Bio-guided Isolation of Natural Iron Chelators from Mangifera indica Leaves and their Comparative Study to Desferal ®

Through bio-guided isolation, two natural iron chelators were isolated from Mangifera indica L. leaves, identified as mangiferin (1) and iriflophenone-3-C-β-D-glucoside (2). Their iron-chelating activity was compared to that of Desferal® using bipyridyl assay and EDTA as a standard. Mangiferin showed the highest activity with IC50 value of 0.385 mM (162.85 μg/mL). Furthermore, two combinations of mangiferin with Desferal® (M-D) and iriflophenone-3-C-β-D-glucoside (M-I) were evaluated. The results showed that mangiferin potentiated the iron chelation activity of Desferal® about 46%, also that M-I combination is a promising candidate formula for iron chelation therapy. In addition, mangiferin and Desferal-iron complexes were prepared and characterized by IR, UV, and Mass spectra to compare their mode of chelation to iron. Their structural stability was studied by DFT calculations. Furthermore, they displayed increased ABTS antioxidant activity when bound to iron as compared to their free form, which enhances their pharmacological importance.