Antimicrobial activity of two natural plants grown in Egyptian environment: Ipomoea carnea and Tamarix nilotica

Abstract

: Plants are the largest biochemical and pharmaceutical stores ever known on our planet. Some medicinal plants have not found wider application and sometimes are referred as "forgotten plants". Antimicrobial activity of Ipomoeacarnea and Tamarixnilotica were evaluated by disk diffusion method and broth microdilution method. Extraction was performed by ethanol 50%. Results showed antibacterial activity of Tamarixniloticaextract with inhibition zones; 15, 14 and 19 mm against Bacilluscereus, Listeriamonocytogenesand Staphylococcusaureus, respectively. Ipomoeacarneaextract revealed a good effect against Staph.aureuswith 18 mm inhibition zone and MIC value against Staph.aureus was 8 mg/ml. Gram positive bacteria; B.cereus and L. monocytogenesshowed MIC value at 16 mg/ml likewise E.coliwas at 16 mg/ml. Pseudomonas aeruginosa and Salmonellatyphimurium were inhibited at 64 and 32 mg/ml, respectively. Gram positive strains were also susceptible to Tamarixnilotica extract with MIC values from 8 to 32 mg/ml. Gram negative strains were more resistant as MIC value were at 64 and 128 mg/ml. Bactericidal activity (MLC) at 16 mg/ml for both extracts against Staph. aureus while P. aeruginosa showed MIC at 128 mg/ml with Tamarixnilotica extract. Fungal strains were more resistant to the tested plant extracts whereas Ipomoeacarneaextract showed MIC value 16 mg/ml against Penicilliumitalicumwhile Aspergillusflavusand Rhizopusstoloniferanot inhibited at the highest concentration 128 mg/ml the yeast strains: Saccharomycescerevisiaeand Candidaalbicans were inhibited at 64 mg/ml. Tamarixniloticaextract showed MIC values ranged from 64 to 128 mg/ml against all tested fungal strains. It is reasonable to assessing their applicability and benefits using modern scientific analysis methods.