Nanoarchitectonics of antibacterial bio-packaging film from grapefruit peel-derived low methoxy Pectin integrated with silver nanoparticles

Abstract

Biopackaging films, such as those made from Pectin, are increasingly recognized for their sustainability in fruit preservation. This study utilizes Pectin derived from grapefruit peels to create films using evaporation casting. The research investigates factors, including Pectin concentration, sorbitol, calcium ions, and acetic acid. Film morphological and structural characterizations were performed using field emission scanning electron microscopy (FE-SEM), Energy Dispersive X-ray Fluorescence (XRF) spectroscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). Mechanical properties such as tensile strength (TS) and elongation at break (EAB), as well as physical properties like water vapor transmission rates (WVTR), soil biodegradation, and antibacterial capacity, were evaluated for both Pectin and Pectin/AgNPs films. The results revealed that acetic acid at a concentration of 6.67 g/L converted high methoxyl Pectin to low methoxyl Pectin, which improved gel formation. The optimal film formulation consisted of 10 g/L Pectin, 0.054 g/L calcium ions, and 5 g/L sorbitol, which enhanced film mechanical strength and soil decomposition capacity. Pectin/AgNPs films showed effective antibacterial activity against both Escherichia coli and Bacillus subtilis. Additionally, weight retention and sensory tests demonstrated that Pectin/AgNPs films successfully preserved cherry tomatoes for 10 days. Overall, Pectin and Pectin/AgNPs films show significant promise for fruit preservation, emphasizing their sustainability and effectiveness.