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• The effect of in vitro gastrointestinal digestion (GID) on Ribes fruits was studied. • The in vitro anti-inflammatory effect of resulting polyphenols after GID was assessed. • The digested extracts reduced the IL-8, IL-6 and TNF-α levels in Caco-2 inflamed cells. • The digested extracts decreased the COX-2 and iNOS gene expression in Caco-2 cells. • The digested Ribes spp. extracts inhibited human COX-1 and COX-2 activity in vitro. 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 < 0.05). Both digested extracts significantly down-regulated the mRNA expression of COX-2 and iNOS (p < 0.05). PEEs showed 60% of inhibition towards COXs, with higher inhibition against COX-2. The PEEs from R. punctatum displayed better anti-inflammatory activity in all the experiments. Our results suggest that R. magellanicum and R. punctatum might be useful against intestine inflammatory conditions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Leaf extracts from Chilean bean landraces were assessed for antiplatelet activity. • The HPLC-DAD study allowed the identification of caffeoyl malic acid, derivatives of quercetin, and kaempferol. • The most active extracts with antiplatelet effect were Frutilla and Sapito landraces. • Antiplatelet activity was associated with the content of rutin, caffeoyl malic acid, and kaempferol 3-O-glucoside. Leaf extracts from Chilean bean landraces were assessed for antiplatelet activity using different assays in vitro. Lyophilized MeOH:H 2 O 7:3 (v/v) and EtOH:H 2 O 7:3 (v/v) leaf extracts from the Chilean landraces Coscorron, Frutilla, Magnum, Sapito and Tortola were compared for platelet aggregation effect by turbidimetry and flow cytometry. The HPLC-DAD study allowed the identification of caffeoyl malic acid, derivatives of quercetin and kaempferol. The results showed that the EtOH:H 2 O 7:3 extracts have higher antiplatelet capacity, with better effects for the Frutilla and Sapito landraces (IC 50 0.38 ± 0.05 and 0.16 ± 0.08 mg/mL, respectively). The Sapito extract inhibited P-selectin expression, CD63 secretion, and concentration-dependent GPIIb/IIIa activation. The activity was associated with the main phenolics content, including rutin, caffeoyl malic acid and kaempferol 3-O-glucoside. The findings add evidence for the potential of bean leaves as greens, affording naturally occurring compounds with health promoting properties, including inhibition of platelet aggregation in vitro. [ABSTRACT FROM AUTHOR]

[Display omitted] • Leaf extracts from six Chilean landraces of Phaseolus vulgaris were investigated. • Some 26 compounds were identified from the most active sample by HPLC-MS/MS. • Pearson's analysis shows strong correlations between phenolics and AGEs inhibition. • Caffeoyl malic acid and rutin synergistically inhibit AGEs and protein oxidation. Phenolics can decrease the levels of advanced glycation end products (AGEs) from proteins, but their mechanisms in complex mixtures are poorly understood. Leaf extracts and the main phenolics from Chilean bean (Phaseolus vulgaris) landraces were assessed for their capacity to inhibit AGEs and oxidative modifications on bovine serum albumin incubated with glucose. The leaf extracts of six bean landraces decreased AGEs (fluorescent AGEs and carboxymethyl lysine) and oxidative (Kyn, Di-Tyr, protein carbonyls) modifications. Fluorescent AGEs were characterized by time-resolved techniques. The composition of the extracts was determined by HPLC-DAD-Q-TOF-MS/MS, and the main compounds were quantified by HPLC. Correlations between the levels of AGEs or protein carbonyls with the main phenolics suggested synergic effects of caffeoyl malic acid (CMA) and rutin. The synergic effect was evaluated using mixtures of rutin and CMA, showing a strong decrease in fluorescent AGEs and protein carbonylation compared with the pure single compounds, supporting this finding. [ABSTRACT FROM AUTHOR]