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Introducción: Phaseolus vulgaris L. (frijol) es una fuente nutricional importante en Colombia, que aporta un gran contenido de sustancias bioactivas con potencial benéfico para la salud, tales como polifenoles, entre otras, que contribuyen de manera sinérgica con sus propiedades terapéuticas, y que pueden tener un efecto positivo contra algunas patologías. Objetivos: evaluar el método de extracción asistido por microondas como método alternativo para estudiar la capacidad antioxidante in vitro en ocho variedades de P. vulgaris L. cultivadas en Colombia. Métodos: semillas sin piel de P. vulgaris, deshidratadas y maceradas se sometieron a extracción asistida por microondas y extracción sólido-líquido; el contenido de fenoles se evaluó por el método de Folin-Ciocalteu y el potencial antioxidante in vitro se evaluó con base en los métodos del radical estable catión radical difenil-picrilhidrazilo y el radical catión 2,2´-azino-bis(ácido 3-etilbenzotiazolin-6-sulfunico). Resultados: el método de extracción asistido por microondas realizada en horno microondas convencional fue más eficiente respecto a la convencional ya que disminuyó la cantidad de solvente, de muestra empleada y los tiempos de extracción. Los extractos obtenidos por extracción asistida por microondas en horno microndas convencional presentaron un contenido de fenoles entre 29,36 y 60,61 g EAG/L, mientras que el método extracción sólido-líquido, estuvo entre 32,75 y 113,27 g EAG/L. El efecto anti-radicalario fue similar entre los extractos evaluados. Conclusiones: todos los extractos presentaron buena capacidad protectora contra radicales libres, y la técnica de extracción asistida por microondas en horno microndas convencional puede ser usada como método alterno para una valoración rápida, eficiente y eficaz del contenido de sustancias bioactivas en diferentes matrices, se presentó mínimas diferencias entre los resultados obtenidos, comparados con las metodologías de extracción asistida por microondas establecidas antes(AU)

Introduction: Phaseolus vulgaris L. is a representative crop of nutrient and economic importance in Colombia. Additionally, P. vulgaris is considered as a natural source of bioactives compounds, such as polyphenols, which have been associated with valuable effects on health. Objetives: to evaluate the microwave extraction assisted technique as an alternative methodology to study the antioxidant capacity of eight varieties of P. vulgaris cultivated in Colombia. Methods: dehydrated and powered seeds of P. vulgaris was subjected to microwave assisted extraction and solid-liquid extraction and. Total phenolis content was determined by Folin-Cicoulteau method and the potential antioxidant was evaluated using diphenyl-picrylhydrazyl radical stable and 2,2-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation assays. Results: microwave assisted extraction-Household microwave oven technique was more efficient and versatile than SLE method. The extracts obtained microwave assisted extraction-Household microwave oven methodology showed polyphenol content ranged between entre 29,36 and 60,61 g EGA/L, but SLE was over 32,75 and 113,27 g EAG/L. Conclusions: all extracts showed a considerable antioxidant potential against free radical, and microwave assisted extraction-Household microwave oven method could be used as an alternative method for fast, efficient and effective evaluation of the content of polyphenol in various matrices, with minimal differences comparing to established microwave assisted extraction techniques(AU)

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Acacia farnesiana lectin-like protein (AFAL) is a chitin-binding protein and has been classified as phytohaemagglutinin from Phaseolus vulgaris (PHA). Legume lectins are examples for structural studies, and this family of proteins shows a remarkable conservation in primary, secondary, and tertiary structures. Lectins have ability to reduce the effects of inflammation caused by phlogistic agents, such as carrageenan (CGN). This paper explains the anti-inflammatory activity of AFAL through structural comparison with anti-inflammatory legume lectins. The AFAL model was obtained by molecular modeling and molecular docking with glycan and carrageenan were performed to explain the AFAL structural behavior and biological activity. Pisum sativum lectin was the best template for molecular modeling. The AFAL structure model is folded as a ß sandwich. The model differs from template in loop regions, number of ß strands and carbohydrate-binding site. Carrageenan and glycan bind to different sites on AFAL. The ability of AFAL binding to carrageenan can be explained by absence of the sixth ß -strand (posterior ß sheets) and two ß strands in frontal region. AFAL can inhibit pathway inflammatory process by carrageenan injection by connecting to it and preventing its entry into the cell and triggers the reaction.

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Lectins are plant secondary compounds that can have anthelmintic properties in vitro. In particular, the phytohaemagglutinin lectin extracted from Phaseolus vulgaris has been shown to inhibit the feeding of Trichostrongylus colubriformis and Teladorsagia circumcincta L1 larvae. However, little is known about the potential anthelmintic properties of this lectin in vivo and its suitability to control gastrointestinal parasite infections in lambs. In a 2 × 2 study, lambs were either orally dosed, or not, with 2.3mg semi-purified PHA lectin per kg live weight (LW) per day, whilst concurrently infected, or not, with 1000 T. circumcincta and 1000 T. colubriformis L3 infective larvae per day for 42 days. There were no adverse clinical effects observed with this dose of PHA lectin. Although worm burdens were similar, animals dosed with PHA lectin had reduced concentration of nematode eggs in the faeces compared with their non-lectin dosed counterparts (P=0.026), suggesting that there may be a direct effect of PHA lectin on parasite fecundity. Irrespective of infection, PHA lectin had immune-stimulatory properties with increased eosinophillia in both abomasal and small intestine tissue sections taken at slaughter on day 42 (P<0.02 for both) and a tendency for decreased ability of Teladorsagia larvae to penetrate abomasal tissue explants (P=0.06). Compared with infection alone, concurrent PHA lectin dosing and infection further increased the number of eosinophils (P<0.01), PAS-positive (mucin-producing cells) (P=0.03) and tended to increase the number of T helper cells (P=0.06). No interactions were observed for cell populations in small intestine tissue sections. These results suggest PHA lectin could have two possible modes of action against T. circumcincta and T. colubriformis, a direct anthelmintic effect on nematode fecundity and an indirect effect through enhancing local immune responses in the host.

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A neutrophil migration-inducing protein has been isolated from the saline extract of Artocarpus integrifolia seeds by successive sugar affinity chromatography steps during which the protein was not absorbed by D-galactose resin, and then was absorbed to and eluted from D-mannose resin by 0.1 M D-mannose. Gel filtration on Superdex 75 HR indicated a molecular mass of 52 kDa when 0.1 M D-mannose was present in the elution buffer. A single band of apparent molecular mass of 13 kDa was demonstrable by SDS-PAGE only after heating, both in the presence and absence of reducing agent, suggesting that the molecule is a tetramer formed by the noncovalent association of 13 kDa chains. Isoelectric forms corresponding to isoelectric points of 4.0, 4.2, 5.0, and 5.2 were demonstrable by isoelectric focusing-PAGE, and four active forms having the same isoelectric points were separated by chromatofocusing. The minimal m.w. calculated from amino acid analysis data was 13,193. The protein, denoted KM+, stimulated neutrophil migration in the rat peritoneal cavity assay in a dose-related manner in the range of 1 to 300 micrograms per rat. The dose-response curve of the in vitro chemotactic activity of KM+ was bell shaped and its ascending limb was dose dependent in the range of 1 ng to 10 micrograms/well. D-Mannose (0.1 M) inhibited the in vitro (80%) and in vivo (60%) neutrophil migration-inducing activities of KM+ and also its hemmaglutinating activity. The chemotactic activity was shown to be caused by haptotaxis rather than chemokinesis. The physical and biologic properties of KM+ suggest that this lectin may attract neutrophils by a mechanism involving a haptotactic gradient as has been proposed for IL-8. KM+ might be used as tool to study protein-carbohydrate interactions during neutrophil migration through the extracellular matrix.

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The interaction between purified Agaricus bisporus lectin and several human proteins was studied using the Ouchterlony double diffusion and immunoelectrophoresis techniques. Only one precipitation line was observed with normal human serum, normal human colostrum, IgA1 myeloma serum, both serum monoclonal and secretory IgA1 and monoclonal IgD. No reaction was observed with monoclonal and secretory IgA2, IgG, IgM, alpha 2 macroglobulin or pregnancy-associated alpha 2 glycoprotein. These results were confirmed by hemagglutination inhibition assays when IgA1, IgA2 and IgD were tested. On the basis of this reactivity, ABL could be a useful tool for distinguishing and isolating human IgA subclasses.

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