title: Extraction Method Plays Critical Role in Antibacterial Activity of Propolis-Loaded Hydrogels.
abstract: Extracted propolis has been used for a long time as a remedy. However, if the release rate of propolis is not controlled, the efficacy is reduced. To overcome this issue, extracted propolis was added to a cryogel system. Propolis collected from southern Brazil was extracted using different methods and loaded at different concentrations into polyvinyl alcohol (PVA) and polyacrylic acid hydrogels as carrier systems. The material properties were investigated with a focus on the propolis release profiles and the cryogel antibacterial properties against 4 different bacteria, namely: Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Pseudomonas putida. Swelling studies indicated that the swelling of the hydrogel was inversely related to propolis content. In addition, propolis release studies indicated a decreased release rate with increased propolis loading. PVA and PVA/polyacrylic acid-loaded propolis were effective against all 4 bacteria studied. These results indicate that the efficacy of propolis can be enhanced by incorporation into hydrogel carrier systems and that hydrogels with higher concentrations of propolis can be considered for use as bactericide dressing.
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland.
authors.forename: Gabriel G
authors.initials: GG
authors.lastname: de Lima
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland.
authors.forename: Ronaldo O
authors.initials: RO
authors.lastname: de Souza
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland.
authors.forename: Aline D
authors.initials: AD
authors.lastname: Bozzi
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland.
authors.forename: Malgorzata A
authors.initials: MA
authors.lastname: Poplawska
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland; Rehabilitation Medicine Centre, Mayo Clinic, Rochester, Minnesota 55902.
authors.forename: Declan M
authors.initials: DM
authors.lastname: Devine
authors.affiliation: Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland. Electronic address: mnugent@ait.ie.
authors.forename: Michael J D
authors.initials: MJ
authors.lastname: Nugent
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D004337:Drug Carriers / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry* / Q000494:pharmacology*; D011142:Polyvinyl Alcohol / Q000737:chemistry; D011429:Propolis / Q000737:chemistry* / Q000494:pharmacology*
chemical_list: D000180:Acrylic Resins; D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D020100:Hydrogels; C006903:carbopol 940; D011142:Polyvinyl Alcohol; D011429:Propolis
keywords: antioxidants; drug delivery systems; hydrogels; polymer synthesis; polymeric biomaterials