Dioecy impacts the chemical profile and antibacterial activity of essential oils from leaves of Pistacia lentiscus L.

Pistacia lentiscus, commonly known as the mastic tree, is a dioecious plant of the Anacardiaceae family, widely used in Mediterranean traditional medicine for treating gastrointestinal, skin, and respiratory disorders. Although the medicinal properties of P. lentiscus have been extensively studied, the role of dioecy in influencing its chemical composition and antibacterial activity remains underexplored. This study aimed to investigate the impact of dioecy on the chemical composition and antibacterial activity of essential oils extracted from the leaves of male and female P. lentiscus plants. Essential oils were obtained by hydro-distillation from the female and male plant leaves of P. lentiscus growing in northern of Tunisia, their various organoleptic characteristics were recorded in accordance with AFNOR standards and analyzed using gas chromatography coupled with mass spectrometry. Their antibacterial activity was assessed against ten bacterial strains. The analysis revealed a predominance of non-oxygenated monoterpenes in all samples, with essential oils from female plants displaying greater molecular diversity. Antibacterial tests showed that essential oils from female plants were more effective against Gram-negative bacteria, particularly Escherichia coli and Klebsiella pneumoniae, while those from male plants were more active against Staphylococcus aureus. These findings emphasize the influence of dioecy on the chemical composition and antibacterial properties of P. lentiscus essential oils, highlighting the potential for gender-specific selection of plants for targeted antibacterial applications.