Alcohol–alkaline extracted date pit residue exhibits antioxidant protective effects against azoxymethane-induced oxidative stress in the rat colon

Date pits are a major agricultural by-product rich in bioactive compounds with potential health-promoting properties. This study aimed to characterize the antioxidant properties of three date pit-derived residues [alcohol-extracted residue (AER), alkaline-digested residue (ADR), and alcohol-alkaline-extracted residue (AAER)], and to evaluate their effects on the viability of a selected human cultured cell line. Initial in vitro screening using the DPPH radical scavenging assay and a Caco-2 colon adenocarcinoma cell viability model showed that AAER exhibited the strongest bioactivity compared with AER and ADR. Accordingly, AAER was selected for further in vivo evaluation using an azoxymethane (AOM)-induced rat model of colonic oxidative stress. Supplementation with AAER significantly alleviated the adverse effects of AOM exposure. In particular, AAER restored intracellular glutathione levels and total antioxidant capacity, enhanced the activities of key antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, and superoxide dismutase), and reduced oxidative DNA damage. Collectively, these findings indicate that AAER possesses substantial antioxidant activity and might have potential as a natural bioactive ingredient for use in functional foods or dietary supplement applications.