GC-MS Identification of Secondary Metabolites from Static Cultures of Endophytic Fungi Isolated from Psidium guajava Roots: A Potential Source of Bioactive Compounds

Abstract The rising demand for innovative therapeutics has prompted a renewed interest in natural products derived from endophytic fungi. These microorganisms have shown significant potential as reservoirs of structurally diverse and biologically active secondary metabolites, providing a cost-effective and time-efficient alternative route. In this study, endophytic fungi were isolated from the roots of Psidium guajava using a nutrient-rich malt-glucose liquid culture medium comprising 3% malt extract and 6% glucose. The resulting fungal extract was subjected to GC-MS analysis using a system equipped with a TG-5MS capillary column (30 m × 0.25 mm × 0.25 µm) coated with 5% Phenyl methyl polysiloxane for efficient separation of volatile constituents. The analysis identified fifteen major compounds present in the extract. These results demonstrate that endophytic fungi isolated from Psidium guajava roots are a promising source of structurally diverse and potentially bioactive secondary metabolites. The application of GC-MS facilitated the effective detection and identification of key compounds, laying the groundwork for further pharmacological evaluation and potential therapeutic development.