Dual-functional Blumea balsamifera leaves-derived carbon nano preservative for fresh-cut apples preservation

This study investigated the development of carbon dots nano preservative derived from Blumea balsamifera ("Ai-Na-Xiang" in Chinese) leaves (B-CDs), exploring its potential for preservation of fresh-cut apples through a combination of antimicrobial and antioxidant properties. Its π-π stacked carbon core and rich surface functional groups on the surface provide the structural basis for stronger photodynamic bactericidal activity and antioxidant properties of the carbon dots. The B-CDs demonstrated a bacterial inhibition rate exceeding 3.74 log under light exposure and a 21-fold increase in DPPH radical scavenging activity compared to the leaf extract. The preservation potential of B-CDs was further evaluated through storage tests with fresh-cut apples. The B-CDs effectively reduced microbial contamination, minimized weight loss, and preserved vital nutrients such as vitamin C, total acidity, and total phenols, thereby extending the shelf life of the apples by up to 8 days. The study provides a theoretical and practical foundation for the development of natural nanomaterials derived from agricultural by-products, paving the way for the high-value utilization of B. balsamifera tree resources, and advancing food preservation technologies. • Dual oxidant-antioxidant effects can be observed in Blumea balsamifera leaves-derived carbon dots (B-CDs) because of its core-shell structure. • B-CDs showed antimicrobial and antioxidant properties, enhancing fresh-cut apples preservation without harmful chemicals. • B-CDs extended the shelf life of fresh-cut apples by up to 8 days, offering a safe, natural, and efficient solution for the preservation of fresh-cut fruits.