title: Isolation and characterization of bacteria with antibacterial properties from Nile tilapia (Oreochromis niloticus).
abstract: One hundred and twenty bacterial isolates were obtained from the intestinal mucus of Nile tilapia (Oreochromis niloticus) and screened for antagonistic activity and adherence abilities. Based on in vitro antagonism against two pathogens (Streptococcus iniae and Edwardsiella piscicida), five isolates were selected and identified by 16S rRNA gene sequence analysis. All antagonistic isolates were affiliated to the genus Bacillus, which showed inhibitory activity against S. iniae. Only the isolate B191 (closely related to Bacillus mojavensis) inhibited the growth of both pathogens. Moreover, isolate B191 adhered significantly better to fish intestinal mucus than other antagonistic isolates. According to our results, these bacterial isolates, particularly isolate B191, should be further studied to explore their probiotic effects under in vivo conditions.
authors.affiliation: Department of Aquaculture and Fish Diseases, Faculty of Fisheries, University of Cukurova, Adana 01330, Turkey.
authors.forename: Miray
authors.initials: M
authors.lastname: Etyemez
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Girona 17003, Spain. Electronic address: jlbalcazar@icra.cat.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Balcazar
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology*; D001407:Bacillus / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D023681:Cichlids / Q000382:microbiology*; D020594:Edwardsiella / Q000187:drug effects*; D019936:Probiotics / Q000494:pharmacology; D012336:RNA, Ribosomal, 16S; D000070058:Streptococcus iniae / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D012336:RNA, Ribosomal, 16S
keywords: Adhesion; Antimicrobial activity; Fish pathogens; Potential probiotics