Resumen: This study investigated the bioactivity of bovine and ovine proteose-peptone (PPT) fractions, specifically the proteose-peptone component 3 (PP3) and its enzymatic hydrolysate. The antioxidant capacity of the above fractions and their activity against Cronobacter sakazakii and rotavirus were evaluated. Results revealed strong interspecies differences on their bioactivity. Thus, antioxidant activity of bovine PPT decreased with the fractionation but increased for ovine PPT, the latter being more active in all cases. Moreover, the antibacterial activity of hydrolyzed bovine PP3 showed high concentration-dependence reaching a maximum of 6.82 logarithmic cycle reduction at 4 mg mL−1, for 24 h of incubation. Conversely, neither intact nor hydrolyzed ovine PP3 were able to reduce the bacterial growth. Finally, both bovine and ovine PP3 neutralized rotavirus in a dose-response way, the former being more effective. Interestingly, the antiviral activity of bovine PP3 increased after hydrolysis, whereas the ovine counterpart lost almost all of its antirotaviral capacity. Idioma: Inglés DOI: 10.1016/j.idairyj.2024.106058 Año: 2024 Publicado en: INTERNATIONAL DAIRY JOURNAL 159 (2024), 106058 [9 pp.] ISSN: 0958-6946 Financiación: info:eu-repo/grantAgreement/ES/DGA/A20-23R Financiación: info:eu-repo/grantAgreement/EC/H2020/801586/EU/International Doctoral Programme for Talent Attraction to the Campus of International Excellence of the Ebro Valley/IberusTalent Financiación: info:eu-repo/grantAgreement/ES/MINECO/AGL2017-82987-R Tipo y forma: Artículo (Versión definitiva) Área (Departamento): Área Tecnología de Alimentos (Dpto. Produc.Animal Cienc.Ali.)