Antimicrobial Activities of Phragmanthera incana (schum.) Balle, a Mistletoe Species Harvested from Two Host Plants against Selected Pathogenic Microbes

摘要

Aims: Phragmanthera incana , African mistletoe popularly called “bird lime”, devil’s fuge, “all heal, Iscador”, “mystyldene”, “golden bough” etc a hemi-parasitic plant was screened for its antimicrobial properties due to its ethnomedicinal claims as a remedy for stomach disorder, diarrhoea, dysentery, wound and other infections. Methodology: The antimicrobial activities of aqueous and methanol extracts of P. incana obtained from cocoa ( Theobroma cacao ) and kolanut ( Cola nitida ) were tested In vitro against five Gram negative pathogenic bacteria; Escherichia coli, Aeromonas popoffi, Proteus mirabilis, Klebsiella pneumoniae, Tatumella ptyseos and five Gram positive bacteria; Bacillus cereus, B. firmus, Paenibacillus assamensis, P. apiarius, Corynebacterium accolens ; and seven pathogenic fungi; Candida albicans, Aspergillus niger, A. flavus, Sclerotium rolfsii, Dinemasporium species, Mycotypha microspora and Harposporium species using agar diffusion method and food poisoning techniques. The antimicrobial activity was assessed by the presence or absence of inhibition zones, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) values. Results: Phragmanthera incana kolanut methanol extract showed a higher zone of inhibition for both bacterial and fungal isolates used than P. incana cocoa methanol extract which could be due to the phytochemical constituents. Phytochemical investigation of the mistletoe from cocoa and kolanut indicated the presence of alkaloid, phenolics, flavonoids, tannins, and cardiac glycosides. Phragmanthera incana aqueous extract from both plants (cocoa and kolanut) showed no antimicrobial activities towards the organisms used except for the food poisoning techniques for antifungal assay. Conclusion: This study showed a moderate antimicrobial potential of the extracts of the mistletoe, P. incana. Phragmanthera incana growing on kolanut was found to be more effective than P. incana growing on cocoa.