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Grape pomace is a source of anthocyanins, which can prevent cardiovascular diseases due to their antioxidant properties. Anthocyanin activity is associated with the ability to regulate oxidative stress through the transcription factor Nrf2. Thus, the present study aimed to evaluate if the anthocyanins found in Pinot noir pomace extract can affect the target genes related to the Nrf2 signalling pathway in endothelial cells. Our results highlight that the predominant anthocyanin in the Pinot noir pomace extract was malvidin-3-glucoside (3.7 ± 2.7 Eq. Malv-3-glu/kg). Molecular docking indicated that cyanidin-3-glucoside (-6.9 kcal/mol), malvidin-3-glucoside (-6.6 kcal/mol) and peonidin-3-glucoside (-6.6 kcal/mol) showed the highest affinities for the binding sites of the BTB domains in Keap1, suggesting that these components may modify the interaction of this protein with Nrf2. In addition, when HUVEC cells were exposed to different concentrations of Pinot noir pomace extract (100 µg/mL, 200 µg/mL, and 400 µg/mL), no changes in Nrf2 gene expression were observed. However, the gene expression of HO-1 and NQO1, which are in the signalling pathway of this transcription factor, increased according the concentrations of the extract (p = 0.0004 and p = 0.0084, respectively). In summary, our results show that anthocyanins play a very important role in Nrf2 activation and release, while at the same time not promoting its transcription. These preliminary results strongly suggest that the Pinot noir pomace extract can serve as a potent bioactive component source that protects cells against oxidative stress.

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Although polyphenols have great pharmacological potential, the main disadvantage is that they have low bioavailability at the desired site. Thus, the use of biocompatible systems for drug delivery is a strategy that is currently gaining great interest. The objective of this study is to evaluate the effect of microencapsulation of caffeic acid and pinocembrin on the antioxidant and antiangiogenic activity of both polyphenols, by the use of nPSi-ßCD composite microparticles. For this HUVEC, cells were exposed to H2O2 and to treatments with polyphenols in solution and loaded in the composite microparticle. The polyphenols were incorporated into a microparticle using nanoporous silicon, chitosan and a ß-cyclodextrin polymer as the biomaterial. The evaluation of the antiangiogenic effect of the treatments with polyphenols in solution and microencapsulated was carried out through functional tests, and the changes in the expression of target genes associated with the antioxidant pathway and angiogenesis was performed through qPCR. The results obtained show that the caffeic acid and pinocembrin have an antioxidant and antiangiogenic activity, both in solution as microencapsulated. In the caffeic acid, a greater biological effect was observed when it was incorporated into the nPSi-ßCD composite microparticle. Our results suggest that the nPSi-ßCD composite microparticle could be used as an alternative oral drug administration system.

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BACKGROUND: Tomato is widely consumed throughout the world for its flavor and nutritional value. This functional food largely depends on the implementation of new strategies to maintain the nutraceutical value, e.g. lycopene concentration, and overcome the challenges of sustainable production and food security. The use of arbuscular mycorrhizal fungi (AMF)-based biostimulants represents one of the most promising tools for sustainable management of agricultural soils, being fundamental for organic food production, reducing fertilizers and pesticides use, and decreasing environmental damage. This study aimed at elucidating whether native arbuscular mycorrhizal fungi (AMF) could positively affect tomato yield and lycopene concentration. RESULTS: Native AMF inoculum consisted of two inoculum types: the single species Claroideoglomus claroideum, and a mix of Scutellospora calospora, Acaulospora laevis, Claroideoglomus claroideum, and Claroideoglomus etunicatum. At the end of the study up to 78% of the root system was colonized by single inoculum. Tomato diameters in single and mix mycorrhizal plants showed increases of 80% and 35% respectively. Fresh weights were 84% and 38% higher with single and mix inocula compared with the controls, respectively. The lycopene concentration in tomato fruits of plants with single and mix inoculum was higher than controls. The lycopene concentration was 124.5% and 113.9% greater in single and mix than non-inoculated plants. CONCLUSION: Tomato diameters, fresh weight and lycopene concentration was significantly higher in plants colonized by AMF compared with uninoculated plants. Results suggest that the role of single species Claroideoglomus claroideum could generate better plant performance due to its high production of extraradical mycelium. © 2021 Society of Chemical Industry.

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The biological properties of chilean propolis have been described and include antibacterial, antifungal and antibiofilm activities. Propolis has a strong antimicrobial potential. Clinical experiences with synthetic antibiotics indicated the need to discover new sources of bioactive compounds associated with ethnopharmacological knowledge or natural sources such as propolis. The microscopic analysis of pollen grains from plants allows us to determine the botanical origin of the propolis samples. In Angol, sample pollen grains were obtained from fodder plants (Sorghum bicolor; Lotus sp.) and trees, such as Acacia sp., Pinus radiata, Eucalyptus sp. and Salix babylonica. Propolis from the Maule region contains pollen grains from endemic plants such as Quillaja saponaria. Finally, the sample obtained from Melipilla presented a wider variety of pollen extracted from vegetable species.Colorimetric assays performed to quantify the total polyphenols present in Chilean propolis samples established that PCP2 (Angol sample) showed high amounts of phenolics compounds, with significant statistical differences in comparison with the other samples. The main compounds identified were pinocembrin, quercetin and caffeic acid phenethyl ester (CAPE). The Angol sample showed a high content of polyphenols.Studies that determine the influence of geographical and floral variables on the chemical composition of propolis are a valuable source of information for the study of its biological properties.

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Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants found in the air generated mainly by the combustion of coal or biomass burning. Exposure to Polycyclic Aromatic Hydrocarbons is positively correlated with cardiovascular diseases. Phenolic compounds are widely found in the plant kingdom, and their availability from agri-food processing waste has led to an increased interest in their recovery. The production of large amounts of organic waste created by the wine industry has emphasized the valuation of these wastes to generate high-added-value by-products. The objective of this work was to investigate the protective effect of Pinot noir pomace extract on human endothelial cells against PAHs found in the polluted air of Temuco, Chile. The pomace extract was characterized by spectrophotometric analysis and high-performance liquid chromatography (HPLC). Results revealed the presence of 5 glycosylated anthocyanins and 9 low molecular weight polyphenols. Molecular docking indicated that cyanidin-3-glucoside (-9.2 kcal/mol) and quercetin (-9.6 kcal/mol) had the highest affinities for the Nrf2 binding site in the Keap1 protein, suggesting a possible competition with this transcription factor. Endothelial cells from the human umbilical vein were exposed to increasing concentrations of Phenanthrene, Fluoranthene, and Pyrene diluted in DMSO in a ratio of 3:1:1 (10 µM-200 µM). Viability through the MTS assay showed that 150 µM of PAHs was sufficient to reduce viability by 75% (p ˂ 0.0001). When the cells were pre-treated with 400 µg/ml of the extract, 150 µM of PAHs did not exert cell death (80% viability). Our preliminary results show that polyphenolic components found in Pinot noir pomace might have a beneficial effect as a protective agent.

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Several biological activities have been reported for the Chilean propolis, among their antimicrobial and antibiofilm properties, due to its high polyphenol content. In this study, we evaluate alternative methods to assess the effect of Chilean propolis on biofilm formation and metabolic activity of Streptococcus mutans (S. mutans), a major cariogenic agent in oral cavity. Biofilm formation was studied by using crystal violet and by confocal microscopy. The metabolic activity of biofilm was evaluated by MTT and by flow cytometry analysis. The results show that propolis reduces biofilm formation and biofilm metabolic activity in S. mutans. When the variability of the methods to measure biofilm formation was compared, the coefficient of variation (CV) fluctuated between 12.8 and 23.1% when using crystal violet methodology. On the other hand, the CV ranged between 2.2 and 3.3% with confocal microscopy analysis. The CV for biofilm's metabolic activity measured by MTT methodology ranged between 5.0 and 11.6%, in comparison with 1.9 to 3.2% when flow cytometry analysis was used. Besides, it is possible to conclude that the methods based on colored compounds presented lower precision to study the effect of propolis on biofilm properties. Therefore, we recommend the use of flow cytometry and confocal microscopy in S. mutans biofilm analysis.

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BACKGROUND: Osteoarthritis (OA) is a progressive and multifactorial disease that is associated with aging. A number of changes occur in aged cartilage, such as increased oxidative stress, decreased markers of healthy cartilage, and alterations in the autophagy pathway. Propolis extracts contain a mixture of polyphenols and it has been proved that they have high antioxidant capacity and could regulate the autophagic pathway. Our objective was to evaluate the effect of ethanolic extract of propolis (EEP) on chondrocytes that were stimulated with IL-1ß. METHODS: Rabbit chondrocytes were isolated and stimulated with IL-1ß and treated with EEP. We evaluated cell viability, nitric oxide production, healthy cartilage, and OA markers, and the expression of three proteins associated with the autophagy pathway LC3, ATG5, and AKT1. RESULTS: The EEP treatment reduces the expression of LC3, ATG5, and AKT1, reduces the production of nitric oxide, increases the expression of healthy markers, and reduces OA markers. CONCLUSIONS: These results suggest that treatment with EEP in chondrocytes that were stimulated with IL-1ß has beneficial effects, such as a decrease in the expression of proteins associated with autophagy, MMP13, and production of nitric oxide, and also increased collagen II.

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The production of reactive oxygen species (ROS) in boar spermatozoa increases in refrigeration; this can have an impact on sperm quality and fertilization capacity. We evaluated the effect of polyphenol-rich aqueous extract of murtilla (Ugni molinae Turcz) on boar sperm stored at 17°C in order to reduce oxidative stress and improve sperm quality in the long term. Five experiments were performed: first, characterization of the polyphenol content from five genotypes of murtilla; second, determination of the genotype with the best antioxidant effect (MT-Ex); third, the antioxidant capacity on O2 - and lipid peroxidation; fourth, the influence of MT-Ex on motility, calcium movement, cAMP, and metabolic parameters; and fifth, analysis of long-term refrigeration. The average phenolic content was 344 ppm; gallic acid, catechin, quercetin, myricetin, and kaempferol were detected. All extracts evaluated presented a concentration-dependent antioxidant effect. MT-Ex reduces intracellular O2 -/peroxides but low lipid peroxidation. MT-Ex in nonstimulated ROS conditions reduces sperm motility, mitochondrial membrane potential, cAMP, and ATP, but the succinate dehydrogenase activity remained normal; also, we observed a reduction in calcium movement in in vitro sperm capacitation. The long-term analyses showed that MT-Ex improved sperm motility decay and reduced membrane damage and ROS at 168 h. Based on this study, we propose MT-Ex as a supplement in semen extenders.

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Dental caries is multifactorial disease and an important health problem worldwide. Streptococcus mutans is considered as a major cariogenic agent in oral cavity. This bacteria can synthetize soluble and insoluble glucans from sucrose by glucosyltransferases enzymes and generate stable biofilm on the tooth surface. Biological properties of Chilean propolis have been described and it includes antimicrobial, antifungal, and antibiofilm activities. The main goal of this study was to quantify the concentrations of main flavonoids presents in Chilean propolis and compare some biological properties such as antimicrobial and antibiofilm activity of individual compounds and the mixture of this compounds, against S. mutans cultures. Chilean propolis was studied and some polyphenols present in this extract were quantified by HPLC-DAD using commercial standards of apigenin, quercetin, pinocembrin, and caffeic acid phenethyl ester (CAPE). MIC for antimicrobial activity was determined by serial dilution method and biofilm thickness on S. mutans was quantified by confocal microscopy. Pinocembrin, apigenin, quercetin, and caffeic acid phenethyl ester (CAPE) are the most abundant compounds in Chilean propolis. These polyphenols have strong antimicrobial and antibiofilm potential at low concentrations. However, pinocembrin and apigenin have a greater contribution to this action. The effect of polyphenols on S. mutans is produced by a combination of mechanisms to decrease bacterial growth and affect biofilm proliferation due to changes in their architecture.

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Propolis is a substance manufactured by Apis mellifera and has been widely used in folk medicine due to its high concentration of bioactive compounds. The purpose of the following study was to characterize and evaluate in vitro the antimicrobial properties of propolis on clinical samples and ATCC strains. The chemical characterization of propolis presents a concentration of total polyphenols of 247 ± 9 mg EAG g-1 MS, flavones and flavonols 75± 4 mg EQ g-1 MS, flavanonones and flavanonols 118 ± 11 EP g-1 MS. HPLC-DAD identified apigenin, galangin, phenethyl ester of caffeic acid and pinocembrin, in addition to 16 compounds by HPLC MS/MS. Chilean propolis is a natural antimicrobial, showing effectiveness in strains ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum and clinical samples of Staphylococcus aureus unlike Escherichia coli. These results demonstrate the antimicrobial effectiveness of the synergy of compounds present in propolis against different human pathogens.

El propóleos es una substancia fabricada por Apis mellifera y ha sido utilizado ampliamente en la medicina popular debido a su alta concentración de compuestos bioactivos. El propósito del siguiente estudio fue caracterizar y evaluar in vitro las propiedades antimicrobianas del propóleos sobre muestras clínicas y cepas ATCC. La caracterización química de propóleos presenta una concentración de polifenoles totales de 247 ± 9 mg EAG g-1 de MS, flavonas y flavonoles 75 ± 4 mg EQ g-1 de MS, flavanononas y flavanonoles 118 ± 11 EP g-1 de MS. Mediante HPLC-DAD se identificó apigenina, galangina, fenetil éster del ácido cafeico y pinocembrina, además de 16 compuestos mediante HPLC MS/MS. El propóleos chileno es un antimicrobiano natural, observándose efectividad en cepas ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum y muestras clínicas de Staphylococcus aureus a diferencia de Escherichia coli. Estos resultados demuestran la efectividad antimicrobiana de la sinergia de compuestos presentes en el propóleos ante diferentes patógenos humanos.

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