Sustainable isolation and characterization of natural fibers from Musa acuminata stem for green composite development

This study reports the sustainable extraction and characterization of natural fibers from Musa acuminata stems, emphasizing their role as eco-friendly reinforcements for green composites in line with global sustainability goals. Over 100 million tonnes of banana biomass are generated annually worldwide, much of which is discarded, posing environmental challenges. Converting this residue into value-added fibers supports circular bioeconomy strategies and meets the growing demand for natural fiber composites. Fibers were isolated using an environmentally benign retting process and assessed for antibacterial, anti-biofilm, mechanical, thermal, and morphological properties. Antibacterial assays against Escherichia coli showed notable activity, with 100 μg extract producing a 21 mm inhibition zone comparable to streptomycin (23 mm), while 25 μg yielded 9 mm. Confocal Laser Scanning Microscopy confirmed biofilm disruption through strong propidium iodide staining. Mechanical testing revealed a tensile strength of 23.76 MPa at 0.32 strain, reflecting favorable ductility and strength. Thermogravimetric analysis indicated a primary degradation peak at 386.37 °C with 43.72 % mass loss, confirming thermal stability for polymer processing. Scanning Electron Microscopy showed fibrillated surfaces with microvoids and partial delamination, promoting interfacial adhesion in composites. These combined properties demonstrate Musa acuminata fiber as a renewable candidate for biomedical, packaging, and structural applications, advancing the global transition toward eco-friendly materials. • Antibacterial efficacy reaching 91.3 % of streptomycin's performance. • Over 80 % biofilm inhibition confirmed via confocal microscopy. • Thermal stability up to 386.37 °C, suitable for polymer processing. • Mechanical strength of 23.76 MPa with favorable ductility. • SEM evidence of surface roughness aiding fiber–matrix adhesion.