The aroma compounds contribute to fruits flavor, taste, and nutritional value. These compounds include various chemical classes such as terpenoids, lactones, ketones, esters, acids, alcohols, and their derivatives. Uridine diphosphate-dependent glycosyltransferases (UGTs) modify these compounds by covalently adding one or multiple sugar molecules. This glycosylation process converts volatile, unstable, and hydrophobic aroma compounds into hydrophilic, stable, and slow-releasing reservoirs of fruit flavor. The diversity and spatio-temporal expression patterns of UGTs play a crucial role in forming a wide range of glycosylated aroma compounds. This review focuses on aroma-related compounds in both free and glycosylated-bound forms found in commercial vital fruits. We discuss various fruit-specific UGTs and their role in the glycosylation of aroma compounds. Based on structural and functional information on UGTs, we have assessed sugar donor specificity and the residues responsible for the same. Moreover, phylogenetic analysis of characterized UGTs provides insights into their substrate preferences. We also surveyed the expression dynamics of UGTs during fruit ripening, as the switching between aglycon and glycosylated-bound forms of aroma compounds significantly impacts fruit quality. Potential applications of UGTs in the food and fragrance industry have been discussed. The information reviewed could be beneficial for developing novel methods for flavor manipulation of commercially important glycosides derived from natural resources.

Foreign