High added-value compounds with antibacterial properties from Ginja cherries by-products

Purpose To test the antimicrobial properties of the extracts of stems and leaves of Ginja cherry plant. Both stems and leaves are waste in the production of the cherry liquor and they could be valorised by extracting valuable compounds, making the process more environmentally sustainable. Methods The ethanol extracts from both stems and leaves were analysed by LC-ESI/MS to determine the phenolic composition. They were tested against Gram positive and Gram negative bacteria (Bacillus subtilis, Staphylococcus aureus MSSA, Staphylococcus aureus MRSA, Pseudomonas sp., Pseudomonas aeruginosa, Flavobacterium sp., Escherichia coli, Salmonella), using the disk diffusion technique and the broth dilution technique. Results The extracts showed good antibacterial properties towards Gram positive and Gram negative bacteria. The values of the Minimum Inhibitory Concentration (MIC) were lower for Gram positive bacteria (10-15 mg/ml) than for Gram negative ones (10-100 mg/ml). The values of Minimum Bactericidal Concentration (MBC) were between 2 and 4 times higher than the MICs. Conclusions The waste from Ginja cherry plants can be successfully employed to extract valuable compounds such as polyphenols, with antibacterial properties. © Springer Science+Business Media B.V. 2010.