Lychee peel extract-based magnetic iron oxide nanoparticles: Sustainable synthesis, multifaceted antioxidant system, and prowess in eco-friendly food preservation

Abstract

The quest for sustainable synthesis methods has led to the exploration of lychee peel extract (LCPEx) as an eco-friendly alternative in the field of nanomaterials. This groundbreaking study introduces the synthesis of lychee peel extract-based magnetic iron oxide nanoparticles (LCPEx-MIONPs) and delves into their diverse applications. The meticulous methodology involved a multistep process for lychee peel extraction, resulting in the creation of LCPEx. The subsequent synthesis of LCPEx-MIONPs, achieved by combining the extract with iron chloride as a precursor and sodium hydroxide as a pH adjustor (set to 7.5), yielded nanoparticles with nanoscale dimensions (8.7± 0.4 nm) and diverse morphologies (cubic, hexagonal, spherical). Comprehensive characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), unveiled the structural attributes of LCPEx-MIONPs. The LCPEx exhibited robust antioxidant activity against DPPH, reaching its maximum inhibitory within only 5 minutes in a simple disc diffusion. The multifaceted antioxidant system of LCPEx-MIONPs exhibited an IC50 value of 202.3 µg/mL, highlighting the synergistic effects of lychee phytochemicals and magnetic ions. Beyond antioxidant capabilities, LCPEx-MIONPs, when incorporated into banana-based food preservation films, demonstrated significant prowess in grape preservation. The controlled release properties led to a notable reduction in water loss (9.3% on day 3 and 19.7% on day 6) compared to control grapes without LCPEx-MIONPs incorporated (18.2% on day 3 and 34.8% on day 6). This study significantly contributes to green nanotechnology, food preservation, and the development of eco-friendly hydrogels and bioplastic films, emphasizing the versatile applications of LCPEx-MIONPs in antioxidants, sustainable food preservation, and hydrogel-based bioplastics.