Preparation and characterization of pineapple leaf cellulose nanocrystal reinforced gelatin bio-nanocomposite with antibacterial banana leaf extract for application in food packaging

摘要

PCNC (pineapple leaf cellulose nanocrystal) is a cellulose nanocrystal that is derived from a low-cost precursor, namely, pineapple leaves by alkali treatment followed by acid hydrolysis. The average crystal size of PCNC was found to be around 52 nm with crystallinity index of 85%. PCNC were infused into gelatin matrix at five different weight percentages (1 to 5%) along with banana leaf extract to obtain a bio-nanocomposite by the solution cast method. The mechanical property and film thickness increased with an increase in PCNC concentration, whereas the swelling property, water vapor permeability (WVP), and oil permeability (OP) decreased. The morphology and thermal property of the films were studied by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), respectively. Antibacterial studies were conducted by the Well diffusion method by using Gram positive and Gram negative bacteria. From the above results, PCNC (5%)-reinforced gelatin bio-nanocomposite was optimised by the addition of banana leaf extract (BL). Antibacterial studies revealed improved activity against Escherichia coli and Staphylococcus aureus.