Antibacterial activity of sesquiterpenoids and 8-O-methylated flavonoids from hexane fraction of clove(<i>Syzgium aromaticun</i>)

Abstract

According to World Health Organization reports, there is a major health challenge now and in the future due to increase resistance of bacteria to well-known antibiotics. This study aimed at identifying some vital metabolites from Hexane fraction of clove ( Syzygium aromaticum) using Liquid Chromatography Mass Spectrometer (LCMS) and its antibacterial activity against some foodborne pathogens. Syzygium aromaticum buds were extracted with Hexane using maceration method. This was followed by LCMS analysis for s econdary metabolites and then antibacterial activity using Agar well diffusion against four foodborne pathogens (Enterobacter spp, Salmonella spp , Escherichia coli, and Staphylococcus aureus). The Minimum inhibitory concentrations (MICs) and Minimum Bactericidal (MBC) of the clove extracts were also determined by the micro dilution method. The LCMS profile revealed the presence of significant metabolites such as Nevadensin (8 O methylated flavonoids) and 9 Hydroxymegastigma 4, 6,7 trien 3 one (Sesquiterpe noids) among others belonging to the well-known class of bioactive compounds that shows antioxidant and anti-inflammatory potentials. Based on the results obtained, Enterobacter spp was found to be the most susceptible organism with an average zone of 12.5 0±1 .20 mm, followed by E. coli 10.50±1.20 mm. The MIC and MBC of the extract against the test organisms ranged from 62.5 to 2 50 µg/ml. Therefore, the antibacterial activities observed might be as a result of these metabolites, and could be recommended for used in drug management or as antibacterial agent.