Abstract:
Background: The use of herbal plants in the development of antimicrobial dosage forms plays a
major role. Mangifera zeylanica is an endemic plant which is commonly known as “Etamba” in
Sri Lanka. The stem bark of this plant has shown antimicrobial activity in previous research
studies.
Objective: To evaluate the antimicrobial activity of M. zeylanica leaves against selected
microorganisms
Methods: Leaves of the plant M. zeylanica were collected from Gampaha District Sri Lanka, and
authenticated by the National Herbarium, Sri Lanka. The leaves were sequentially reflux extracted
with ethyl acetate and ethanol and investigated the antimicrobial activity against Staphylococcus
aureus (ATCC 25923), Escherichia coli (ATCC 25932), Candida albicans (ATCC 10231),
Pseudomonas aeruginosa (ATCC 27953), and Staphylococcus epidermidis (ATCC 12228) using
agar well diffusion assay. Ampicillin (0.01 mg/mL), Gentamycin (0.01 mg/mL), Nystatin (0.1
mg/mL), Gentamycin (0.01 mg/mL) and Clindamycin (0.002 mg/mL) were used as the positive
controls respectively, while sterile distilled water was used as the negative control. Minimum
Inhibitory Concentration (MIC) and Minimum Bacterial Concentration (MBC) were tested against
concentrations from 200 mg/mL – 0.0245 mg/mL of ethanolic leaf extract.
Results: The highest antimicrobial activity was shown at 200 mg/mL of both extracts against
S. aureus, E. coli, C. albicans, P. aeruginosa, and S. epidermidis, with the mean(±SD) inhibition
zones as follows: by ethanol extract, 24.00(±0.00) mm, 19.80(±0.40) mm, 26.90(±0.40) mm,
24.80 (±1.30) mm, and 22.00 (±0.30) mm, respectively; and by ethyl acetate leaf extract, 23.40
(±0.20) mm, 18.70(±0.30) mm, 25.90(±0.50) mm, 24.40(±0.50) mm, 18.20(±0.30) mm,
respectively. Ethanolic leaf extract had MIC and MBC values of 25 mg/mL.
Conclusions: The study concludes that the ethanolic leaf extract of M. zeylanica possesses the
highest antimicrobial activity in comparison to ethyl acetate leaf extract, and with further
investigation, it can be used as a potential therapeutic agent for microbial infections.
