Inhibition effect of graphene quantum dots against Alternaria alternate and Botrytis cinerea and their potential application in strawberry preservation

• GQDs showed strong inhibitory potential against Alternaria alternate and Botrytis cinerea . • GQDs induced membrane damage leading to fungal inactivation. • GQDs@SA coated strawberries retained good qualities during storage. • GQDs@SA coating significantly inhibits the growth of spoilage microorganisms. Graphene quantum dots (GQDs), a novel carbon-based nanomaterial with remarkable broad-spectrum antibacterial properties, offer an alternative strategy for the preservation of fruits and vegetables. In this study, GQDs with good dispersibility and efficient antifungal properties were prepared by chemical oxidation, and the inhibition rate of GQDs (2 mg/mL) against spoilage bacteria commonly found in fruits and vegetables fungal pathogens Alternaria alternate ( A. alternate ) and Botrytis cinerea ( B. cinerea ) were 80.23% and 82.61%, respectively. Membrane damage is the primary mechanism of fungal death. High-throughput sequencing results indicated that the relative abundance of strawberry surface spoilage genera, including Pseudomonas, Achromobacter, Botrytis and Alternaria , was lower in the GQDs@sodium alginate (SA) coated group than in the control group. GQDs@SA coating is possible as a potential alternative for strawberry preservation management, and this study provides a new perspective for postharvest disease control and management of strawberries.