title: Algerian propolis extracts: Chemical composition, bactericidal activity and in vitro effects on gilthead seabream innate immune responses.
abstract: Propolis has been used as a medicinal agent for centuries. The chemical composition of four propolis samples collected from four locations of the Sétif region, Algeria, using gas chromatography-mass spectrometry was determined. More than 20 compounds and from 30 to 35 compounds were identified in the aqueous and ethanolic extracts, respectively. Furthermore, the antimicrobial activity of the propolis extracts against two marine pathogenic bacteria was evaluated. Finally, the in vitro effects of propolis on gilthead seabream (Sparus aurata L.) leucocyte activities were measured. The bactericidal activity of ethanolic extracts was very high against Shewanella putrefaciens, average against Photobacterium damselae and very low against Vibrio harveyi. The lowest bactericidal activity was always that found for the aqueous extracts. When the viability of gilthead seabream head-kidney leucocytes was measured after 30 min' incubation with the different extracts, both the ethanolic and aqueous extracts of one of the propolis samples (from Babor) and the aqueous extract of another (from Ain-Abbassa) provoked a significant decrease in cell viability when used at concentrations of 100 and 200 μg ml-1. Furthermore, significant inhibitory effects were recorded on leucocyte respiratory burst activity when isolated leucocytes where preincubated with the extracts. This effect was dose-dependent in all cases except when extracts from a third propolis sample (from Boutaleb) were used. Our findings suggest that some of Algerian propolis extracts have bactericidal activity against important bacterial pathogens in seabream and significantly modulate in vitro leucocyte activities, confirming their potential as a source of new natural biocides and/or immunomodulators in aquaculture practice.
authors.affiliation: Laboratory of Applied Biochemistry, Faculty of Natural and Life Sciences, University Ferhat Abbas Sétif 1, Algeria.
authors.forename: El-Khamsa
authors.initials: EK
authors.lastname: Soltani
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Cerezuela
authors.affiliation: Laboratory of Applied Biochemistry, Faculty of Natural and Life Sciences, University Ferhat Abbas Sétif 1, Algeria.
authors.forename: Noureddine
authors.initials: N
authors.lastname: Charef
authors.affiliation: Laboratory of Applied Microbiology, Faculty of Natural and Life Sciences, University Ferhat Abbas Sétif 1, Algeria.
authors.forename: Samia
authors.initials: S
authors.lastname: Mezaache-Aichour
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain. Electronic address: aesteban@um.es.
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Esteban
authors.affiliation: Laboratory of Applied Microbiology, Faculty of Natural and Life Sciences, University Ferhat Abbas Sétif 1, Algeria.
authors.forename: Mohamed Mihoub
authors.initials: MM
authors.lastname: Zerroug
mesh_terms: D000276:Adjuvants, Immunologic / Q000737:chemistry / Q000494:pharmacology*; D000462:Algeria; D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry / Q000662:veterinary; D007113:Immunity, Innate / Q000187:drug effects*; D007962:Leukocytes / Q000187:drug effects; D010776:Photobacterium / Q000187:drug effects*; D011429:Propolis / Q000737:chemistry / Q000494:pharmacology*; D021541:Sea Bream / Q000276:immunology*; D020614:Shewanella putrefaciens / Q000187:drug effects*; D014733:Vibrio / Q000187:drug effects*
chemical_list: D000276:Adjuvants, Immunologic; D011429:Propolis
keywords: Algerian propolis extracts; Bactericidal activity; GC–MS analysis; Gilthead seabream (Sparus aurata L.); Innate immunity; Teleosts