Antimicrobial activity of extracellular compounds from endophytic fungus BAR1.5 cultivated with different media

Abstract

Endophytic fungi are microorganisms that live inside the plants that are known to be able to produce the same bioactive compounds as their host plants. Endophytic fungus BAR1.5 was isolated from Rhizophora stylosa leaves collected from the mangrove area of Barru, South Sulawesi. The extracellular components of fungal endophytes are known to have higher antimicrobial activity than the intracellular compounds. Furthermore, the growth of endophytic fungi is strongly influenced by nutrients in the culture media, so that it may affect the production of its secondary metabolites. The aim of this study was to compare the production of extracellular compounds and its antimicrobial activity of the fungus BAR 1.5 cultured with different media (Potato Dextrose Broth, PDB and Hagem medium). The results showed that the endophytic fungus cultured on PDB media grew faster, produced more yield of extracts and showed stronger antimicrobial activity. Its extracellular compounds inhibited the growth of the tested bacteria which were Escherichia coli, Pseudomonas aeruginosa, Candida maltosa, Bacillus subtilis and Staphylococcus aureus. The strongest antibacterial activity was against B. subtilis with the inhibition zone was 12.5±0.3 mm. The extracellular compounds of the endophytic fungus BAR 1.5 contained terpenoids, polyphenols, and flavonoids.