Post-harvest loss of fruits and vegetables, and health risks and environmental impact of current plastic packaging warrant new biodegradable packaging. To this end, cellulosic residue from agricultural processing byproducts is suitable due to its renewability and sustainability. Herein, soyhulls cellulosic residue was extracted, solubilized in ZnCl2 2 solution, and crosslinked with calcium ions and glycerol to prepare biodegradable films. The film combination was optimized using Box Behnken Design and film properties were characterized. The optimized film is translucent and exhibits tensile strength, elongation at break, water vapor permeability, hydrophobicity, and IC50 of 6.3 f 0.6 MPa, 30.2 f 0.9%, 0.9 f 0.3 x 10-10 gm-1 s- 1 Pa- 1 , 72.6 degrees, degrees , and 0.11 f 0.1 g/mL, respectively. The water absorption kinetics follow the Peleg model and biodegrade within 25 days at 24% soil moisture. The film extends the shelf life of raspberries by 6 more days compared to polystyrene film. Overall, the value-added soyhull cellulosic films are advantageous in minimizing post-harvest loss and plastic-related issues, emphasizing the principles of the circular bioeconomy.
Globally, approximately 2.12 billion tons of waste are annually disposed of, with laboratories significantly contributing across diverse waste streams. Effective waste management strategies are crucial to mitigate environmental impact and promote sustainability within scientific communities. This study addresses the challenges by introducing a novel method that transforms laboratory media waste into a valuable biopolymer named Agastic. The process involves repurposing agar extracted from bulk laboratory waste, blending it with bio-based plasticizers to produce Agastic sheets exhibiting mechanical properties comparable to traditional bioplastics. Using response surface methodology (RSM) and central composite design (CCD), optimal concentrations of agar (1.5-2.5% w/v), glycerol (0.25-1% v/v), and ethanolamine (0.5-1.5% v/v) were determined. Predictions from Design Expert software indicated impressive tensile strength up to 14.31 MPa for AGA-1 and elongation at break up to 52% for AGA-2. Fourier Transform Infrared Spectroscopy (FTIR) analysis confirmed agarose structural features in AGA-1 and AGA-2. Thermogravimetric analysis (TGA) showed polysaccharide-related breakdown between 38 degrees C and 280 degrees C in AGA-1, peaking at 299.36 degrees C; AGA-2 exhibited diverse thermal decomposition up to 765 degrees C, suggesting their biodegradable potential in packaging applications. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) analysis confirmed nontoxic nature of Agastic and preserved morphological integrity in both samples. Soil degradation studies revealed AGA-1 and AGA-2 losing 71.31% and 70.88% of weight, respectively, over 15 days. This innovation provides a sustainable pathway to repurpose laboratory waste into eco-friendly bioplastics, particularly suitable for moisture-sensitive packaging such as nursery applications. These findings underscore Agastic films' promise as environmentally friendly alternatives to traditional plastics, supporting circular bioeconomy principles and significantly reducing ecological impacts associated with plastic waste.
Plastics thrown out as trash are an everlasting threat to our biosphere and ecosystem. A sustainable remedy within our reach is the use of agricultural biomass. Herein, the lignocellulosic residue of switchgrass biomass, extracted using alkaline and bleaching treatments and solubilized in ZnCl2 solution followed by crosslinking with calcium ions, is used to develop biodegradable films. The films have been characterized for color, transparency, thickness, moisture, water solubility, water absorption, water vapor permeability, tensile strength, elongation, and soil biodegradation. Mathematical modeling of the water absorption and biodegradation behavior have also been studied. The films are transparent, possess high tensile strength and low water vapor permeability, and biodegrade completely within 40 days at 30% soil moisture. The tensile strength and whiteness of films increase with CaCl2 concentration, but elongation, water absorption, water solubility, water vapor permeability, and biodegradation decrease. Overall, the strong and biodegradable switchgrass residue-based films open up a new window of opportunities to design and develop reusable, recyclable, and compostable films from underutilized, inexpensive, and abundant agricultural biomass contributing to the circular bioeconomy in a friendly and sus-tainable manner.