Antimicrobial activities of six plants used in Traditional Arabic Palestinian Herbal Medicine

Ethanolic extracts of six plants: Arum palaestinum Bioss, Urtica pilulifera L., Thymbra capitata (L.) Cav., Origanum syriacum L., Teucrium creticum L., and Teucrium polium L., used in Traditional Arabic Palestinian Herbal Medicine were evaluated for their antibacterial, anti-candida, and antidermatophyte activities using well diffusion, micro-dilution and food poisoned techniques. The extracts were tested against: six bacterial strains including Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli and Klebsiella pneumoniae; five Candida albicans isolates, and two dermatophytes: Microsporum canis, and Trichophyton rubrum. The most active plants extracts were T. capitata and O. syriacum against the tested bacteria, while the remaining plant extracts did not express any activity or exhibited only very low activity against tested bacteria species and candida isolates. O. syriacum was also the most active plant against all Candida strains with inhibition zones that ranged from 22.5 to 29.5 mm. On the other hand, T. capitata extract showed the highest activity against the test dermatophytes (producing a complete inhibition at ≤ 45 µg/mL). Key words: Medicinal plants, antibacterial activity, antifungal activity, Arum palaestinum, Urtica pilulifera, Thymbra capitata, Origanum syriacum, Teucrium creticum, Tecrium polium.