Antibacterial effect of the squalene extracted from the liver of the Persian Gulf spot tail shark Carcharhinus sorrah (Müller & Henle, 1839)

Squalene is an unsaturated triterpene hydrocarbon and is a precursor of steroids and cholesterol with antioxidant properties. The aim of this study was to isolate the squalene from the liver of the Persian Gulf spot tail shark Carcharhinus sorrah and to investigate its antimicrobial activity. Extraction was first done by methanol 70% and then, the squalene was separated through column chromatography with silica gel. Identification of the extracted squalene was done by thin layer chromatography (TLC) and gas chromatography coupled with mass spectrometry (GC–MS). Antibacterial properties of the squalene were identified and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were investigated by tubular dilution. Identification of the extracted compounds by GC-MS confirmed the presence of the squalene in the shark liver. Antibacterial studies showed that the squalene inhibited the growth of Gram negative (Escherichia coli, Klebsiella pneumonia and Vibrio harveyi) and Gram positive (Micrococcus roseus and Staphylococcus aureus) bacteria. Therefore, this metabolite has the potential to be more investigated for developing new antimicrobial compounds.