Alterações bioquímicas durante o amadurecimento dos frutos de Eugenia astringens e E. uniflora, Myrtaceae nativas da floresta atlântica

Abstract

Myrtaceae species native to the Atlantic Forest in the North-eastern Brazil produce fleshy fruit that are able to display chromatic variations during ripening. Considering that it is still unknown if these multichromatic displays are markers of nutrient availability to seed dispersers, the aim of this work is to verify if changes in water content, dry weight, soluble sugars, starch, soluble proteins, free amino acids, and soluble phenolics during fruit ripening in Eugenia astringens and E. uniflora are related to colour changes. Thus, fruit of E. astringens and E. uniflora were harvested after the expansion phase; for E. astringens, fruits were collected at the yellow, red, and black stage, while for E. uniflora fruit were obtained in stages green, orange, and red. In E. astringens fruit, no changes in the dry weight were verified along ripening, but black fruit presented higher contents of soluble sugars and soluble phenolics than yellow and red fruits. Conversely, orange and red fruits of E. uniflora showed higher dry weight than the green ones, due to dehydration. However, this multicolour display was not associated to the accumulation of soluble sugars, starch, soluble proteins, free amino acids, and soluble phenolics.