Effects of novel green carbon dots on postharvest quality of mango fruits

Abstract Postharvest mango fruit are prone to various biotic and abiotic stresses, resulting in a relatively shorter shelf life that leads to large postharvest losses (30–60%) during storage and transit. Considering health and environmental concerns, postharvest application of chemical fungicides is prohibited. In this study, carbon quantum dots (CODs) were synthesized from mango peel, and these CQDs were applied (0, 2.0, 2.5, and 3.0%) to fresh mango fruit. The treated fruits were kept at room temperature and sampled every 2 days for quality assessment. The qualitative traits of fruit exposed to CQDs, such as firmness, weight loss, color development, ascorbic acid content, antioxidant activity, and total phenolic content, exhibited notable alterations. In general, weight loss, carotenoid accumulation, and prevalence of disease increased during storage. However, CQD application improved fruit appeal, maintained quality, and reduced anthracnose incidence in mango fruit during storage. The mango fruit treated with 3.0% CQDs had the longest shelf life of 12-d, followed by those treated with 2.5 and 2%. The untreated fruit had the highest disease incidence and the shortest shelf life. The 3% CQD treatment had the greatest effect on quality retention, with delayed anthracnose occurrence throughout storage. Therefore, the application of CQDs (3.0%) could be promising for preserving the shelf life and nutritional quality of mango cv. Malda during ambient storage for up to 12 days.