Edible Films With Quercetin and Orange Essential Oil: Physicochemical Characterization and Antifungal Activity

Abstract

This study provides evidence of the fungistatic capacity of an active edible film containing quercetin and orange essential oil (OEO), demonstrating favorable mechanical properties and stability for postharvest applications. Phytopathogenic fungi are a major cause of postharvest losses and waste. Certain bioactive compounds, such as quercetin (a key component of the natural chemical defense system of plants) and OEO, are known for their fungicidal properties. OEO contains a high concentration of terpene molecules that share chemical similarities with quercetin, potentially enhancing its bioavailability and toxicity. Active edible films offer a promising means of delivering bioactive compounds to help reduce the spread of fungal infections in food. Therefore, this study sought to develop an active edible film incorporating quercetin and OEO to inhibit the spore germination and growth of Colletotrichum gloeosporioides. Three edible films were formulated: PQN1 (0.075 mg/mL quercetin, 20 mg/mL OEO), PQN2 (0.030 mg/mL quercetin, 5 mg/mL OEO), and a control (PC) without active compounds. PQN1 exhibited the highest fungistatic activity, inhibiting C. gloeosporioides growth by 32.3 ± 0.8%. PQN1 also showed greater stability than PC, as indicated by zeta potential values (−63.3 ± 6.2 mV vs. −5.224 ± 5.4 mV, respectively). The elongation percentage and water vapor permeability (WVP) increased in films containing the active compounds, while tensile strength, Young’s modulus, and solubility decreased in the presence of OEO. No significant difference in thickness was observed. Overall, the PQN1 edible film shows potential for preventing C. gloeosporioides contamination in fruits and vegetables.