Development of Plumeria alba extract supplemented biodegradable films containing chitosan and cellulose derived from bagasse and corn cob waste for antimicrobial food packaging

Abstract

With the increase in global plastic pollution due to conventional plastic packaging (petroleum-derived), bioplastics have emerged as an alternative green source for practising a circular economy. This research aimed to extract cellulose from bagasse and corn cob waste and utilized in mixed form to prepare bioplastic film. The mixed cellulose was further reinforced with natural substances such as chitosan, bentonite, and P. alba extract. These newly developed bioplastics films were characterized by various physical tests like film thickness, moisture content, water solubility and spectroscopic techniques such as Fourier transform infrared (FTIR), scanning electron microscopy-energy dispersive spectroscopic (SEM-EDX), thermal gravimetric analysis (TGA), and ultraviolet-visible (UV-Vis) spectroscopy for opacity testing. The results revealed the enhanced bioplastic thermal and mechanical characteristics through robust interactions between cellulose and bentonite molecules. Moreover, incorporating chitosan solution as reinforcements in bio-composite films resulted in improved water barrier properties. The results indicated lower absorption in the UV range of 250-400 nm, attributed to the absence of UV-absorbing groups. Finally, their biodegradability was tested in soil, and 85.3 % weight loss of bioplastic films was observed after 50 days of the experiment which is the main task of this research. The antimicrobial properties of bioplastic films have been evaluated, and showed an inhibition zone of 16 mm against E. coli. After 12 days of incubation of sherbet berries, complete spoilage is identified in the control group compared to those covered with the bioplastic film. This outcome is attributed to the antioxidant and antimicrobial activities provided by chitosan and P. alba extract in the bioplastic film. The comprehensive outcomes of this study suggest the potential future adoption of these entirely bio-derived, environmentally sustainable and biodegradable bioplastic films as a viable substitute for the plastic packaging currently present in the market.

Keywords: Agriculture waste; Berries; Natural substances; Sustainability; Wettability.