Impact of infusion time and ultrasound-assisted extraction on bioactive compounds and antioxidant capacity of foods prepared from seeds and leaves of Ramon tree (Brosimum alicastrum)

The objective of the present work was to analyse the concentrations of bioactive compounds, and the antioxidant capacity of three foods prepared from the seeds and leaves of Ramon tree (Brosimum alicastrum). We studied the effect of infusion time and ultrasonic extraction on leaves, roasted seeds (coffee substitute), and Ramon flour to optimise the recovery of bioactive components. Infusion time positively affected the concentrations of total phenolic content (TPC), total flavonoid content (TFC), total tannins (TCT), and glycosylated flavonoids (TFG) in the leaves and seeds. The amount of solubilised phenolic compounds increased with increasing infusion time until 2,552 mg of TPC, 54.1 mg of TFC, 75.3 mg of TFG, and 2.40 mg of TCT were obtained per 100 g of leaves. We reported 32.9% greater infusion of toasted seeds in TPC, 87.3% in anthocyanins, 84.6% in TCT, and 91.5% in vitamin C than in leaves. Furthermore, the antioxidant capacity of the seed infusions was 56% greater than that of the leaf infusions. The ultrasonication time was positively correlated with the tannin concentration, which was 43.8% greater in the leaves (5.24 mg/100 g) than in the flour. The neutralising capacity of free radicals determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) was 23.6% greater than that of flour (27.93 µmol/g) and leaves (6.48 µmol/g), and was not related to the extraction time. Taken together, these findings showed that Ramon seeds and leaves could be highly functional foods due to their nutritional quality and high content of antioxidant compounds.