Problem

Post-harvest fungal spoilage remains one of the most costly challenges in global food supply chains, with up to 40–50% losses in onions and strawberries reported in major producing regions. Conventional chemical fungicides face increasing regulatory pressure, safety concerns, and resistance issues. Existing biological solutions, while safer, often suffer from enzyme instability and reduced catalytic activity under real-world temperature and pH conditions. The disclosed technology addresses these limitations through engineered chitinase variants with superior catalytic efficiency and nano-immobilization, offering a novel food-safe biocoating capable of protecting high-value produce such as strawberries, citrus, onions, and stored seeds.

Solution

This technology provides a novel antifungal preservation solution by combining an engineered, high-performance chitinase enzyme with a biodegradable polymer-nanoparticle delivery system. At its core is a truncated chitinase variant in which removal of a non-essential 21-amino-acid N-terminal segment increases solubility, reduces aggregation, improves expression efficiency, and delivers more than a two-fold boost in catalytic activity compared to the full-length enzyme. To further enhance stability and functionality, the engineered enzyme is covalently immobilized on MeO-PEG-PCL-Mal-PEG-PCL polymer nanoparticles using maleimide–thiol chemistry, producing a nanochitinase formulation with extended shelf life, superior thermal resilience, and consistent high-activity performance. This conjugation strategy also allows the enzyme to be oriented optimally for substrate access, outperforming both free chitinase and silica-based immobilization systems in enzymatic activity, biocompatibility, and storage stability. When applied as a fine mist spray, coating, film, or soaking solution, the nano-engineered chitinase effectively inhibits major food-spoiling fungi—including Aspergillus niger, Aspergillus fumigatus, and Penicillium digitatum—on produce such as strawberries, oranges, and onions for up to 25 days, demonstrating its strong potential as a safe, edible, biodegradable alternative to chemical fungicides across the food packaging, post-harvest preservation, and seed-treatment industries

Benefits

• High Antifungal Efficacy: 70–92% inhibition across major spoilage fungi; complete inhibition at higher concentrations.
• Extended Shelf Life: Protects produce for up to 25 days post-treatment.
• Enhanced Enzyme Stability: Covalent nano-immobilization increases activity, thermal stability, and storage longevity.
• Food-Safe Formulation: Biocompatible polymer nanoparticles reduce cytotoxicity concerns associated with silica-based systems.
• Versatile Application: Can be sprayed, wrapped, or coated depending on commodity and workflow.

Applications

• Fresh produce coatings for citrus, strawberries, onions, peppers, tomatoes
• Biodegradable food packaging films
• Seed treatments for crop protection
• Post-harvest storage and transport systems