Assessment of synergistic antibacterial activity of combined ethanolic leaf extracts of Azadirachta indica and Persea americana against Staphylococcus aureus

Khwakaa Gali

School of Pharmacy, Kampala International University, Uganda

ABSTRACT

Staphylococcus aureus (S. aureus) is one of the most dangerous bacteria because of the fatal infections that result from its colonization and multiplication in susceptible host organisms like human beings. This has led to the misuse of antibiotics, causing resistance of S. aureus against commonly used antibiotics. This continued use and misuse of antibiotics has resulted in the emergence of multidrug-resistant microorganisms, which is becoming a huge problem in animal farms, clinical human healthcare settings, and the community. P. americana and A. indica have both been used by locals in the management of numerous conditions ranging from infectious to non-infectious diseases. The main aim of this research is to assess the synergistic antibacterial activity of extracts of P. americana and A. indica against S. aureus in comparison to individual plant extracts. The study was experimental, involving the extraction of the plant leaves by maceration of dry powder in 70% ethanol for 3 days. The extracts were tested for the presence of phytochemicals, and the antibacterial activity was demonstrated using the agar well diffusion method. Results from phytochemical screening showed the presence of phenols, tannins, saponins, flavonoids, and terpenes in both plant extracts. The yields from the extracts of P. americana and A. indica were 16.77% and 12.59%, respectively. The MIC of P. americana was 6.25 mg/ml, and for A. indica, it was 25 mg/ml against S. aureus ATCC 25953. All extracts showed significant activity in comparison to vancomycin. The combination of the extracts was found to have a significant effect due to synergism with an FIC of 0.438 at a ratio of 1:3 and an FIC of 0.143 at a ratio of 3:1 of P. americana to A. indica. The extracts at a ratio of 1:1 showed indifference with an FIC of 1.25.

Keywords: Synergistic antibacterial activity; Combined ethanolic leaf extracts; Azadirachta indica; Persea Americana; Staphylococcus aureus

CITE AS: Khwakaa Gali (2024). Assessment of synergistic antibacterial activity of combined ethanolic leaf extracts of Azadirachta indica and Pe1•sea americana against Staphylococcus aureus. RESEARCH INVENTION JOURNAL OF BIOLOGICAL AND APPLIED SCIENCES 3(1):131-137.