Chemistry and Bioactivities of Six Tunisian Species.

The complex taxonomy of genus, the renewed interest in natural compounds able to combat microbial strains, the overuse of synthetic pesticides, the consequent request for alternative control methods were the reasons for this research. The essential oils (Eos) of , , , , and were analyzed by GC/MS and their potential phytotoxic activity was evaluated against the germination and radicle elongation of , and . The antibiofilm activity was assayed against both Gram-positive ( and ) and Gram-negative ( and bacteria. Monoterpenoids were the most representative constituents in all EOs and eucalyptol was the dominant component except in EO, in which -cymene was the most abundant. In phytotoxic assays, the EOs from and were the most active against germination and radical elongation of the tested seeds. Finally, the EOs proved their capacity to effectively inhibit the adhesion process of all five pathogen strains, with percentages often reaching and exceeding 90%. These EOs could have possible employments in the food, health and agricultural fields.