Antimicrobial Activity of Five Yemeni Medicinal Plants against Selected Human Pathogenic Bacteria and Fungi

Background: The emergence and spread of antibiotic resistance, as well as the evolution of new strains of disease causing agents, are of great concern to the global health community. Nowadays, reports have indicated that many of healthcare-associated, antimicrobial-resistant bacteria are not only multidrug resistant pathogens but also broadly drug-resistant and pandrug-resistant bacteria. Objective: This study is focused on exploring the antimicrobial properties of five different plants that are commonly being used as traditional medicines in Yemen against Gram positive, Gram negative bacteria and fungi. Methods: The antimicrobial potential of five different plant extracts was screened against selected human pathogenic bacteria and fungi. Methanolic extracts of Dodonaea viscose, Plantago lanceolata, Withania samnifera, Pulicaria crispa, and Rumex nervosus were subjected to a test of their antimicrobial properties by Modified Agar Diffusion and Minimum Inhibitory Concentration. Results: The results indicated that all the five plants extract showed antibacterial activity against a selected microorganism at a concentration of 60 mg/ml. The highest potential was observed in the extract of W. somnifera against S. taphyloccocus aureus, Pseudomonas aeruginosa, Proteus miarbilis and Candida albicans with zone of inhibition of 23 mm, 20.7 mm, 20 mm and 25.3 mm, respectively. R. nervosus also showed the highest MIC against test organisms. Only two medicinal plant Pulicaria crispa, and Rumex nervosus extracts showed non antifungal activity. Conclusion: The experiment confirmed the efficacy of some selected plant extracts as natural antimicrobial and can be potential sources for the synthesis of antibacterial drugs.