GREEN SYNTHESIS OF SILVER NANOPARTICLES FROM BIOACTIVE EXTRACT MANGROVE PLANT AND ITS FREE RADICAL SCAVENGING ACTIVITY

摘要

In one of the aspect of the invention it is provided that a method for green synthesis of silver nanoparticles from the active extract obtained from mangrove plant, the mangrove plant is selected from species Derris trifoliata and Sonneratia alba, the stem of the mangrove plant is cleaned dried at 40-50 °C cut down into pieces and finally grinded to fine powder; The fine powder is soaked in water for about 10 minutes, further boiled for 10 minutes filtered and 5 % of the extract is further used as bio-reductant; The silver nanoparticles are prepared by the reaction of the standard silver salt solution and aqueous bio-reducing solution extracted from the mangrove plant, the reaction progress is monitored by analytical techniques and further nanoparticles obtained characterized by the XRD, TEM. In an another aspect of the invention the nanoparticles obtained further applied for antioxidant activity of the free radicals , the free radical scavenging capacity further determined by the DPPH (200uM) negative control. Different concentrations of Ag NPs (25-100μg/ml) in water were prepared. Ascorbic acid was used as positive control. Reaction mixture was prepared and incubated for half an hour at R.T. Absorbance was measured at 517nm. Change in absorbance with respect to control is calculated as % scavenging activity.