Maturity stages modulate fruit quality, bioactive constituents, and antioxidant activity of Prunus jenkinsii

Abstract

Researchers and consumers are highly interested in wild edible fruits around the world. Prunus jenkinsii grows in the wild and produces edible fruits, substantially contributing to the health, food, and livelihood of the people living in the eastern Himalayas, India. Although this species is extremely valuable, research on it is negligible. In this study, we investigated the changes in biochemical and functional properties at four different stages of fruit growth, including the immature, mature, ripe, and over-ripe stages, and determined the best stages for harvesting. Our findings showed that the fruit at the ripe stage had the highest fruit weight (6.57 ± 0.04 g), pulp content (43.33 ± 1.34%), total soluble solids (15.04 ± 1.14 °Brix), carbohydrate content (34.74 ± 0.08 mg glucose/g fw), phenols (552.41 ± 11.63 mg GAE/100 g fw), flavonoids (153.81 ± 3.44 mg QE/100 g fw), anthocyanins (313.03 ± 11.79 mg cyd-3-glu eq./100 g fw), and FRAP value (1374.54 ± 92.47 mM FeSO4 eq./100 g fw). These characteristics and their corresponding values increased from the immature stage to the ripe stage; then, they decreased in the over-ripe stage. The number of fruits, firmness, acidity, and ascorbic acid content decreased after ripening. The a* value of the peel changed abruptly from green colour (a*, − 9.44 ± 0.59) at the immature stage to red at the mature stage (a*, 3.13 ± 1.03), and then, to reddish-purple (a*, 5.36 ± 0.76 and b* value, − 1.82 ± 0.30) at the ripe stage and dark purple at the over-ripe stage. Therefore, the stages of fruit maturity strongly influenced the biochemical and antioxidant properties of the fruits and also indicated the ideal harvesting period for obtaining fruits of optimum quality.