Antibacterial activity of plectranthus cyaneus (Otto E. Schulz,1908) leaf extract against salmonella typhi and staphylococcus aureus
Abstract
Wound infections are a significant health threat, and the improper use of antibiotics has led to the development of antibiotic-resistant microorganisms. Salmonella typhi post-operative infections are rare, but they highlight the need for alternative treatments. Staphylococcus aureus is another bacterium that can cause serious wound infections. Traditional medicine, which uses plant-based treatments like Plectranthus cyaneus, provides a viable alternative in areas with limited access to modern healthcare. This study investigated the effectiveness of Plectranthus cyaneus ethanolic and hot water leaf extracts against Staphylococcus aureus and Salmonella typhi. The plant leaves were collected from Sheema district and prepared for extraction of phytochemical compounds using ethanol and hot water. Agar well diffusion and broth microdilution methods were used to determine antibacterial susceptibility, MIC, and MBC. Flavonoids, saponins, terpenoids, tannins, and phenolic compounds were detected in both extracts, although phenols were absent in the aqueous extract. S. aureus was susceptible to both extracts, with mean diameters of 19 mm for the ethanolic extract and 22 mm for the aqueous extract. Salmonella typhi was resistant to both extracts. The MIC values of ciprofloxacin, the ethanolic extract, and the hot water extract were 8.255 mg/mL, 135 mg/mL, and 1000 mg/mL, respectively. The MBC concentrations were 13.741 mg/mL (aqueous extract) and 5.993 mg/mL (ethanolic extract), indicating that the drug has the ability to act bactericidal against S. aureus. The study findings suggest that there is a synergistic mechanism by which the bioactive compounds in Plectranthus cyaneus leaf extracts act to inhibit growth or completely kill microorganisms. The study suggests Plectranthus cyaneus as a potential remedy for the treatment of wounds, and the extracts can be prepared using either of the methods used.