Morphological and chemical characterizations of jujube (Ziziphus jujuba Mill.) to select superior accessions

Abstract

The fruits of jujube (Ziziphus jujuba Mill.) are consumed worldwide as food and herbal medicine because of their impact on human health and benefits. Here, phenotypic and chemical variation of this species was investigated to select superior accessions. The selected accessions showed significant differences based on the measured characteristics. Fresh fruit weight varied from 2.72 to 6.42 g with an average of 4.54, while dry fruit weight ranged from 0.89 to 2.57 g with an average of 1.55. Total phenolic content ranged from 1.69 to 14.05 mg gallic acid equivalent (GAE) g−1 fresh weight (FW) and total flavonoid content varied from 0.25 to 2.01 mg quercetin equivalents (QE) g−1 FW. Total anthocyanin content varied from 5.98 to 76.32 µg CyE g−1 FW. Radical scavenging activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate [DPPH]) ranged from 1.32 to 5.82 mg ascorbic acid equivalents (AsAE) g−1 FW, while ferric reducing antioxidant power (FRAP) varied from 35.37 to 93.35 µM FeSO4. The present study showed high diversity in morphological and chemical properties of jujube accessions. Based on the traits related to fruit quality such as fruit weight, fruit skin color, and fruit flavor, as well as in terms of chemical characteristics related to medicinal properties such as total anthocyanin content and antioxidant activity, 13 accessions were superior and are recommended to use in breeding programs. The commercial orchard of those best accessions should be extensively constructed to take advantage of the high yield of this tree as a crop and its medicinal properties.