Ultrasound-assisted extraction of compounds Phenolics from bocaiuva peel (Acrocomia aculeata)

Abstract

Bocaiuva palm (Acrocomia aculeata) is a specie native from tropical forests, commonly found in the Brazilian cerrado, where the economic interest is focused on the exploration of its fruits. The peel of bocaiuva represents 20% of the total mass of the fruit and can be considered as a residue of great food potential due to the presence of bioactive compounds. The ultrasound technique is widely applied in extraction processes, in order to reduce the time and cost of extraction of bioactive compounds from plant matrix. The present work aims to evaluate the influence of the extraction time of the phenolic compounds from the bocaiuva peel using the assisted ultrasound technique. For this, the peels of bocaiuva were dried and ground in mesh 42, homogenized in 50% ethyl alcohol, obtaining the phenolic extracts from the exposure of the mixture in an ultrasonic bath at different extraction times (15, 30, 45 and 60 min). The extracts were evaluated for the contents of total phenolic compounds and, the antioxidant activity, determined by the ABTS and DPPH methods. Thus, it was observed that the extract obtained in 45 min of exposure to ultrasound had a higher content of phenolic compounds (5.46 mg EAG.g^-1) and, consequently, antioxidant activities of 83.89 mg TEAC.g^-1 and 99.24 mg TEAC.g^-1 by ABTS and DPPH methods, respectively. From the results obtained in this study, it was possible to determine that the ideal time for the extraction of phenolic compounds from the bocaiuva bark using ultrasound is 45 min.

Key words: Bioactive compounds. Antioxidant activity. Food waste. Biodiversity.