Plant-extract-infused edible films as natural antimicrobial and antioxidant packaging for chicken meat

Abstract

This study reports the development of starch-based edible films enriched with bioactive extracts from Pongamia pinnata and Psidium guajava leaves, valorized as underutilized agro-waste resources. Ultrasound-assisted ethanolic extraction followed by partial purification yielded phenolic- and flavonoid-rich fractions, with Fourier Transform Infrared Spectroscopy (FTIR) confirming quercetin and karanjin as key constituents. The extracts exhibited high bioactivity, with a total phenolic content of 800 µg mL⁻¹ GAE and a flavonoid content of 1295 µg mL⁻¹ QE. Edible films incorporating 5% (v/v) extracts demonstrated improved mechanical and barrier properties; P. guajava films achieved the highest tensile stress (2.57 MPa), while P. pinnata films showed the lowest Water Vapor Transmission Rate (WVTR) (1251.7 g m⁻² 24 h). Antioxidant activity was confirmed via DPPH assay (IC₅₀ of 49.32 and 54.76 µg mL⁻¹ for P. guajava and P. pinnata, respectively), alongside strong antibacterial activity against Staphylococcus aureus and Bacillus subtilis. Application to chicken meat reduced moisture loss, preserved pH and color, and suppressed microbial growth during short-term storage. Importantly, both plants are traditionally used in food and medicine, and no toxicity concerns were evident at the concentrations tested, supporting their safe use in edible films. Beyond chicken, these films have potential application in other perishable foods such as fish, fruits, and vegetables. Overall, the study demonstrates a sustainable valorization approach for agro-waste leaves and contributes to the development of clean-label, biodegradable packaging aligned with circular economy goals.