{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T12:26:28Z","timestamp":1791462388392,"version":"4.3.4"},"reference-count":50,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T00:00:00Z","timestamp":1756771200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agricultural Education Division of Indian Council of Agricultural Research (ICAR), Ministry of Agriculture, Government of India"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Bacteriophage therapy can successfully provide additional treatment to control Salmonella infection, but low gastric pH limits its oral application. The present study aimed to develop an improved encapsulation formulation with enhanced acid protection for oral delivery of Salmonella phages using polymers. This was achieved by encapsulating a phage cocktail containing three different bacteriophages against Salmonella sp. in alginate beads incorporating polyvinyl alcohol (PVA), PVP-K30, and calcium carbonate as viscosity modifiers and acid protection enhancers. Further, the beads were coated with poly-L-lysine to improve the stability and tested for their efficacy for improved phage viability under in vitro acidic conditions for subsequent use in oral delivery. Moist beads were slimy, and semi-dried beads presented a coarse surface as observed using FE-SEM. In vitro studies revealed that the free phage cocktail exhibited complete inactivation when exposed to acidic pH 2.5 after 15 min incubation. In contrast, the encapsulated phage cocktail showed a decrease of only 1.66 log units in viability when incubated for 90 min at pH 2.5. Furthermore, oral delivery of the encapsulated phage cocktail in the poultry model significantly reduced bacterial load in infected birds\u2019 intestines.<\/jats:p>","DOI":"10.3390\/v17091205","type":"journal-article","created":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T12:04:28Z","timestamp":1756814668000},"page":"1205","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Development of an Acid-Protective Polymer Encapsulation Formulation for Oral Delivery of Salmonella Phages"],"prefix":"10.3390","volume":"17","author":[{"given":"Manju","family":"Bernela","sequence":"first","affiliation":[{"name":"ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5575-3307","authenticated-orcid":false,"given":"Nitin","family":"Virmani","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9134-0737","authenticated-orcid":false,"given":"Bidhan Chand","family":"Bera","sequence":"additional","affiliation":[{"name":"National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7554-5238","authenticated-orcid":false,"given":"Rajesh Kumar","family":"Vaid","sequence":"additional","affiliation":[{"name":"National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9896-1891","authenticated-orcid":false,"given":"Medhavi","family":"Vashisth","sequence":"additional","affiliation":[{"name":"National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taruna","family":"Anand","sequence":"additional","affiliation":[{"name":"National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,2]]},"reference":[{"key":"ref_1","unstructured":"WHO (2013). 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