Resumen:
Research in cactus (Opuntia ficus-indica (L.) Mill.) cladodes as a functional food increases because of their (poly)phenolic
compounds and health-promoting ability. Extraction conditions are the basis to obtain the highest amount of bioactive compounds with antioxidant properties. Therefore, several individual and combination of extraction solvents and conditions were
carried out. Even a great amount of (poly)phenols was extracted using 80% ethanol; the combination of solvents with different
polarities (methanol, acetone and water) favored the extraction of flavonoids and antioxidant capacity (DPPH and ABTS
radicals). The extract with the highest flavonoid content was that obtained by successive extractions. Additionally, in order to
quantify (poly)phenols by HPLC-DAD, aglycones were released from glycosides by acid hydrolysis (0.6, 1.2, 1.5, and 1.7 M
HCl) through reflux at 90 °C at different times (2 h and 3 h). Flavonoid aglycones (isorhamnetin, quercetin, and kaempferol) and
phenolic acids (ferulic and 4-hydroxybenzoic acids) were identified and quantified. Acid hydrolysis with 1.5 M HCl during 2 h
was the best for the release of flavonoid aglycones, without phenolic acid degradation. Likewise, less acidity (0.6 M HCl) does
not completely release the aglycones whereas a higher acidity (1.7 M) and a longer time of reflux (3 h) resulted in the degradation
of flavonoid aglycones.
