Document Type: Research article
Department of Drug and Food Control, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
Department of Pharmacognosy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Department of Drug and Food Control, Faculty of Pharmacy, International Campus, Tehran University of Medical Sciences, Tehran, Iran.
Pharmaceutical Quality Assurance Research Center, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran.
Biosurfactants, the microbial originated surface active agents, can modify the physicochemical properties of surfaces and reduce the bacterial adhesion via changing bacterial adhesion interactions on surfaces. They were also able to block oxidative chain reactions and might show antioxidant properties. The goal of this study was to evaluate the antioxidant and antibiofilm activities of biosurfactants which were derived from two autochthonous biosurfactant-producing strains, Bacillus amyloliquefaciens NS6 (surfactin), andPseudomonas aeruginosaMN1 (rhamnolipids). Their antioxidant activities were determined by ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods. Ferric thiocyanate (FTC) assay was used for determination of their lipid peroxidation inhibition capacity. Their effect to reduce the adhesion of Streptococcus mutans on polystyrene surfaces and disruption of its pre-formed biofilms were also investigated. Our results indicated that surfactin showed higher antioxidant activity than rhamnolipids and showed relatively similar efficiency to BHA that suggests it as a good alternative for synthetic antioxidants. In other hand, rhamnolipid conditioned surfaces showed higher antiadhesive and antibiofilm activity in comparison with surfactin treated surfaces.