In this study, the active polycaprolactone (PCL)/ polylactic acid (PLA) films containing different ratios of polymers (100:0, 80:20, 70:30) and concentrations of green tea extract (GTE) (10, 20, and 30% w/w) were fabricated. The GTE was extracted by the traditional maceration method and the results indicated that its phenolic content was 64.76 mg gallic acid/g extract and IC50 as antioxidant potential was 0.251 mg/ml. Also, the diameter of the inhibition area in well-diffusion test against E. coli and L. monocytogenes was measured 12 ± 0.78 and 14 ± 0.56 mm, respectively. The highest release of GTE components from active composite films was obtained in a lipophilic simulant solution containing 50% ethanol. The variation range of antioxidant activity of films in lipophilic and hydrophilic solutions was 14–64% and 2–6%, respectively. The increase of GTE concentration in films improved their antioxidant and antimicrobial properties. The highest bacterial growth inhibition was 0.45–1.07 Log CFU/ml which was observed in the presence of PCL/PLA films containing 30% (w/w) GTE against pathogenic bacteria (L. monocytogenes and E.coli). The application of PCL/PLA- GTE (30% w/w) film as an active packaging could reduce microbial growth by 35.84% and lipid oxidation by 40% on sausage samples in comparison with the unwrapped control sample. The observations could offer novel PCL/PLA films containing natural active components with antibacterial and antioxidant properties for use as a green biodegradable wrapping and alternative to traditional packaging in the food industry to prolong the food shelf-life.

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