Análisis de la actividad antioxidante y actividad hemaglutinante en extractos de hojas de plantas medicinales

Abstract

Reactive oxygen species (ROS) produced in aerobic organisms by internal and external agents causes damage such as lipid peroxidation and DNA damage, these negative effects can be offset by the effect of antioxidant mechanisms due to its ability to capture free radicals. Plants have natural antioxidants and lectins, these lectins are proteins that recognize carbohydrates specifically and reversibly. ROS present in the media and/or in cells can modify the lectin activity and effect on cells. Therefore the objective of the present thesis was to analyze the antioxidant and hemagglutinating activity in four medicinal plants commonly used in Mexican traditional medicine. These plants were: watercress (Nasturtium officinale), capitaneja (Verbesina crocata), epazote (Dysphania ambrosoides) and leaves of the little hand flower tree (Chiranthodendron pentadactylon). Results: Chromatographic analysis revealed that acetonic pigments contain chlorophylls and carotenoids in all plants. Meanwhile the alcoholic pigments contained high concentration of phenols, polyphenols and flavonols, the highest content was found in the leaves extracts of the little hand tree. And also this plant has the highest concentration of polyphenols (121 mg/g) and flavonoids (94 mg/g). Regarding the antioxidant activity all alcoholic pigments present this activity, the highest antioxidant activity was found in the alcoholics pigments of watercress leaves (Nasturtium officinale). Finally all plant studied have lectins with different carbohydrate specificity due to the presence of a mixture of lectins with affinities for GalNAc, Gal and Fuc. This work constitutes the first international report where antioxidant and hemagglutination activity was demonstrated in four plants commonly used in Mexico.

Las especies reactivas de oxigeno (ROS), producidas en los organismos aerobios, por agentes tanto externos como internos causan daños como la peroxidación lípidica y daños al ADN, estos efectos perniciosos pueden ser contrarrestados por el efecto de mecanismos antioxidante debidos a su capacidad de capturar radicales libres. Las plantas poseen antioxidantes naturales y lectinas que son proteínas que pueden reconocer de manera específica y reversible a diferentes carbohidratos; estas lectinas pueden variar su actividad y su estructura dependiendo de la cantidad de ROS presente en su medio en las células. Por lo anterior el objetivo de la presente tesis fue el análisis de la actividad antioxidante y actividad hemaglutinante en plantas medicinales ampliamente utilizadas en la medicina tradicional mexicana, estas plantas fueron: berro (Nasturtium officinale), capitaneja (Verbesina crocata), epazote (Dysphania ambrosoides) y flor de manita (Chiranthodendron pentadactylon).