Theoretical and Experimental in vivo Study of Antioxidant Activity of Crocin in Order to Propose Novel Derivatives with Higher Antioxidant Activity and Their Delivery via Nanotubes and Nanocones.

In this study, the antioxidant activity of crocin via experimental and theoretical methods was investigated. In order to induce oxidative stress, 30-min renal ischemia and 24-h reperfusion were used in male Wistar rats. Oxidative stress was assessed by measuring tissue malondialdehyde (MDA) and ferric reducing/antioxidant power (FRAP). The results showed that following ischemia/reperfusion, the level of MDA was increased and FRAP decreased. Both of these changes were alleviated by crocin administration. The bond dissociation enthalpy and ionization potential values as enthalpies of mechanism of antioxidant activity of crocin were calculated by density functional theory method. According to obtained results, the novel structures of crocin with higher antioxidant activity for synthesis were proposed. Results indicated that NH2, OMe, and F substituents can improve the antioxidant activity of crocin. The crocin delivery via carbon and boron nitride nanotubes and nanocones was investigated. The results confirm that the calculated adsorption and free Gibbs energies of crocin on the surface of studied nanostructures were negative meaningfully, so these processes were exothermic and experimentally possible from the energetic viewpoint.