Metabolome Reprogramming During Fruit Ripening and Post-Harvest Storage in Ten Crop Species

Plants alter metabolites of their fruits during the ripening process, leading to improved nutritional properties and taste. In addition, metabolite compositions continue to change on the shelf after harvest. However, the dynamics of these important processes are species-specific and so this study aimed to contrast the ripening dynamics of ten different fruit species simultaneously.

Plant material was collected from the fruits of apple, banana, blueberry, kiwifruit, pear, plum, peach, strawberry, raspberry, and tomato at three different stages: unripe, fully ripe, and overripe fruits. Comparative metabolome analysis by GCMS was performed to identify differentially abundant metabolites across the species of this study and to examine their dynamics across ripening and post-harvest storage. These results were complemented by elemental compositions derived from a literature search.

In a first, this study demonstrated that both baseline metabolite abundances and their dynamics across ripening clustered species vary largely according to their phylogeny. Comparisons across ripe fruit identified differences in nutritional properties, highlighting species such as banana to be of especially high nutritional value and blueberry and peach to be prominent sources of antioxidants. Comparing the ripening dynamics of all species identified common patterns, such as the conversion of organic acids to sugars and cell wall dynamics, although species-specific responses were also acknowledged, in particular, kiwi and the Rosaceae berries, which may explain differences in post-harvest shelf-life.

The observed inter- and intra-specific variation in nutritionally relevant metabolites and elements serves as a reference for both producers and consumers and emphasizes that consuming a variety of fruits, not only across species but also across cultivars within a species, can maximize the intake of beneficial phytonutrients, sugars, amino acids, and antioxidants.