Exploring endophytic fungi from Cynodon dactylon: GC-MS profiling and biological activity

The rapid decline of significant plant species due to deforestation and slow regrowth has endangered many trees that are crucial for producing life-saving medications. This dual crisis of conserving plant biodiversity while meeting pharmaceutical demands necessitates innovative solutions. Endophytic fungi, naturally occurring symbionts within plants, present an eco-friendly and economically viable alternative. These fungi can produce a wide range of bioactive compounds, offering a sustainable source of pharmaceuticals. This study investigated endophytic fungi isolated from the inflorescence, leaf, and culm of Cynodon dactylon, a perennial medicinal grass. The research involved the isolation of endophytic fungi on potato dextrose agar (PDA) and water agar (WA), extracting secondary metabolites, and performing antimicrobial and antioxidant assays and gas chromatography-mass spectroscopy (GC-MS) profiling. A total of 21 endophytic fungi were isolated, with species of Alternaria, Aspergillus, and Cladosporium being predominant. These fungi were identified through morphological and molecular (internal transcribed sequences-ITS) characterization. Based on factors such as fungal dominance and specificity, five fungi (Aspergillus chevalieri, Aspergillus stellatus, Hypoxylon sp., and Xylaria apiculate) were selected and they exhibited significant activity against plant pathogens (Sclerotium rolfsii and Aspergillus niger) and radical scavenging properties in DPPH assays. GC-MS analysis revealed over twenty bioactive compounds in each fungal extract. These findings underscore the potential of endophytic fungi as sustainable sources of novel pharmaceuticals and effective biocontrol agents, offering a promising approach to address the current ecological and medicinal challenges.