Antimicrobial and antiproliferative activities of some North African desert plants
The landscape of southern Tunisia areas is dominated by shrubs and woody plant species. Their morphological and physiological features being suitable for arid and Saharan bioclimate. It can be estimated that their phytochemical characteristics and metabolic activities are in accordance with the environment, and the plants have special spectrum of secondary metabolites, and offer a great medical and pharmaceutical potential.
The present study aims the investigation of the biological activities on some plant species from the Tunisian region of Sahara. The studied species were: Anthyllis henoniana (Coss.), Centropodia forskalii (Vahl.), Cornulaca monacantha (Delile), Ephedra alata var. alenda (Stapf.) Trabut, Euphorbia guyoniana (Boiss. & Reut.), Helianthemum confertum (Dunal), Henophyton deserti (Coss. & Durieu), Moltkiopsis ciliata (Forssk.) and Spartidium saharae (Coss. & Durieu).
The antibacterial activity was evaluated on 19 strains of microbes by disc-difussion method with determination of the values of inhibition zones (7 – 14,5 mm) and minimum inhibitory concentrations (MIC = 0,1 – 5 mg/mL). Amoxicilin+clavulanic acid and vancomycin were applied as positive controls in the experiments. In vitro antiproliferative effect of the extracts was evaluated against 4 human adherent cell lines (HeLa, A431, A2780 and MCF7) using the MTT assay and cisplatin as reference compound. The aqueous-ethanolic (1:1) extracts of six desert plants showed antimicrobial activity against Bacillus subtilis, Moraxella catarrhalis, Staphylococcus aureus or methicillin-resistant Staphylococcus aureus. Extracts of E. guyoniana and H. confertum showed antiproliferative activity on breast adenocarcinoma (MCF7), and ovarian carcinoma (A2780) cell lines.
Our screening study proved that Saharan plant species are promising sources of potential antibacterial and antitumor agents. Our findings serve as starting points for selection of plant species for further investigation.