Hydogen peroxide-dependent photocytotoxicity by phloxine B, a xanthene-type food colorant

► This is the first investigation of the significant photosensitizing effects of phloxine B (PhB) on human leukemia cell lines by the weak light. ► Our findings provide new insights into the molecular mechanisms underlying the PhB-induced apoptosis and also evaluated PhB as a promising PDT agent. ► We also revealed how the PhB-induced effects can be modulated by the H2O2-MPO-HOCl system to potentially compromise medicinal and therapeutic outcomes.