Perfil químico do pericarpo de pequi (Caryocar brasiliense Camb.) in natura e na forma de farinha e o efeito da digestibilidade in vitro na bioacessibilidade dos compostos fenólicos.

Abstract

The aim of the present study was to identify the volatile organic compounds (VOCs) present in the pequi pericarp and to produce flours from this agro-industrial residue and to characterize them in terms of their chemical composition, acetylcholinesterase inhibitory activity, chemical profile and their antioxidant potential before and after the in vitro digestibility process, aiming at the full use of the fruit. Initially, the optimization of the extraction method of volatile organic compounds present in the pequi pericarp using HS-SPME/GC-MS involved the evaluation of the parameters: fiber type (PDMS/DVB and DVB/CAR/PDMS), extraction temperature (25, 45 and 65 ºC), extraction time (20, 30 and 40 minutes) and agitation (0, 50 and 100 rpm). Then, flours from the pequi pericarps were prepared and the proximate composition and acetylcholinesterase inhibitory activity of the flours were determined. Subsequently, the chemical profile of the compounds present in the flours was determined using mass spectrometry by paper spray ionization (PS-MS) and the simulated in vitro digestion technique was used to evaluate the bioaccessibility of the phenolic compounds and changes in the antioxidant activity of the samples. The best analytical condition for the extraction of VOCs was obtained using the PDMS/DVB fiber, without agitation, at 65 ºC for 40 min. 35 compounds present in the pequi pericarp were extracted and identified, belonging mainly to the chemical classes of terpenes (65.71%) and esters (14.29%). The pequi pericarp flours proved to be superior in comparison to the fruit pulp in terms of protein, ashes and dietary fibers content, and were classified as potent acetylcholinesterase inhibitors. 46 chemical compounds were identified using the PS-MS technique, such as amino acids, sugars, organic acids and several types of phenolic compounds. In addition, the results obtained in the present study demonstrated an increase in the bioaccessibility of phenolic compounds after in vitro digestibility, contributing to further increase the antioxidant activity of the samples. It was concluded that the pequi pericarp flour has the potential to be used in the development of new food products or as a raw material for the extraction of bioactive compounds, thus contributing to the generation of new jobs, reduction of food waste and use of compounds important for health.