ABSTRACT
Resumen: El gel de Aloe vera es considerado una fuente natural de múltiples beneficios, originados por la acción combinada de vitaminas, aminoácidos, compuestos fenólicos, enzimas, minerales, ácidos orgánicos, lípidos y carbohidratos, que se relacionan con la mejora de enfermedades neuro-degenerativas como Alzheimer. Los ensayos in vitro e in silico permiten confirmar e identificar posibles beneficios de esta planta y sus compuestos en enfermedades. El objetivo del presente trabajo fue evaluar la actividad antioxidante del gel de A. vera y mediante análisis in silico, establecer el potencial terapéutico de sus compuestos bioactivos en la enfermedad de Alzheimer. Se obtuvieron hojas de A. vera, de las que se extrajo el gel, retirando el exocarpio, se liofilizó y almacenó hasta su uso. Se caracterizó la capacidad antioxidante, se cuantificaron los compuestos fenólicos y flavonoides y se analizó la relación que existe entre los parámetros mediante correlación de Pearson. Mediante análisis in silico se evaluó el potencial de interacción de 8 compuestos del gel con la proteína gamma secretasa. El gel de A. vera obtuvo alta capacidad antioxidante por ABTS, DPPH, radical OH y poder reductor, usando bajas concentraciones para inhibir el 50 % de los radicales, y correlaciones positivas con fenoles totales y flavonoides. En el estudio in silico el compuesto que presentó mejor unión con gamma secretasa fue aloe-emodina, con menor energía libre de unión y menor concentración de constante de inhibición, sugiriendo su potencial uso como coadyuvante en el tratamiento de la enfermedad de Alzheimer.
Abstract: Aloe vera gel is considered a natural source of multiple benefits, originated by the combined action of vitamins, amino acids, phenolic compounds, enzymes, minerals, organic acids, lipids and carbohydrates, which are related to the improvement of neuro-degenerative diseases such as Alzheimer's. In vitro and in silico tests allow us to confirm and identify possible benefits of this plant and its compounds in diseases. The objective of the present study was to evaluate the antioxidant activity of A. vera gel and, through in silico analysis, to establish the therapeutic potential of its bioactive compounds in Alzheimer's disease. A. vera leaves were obtained, from which the gel was extracted, removing the exocarp, lyophilized and stored until use. The antioxidant capacity was characterized, the phenolic compounds and flavonoids were quantified, and the relationship between the parameters was analyzed using Pearson correlation. The interaction potential of 8 compounds in the gel with the gamma secretase protein was evaluated through in silico analysis. The A. vera gel obtained high antioxidant capacity due to ABTS, DPPH, OH radical and reducing power, using low concentrations to inhibit 50 % of the radicals, and positive correlations with total phenols and flavonoids. In the in silico study, the compound that showed the best binding with gamma secretase was aloe-emodin, with lower binding free energy and lower inhibition constant concentration, suggesting its potential use as an adjuvant in the treatment of Alzheimer's disease.
ABSTRACT
Soluble or fermentable fibre has prebiotic effects that can be used in the food industry to modify the composition of microbiota species to benefit human health. Prebiotics mostly target Bifidobacterium and Lactobacillus strains, among others, which can fight against chronic diseases since colonic fermentation produces short chain fatty acids (SCFAs). The present work studied the changes produced in the fibre and polyphenolic compounds during in vitro digestion of gel (AV) and a polysaccharide extract (AP) from Aloe vera, after which, these fractions were subjected to in vitro colonic fermentation to evaluate the changes in antioxidant capacity and SCFAs production during the fermentation. The results showed that the phenolic compounds increased during digestion, but were reduced in fermentation, as a consequence, the antioxidant activity increased significantly in AV and AP after the digestion. On the other hand, during in vitro colon fermentation, the unfermented fibre of AV and AP responded as lactulose and the total volume of gas produced, which indicates the possible use of Aloe vera and polysaccharide extract as prebiotics.