Phytoconstituents, Antioxidant Activity and Cytotoxicity of Puya chilensis Mol. Extracts in Colon Cell Lines

<i>Puya chilensis</i> Mol. is a plant of the Bromeliaceae family, which has been traditionally used for medicinal applications in various digestive disorders. In this study, the phytoconstituents of six extracts of stems and flowers of <i>P. chilensis</i> were evaluated: phenols, flavonoids and total anthraquinones, as well as their antioxidant capacity and cytotoxicity in colon cancer cell lines HT-29. The data demonstrate that the ethyl acetate extract of <i>P. chilensis</i> flowers is cytotoxic in HT-29 cell lines (IC₅₀ = 41.70 µg/mL) without causing toxic effects on healthy colon cells (IC₅₀ > 100 µg/mL); also, this extract concentrated the highest amount of phenols (4.63 μg GAE/g d.e.), flavonoids (31.5 μg QE/g d.e.) and anthraquinones (12.60 μg EE/g d.e.) among all the extracts tested, which also correlated with its highlighted antioxidant capacity (DPPH∙IC₅₀ = 4.15 mg/mL and FRAP 26.52 mM TEAC) over the other extracts. About thirty-five compounds were identified in this extract-the fatty acid esters present have been shown to have therapeutic effects on several types of cancer and could explain its antiproliferative activity.