Bioactivity of Syzygium aromaticum (L.) Merr. & L.M.Perry extracts as potential antimicrobial and anticancer agents

Cancer is the most common cause of death every year. Moreover, high incidence of bacterial resistance to the most frequently used antibiotics contributes a significant death and disability worldwide. Hence, formulation of novel antimicrobial and anticarcinogenic agents is required. In the current study, the antibacterial efficiency of clove extracts (acetonic, dichloromethane, ethanolic, and petroleum ether) against four pathogenic bacterial strains [Escherichia coli, Salmonella typhi, Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA)] was estimated by disc diffusion method. Furthermore, the anticancer potency of S. aromaticum extracts against HCT human colon carcinoma was appraised using MTT assay. The phytochemical ingredients of the most effective extract were determined using gas chromatography–mass spectrometry (GC–MS) analysis. The dichloromethane extract presented the highest antibacterial potency against the pathogenic isolates recording minimum inhibitory concentration (MIC) of 1 mg/disc against MRSA strain and 0.5 mg/disc against both of E. coli and S. typhi strains. Furthermore, the minimum bactericidal concentration (MBC) of clove dichloromethane extract was recoded at 2 mg/disc against MRSA stain, and 1 mg/disc against E. coli and S. typhi strains. The dichloromethane extract of clove showed the lowest cytotoxic activity against HCT cell line whereas, the ethanolic extract exerted the highest efficacy with relative IC50 of 6.71 and 2.53 µg/ml respectively. GC–MS analysis revealed that the clove dichloromethane extract was comprised of eugenol (50.65%) and eugenyl acetate (12.54%) as major active components. In conclusion, clove extracts could be utilized as potential antibacterial and anticarcinogenic agents.