Examinando por Autor "Sepúlveda, B."
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Ítem Azorella compacta infusion activates human immune cells and scavenges free radicals in vitro(Medknow Publications, 2017) Tumová, L.; Dučaiová, Z.; Cheel, J.; Vokřál, I.; Sepúlveda, B.; Vokurková, D.Background: Azorella compacta is traditionally used in the form of tea (infusion), in the Andean region of South America, to treat various chronic diseases. However, the health-promoting properties of this herbal tea have not yet been extensively explored. Materials and Methods: The free radical scavenging activity of A. compacta infusion (ACI) was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and superoxide anion radical assays. The activation of immune cells by ACI, as determined by cell surface cluster of differentiation 69 expression, was measured by flow cytometry. The qualitative polyphenolic composition of ACI was investigated by HPLC/PDA/ESI-MS, (High-performance liquid chromatography coupled with photodiode array detection and electrospray ionization-mass spectrometry) and the total content of polyphenols was estimated by spectrophotometric methods. Results: Eight polyphenols including chlorogenic acid, 6,8-di-C-hexosyl apigenin, isoorientin, orientin, dicaffeoylquinic acid, biochanin A-O-glucoside, biochanin A-O-(malonyl)-glucoside, and licoisoflavone A were tentatively identified in ACI. The total contents of phenols, flavonoids, and tannins in lyophilized ACI were 5.40 mg/100 mg ACI, 1.79 mg/100 mg ACI, and 1.76 mg/100 mg ACI, respectively. ACI, within the range of 25-400 μg/mL, scavenged DPPH and O2 .- by 15-90% and 20-88%, respectively. The human natural killer (NK) cells were substantially activated by ACI, whereas T cells and granulocytes were slightly stimulated. Conclusion: Overall, the results demonstrate the free radical scavenging and immune-stimulating properties of ACI, and support, at least in part, its potential utilization as a functional herbal tea. for preventing chronic diseases and as a nonspecific immune stimulator during human immunosenescence.Ítem Gastroprotective activity of Parastrephia quadrangularis (Meyen), cabrera from the atacama desert(MDPI AG, 2018-09) Ardiles, A.; Barrientos, R.; Simirgiotis, M.J.; Bórquez, J.; Sepúlveda, B.; Areche, C.Forty-three metabolites including several methoxylated flavonoids, tremetones, and ent-clerodane diterpenes were accurately identified for the first time in the ethanolic extract of P. quadrangularis by means of hyphenated UHPLC-quadrupole Orbitrap mass spectrometry, and seven isolated compounds were tested regarding gastroprotective activity using the HCl/EtOH-induced lesion model in mice. A new tremetone (compound 6) is reported based on spectroscopic evidence. The isolated clerodanes and tremetones showed gastroprotective activity in a mouse model, evidenced by compound 7 (p-coumaroyloxytremetone), which showed the highest gastroprotective activity (76%), which was higher than the control drug lansoprazole (72%). Our findings revealed that several constituents of this plant have gastroprotective activity, and particularly, p-coumaroyloxytremetone could be considered as a lead molecule to explore new gastroprotective agents. This plant is a rich source of biologically active tremetones and terpenoids which can support the ethnobotanical use of the plant. © 2018 MDPI AG. All rights reserved.Ítem Metabolomic Analysis of Two Parmotrema Lichens: P. robustum (Degel.) Hale and P. andinum (Mull. Arg.) Hale Using UHPLC-ESI-OT-MS-MS(MDPI AG, 2017) Torres-Benítez, A.; Rivera-Montalvo, M.; Sepúlveda, B.; Castro, O.N.; Nagles, E.; Simirgiotis, M.J.; Garciá-Beltrán, O.; Areche, C.Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum), a full metabolome study based on ultra-high performance liquid chromatography-diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS) was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens.Ítem Phenolic Profile, Antioxidant and Enzyme Inhibition Properties of the Chilean Endemic Plant Ovidia pillopillo (Gay) Meissner (Thymelaeaceae)(MDPI, 2022-02) Cortés, C.; González-Cabrera, D.; Barrientos, R.; Parra, C.; Romero-Parra, J.; Pertino, M.; Areche, C.; Sepúlveda, B.; Bórquez, J.; Torres-Benítez, A.; Simirgioti, M.Ovidia pillopillo (Lloime) is an endemic species of the Valdivian Forest of Chile. Little is known on the chemistry and biological activity of this plant. In this study, the phenolic profile, antiox-idant capacities and enzyme inhibition capacities (against tyrosinase and cholinesterase) of the plant were investigated for the first time. The phenolic profile of the plant was obtained by UHPLC-MS fingerprinting with high resolution, which showed the presence of several flavonoids and coumarins. The antioxidant potential was measured by FRAP and ORAC (45.56 ± 1.32; 25.33 ± 1.2 µmol Trolox equivalents/g dry plant, respectively) plus ABTS and DPPH methods (IC50 = 9.95 ± 0.05 and 6.65 ± 0.5 µg/mL, respectively). Moreover, the flavonoid and phenolic contents were determined (57.33 ± 0.82 and 38.42 ± 1.32, µg of Trolox and quercetin equivalents/100 g dry weight, respectively). The ethanolic extract showed cholinesterase (IC50 = 1.94 ± 0.07 and 2.73 ± 0.05 µg/mL, for AChE and BuChE, respectively) and tyrosinase (4.92 ± 0.05 µg/mL) enzyme inhibition activities. Based on these in vitro studies, in silico simulations were performed, which determined that the major compounds as ligands likely docked in the receptors of the enzymes. These results suggest that Ovidia pillopillo produce interesting special coumarins and flavonoids, which are potential candidates for the exploration and preparation of new medicines.Ítem UHPLC high resolution orbitrap metabolomic fingerprinting of the unique species Ophryosporus triangularis meyen from the atacama desert, Northern Chile(Sociedade Brasileira de Farmacognosia, 2017-04) Simirgiotis, M.J.; Quispe, C.; Mocan, A.; Villatoro, J.M.; Areche, C.; Bórquez, J.; Sepúlveda, B.; Echiburu-Chau, C.High-resolution mass spectrometry is currently used to determine the mass of biologically active compounds in plants and UHPLC-Orbitrap is a relatively new technology that allows fast fingerprinting and metabolomics analysis. In this work, several phenolic compounds including eleven phenolic acids, two fatty acids, two chromones and fourteen flavones were rapidly identified in the methanolic extracts of aerial parts and flowers of the unique Chilean species Ophryosporus triangularis Meyen, Asteraceae, growing in the Atacama Desert by means of ultrahigh resolution liquid chromatography orbitrap MS analysis (UHPLC-PDA-OT-MS) for the first time. The UHPLC-MS fingerprint generated can be used for the authentication of this endemic species. The methanolic extracts of the aerial parts and flowers showed also antioxidant capacities (65.34 ± 1.32 and 52.41 ± 1.87 μg/ml in the DPPH assay, 184.88 ± 13.22 and 196.80 ± 13.28 μmol TE/g dry weight in the ferric reducing power assay and 56.17 ± 3.03 and 65.41 ± 1.96% in the superoxide anion scavenging assay, respectively).Ítem UHPLC-ESI-ORBITRAP-MS analysis of the native Mapuche medicinal plant palo negro (Leptocarpha rivularis DC.–Asteraceae) and evaluation of its antioxidant and cholinesterase inhibitory properties(Taylor and Francis, 2018-01) Jiménez-González, A.; Quispe, C.; Bórquez, J.; Sepúlveda, B.; Riveros, F.; Areche, C.; Nagles, E.; García-Beltrán, O.; Simirgiotis, M.J.UHPLC/ESI/MS identification of organic compounds is the first step in the majority of screening techniques for the characterization of biologically active metabolites in natural sources. This paper describes a method for the fast identification and characterisation of secondary metabolites in Leptocarpha rivularis DC. (Palo negro) extracts by HPLC/UV (DAD)–Mass Spectrometry (HPLC/MS). The plant is used for the treatment of several diseases since pre-hispanic Mapuche times. Thirty-seven compounds were detected in the aqueous edible extract for the first time including 4 sesquiterpenes, 10 flavonoids, 9 oxylipins, 2 organic acids, and 11 phenolic acids. In addition, phenolic content antioxidant and cholinesterase inhibitory activities were measured for the first time using the edible infusion. The total polyphenol content of the infusion was 230.76 ± 2.5 mmol GAE/kg dry weight, while the antioxidant activity was 176.51 ± 28.84; 195.28 ± 4.83; and 223.92 ± 2.95 mmol TE/kg dry weight, for the DPPH, ABTS, and FRAP assays, respectively. The cholinesterase inhibitory activity was 7.38 ± 0.03 and 5.74 ± 0.06 mmol GALAE/kg, for the inhibition of acetylcholinesterase AChE and BChE, respectively, showing that this plant is a candidate for the isolation of compounds that can be useful for the treatment of neurodegenerative diseases. Furthermore, this plant could serve also as a raw material for the production of dietary supplements, due to its content of polyphenolic compounds. © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.