The objective of this study was to determine the phenolic compound contents and evaluate the in vitro antioxidant capacity of the following extracts from tropical fruit pulp wastes: acerola (Malpighia glabra L.), guava (Psidium Guayaba L.), pineapple (Ananas comosus L.), cupuaçu (Theobroma grandiflorum), bacury (Platonia insignis), and cherimoya (Annona muricata L.) using the DPPH and ABTS+ radical capture methodologies. The results showed high levels of phenolic compounds in the aqueous and hydroalcoholic extracts of the acerola pulp wastes, of 247.62 ± 2.08 mg.100 g-1 and 279.99 ± 3.5 mg.100 g-1, respectively (p < 0.05). The antioxidant activity, when measured by the DPPH method, showed that the hydroalcoholic extract of the guava wastes presented the highest values with an EC50 of 142.89 μg.mL-1, followed by the hydroalcoholic and aqueous extracts of the acerola wastes, with EC50 values of 308.07 and 386.46 μg.mL-1, respectively. When the antioxidant activity was evaluated by the ABTS method, the acerola pulp wastes showed the highest antioxidant capacity, with TEAC values of 0.518 ± 0.103 and 0.743 ± 0.127 mM.g-1 of residue for the aqueous and hydroalcoholic extracts, respectively (p < 0.05). Thus, the fruit pulp wastes studied in this work, especially acerola and guava, represented potential sources of phenolic compounds, apart from possessing significant in vitro antioxidant capacity, the levels varying according to the residue studied.
Antioxidant capacity; DPPH; ABTS; Total phenolics; Agro-industrial wastes
