Characterization and Screening of Antagonistic Activity of Endophytic Fungi Isolated from Muntingia calabura

Endophytic fungi reside within plant tissues and contribute to plant health by producing bioactive secondary metabolites. This study focuses on the isolation, characterization, and antagonistic activity of endophytic fungi from Muntingia calabura. Healthy leaf samples were collected from Bangalore, India, and processed under sterile conditions. The fungi were isolated using Potato Dextrose Agar (PDA) and characterized based on macroscopic, microscopic, and molecular techniques using ITS sequencing. Molecular analysis confirmed the isolates as Aspergillus niger and Fusarium thapsinum. Antibacterial activity was evaluated using the disk diffusion method against Staphylococcus aureus and Escherichia coli. The results showed significant inhibition zones, indicating strong antimicrobial activity. This study highlights the potential of endophytic fungi as sources of natural antimicrobial agents for biocontrol and pharmaceutical applications.