Evaluation of synergistic/antagonistic antibacterial activities of fatty oils from apricot, date, grape, and black seeds

The increasing antimicrobial resistance requires continuous investigation of new antimicrobial agents preferably derived from natural sources. New powerful antibacterial agents can be produced by simply combining oils that are known for their antibacterial activities. In this study, apricot seed oil (ASO), date seed oil (DSO), grape seed oil (GSO), and black seed oil (BSO) alone and in binary mixtures were assessed. Fatty acid profiles of individual oils and oil mixtures showed linoleic acid, oleic acid, palmitic acid, stearic acid, and linolenic acid contents. Linoleic acid was the most abundant fatty acid in all samples except for ASO, where oleic acid was the dominant one. GSO showed the highest total phenolic content while ASO showed the lowest one. Antibacterial screening was performed against Escherichia coli , Klebsiella pneumoniae , Pseudomonas aeruginosa , Proteus mirabilis , and Staphylococcus aureus . Results showed antibacterial activity in all oils against tested strains except for ASO against S. aureus . Highest antibacterial activity recorded was for ASO against P. mirabilis . ASO-GSO mixture (AG) was the best mixture where it showed synergistic interactions against all strains except P. aeruginosa . In conclusion, seed oil mixtures are likely to show promising antibacterial activities against specific strains.