*2.1. Materials*

Sodium carbonate (lot a0594092339), anhydrous sodium acetate (lot 882032), absolute ethanol (lot k4958171742), potassium persulphate (lot k40707991048), methanol (lot l823009611), acetic acid glacial (lot k47109963539), acetone (lot k43912814243), sodium hydroxide (lot b0895598319), concentrated hydrochloric acid (lot k41017317016), Folin–Ciocalteu phenol reagen<sup>t</sup> (lot hc43368401), Mueller–Hinton broth (lot b1223098542), tetrahydrofuran (lot dg643), and

2,4,6-tri-(2-pyridyl)-1,3,5-triazine (lot l58155738107) were obtained from Merck (Darmstadt, Germany). Dimethyl sulfoxide (lot 190260) was obtained from PanReac AppliChem (Barcelona, Spain). 2,2-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), 2, 2-diphenyl-1-picrylhydrazil (067k lot 1154), and diammonium salt (lot slbp9592v) were obtained from Sigma-Aldrich (St. Louis, MO, USA). (±)-6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) (97% lot stbb6668) was obtained from Aldrich Chem (St. Louis, MO, USA). Ferric chloride. 6H2O (lot 9n005099n) was obtained from Carlo Erba (Barcelona, Spain). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) (lot p31b064) was obtained from Alfa Aesar (Haverhill, MA, USA). Annatto seeds were purchased from a farmers market of Medellín city (Colombia), which were sun-dried until reaching a moisture content of 10.58 ± 0.98%.
