Sunil Pandey, Goldie Oza, Arvind Gupta, Ritu Shah, Madhuri Sharon
The green nanotechnological approach for the biosynthesis of gold nanoparticles by exploiting the reducing and thermodynamically efficient molecular mechanisms of medicinal plant Asparagus racemosus is reported in the present work. The most influential parameter was found to be temperature. At lower temperature (30ºC) the other optimum parameters were pH 8 and 100 ppm of aurochlorate salt; whereas at higher temperature (100ºC) the optimum parameters were pH 6 , 100 ppm of aurochlorate salt. The involvement of Glutathione as one of the capping proteins and nitrate reductases as possible reducing agent was confirmed by FTIR and biochemical assays respectively. The nitrate reductase activity was found to be reduced from 0.8293 mmole/min/gram to 0.6654 mmole/min/gram after bio fabrication of gold nanoparticles. Similarly, capping protein assay of Asparagus racemosus showed that total protein concentration in leaf extract was 17.14 μg/ml and its concentration was reduced after biofabrication of GNPs. The morphology and the crystal structure of the gold nanoparticles (GNP) were studied using electron microscopy and XRD respectively.