Characterization, bioactive compounds and antioxidant potential of three Amazonian species: rambutan (Nephelium lappaceum), tucumã (Astrocaryum aculeatum) and pupunha (Bactris gasipaes)

Amazon forest covers the greatest flora biodiversity in the world and it comprises about 50% of all species that exist today. Unfortunately, a large number of fruits consumed in the Amazonian region are still few studied including their phytochemical composition and antioxidant potential. Among the under-exploited and underutilized fruits of the Amazon, we can mention the tucumã (Astrocaryum aculeatum), pupunha (Bactris gasipaes) and rambutan (Nephelium lappaceum). They are exotic species widely consumed in natura by the Amazonian population and used in folk medicine in the treatment of fever, headache, diabetes and hypertension. Thus, with the objective of stimulating the cultivation and consumption of Brazilian native fruits, as well as the study about their phytochemical characterization and antioxidant potential, three native fruits species from the Amazon were evaluated in this study. Phenolics present in these fruits were for the first time characterized using Mass Spectrometry. This analysis identified 19, 18 and 11 phytochemicals in tucumã, pupunha and rambutan, respectively, belonging to different chemical classes, including phenolic acids, flavonoids, organic acids, and other compounds. Hydroxymethylfurfural, tartaric acid, cinnamic acid, caffeic acid, ferulic acid, galactonic acid, syringic acid, dimethylcaffeic acid, 2-O-p-coumaroyltartronic acid and catechin glucoside were found in all fruits. High levels of total phenolics, flavonoids, condensed tannins and antioxidant activities were found in rambutan, tucumã and pupunha. Thus, the data clearly shows that these amazon fruits could be used as a source of phenolic compounds, and its exploration can contribute to human health and well-being to stimulate their consumption and commercial exploitation.