In vitro and in vivo anti-inflammatory activity of green synthesized silver nanoparticles from the aqueous bark extract of Mangifera indica Linn. (Anacardiaceae)

Abstract

The increasing demand to produce secure and cost-effective healthcare nanodevices is at the forefront of research in nanotechnology. The present work reports a simple and eco-friendly synthetic method for silver nanoparticles using the bark aqueous extract of Mangifera indica (MI-AgNPs) for the management of inflammation. MI-AgNPs were obtained following incubation of the mixture of the plant extract with silver nitrate solution (10:50 v/v). The sample was biophysically characterized using Ultraviolet Visible spectroscopy (UV-Vis), Fourier Transform Infrared spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD) and Dynamic Light Scattering (DLS) technics while egg albumin denaturation and carrageenan-induced rat paw edema model were used to evaluate its anti-inflammatory activity. The changing colour of the reaction mixture and UV-Vis absorbance spectrum validated the formation of MI-AgNPs, showing a characteristic peak at 410 nm. FTIR spectra showed the main reducing groups from the bark extract and PXRD highlighted the crystalline nature of the MI-AgNPs. The hydrodynamic diameter was found to be 104 nm with a polydispersity index of 0.27. Anti-inflammatory activity of MI-AgNPs was observed in a dose-dependent manner. In heat-induced egg albumin denaturation method, MI-AgNPs exerted maximum protection of 80 % at 200 g/mL (highest tested concentration) while aspirin used as reference drug exhibited 67 % protection. Similarly, the oral pre-treatment of rats with MI-AgNPs caused significant (P<0.001) inhibition of carrageenan-induced rat paw edema with a maximum inhibition of 89 % at the dose of 200 g/kg. These findings infer that Mangifera indica bark aqueous extractmediated silver nanoparticles could be considered as an interesting solution for the development of therapeutic strategies against inflammation related diseases.