The Antibacterial effect of Moringa oleifera leaf stalk extract against bacteria isolated from patients with eye infection (conjunctivitis) attending Federal Teaching Hospital, Katsina Federal

Abstract

The study evaluated the antibacterial effects of Moringa oleifera leaf stalk extract against bacterial strains isolated from patients with eye infection (conjuctivitis) attending the Federal Teaching Hospital (FTH), Katsina. With the increasing prevalence of multidrug-resistant bacterial strains causing eye infections, there is a pressing need for alternative treatments. Moringa oleifera, known for its antimicrobial properties, was investigated as a potential natural remedy to address this issue and provide cost-effective, accessible treatments. Fresh Moringa oleifera leaf stalks were collected, processed, and extracted using ethanol and distilled water. Phytochemical analyses were performed to identify active compounds. Bacterial isolates were collected from four infected patients, enriched, cultured, and identified. Antibacterial activity was assessed using agar diffusion, Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) tests, with ciprofloxacin as a standard control. The antibacterial activity of Moringa oleifera leaf stalk extract was assessed against Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, and Proteus vulgaris using both aqueous and ethanolic extracts at varying concentrations (100 mg/ml, 75 mg/ml, 50 mg/ml, and 25 mg/ml). The ethanolic extract exhibited superior antibacterial activity compared to the aqueous extract. At 100 mg/ml, the zones of inhibition for the ethanolic extract were 40.5 ± 3.5 mm for E. coli, 40 ± 5 mm for K. pneumoniae, 37 ± 2 mm for P. aeruginosa, 35 ± 4 mm for E. faecalis, and 32 ± 3 mm for P. vulgaris. In comparison, the aqueous extract at the same concentration produced inhibition zones of 32 ± 3 mm, 35 ± 4 mm, 30 ± 2 mm, 28 ± 3 mm, and 25 ± 2 mm for E. coli, K. pneumoniae, P. aeruginosa, E. faecalis, and P. vulgaris, respectively. The inhibition zones decreased as the concentration reduced, with the lowest values recorded at 25 mg/ml. At this concentration, the ethanolic extract showed inhibition zones of 27.5 ± 2 mm for E. coli, 28 ± 2 mm for K. pneumoniae, 26 ± 3 mm for P. aeruginosa, 23 ± 2 mm for E. faecalis, and 22 ± 1 mm for P. vulgaris, while the aqueous extract exhibited zones of 20 ± 1.5 mm, 22 ± 2 mm, 20 ± 2 mm, 17 ± 1 mm, and 12.5 ± 0 mm for the same organisms, respectively. These findings confirm the efficacy of Moringa oleifera leaf stalk extract, particularly the ethanolic extract, as a potential antibacterial agent for treating bacterial conjunctivitis. Phytochemical screening revealed the presence of saponins, tannins, and terpenoids as key bioactive compounds. The detecting of these phytoconstituents and subsequent antibacterial effect observed, could justify the use of the plant part in the folklore medicine and suggests the potentials of the M. oleifera leaf stalk as candidate for drug development to treat conjunctivitis. Further research is recommended to isolate and characterize its active components and evaluate its clinical efficacy.