Determining the Effect of Plant Extracts on the Development and Characterization of Biodegradable Composite Films from Corypha umbraculifera L. Stem Starch

Abstract

Films and coatings fabricated with renewable biopolymers and antimicrobial agents have attracted research interest owing to their contribution to food safety and biodegradability. The study aimed to determine the effect of natural plant extracts from the leaves of curry tree, neem, tulsi, and Mexican mint in developing and characterizing biodegradable composite films of talipot starch and carboxymethyl cellulose (CMC) matrices. Talipot starch isolated from the stem pith of talipot palm (Corypha umbraculifera L.) is an underutilized source of starch with a high yield (76%). All composite films were prepared using the solution blending-casting method. The dominant properties of biodegradable films such as structural, morphological, barrier, and antimicrobial properties were studied. The relative crystallinity (RC) of composite films comparatively decreased with native talipot starch film. The surface of the talipot starch film made with CMC and plant extracts showed higher roughness and opacity. Incorporation of plant extracts into talipot starch and CMC matrices decreased water vapor permeability (WVP) and oxygen permeability (OP), indicating the improved barrier properties of the films. Antimicrobial activity as assessed by the inhibition zone method showed that composite films exhibited excellent antimicrobial activity against Staphylococcus aureus and Escherichia coli. These results revealed that biodegradable composite films from the non-conventional starch of talipot palm can possibly be used as a substitute for the one- time use petroleum-based films and can be used as a bioactive packaging material for food applications.