Phytochemical Screening, Acute Toxicity and Antibacterial Activity of Methanolic Stem Bark Extract of Hibiscus Rosa-Sinensis

Abstract

This study was conducted to determine the phytochemical constituents, acute   toxicity and antibacterial activity of methanolic stem bark extract of. Hibiscus rosa-sinensis. The stem bark was collected, air dried, grounded and extracted using maceration method with methanol. The methanol extract of the stem bark was used for phytochemical screening, acute toxicity studies and anti-bacterial activity. The phytochemical screening of this extract revealed the presence of alkaloids, flavonoids, saponins, steroids, tannins, terpenoids, cardiac glycosides, carbohydrates except anthraquinones which was not present. The acute toxicity studies of the extract indicated that: Hibiscus rosa-sinensis had LD_{50 value of} above 5000 mg/kg. The result of antibacterial activity showed that the stem bark extracts was found to have a significant effect (P<0.05) against the growth of Staphylococcus aureus and Escherichia coli. The Methanolic stem bark extract had MIC of 50.0 mg/ml and 200 mg/ml and MBC of 100 mg/ml and >200 mg/ml, against S. aureus and E. coli respectively. The result obtained is an indication that the stem bark of the plant can be used for treatment of bacterial ailment as claimed by traditional practitioners in Giambi Local Government Area of Kaduna State, Nigeria. Further research such as isolation of the active component should be carried out to validate the use of this plant in the traditional medicine as antibacterial agents.