Antibacterial activity of Magnolia alba flower extracts on Staphylococcus epidermidis and Staphylococcus aureus

Abstract The white champaca (Magnolia alba) plant has been reported possess antioxidant and antimicrobial activity. The aim of this study was to investigate the antibacterial activities of n-hexane, ethyl acetate, and methanolic Magnolia alba flower extracts on Staphylococcus epidermidis and Staphylococcus aureus. In this study, we also determined the secondary metabolites of the extracts by the phytochemical screening assay. The antibacterial activity of the Magnolia alba flower extracts was determined by the Kirby-Bauer diffusion method. The phytochemical screening assay showed that n-hexane extract contained of flavonoids, terpenoids, and steroid, while the ethyl acetate and methanolic extracts contains of alkaloids, flavonoids, terpenoids, and steroid. The antibacterial activity of the n-hexane, ethyl acetate, and methanolic Magnolia alba flower extracts was determined at four different concentrations of 5, 10, 20, and 50%. Results indicated that n-hexane extract had no activity against Staphylococcus epidermidis and Staphylococcus aureus. Meanwhile, ethyl acetate and methanolic extracts had antibacterial activities against Staphylococcus epidermidis and Staphylococcus aureus. The diameter zones of inhibition exhibited by the ethyl acetate extract against Staphylococcus epidermidis and Staphylococcus aureus ranged between 10.45 - 21.03 mm and 10.26 - 26.13 mm respectively. Meanwhile, the diameter zones of inhibition exhibited by the methanolic extract against Staphylococcus epidermidis ranged between 11.96 - 18.01 mm and against Staphylococcus aureus ranged between 7.23 - 13.9 mm. In conclusion, the ethyl acetate Magnolia alba flower extracts gave higher antibacterial activity against Staphylococcus epidermidis and Staphylococcus aureus.