Enzymatic and ultrasonic-assisted pretreatment in the extraction of bioactive compounds from Monguba (Pachira aquatic Aubl) leaf, bark and seed

摘要

The present study aims to characterize leaf, bark and seed of monguba in terms of their physicochemical and bioactive composition, and to determine total phenolic compounds (TPC) and total flavonoids (TF), well as their antioxidant activities (AA), of three organic solvent extracts with and without enzyme pretreatment by ultrasonic assisted extraction. Physicochemical composition was measured by pH, total titratable acidity, total soluble solids, moisture, ashes, lipids, crude protein, raw fiber, total carbohydrates, and water activity as well as, phytochemical composition analysis constituted of sugars, condensed (CT) and hydrolysable tannins (HT), carotenoids, total anthocyanins (TA), and organic acids contents. TPC and TF contents, and UHPLC/PDA/QDa flavonoids and phenolic acids quantification were performed for the solvent extracts. Antioxidant activity was determined by radical scavenging capacity assays (ABTS, DPPH, and ORAC), and reducing power assay (FRAP). Results showed that the leaf stood out with higher concentrations of ash, HT, TA and carotenoids; the bark with higher concentrations of raw fiber, total carbohydrates and organic acids (tartaric, quinic and 3.4-dihydroxybenzoic acids); in contrast, the seeds showed high concentrations of lipids, crude protein, sugars (fructose and sucrose), CT, and high values in all AA. The solvents significantly influenced the extraction of TPC and TF, highlighting ethanol. In general, the enzymatic treatments empowered the phenolic extraction and AA. The monguba seed extracts showed higher concentrations of hydroxycinnamic acids (chlorogenic acid, mainly), and flavanols (catechin and epicatechin), whereas the leaf extracts, flavanones (narigenin), flavonols (rutin, mainly) and flavones (acacetin). The bark extracts stood out for the presence of vanillin. The monguba seed extract can be used in functional foods production.