Evaluation of the antioxidant capacity and content of polyphenols obtained from tea (Camellia sinensis) of four brands sold in Colombia by extraction at room temperature

Herbal medicines have long been used to treat chronic diseases such as cancer, neurodegeneration and diabetes, usually in the form of herbal teas, also called tisanes. Tea, second only to water, is the most highly consumed beverage worldwide and its medicinal and health properties, long known to early Chinese civilizations, have been widely explored. The consumption of green tea in Colombia is a recent trend and the market is continuously growing, then the most common commercially available types of green tea were tested in this study; Oriental, Lipton, Hindú and Jaibel. The main objective of this study was to determine and compare the amount of polyphe-nols present in tea samples considering extraction in water at room temperature and stirring every 30 seconds for 5 minutes. The antioxidant capacity was determined by the 1,1- diphenyl-2-picrylhydrazyl (DPPH) free-radical scav-enging assay and the oxygen radical absorbance capacity (ORAC) assay. Concentrations ranging from 22.36 ± 0.98 to 41.29 ± 0.86 mg Trolox equivalent / g dry sample for DPPH assay and 22.95 ± 1.31 to 46.25 ± 2.05 mg Trolox equiv-alent / g dry simple were determined for ORAC assay. It was also found that the amount of total phenols in tea samples ranging from 2.53 ± 0.25 to 14.63 ± 0.53 mg gallic acid equivalent (GAE) / g dry sample and total flavonoid content concentration was obtained from 2.67 ± 0.20 to 7.08 ± 0.38 mg catechin equivalent / g dry simple. The antioxidant activity and total flavonoid content were highly correlated for both DPPH (r2= 0.9911) as ORAC (r2 = 0.9968). Tea extracts from the Oriental brand had the highest polyphenol content showing greater biological ac-tivity, contrary to Jaibel tea brand which recorded the lowest concentrations in all analyzes

I Congreso - Convergencias y divergencias. Hacia educaciones y desarrollo otros.

La presente colección, en su primera publicación, recoge la experiencia del I Congreso Internacional de Educación para el Desarrollo en Perspectiva Latinoamericana- EpDl “Convergencias y divergencias. Hacia educaciones y desarrollos otros.” organizado por el Centro de Educación para el Desarrollo-CED de UNIMINUTO, específicamente en relación con las ponencias, libros e iniciativas fotográficas presentadas en las seis líneas temáticas de este evento académico, a saber: (a) experiencias y prácticas pedagógicas; (b) acciones colectivas, movimientos y redes sociales; (c) perspectivas críticas al desarrollo; (d) producción de conocimiento; (e) diferencias, identidades y ciudadanía; (f) cuerpos, emociones y espiritualidades; a partir de éstas propuestas y en el marco de estas líneas, se reflexionó sobre las dinámicas y problemáticas derivadas del desarrollo hegemónico, así como sobre la posibilidad de diálogo entre saberes y conocimientos construidos de forma contextualizada, que permitan agenciar apuestas y proyectos alternativos disidentes en la búsqueda de “desarrollos y educaciones otras” desde América Latina