ANTIOXIDANT ACTIVITY OF ALGINATE POLYMER FILMS INCORPORATED WITH NANOEMULSION OF PIMENTA DIOICA ESSENTIAL OIL

Objective: This study aimed to develop alginate polymeric films incorporated with nanoemulsion of Pimenta dioica essential oil and evaluate their antioxidant activity against free radicals. Methods: The essential oil was extracted by hydrodistillation and characterized by GC-MS. Nanoemulsions were prepared by phase inversion method and incorporated into alginate films by casting. Antioxidant activity was assessed by the hydroxyl radical scavenging method using salicylic acid, with IC₅₀ values calculated for the biofilm and compared to positive controls (diclofenac sodium and aspirin). Results: GC-MS analysis revealed eugenol (78.96%), chavicol (8.78%), myrcene (3.52%), and limonene (2.16%) as the major constituents. The biofilm-nanoemulsion system exhibited moderate antioxidant activity, with an IC₅₀ value of 85.33 ± 7.66 mg/L. Although higher than the positive controls diclofenac sodium (IC₅₀ = 2.65 ± 3.97 mg/L) and aspirin (IC₅₀ = 11.00 ± 16.50 mg/L), the observed activity was attributed to the synergistic effects of the major bioactive compounds, particularly eugenol and chavicol, which act as efficient hydrogen donors and free radical scavengers. Conclusion: The alginate films incorporated with nanoemulsion of Pimenta dioica essential oil demonstrated moderate antioxidant activity, attributed to the synergistic effects of the major bioactive compounds combined with the controlled release provided by the alginate matrix. These findings indicate that the biofilm-nanoemulsion system represents a promising natural alternative for active food packaging applications to retard lipid oxidation and preserve food quality.