Application of Composite Preservative Based on Moringa Leaf Flavonoids and Chitosan in the Preservation of Fruits and Vegetables

This study developed a natural composite preservative (FCCP) based on Moringa leaf flavonoids and chitosan and evaluated its physicochemical interactions, antioxidant capacity, antimicrobial activity, and preservation efficacy on fresh-cut produce. Fourier-transform infrared spectroscopy (FTIR) confirmed the successful integration of flavonoids into the chitosan matrix via hydrogen bonding and other intermolecular interactions. Antioxidant assays (ABTS, DPPH, FRAP) demonstrated that FCCP, particularly at 1.5 mg/mL flavonoid concentration (FCCP-2), exhibited potent radical scavenging and reducing power, comparable to ascorbic acid. Antibacterial tests revealed significant inhibitory effects of FCCP-2 against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i>, indicating a synergistic enhancement from the composite system. In preservation trials on fresh-cut stem lettuce, lotus root, and blueberries, FCCP-2 effectively maintained firmness, reduced weight loss, delayed browning, and preserved color quality during 7-day refrigerated storage. Furthermore, FCCP-2 significantly lowered malondialdehyde (MDA) accumulation and sustained superoxide dismutase (SOD) activity, highlighting its role in mitigating oxidative stress. These results demonstrate the efficacy and broad-spectrum applicability of the Moringa flavonoid-chitosan composite as a safe, eco-friendly preservative for extending the shelf life and quality of fresh-cut fruits and vegetables.