Incorporation of yellow onion peel extract into the funoran-based biodegradable films as an antioxidant packaging material

This study was conducted to develop a biodegradable antioxidant film using yellow onion peel extract (YOPE) and funoran extracted from Gloiopeltis furcata. The mechanical, optical and antioxidant properties of the funoran films containing various amounts of YOPE (0.3%, 0.5% and 1.0%) were examined. YOPE dose-dependently increased the flexibility as well as the DPPH and ABTS free radical scavenging activities of the funoran films. Additionally, the total phenolic and total flavonoid contents of the funoran films increased from 31.92 to 61.31 mg gallic acid equivalent g(-1) film and from 21.80 to 79.22 mg quercetin equivalent g(-1) film after the incorporation of YOPE, respectively. These results suggest that the funoran-based film incorporated with YOPE, which was prepared from underutilised red alga and discarded onion peel, can be used as an antioxidant biodegradable packaging material.