Green approach for synthesis of zinc oxide nanoparticles from Andrographis paniculata leaf extract and evaluation of their antioxidant, anti-diabetic, and anti-inflammatory activities

Bio-mediated synthesis of zinc oxide nanoparticles (ZnO NPs) was carried out by utilizing the reducing and capping potential of Andrographis paniculata leaf extract. The capped ZnO NPs were characterized using UV-Vis, XRD, FTIR, SEM, TEM and SAED analyses. FTIR analysis suggested the role of phenolic compounds, terpenoids, and proteins of A. paniculata leaf extract, in nucleation and stability of ZnO NPs. XRD pattern compared with the standard confirmed spectrum of zinc oxide particles formed in the present experiments were in the form of nanocrystals, as evidenced by the peaks at 2 theta values. SEM and TEM analysis of ZnO NPs reveals those spherical and hexagonal shapes and the sizes at the range of 96-115 and 57 +/- 0.3 nm, respectively. The synthesized nanoparticles possess strong biological activities regarding anti-oxidant, anti-diabetic, and anti-inflammatory potentials which could be utilized in various biological applications by the cosmetic, food and biomedical industries.