"Lara","family":"P\u00e9rez-Etayo","sequence":"first","affiliation":[{"name":"Department of Microbiology and Parasitology, University of Navarra, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Parasitology, University of Navarra, 31008 Pamplona, Spain"},{"name":"IdiSNA, Navarra Institute for Health Research, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9","family":"Leiva","sequence":"additional","affiliation":[{"name":"Microbiology Service, Cl\u00ednica Universidad de Navarra, University of Navarra, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda","family":"D\u00edez-Leturia","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Parasitology, University of Navarra, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alba","family":"Ezquerra","sequence":"additional","affiliation":[{"name":"ENOSAN Laboratories, 50018 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Lostao","sequence":"additional","affiliation":[{"name":"ENOSAN Laboratories, 50018 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8242-4496","authenticated-orcid":false,"given":"Ana Isabel","family":"Vitas","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Parasitology, University of Navarra, 31008 Pamplona, Spain"},{"name":"IdiSNA, Navarra Institute for Health Research, 31008 Pamplona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12917-019-2162-8","article-title":"Antibiotic resistance in porcine pathogenic bacteria and relation to antibiotic usage","volume":"15","author":"Holmer","year":"2019","journal-title":"BMC Vet. 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