Chemical composition and biological activities of Juçara (Euterpe edulis Martius) fruit by-products, a promising underexploited source of high-added value compounds

Abstract

A B S T R A C TThe pulp of the fruits of Juçara (Euterpes edulis Martius), a native tree of the Atlantic Rainforest of Brazil, is widely consumed thanks to its flavour and nutritional value. The industrial production of Juçara fruit pulp generates solid residues (peel) which are usually discarded. In this work, a hydroalcoholic extract from Juçara peel flour was evaluated for its phenolic profile as well as for its bioactivities. A total of nineteen phenolic compounds were identified in the Juçara peel flour. Among these, seventeen were non-anthocyanin phenolic compounds, namely two phenolic acids, four flavanonols, six flavones, and five flavonols; whereas the two anthocyanin molecules were cyanidin glycoside derivatives. The Euterpe edulis peel flour presented antioxidant activity and antibacterial potential but was not hepatotoxic. These observations corroborate the idea that this byproduct could fit well into the circular bioeconomy concept, thus promoting the Juçara fruit production chain.

By-Products of Camu-Camu [Myrciaria dubia (Kunth) McVaugh] as Promising Sources of Bioactive High Added-Value Food Ingredients: Functionalization of Yogurts

“…Our extracts displayed MIC values above 1.6 mg/mL for almost all the microorganisms tested ( Table 2), results that, in accordance to some authors, are features of weak inhibitors [28]. One should consider that the bacteria strains applied in our tests are clinical isolates of multi-resistant strains, which present significantly higher antibiotic resistance profiles than bacterial strains from American Type Culture Collection (ATCC).…”

“…The application of plant extracts as additives and/or nutraceuticals mandatorily demands proof of its toxicological features [28]. Indeed, the absence of hepatotoxicity herein confirmed for the camu-camu extracts not only corroborates the above-cited studies, but also endorses their safe use in food systems.…”

“…Kaneshima et al [17] confirmed that acylphloroglucinol and rhodomyrtone are antimicrobial constituents of the M. dubia peel. The antimicrobial responses observed in our study likely come from the multiple mechanisms and synergistic effects of various bioactive phytocomponents of the camu-camu extracts [28]. We believe that the promising antibacterial potential of the peel extract may relate, inter alia, to its composition in derivatives of ellagic acid and myricetin (Table 1).…”

Chemical Composition, Nutritional Value, and Biological Evaluation of Tunisian Okra Pods (Abelmoschus esculentus L. Moench)

“…Regarding the total phenolic content (TPC), A. esculentus pods extract presented a concentration of 4.75 mg. g −1 ( Table 4 ), which unfortunately cannot be compared with other authors. Only Xu et al [ 7 ] investigated the phenolic fractions of several flours obtained from okra seeds and seedless pods; however, the values of TPC were reported in gallic acid equivalents, between 288.2 and 3426.2 mg GAE/100 g. It is known that other groups of molecules (e.g., reducing sugars) found in important amounts in vegetable extracts can also reduce the Folin Ciocalteu reagent, consequently producing overestimated values of TPC via this method [ 21 ].…”

“…The FRAP (ferric reducing antioxidant power) assay takes advantage of electron-transfer reaction. The transfer of the electron from the antioxidant to the probe resembles the redox titration in classical chemical analysis, because there is not a competitive reaction involved and there is no oxygen radical in the assay [ 21 ]. β-carotene bleaching assay is also a common way to evaluate the antioxidant potential of hydroxylated fullerenols.…”