Antimicrobial screening of crude extracts from the indigenous Ganoderma lucidum mushrooms in Namibia

The indigenous Ganoderma mushroom belongs to the class Basidiomycetous. It has been used in different systems of traditional medication for the treatment of diseases of human beings and animals. It contains various triterpenes, polysaccharides, alkaloids and steroids known to have broad effects pharmacologically and anti-bacterial properties. The indigenous Ganoderma mushroom has been used by locals in Namibia traditionally as a source of medicine to fight skin and wound infections, and other ailments. There is a need to validate the traditional usage of Ganoderma mushroom extracts on Escherichia coli,Alcaligenes faecalis, Proteus vulgaris, Neisseria meningitidis, Bacillus cereus andStaphylococcus aureus. This is important for the Namibian local communities, where people do not have access to modern medicines and use traditional medicines. This study analyzed the anti-bacterial effects of crude organic and aqueous extracts of the mycochemical components of the indigenous Ganoderma mushroom. Using the agar disc diffusion method, the crude extracts of the Ganoderma mushroom exhibited various degrees of inhibition against the tested organisms. The widest inhibitory zones (19.0 mm) were obtained with the crude benzene extract of G. lucidum against E. coli and N. meningitidis. The lowest zone of inhibition (6.0 mm) was demonstrated with the aqueous extract against E. coli. The study has concluded that the crude extracts of the indigenous Namibian Ganoderma mushroom possess antibacterial properties to all Gram positive and negative strains tested.   Key words: Ganoderma lucidum, antibacterial properties, Escherichia coli, Alcaligenesfaecalis, Proteus vulgaris, Neisseria meningitidis, Bacillus cereus and Staphylococcusaureus.