A Study of the Fruits of Catalpa bignonioides Walt.: Evaluation of the Antioxidant, Anti-Inflammatory, and Anti-Cancer Activities in Colorectal Adenocarcinoma Cells in Relation to Phytochemical Profile

Abstract

The chemical profiles and potential anti-inflammatory, antioxidant, and anticancer activities of the aqueous extract and fractions of fresh Catalpa bignonioides fruits were studied. Iridoids, flavonoids, and phenolic compounds represent the main phytochemical classes. Nine of the ten iridoids detected are acyl-iridoids. Significant amounts of catalpol and catalposide were found. The antioxidant activity of iridoids was demonstrated by HPTLC analysis coupled with a DPPH derivatization and by applying four in vitro tests, such as DPPH, ABTS, FRAP, and the β-carotene bleaching test. C. bignonioides extract and fractions were also evaluated for their anti-cancer activity using in vitro models of colorectal cancer (HT29 and HCT166 cell lines), and focusing on the effect of the different fractions on inflammation and oxidative stress, key factors that drive the onset and progression of colon cancer.