Phytochemical Screening and Antibacterial Properties of Croton hirtus L’Her. Plant Against Some Important Pathogenic Bacteria

摘要

The present study is aimed at evaluating the in vitro antimicrobial activity of different solvent extracts ofCroton hirtus L’Her. against ten medically important bacterial strains namely Escherichia coli, Enterococcussp., Salmonella typhi, Salmonella paratyphi, Bacillus thuringiensis , Bacillus subtili, Staphylococcus aureus,Pseudomonas fluorescens, Proteus sp. and Klebsiella pneumoniae. Phytochemical analysis and antimicrobialproperties of shoot, root and whole plant extracts of C. hirtus were investigated separately in methanol,ethanol, chloroform, acetone and water. Phytochemical screening reveals the presence of alkaloids, tannins,flavonoids, steroids, phenols, glycosides, terpenoids, anthroquinone, saponins and cardiac glycosides. Themethanol extract exhibited higher and wider range of activity against majority of the test organisms. Theshoot methanol extracts recorded highest activity against Bacillus thuringiensis (13.67 mm ZOI and MIC of600μg/mL), Bacillus subtili (13.83 mm ZOI and MIC of 600μg/mL) and Salmonella paratyphi (12.5 mm ZOIand MIC of 800μg/mL). The methanol whole plant extracts demonstrated highest activity against Salmonellatyphi (13.33 mm ZOI and MIC of 700μg/mL) whereas methanol root extracts demonstrated highest againstKlebsiella pneumoniae (13.33 mm ZOI and MIC of 800μg/mL) and Enterococcus sp. (10.5 mm ZOI andMIC of 1000μg/mL). The performance of methanol extracts was followed by chloroform extracts. Thechloroform whole plant extracts showed the highest activity against Escherichia coli (14.67 mm ZOI andMIC of 400μg/mL) and Staphylococcus aureus (12.67 mm ZOI and MIC of 800 μg/mL), whereas chloroformshoots extracts against Pseudomonas fluorescens (12.33 mm ZOI and MIC of 900μg/mL). The highestactivity against Proteus sp. was recorded in shoot acetone extracts (10.67 mm ZOI and MIC of 1000μg/mL).Water and ethanol extracts demonstrated the least activity against the test bacteria.