Antibacterial evaluation of South African Aloe ferox (Mill)

Abstract

Background: There has been an alarming increase in infections because of multidrug resistance. Several multidrug-resistant microbes are becoming more resistant to medications with several side effects. There is an urgent requirement for natural, safer and inexpensive antimicrobial agents.

Aim: The study sought to examine the effects of the antimicrobial activity of Aloe ferox (A. ferox) in different regions across South Africa.

Method: The antimicrobial activity was determined using the agar disk diffusion method. The minimum inhibitory concentration was determined using the microplate dilution method. 100 mg of dry extract was dissolved in 1 mL of ethanol, ethyl acetate and aqueous to obtain the concentration of 100 mg/mL dilutions (1:10, 1:100 and 1:500), respectively.

Results: The aqueous extracts showed antibacterial activity against all Gram-positive bacteria. Ethanol extracts showed greater inhibition of Gram-positive bacteria than ethyl acetate extracts. Ethanol showed inhibition on Gram-negative bacteria, that is, Protea vulgaris, Escherichia coli and S. sonnei. Aqueous and ethanol extracts displayed strong inhibition at the concentration of 1:10 against all fungal species across regions.

Conclusion: A. ferox showed inhibition to varying degrees across all the regions. The concentrations of A. ferox active ingredient used in traditional medicine differ by region. The study validates the potential difference in the antimicrobial activity of A. ferox across different geographical regions.

Contribution: This study adds to existing knowledge about the remarkable antimicrobial activity of A. ferox as a traditional medicinal plant because of differences in regions.