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The polyphenol-enriched extracts (PEEs) of Chilean currants Ribes magellanicum and R. punctatum were submitted to in vitro gastro-intestinal digestion and their anti-inflammatory activities were assessed using differentiated human Caco-2 (clone C2BBe1) cells stimulated with interleukin 1β (IL-1 β). The inhibitory effect of non-digested and digested PEEs towards human cyclooxygenase 1 (COX-1) and COX-2, and the gene expression of COX-2 and inducible nitric oxide synthase (iNOS) was also evaluated. The digested PEE from R. punctatum decreased the secretion of IL-8, IL-6, and TNF-α; whereas R. magellanicum reduced IL-6 and TNF-α in the Caco-2 cells (p

Sicana odorifera is a native fruit of South America large in size. Its dark-colored skin constitutes a useful byproduct for obtaining bioactive molecules because it is rich in polyphenolic compounds, such as anthocyanins. Obtaining appropriate extracts for obtaining anthocyanins can be useful for multiple applications in the food industry or for obtaining phytopharmaceuticals. In this work, the fruit and its peel composition were evaluated, an anthocyanin extraction system was designed and optimized, and the extract obtained was characterized. The peel composition of S. odorifera ripe fruits from the black accession growing in Paraguay was rich in polyphenol compounds and anthocyanins. Ultrasound-assisted extractions of total anthocyanins were studied, and the extraction variables were optimized. First, a screening design was considered to analyze time, pH, liquid–solid ratio, solvent concentration, and temperature. From the screening design, the significant variables were considered in a Box–Behnken design, and a response surface methodology was applied. The resulting total anthocyanin extract was characterized by UPLC-DAD-MS / MS-ESI. The most efficient system for the extraction of anthocyanins from the peel was at 15 min, 20 °C, pH = 6, 60% ethanol, and 80 mL/g of liquid–solid ratio. The highest concentration obtained was 61.908 mg C3G/g peel extract. In the extract, 12 main compounds were tentatively identified, including five anthocyanin derivatives, five flavonol derivatives, and two flavonol aglycones. This study provides information for the obtention of an anthocyanin-based dye from black kurugua peel, possibly useful for future applications as a natural colorant in high-added-value foods due to its antioxidant characteristics.

The Araucaria araucana kernels are a traditional food in southern Chile and Argentina. The aim of this work was to determine the composition of the phenolic-enriched extracts (PEEs) of the boiled kernels as well as their antioxidant capacity, inhibitory activity on metabolic syndrome-associated enzymes and effect on postprandial oxidative stress in a simulated gastric digestion model. The PEEs composition was assessed by HPLC-DAD-MS/MS. The main PEEs constituents were catechin and epicatechin in the unbound form, while hydroxybenzoic acids occurred mainly in the bound form. The unbound phenolics from boiled kernels showed significant correlations with DPPH, FRAP, TEAC (Pearson’s r of 0.481, 0.331 and 0.417, respectively) and lipid peroxidation (r = 0.381) and were more active than the bound phenolics. The extracts were highly active against α-glucosidase (IC50: 0.33–3.15 µg/mL) and reduced lipoperoxidation. Traditional processing increases the flavan-3-ol content. Our results suggest that this traditional food has potential health promoting properties.

The protective effect of polyphenols from Chilean currants (Ribes spp.) in human epithelial gastric cells (AGS) against oxidative induced-stress has been recently reported. The aim of the present study was to assess the ability of polyphenol-enriched extracts (PEE) from three Chilean Ribes species to modify the activities of the intracellular antioxidant enzymes: catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-R) and superoxide dismutase (SOD) in AGS cells. The PEE of each species was fractionated using membrane chromatography to give an anthocyanin-enriched fraction (AF) and a copigment fraction (CF). A significant increase in the SOD activity was observed with a dose-response effect after an overnight incubation of AGS cells with the PEE, AF and CF from the selected species. The activity of CAT was enhanced by the CF of Ribes magellanicum and R. cucullatum, and by the AF of R. punctatum. For the GSH-R, a dose-response effect was observed in the extracts of R. magellanicum, while for the GSH-Px activity, only the AF of R. magellanicum and R. cucullatum had a significant increase. The studied samples were not able to increase the intracellular GSH content. Only the R. magellanicum samples raised the intracellular total antioxidant activity. These results suggested that the increase in the activity of the antioxidant response enzymes is associated with the cytoprotective effect of these native currants.

The Chilean wild currants Ribes magellanicum and R. punctatum are a good source of polyphenols. Polyphenolic-enriched extracts (PEEs) from both species were submitted to in vitro colonic fermentation to assess the changes in phenolic composition, antioxidant capacity and inhibition of metabolic syndrome-associated enzymes. The phenolic profiles of the fermented samples showed significant changes after 24 h incubation. Nine metabolites, derived from the microbial fermentation, were tentatively identified, including dihydrocaffeic acid, dihydrocaffeoyl-, dihydroferuloylquinic acid, 1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl)propan-2-ol (3,4-diHPP-2-ol), among others. The content of anthocyanins and hydroxycinnamic acids was most affected by simulated colonic conditions, with a loss of 71–92% and 90–100% after 24 h incubation, respectively. The highest antioxidant capacity values (ORAC) were reached after 8 h incubation. The inhibitory activity against the enzyme α-glucosidase was maintained after the fermentation process. Our results show that simulated colonic fermentation exerts significant changes on the polyphenolic composition of these berries, modifying their health-promoting properties.

The wild Chilean currants Ribes magellanicum and R. punctatum are a good source of polyphenolic compounds. The effect of simulated gastrointestinal digestion (GID) on phenolic content, composition and antioxidant capacity was determined. The inhibitory activity of the non-digested and digested samples towards metabolic syndrome-associated enzymes (α-amylase, α-glucosidase and lipase) was evaluated. The total phenolic (TP) and flavonoid contents (TF) decreased by about 50% at the end of the in vitro GID. Main anthocyanins and hydroxycinnamic acids were strongly affected by this process, with a loss of about 80%. A decrease in the antioxidant activity was observed throughout the digestion steps, which was correlated with the reduction in the TP and TF content. After the in vitro GID of the samples, only the inhibition of α-glucosidase was preserved. Our results show that the simulated GID modified the health-promoting properties of the studied currants.

International audience; Roasted cotyledons of the Chilean hazelnut (Gevuina avellana) are appreciated as snacks. The aim of our work was to assess the fatty acid, oxylipin and phenolic composition using gas chromatography (GC) coupled to mass spectrometry (MS), ultra- high performance liquid chromatography (UHPLC) coupled to MS and HPLC coupled to diode array detector (HPLC-DAD). Additionally, various antioxidant activities were assessed. The inhibition of α-glucosidase, α-amylase, lipase, cyclooxygenases-1 and -2 (COX-1/COX-2), and lipoxygenase was determined. The main fatty acids were oleic and 7-hexadecenoic acids. Eight phytoprostanes and three phytofurans were identified and quantified. Hydroxybenzoic and hydroxycinnamic acids were the main phenolic compounds. Oils showed antioxidant activity determined by EPR, and inhibition of COX-1/COX-2. The statistical analysis showed that the roasting does not affect the composition of the samples. The occurrence of oxylipins in this species is reported for the first time. Chilean hazelnuts can be considered a source of health promoting compounds.

Chilean currants (Ribes magellanicum and Ribes punctatum) are wild polyphenol-rich berries with interesting bioactivities in several in vitro models. The aim of this study was to investigate the effects of the pre-digested PEE (polyphenol-enriched extract) in a simulated colon model. Fruits were extracted, submitted to simulated gastrointestinal digestion and further colonic fermentation with feces from healthy human donors. Samples were taken at 1, 4, 8 and 24 h of incubation, monitoring pH, ammonia, branched-chain fatty acids (BCFA), short-chain fatty acids (SCFA) and bacterial growth. FOS (fructooligosaccharides) and fecal slurry without treatments were positive and negative control, respectively. Both Ribes species reduced (p < 0.05) both BCFA and SCFA at 24 h. R. punctatum promoted the growth (p < 0.05) of beneficial bacteria such as Clostridium cluster XIVa, and Faecalibacterium prausnitzii; while a trend to increase Akkermansia muciniphila was observed. R. magellanicum increased (p < 0.05) Clostridium cluster XIVa population. Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. remained unaffected. Our results suggest that polyphenols from R. punctatum and R. magellanicum may modulate both bacterial metabolism and some selected gut beneficial bacteria under simulated conditions. Therefore, Chilean currants might be useful as supplements to maintain a healthy colon; however, further in vivo studies are needed to confirm their effect and their mechanisms. Ministry of Economy and Competitiveness Ramón y Cajal Fellowship 2012_11910 MINECO (Project AGL2016-75878-R) National Commission for Scientific and Technological Research of Chile CONICYT-PCHA/Doctorado Nacional/2015-21151561 6.475 JCR (2020) Q1, 9/143 Food Science and Technology 1.479 SJR (2020) Q1, 16/332 Food Science No data IDR 2020 UEM

The Chilean white strawberry (Fragaria chiloensis spp. chiloensis f. chiloensis) is a semi-domesticated strawberry with high polyphenol content and antioxidant activity occurring in southern Chile. The aim of this work was to compare the composition and bioactivity of the polyphenol-enriched fruit extract (PEE) before and after simulated gastrointestinal digestion (GID). Results show a decrease by >50% in the total phenolic (TP) content at the end of the GID, compared to the non-digested PEE. A reduction in the antioxidant capacity of the PEEs was observed after GID by means of DPPH, FRAP, TEAC and anion superoxide assays. After simulated GID the PEE significantly inhibited α-glucosidase with an IC50 value of 3.13μg/mL. The inhibition of pancreatic lipase was reduced by 95% after GID. All the PEEs did not show inhibitory effect towards α-amylase throughout the GID. In the same way, the PEEs did not significantly protect human gastric adenocarcinoma (AGS) cells against H2O2-induced stress. Thirty eight compounds were tentatively identified in the non-digested PEE. The compounds that were more affected by the simulated GID were simple phenolics. After the GID, only 33 and 25 compounds were detected, in the gastric and intestinal steps, respectively. These results evidence the changes elicited by GID on the bioactivity and polyphenolic composition of the white strawberry.