Development of Eco-Friendly Packaging Films from Soyhull Lignocellulose: Towards Valorizing Agro-Industrial Byproducts

Green fabrication of biodegradable films: Harnessing the cellulosic residue of oat straw

Agricultural biomass is a sustainable source for developing biodegradable film to address mounting plastic perils. This study aims to investigate the influence of CaCl2 concentration on the properties of lignocellulose-based biodegradable film produced from oat straw biomass. Lignocellulose is extracted from oat biomass, and a green technique is employed to solubilize it in ZnCl2 solution and crosslinked with varying CaCl2 concentrations (200 mM-800 mM) to make films. The films containing 800 mM CaCl2 concentration demonstrated the lowest moisture content (12.81 ± 0.81 %), water solubility (43.91 ± 0.42), water vapor permeability (4.96 ± 0.14 × 10-11 gm-1s-1Pa-1), visible light transmittance (53.27 ± 0.69 %), and moisture absorption (42.42 ± 1.32 %). The tensile strength has increased remarkably from 4.24 ± 0.76 to 17.24 ± 3.68 MPa due to increased CaCl2 concentration from 200 mM to 800 mM. They degraded up to 83 % in soil with 20 % moisture after 28 days. Overall, films made of lignocellulose from oat straw biomass films demonstrate high strength and moisture barrier capabilities, rendering them suitable for use as food packaging materials.

Use of alfalfa cellulose for formulation of strong, biodegradable film to extend the shelf life of strawberries

Plastic packaging has increased concerns about human health and the ecosystem due to non-biodegradability. Several biopolymers, such as cellulose, starch, and proteins, are being explored, and cellulosic residue from agricultural biomass is suitable to overcome this predicament. Herein, cellulosic residue fibers (ACR) extracted from alfalfa were used to prepare biodegradable films by solubilizing them in ZnCl2 solution and crosslinking the chains with calcium ions (Ca2+) and sorbitol. Box Behnken Design optimized the ACR, CaCl2, and sorbitol amounts against the responses of water vapor permeability (WVP), tensile strength (TS), and elongation at break (EB). The optimized film combination was found to be 0.5 g ACR, 461.3 mM CaCl2, and 1.05 % sorbitol, making a 12 × 12 cm2 film, with a TS of 16.9 ± 0.4 MPa, EB of 10.1 ± 0.3 %, and WVP of 0.47 ± 0.11×10-10 g.m-1.s-1.Pa-1. It was translucent, blocked UVB light, followed Peleg's water absorption kinetics, displayed anti-oxidant activity, and biodegraded within 35 days at 24 % soil moisture. The ACR film extends the shelf life of strawberries by two more days compared to polystyrene film. The outcome offers a novel path to utilize and conserve natural resources and mitigate plastic perils, promoting a circular bioeconomy and sustainability and a win-win situation between the environment and farmers.