Antibacterial Activity and Chemical Composition of Crude Extract and Oil of Zygophyllum (Fagonia) luntii (Baker) 1894 (Family Zygophyllaceae)

Abstract

Traditionally wild plants including Zygophyllum spp., containing many bioactive constituents, are used as medicine. Zygophyllum luntii from Zygophyllaceae family is wildly grown in Oman and has been used for medical purposes. The present study investigated the antibacterial activity of the crude extracts (leaves, stem and roots) and oil (leaves) from Z. luntii. These extracts were tested against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa in well diffusion assays utilizing Muller Hinton Agar (MHA). The hydrocarbon contents and the fatty acid methyl ester (FAME) components of the extracts were also determined by GC-MS. Significant antibacterial activity was observed in the Z. luntii leaves extract and significant differences (F=14.06, df=2, P=0.002) were found among E. coli, P. aeruginosa and S. aureus. The highest inhibition was observed against P. aeruginosa (15.5 ± 2.64 mm) then E. coli (11.25 ± 1.50mm) and S. aureus (3.50±4.72 mm). The Z. luntii extracts showed about 50-60% effectiveness against E. coli and P. aeruginosa compared to Ciprofloxacin. A total of 20, 19 and 8 compounds were detected from leaves, stem and roots extracts, respectively. Heneicosane, Docosane and Tricosane were found in the highest concentration in leaves; HOP-22(29)-EN-3.BETA.-OL and β-Sitosterol in stems, and Docosane and Tricosane in roots of Z. luntii. Nine types of fatty acids methyl esters were detected in oil extracted from leaves and methyl esters of Palmitic acid, Linolenic acid and Oleic acid constitutes 90% of the oil. This is the first report on antibacterial activity and chemical composition of Z. luntii.