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Item Estudio de inhibición de la disfunción endotelial in vitro en celulas endoteliales humanas ea.hy926 por extractos de Phaseolus vulgarisAutores: Blanco Márquez, Nicolás Alejandro; Torres Garrido, Carlos IgnacioProfesor Guía: Wehinger Wehinger, Sergio AntonioEl estudio de la disfunción endotelial es suma importancia debido a las diferentes funciones que poseen las células endoteliales, tales como la regulación de la permeabilidad, constricción e inhibición de la coagulación por parte de los vasos, además de los distintos factores que pueden desencadenar una disfunción endotelial, como las enfermedades crónicas, siendo algunas de estas la diabetes mellitus, hipertensión arterial y obesidad. Es por esto que se busca estudiar el efecto protector que poseen los compuestos bioactivos presentes en distintas especies de porotos cultivados en Chile de la especie Phaseolus vulgaris, entre los que destacan los fenoles y flavonoides que actúan como compuestos antioxidantes frente al estrés oxidativo que se genera en la disfunción endotelial. Es por ello por lo cual se determinó la cantidad total de fenoles que poseían extractos de las diferentes variedades de Phaseolus vulgaris mediante la técnica de Folin-Ciocalteu, además de las concentraciones de flavonoides mediante el método de Zhishen y col, así como la capacidad antioxidante de los extractos de Phaseolus vulgaris mediante DPPH, y capacidad citoprotectora in vitro de 3 especies de Phaseolus vulgaris sobre las células endoteliales humanas EA.hy926. Los resultados obtenidos para fenoles totales fueron mayores en las especies que se extrajeron mediante microondas (MAE) que las especies que fueron extraídas con ultrasonido (UAE). Los extractos presentaron cantidades apreciables de fenoles, a diferencia de los flavonoides, los que, en algunos casos, apenas fueron detectables, siendo la variedad “Negro” la que presentó la concentración de fenoles más alta con 782,8 EqAg/g, siguiendo la de “Hallado Alemán” con 726,9 EqAg/g. En cuanto a los resultados de la capacidad antioxidante por DPPH, la más elevada fue la especie “Frutilla” con un 54,3% en base al control, y por último, para la capacidad citoprotectora in vitro de los extractos, se obtuvo mayores valores de viabilidad en las células que poseían el extracto frente al agente estresante que frente al agente solo. Estos resultados aportan información preliminar y de resultados limitados, pero relevantes como punto de inicio para evaluarla capacidad citoprotectora y antioxidante que presentan los extractos para futuros estudios.Item Inhibition of platelet aggregation by extracts and compounds from the leaves of Chilean bean landraces (Phaseolus vulgaris L.)Autores: Fuentes, Eduardo; Rodríguez, Lyanne; Mendez, Diego; Alarcón-Espósito, Jazmín; Nina, Nelida; Burgos-Edwards, Alberto; Carrasco, Basilio; Palomo González, Iván; Schmeda-Hirschmann, GuillermoLeaf extracts from Chilean bean landraces were assessed for antiplatelet activity using different assays in vitro. Lyophilized MeOH:H2O 7:3 (v/v) and EtOH:H2O 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:H2O 7:3 extracts have higher antiplatelet capacity, with better effects for the Frutilla and Sapito landraces (IC50 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.Item Inhibition of advanced glycation end products and protein oxidation by leaf extracts and phenolics from Chilean bean landracesAutores: Ávila, Felipe; Cruz, Nadia; Alarcón-Espósito, Jazmín; Nina, Nelida; Paillán, Hernán; Marquez, Katherine; Fuentealba, Denis; Burgos-Edwards, Alberto; Theoduloz, Cristina; Vejar-Vivar, Carmina; Schmeda-Hirschmann, GuillermoPhenolics can decrease the levels of advanced glycation end products (AGEs) from proteins, but their mecha-nisms 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 (fluo-rescent AGEs and carboxymethyl lysine) and oxidative (Kyn, Di-Tyr, protein carbonyls) modifications. Fluo-rescent 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.Item Nutritional Characterization of Chilean Landraces of Common BeanAutores: Márquez, Katherine; Arriagada, Osvin; Pérez Díaz, Ricardo; Cabeza Pérez, Ricardo Alfonso; Plaza, Andrea; Arévalo, Bárbara; Meisel, Lee A.; Ojeda, Daniela; Silva, Herman; Schwember, Andrés R.; Fuentes, Camila; Flores, Mónica; Carrasco, BasilioCommon bean (Phaseolus vulgaris L.) is the primary grain legume cultivated worldwide for direct human consumption due to the high nutritional value of its seeds and pods. The high protein content of common beans highlights it as the most promising source of plant-based protein for the food industry. Additionally, landraces of common bean have great variability in nutritional traits, which is necessary to increase the nutritional quality of elite varieties. Therefore, the main objective of this study was to nutritionally characterize 23 Chilean landraces and 5 commercial varieties of common bean to identify genotypes with high nutritional value that are promising for the food industry and for genetic improvement programs. The landrace Phv23 ('Palo') was the most outstanding with high concentrations of minerals such as P (7.53 g/kg), K (19.8 g/kg), Mg (2.43 g/kg), Zn (52.67 mg/kg), and Cu (13.67 mg/kg); essential amino acids (364.8 mg/g protein); and total proteins (30.35 g/100 g seed). Additionally, the landraces Phv9 ('Cimarron'), Phv17 ('Juanita'), Phv3 ('Araucano'), Phv8 ('Cabrita/Senorita'), and Phv4 ('Arroz') had a high protein content. The landrace Phv24 ('Peumo') stood out for its phenolic compounds (TPC = 218.1 mg GA/100 g seed) and antioxidant activity (ORAC = 22,167.9 mu mol eq trolox/100 g extract), but it has moderate to low mineral and protein concentrations. In general, the concentration of nutritional compounds in some Chilean landraces was significantly different from the commercial varieties, highlighting their high nutritional value and their potential use for the food industry and for genetic improvement purposes.
