Octacosanol preserves postharvest apple quality by delaying senescence through coordinated regulation of cuticular wax biosynthesis and antioxidant defense mechanisms

Abstract Apples, as respiratory climacteric fruit, undergo postharvest ripening and senescence, impacting commodity value. Cuticular wax protects against environmental stresses. Here, gas chromatography-mass spectrometry (GC-MS) analysis revealed a decline in fatty alcohol levels in apple wax during storage, correlating with fruit quality deterioration. Notably, octacosanol content significantly decreased with storage, suggesting that it is a primary cause of wax and fruit quality decline. Octacosanol treatment improved fruit quality and delayed softening by enhancing wax synthesis and antioxidant levels and suppressing cell wall-degrading enzymes. Transcriptome sequencing and real-time quantitative polymerase chain reaction (RT-qPCR) assays indicated increased expression of wax, peroxidase, sucrose, and starch genes and decreased expression of cell wall degradation genes, explaining octacosanol’s benefits. This study provides a theoretical basis for octacosanol application in fruit preservation.