The isolated Aspergillus flavus NSRN22 was used for green synthesis of silver and selenium nanoparticles (AgNPs and SeNPs). New food packaging films produced by combining each type of NPs with chitosan (CS) or sodium alginate (SA) were characterized. Transmission electron microscopy revealed that the average particle size was lower in case of AgNPs (9 to 14.7 nm) than SeNPS (36.8 to 53.5 nm). FTIR revealed a stronger connection between CS and NPs compared to SA and NPs. Tensile strength of CS (0.55 MPa) or SA (2.42 MPa) increased to 3.82, 4.73, 5.96, and 3.87 MPa for nanocomposite films of CS/AgNPs, CS/SeNPs, SA/AgNPs, and SA/SeNPs, respectively. Contrarily, water vapor pressures of SA (2132.57 g/m