Evaluation of the Antioxidant Activity and Effects of Phenolic Compounds Found in Beetroot Leaves on Colorectal Cancer Cells

Beetroot (Beta vulgaris L.) leaves, often discarded despite their nutritional value, are rich in bioactive phenolic compounds with potential anticancer properties. This study evaluated the antioxidant activity and effects of digested beet leaves on HCT116 colorectal cancer cells. After in vitro digestion, the leaves exhibited significant antioxidant activity (ORAC, ABTS, DPPH) and preserved DNA integrity in the presence of oxidizing agents. Treatment with the digested material significantly reduced cancer cell proliferation, colony number, and size. Additionally, it inhibited phosphorylation of key proteins (S6, S6K1, S6K2) in the mTOR pathway. Isolated apigenin, while not affecting colony number, decreased colony size. These findings suggest that beet leaves retain bioactive properties after digestion and may offer anticancer benefits against colorectal cancer.