Effect of in vitro gastrointestinal digestion on the total phenolic contents and antioxidant activity of wild Mediterranean edible plant extracts

Abstract

The recent interest in wild edible plants is associated to their health benefits, which are mainly due to their richness in antioxidant compounds, particularly phenolics. Nevertheless, some of these compounds are metabolized after ingestion, being transformed into metabolites frequently with lower antioxidant activity. The aim of the present study was to evaluate the influence of the digestive process on the total phenolic contents and antioxidant activity of extracts from four wild edible plants used in the Mediterranean diet (Beta maritima L., Plantago major L., Oxalis pes-caprae L. and Scolymus hispanicus L.). HPLC-DAD analysis revealed that S. hispanicus is characterized by the presence of caffeoylquinic acids, dicaffeoylquinic acids and flavonol derivatives, P. major by high amounts of verbascoside, B. maritima possesses 2,4-dihydroxybenzoic acid, 5-O-caffeoylquinic acid, quercetin derivatives and kaempferol-3-O-rutinoside and O. pes-caprae extract contains hydroxycinnamic acids and flavone derivatives. Total phenolic contents were determined by Folin-Ciocalteu assay, and antioxidant activity by the ABTS, DPPH, ORAC and FRAP assays. Phenolic contents of P. major and S. hispanicus extracts were not affected by digestion, but they significantly decreased in B. maritima after both phases of digestion process and in O. pes-caprae after the gastric phase. The antioxidant activity results varied with the extract and the method used to evaluate the activity. Results showed that P. major extract has the highest total phenolic contents and antioxidant activity, with considerable values even after digestion, reinforcing the health benefits of this species.

Extraction of Antioxidants from Winemaking Byproducts: Effect of the Solvent on Phenolic Composition, Antioxidant and Anti-Cholinesterase Activities, and Electrochemical Behaviour

“…The total phenolic content (TPC) was determined using the Folin–Ciocalteu assay with some modifications [ 31 ]. Firstly, 200 μL of 10% ( v/v ) Folin–Ciocalteu reagent, 100 μL of each phenolic extract and 800 μL of 700 mM Na 2 CO 3 were mixed and incubated in the dark for 2 h at room temperature.…”

“…The capacity of samples to scavenge DPPH radicals was evaluated according to the previous protocol with some modifications [31]. Samples were diluted to an adequate concentration in relation to the Trolox standard (a dilution that produced between 20-80% inhibition of the blank absorbance, which was different depending on the type of extract).…”

“…The ORAC was evaluated as previously described with some modifications [31]. Samples were diluted to an adequate concentration in relation to the Trolox standard (dilution was different for each type of extract).…”

Synthesis of Silver Nanoparticles Using Aqueous Leaf Extract of Mimosa albida (Mimosoideae): Characterization and Antioxidant Activity

“…Mimosa albida (Figure 1) is a plant native to Ecuador. It is known as uña de gato (cat's claw), mimosa, sarza, tapa vergüenza (cover shame) or dormilona (sleepyhead) [35,36]. It is traditionally used in the treatment of heart disease, migraine, insomnia, fever, cough, rheumatism, liver and kidney pain, and as a healing agent [37].…”

Controlling Fusarium oxysporum Tomato Fruit Rot under Tropical Condition Using Both Chitosan and Vanillin

“…They are particularly involved in plant defense against ultraviolet radiation and aggression by a pathogen [41]. Phenolic compounds are probably the most important candidates contributing to the antioxidant properties of plants and are associated with the scavenging of free radicals, breaking radical chain reactions, and chelating metals [42]. In this study, coating treatments had a significant effect on total phenolic content over the entire storage period.…”