Protective Effect of Bioavailable Phycocyanin Against Oxida-tive Damage in ABO System Erythrocytes Caused by 2,4-Dichlorophenoxyacetic Acid and Imidacloprid

In this study, the cytotoxicity of the pesticides 2,4-dichlorophenoxyacetic acid (2,4-D) and imidacloprid was evaluated on erythrocytes from different ABO blood groups, through the assessment of partial hemoglobin release. The results showed significant differences in susceptibility to oxidative damage according to blood type: for 2,4-D, the sensitivity order was A+ > B+ > O+, whereas for imidacloprid it was B+ > A+ > O+. Furthermore, the erythroprotective effect of C-phycocyanin was determined, showing up to 89% inhibition of hemolysis at 1 mg/mL, with significant variations among blood groups. To simulate physiological conditions, an in vitro digestion was performed to obtain bioavailable fractions of both pesticides and C-phycocyanin. After digestion, pesticides retained their ability to induce damage, while C-phycocyanin maintained its protective effect, although reduced, reaching a maximum of 24% inhibition. At the computational level, molecular docking was carried out with AutoDock Vina between the beta subunit of C-phycocyanin and 2,4-D, reporting a binding energy value of –4 to –5 kcal/mol across nine interaction sites, mainly favored by ionic interactions and hydrogen bonds. These findings suggest that the protective mechanism of C-phycocyanin is mainly associated with its antioxidant scavenging capacity.