Comparative metabolic profiling of essential oils from Spondias pinnata (Linn. F.)Kurz and characterization of their antibacterial activities

Abstract

Essential oils obtained from the leaf, flower and fruit of Spondias pinnata (Linn. F.)Kurz cultivated in Egypt were analyzed by GC/MS. Sesquiterpene hydrocarbons represented the predominant components in the essential oils of leaf and flower (57.7% and 61.2%, respectively), followed by oxygenated monoterpenes, (30.4% and 28.8%, respectively). Whereas, the essential oil of fruit was rich in long chain alkanes (51.1%), and fatty acid esters (25.7%). It was observed that β-caryophyllene was the most predominant compound (49.9% and 53.3%)of the essential oils of leaf and flower, respectively, while in case of the fruit, the most predominant component was nonacosane (25%). The essential oil of leaf showed a remarkable antimicrobial effect against the investigated microorganisms viz. methicillin‐resistant Staphylococcus aureus (MRSA)and Salmonella typhymurium comparable to gentamicin. The essential oil of leaf also produced the highest inhibitory effect among the tested oils against Helicobacter pylori (91% inhibition, MIC of 1.95 μg/mL)when compared to clarithromycin (100% inhibition, MIC of 0.98 μg/mL). Furthermore, the essential oil of leaf exhibited a pronounced effect against Mycobacterium tuberculosis (84% inhibition, MIC of 0.49 μg/mL)when compared to the essential oils of fruit and flower. From these findings, it may be concluded that the essential oil of S. pinnata is a promising antimicrobial agent.