A Study on the Antimicrobial Activity of Hibiscus Sabdariffa (roselle)extracts Against Staphylococcus Aureus and Escherichia Coli

ABSTRACT
Hibiscus sabdariffa, commonly known as (roselle), is a plant widely known for its medicinal and industrial properties. This study aims to investigate the antimicrobial activity of hibiscus sabdariffa (roselle) extracts against two pathogens, Staphylococcus aureus and Escherichia coli, carried out with two extracts, a methanolic extract and an aqueous extract. The study involved the extraction of phytochemicals from hibiscus sabdariffa with two solvents, methanol and water, which was carried out using the standard method. The antimicrobial activity of these extracts (ME and AE) was then evaluated by an agar well diffusion test using gentamicin as a positive control and sterile water as a negative control and also by minimum inhibitory concentration and minimum concentration bactericidal against Staphylococcus aureus and Escherichia. coli using the liquid dilution method. The results showed that hibiscus sabdariffa extracts showed significant antimicrobial activity against Staphylococcus aureus and Escherichia coli. The zones of inhibition observed in the agar diffusion assay for both pathogens for the methanol extract were between 12.5 mm and 24 mm while for the aqueous extract they were between 7 mm and 19 .7 mm and the MIC values for Staphylococcus aureus for ME. and AE were 50 mg/ml and the MBC values were both 25 mg/ml, while the MIC values for Escherichia coli were 12.5 mg/ml and 25
m/ml and the MBC values were 6.25 mg/ml and 50 mg/ml. The antimicrobial activity of hibiscus sabdariffa extracts can be attributed to the presence of phytochemicals such as flavonoids, tannins, alkaloids. These compounds have been reported to have antimicrobial properties against various microorganisms, including Staphylococcus aureus and Escherichia coli. The study highlights the potential of hibiscus sabdariffa extracts as a natural antimicrobial agent against Staphylococcus aureus and Escherichia coli.