Antibacterial Activity of Moringa oleifera Leaf and Ganoderma lucidum Ethanolic Extracts Against Selected Bacteria

Abstract

Antibiotic resistance (AR) refers to the bacteria's ability to survive and multiply despite the presence of antibiotics, diminishing their effectiveness in treating infections. This challenge highlights the need to explore plant and fungi-derived antimicrobials to reduce reliance on synthetic antibiotics and manage AR. Medicinal plants and fungi, rich in bactericidal secondary metabolites, are gaining attention as natural therapeutic agents. Moringa oleifera Lam and Ganoderma lucidum are known for their antibacterial, antioxidant, and anti-inflammatory properties. This study aims to determine the antibacterial activity of M. oleifera leaf and G. lucidum ethanolic extracts against Gram-positive and Gram-negative bacteria, which are Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. In extract preparation, the study has conducted the ethanolic extraction ofM. oleifera leaf andG. lucidum. The antibacterial activity of both extracts was determined using agar-well diffusion, minimum inhibitory concentrations (MICs), and minimum bactericidal concentrations (MBCs) assays, against the Gram-positive and Gram-negative bacteria. In agar-well diffusion assay, M.oleifera leaf extract shows antibacterial activity against Gram-positive bacteria, which areB. subtilis andS. aureus, with the formation of inhibition zones observed ranging from ±10.67 to ±12.00 mm and ±11.00 to ±17.67 mm, respectively. Meanwhile,G. lucidum extract shows no antibacterial activity against all the tested bacteria. The MIC value of M. oleifera leaf extract was observed at 125 mg/mL against B. subtilis and 250 mg/mL against S. aureus, E. coli, and P. aeruginosa. Meanwhile, G. lucidum extract shows a higher MIC value of 250 mg/mL againstB. subtilis and S. aureus and 500 mg/mL against E. coli and P. aeruginosa. Based on the MBC/MIC ratio, it shows that the M. oleifera leaf ethanolic extract exhibits a bactericidal effect, while, G. lucidum ethanolic extract exhibits a bacteriostatic effect against the tested bacteria. The results obtained in this study is beneficial in providing data regarding the efficacy of M. oleifera leaf and G. lucidum extract to exhibit antibacterial activity against Gram-positive and Gram-negative bacteria. The findings can promote further research on M. oleifera leaf and G. lucidum extracts as synthetic antibiotic replacements.