Identification of apple fruits rich in health-promoting dihydrochalcones by comparative assessment of cultivated and wild accessions

Apple (Malus sp.) is the most important dietary source of dihydrochalcones (DHCs) that serve as valuable antioxidants, antidiabetics, and sweeteners. Although the technologies of DHC extraction and metabolic engineering are being developed and perfected, natural dietary sources are still significant. Therefore, to identify apples with high levels of these health-promoting DHCs, we conducted a large-scale investigation of 140 accessions and examined their DHCs profiles, concentrations of total phenolics and total flavonoids, and antioxidant capacity in the fruit (peel and flesh). Our results indicated that DHCs are major phenolics and significantly contribute to antioxidant capacity. Furthermore, these DHCs could be further enriched by an independent pathway. The great diversity and wide range of DHCs found in these accessions provide abundant natural materials for further efforts toward the breeding and utilization of apple fruits rich in these phenolics.