Antimicrobial Activity of Fifty-Four Plants Used in Folkloric Medicine in Palestine

Ethanolic and aqueous extracts of fifty four plant species used in folk medicine in Palestine for treatment of several infections and diseases were investigated for their antimicrobial activities against thirteen microbial isolates belonging to one yeast, Candida albicans; four gram negative bacteria, Escherichia coli, Klebsiella pneumonia, Proteus vulgaris and Pseudomonas aeroginosa, and one gram positive bacterium, Staphylococcus aureus, and two isolates of dermatophytes, Microsporum canis and M gypseum, and five isolates of plant pathogenic mycelial fungi, Fusarium tricinicturn, Pythiurn ultimum, P. aphanidermatum, P. middletonii, and Phytophthora citrophthora. Two susceptibility tests were used in this work, the disk diffusion method for measuring the antibacterial and anticandidal activity and the poisoned—food technique for measuring the antifungal activity. The results demonstrated that the plans studied differ significantly in their activity against test microorganisms. The most active plants against both gram positive and gram negative bacteria include Alcea setosa, Coridothymus capitatus and Saturqa thymbra. For C. albicans, the most active plants include Coridothymus capitatus, Scztureja thymbra, and Quercus calliprinos. For dermatophytes, the most active plants include the ethanolic extracts of Coridothymus capitatus, Micromeria nervosa, and Satureja thymbra, and the aqueous extracts of Anthemis tunictoria and Verbascum sinuatum. For phytopathogenic Pythium sp., the most active plants the ethanolic extracts of Mcromeria nervosa, Pinus halepensis and Satureja thymbra and the aqueous extracts of Rubia tenugfolia, Anthemis tunictoria and Coridothymus capitatus. For phytopathogenic Phytophthora citrophthora the most active plants include the ethanolic extracts of Pinus halepensis and Satureja thymbra. For phytopathogenic F usarium tricinictum, the most active plants include the ethanolic extracts of Salviafruticoso and Satureja ihymbra and the aqueous extracts of Anthemis tunictoria and Juglans regia. Ethanolic extracts were more active than aqueous extracts for antimicrobial activity. Test bacterial strains differed significantly in relation to their susceptibility to different plant extracts used. The most susceptible test strain was S. aureus (gram positive bacteria), whereas the least susceptible strain was K. pneumonia (grana negative bacteria). For rnycelial fungi, the most susceptible phytopathogenic fungi was P. aphanidermatum, whereas the most susceptible dermatophyte was M gypseum to both aqueous and ethanolic extracts.