A plausible chemical mechanism of the bioactivities of mangiferin.
Shibnath Ghosal, Gangadhara Rao, Saravanan V., Nira Misra, Dipak Rana
Author Affiliation: Department of Pharmaceutics, Banaras Hindu University, Varanasi 221 005, India.
Indian Journal of Chemistry. Section B, Organic including Medicinal 35 : 561-566
Abstract : A possible chemical mechanism for the observed bioactivities of mangiferin, a naturally occurring C-glucosylxanthone, extracted from Mangifera indica bark, is described. The mechanism focused on its capacity to provide cellular protection as an antioxidant and a radical scavenging agent. Mangiferin performs its antioxidant function at different levels of the oxidation sequence. As far as membrane lipid peroxidation and consequent immunomodulations are concerned, it acts by (i) decreasing localized O2 concentration thereby generating mangiferin phenoxy radicals; (ii) binding metal ions (Fe2+/3+) in forms that will not allow the generation of tissue-damaging species such as hydroxyl and highly reactive oxo-ferryl radicals; (iii) regulating polymer chain lengthening (membrane lipids) by interacting with the reactive oxygen species; (iv) scavenging intermediate radicals (such as lipid peroxy and alkoxy radicals) to prevent continued H abstraction from cellular lipid molecules; and (v) maintaining cellular oxidant-antioxidant balance. Chemical evidence in support of the above postulate was sought and obtained in the form of a complex polymer.