Sesquiterpenes from Pistacia lentiscus L. as potential antibacterial, antifungal and allelopathic agents

The present study investigated the antibacterial, antifungal and allelopathic activities of Pistacia lentiscus essential oils (EOs) isolated at the vegetative, flowering and fructification stages. The chemical composition of EOs varied according to both the phenological stages and the used mix plant parts. The main chemical class was sesquiterpene hydrocarbons with the predominance of germacrene D, delta-cadinene and beta-caryophyllene. The antibacterial activity was evaluated against five collection strains. At the vegetative stage, P. lentiscus EO was the most effective against Listeria monocytogenes and Echerchia coli as compared to the other stages. P. lentiscus EO also exhibited significant antifungal activity against the phytopathogenic strain Botrytis cinerea. Microscopic observation showed that EO induced swelling and crumbling of B. cinerea conidia. Moreover, P. lentiscus EO at the vegetative stage possessed significant allelopathic activity by inhibiting low concentration the germination and radical elongation of Raphanus sativus and radical elongation of Lepidium sativum.