ocimum gratissimum: phytochemical analysis and green synthesis of ag/ag2o nanoparticles

Biosynthesis of ag/ag2o nanostructures was performed using a cheap and environmentally friendly method, where silver ions in agno3 were reduced via co-precipitation using bio-reductants present in the aqueous extract of ocimum gratissimum leaf [1]. in addition, the amount of phytophenols, total phenol, flavonoid content, anthocyanin, and flavone and flavonol content as well as no and dpph assay before and after nanoparticle synthesis were measured to obtain the amounts of active reductants or capping agents in the plant. the measured predominant phenolic compounds in this extract were sinapic acid and gallic acid. moreover, the amount of total phenol content, total flavonoid content, flavone, and flavonol content, and total anthocyanin, were 113.8 μg eq gallic acid mg-1 extract, 10.3 μg eq gallic acid mg-1 extract, 0.01 μg eq gallic acid mg-1 dw and 7.4 mmol l-1, respectively. the amount of ic50 in the extract, before and after synthesis of ag/ag2onps, were 387.1 and 99.9 μg ml-1, respectively, compared to the standard ascorbic acid [2]. the percentages of inhibition no before and after the synthesis of ag/ag2onps were 19.3% and 48.7%, respectively which implies that nanoparticle synthesis increases antioxidant activity in contrast to o. gratissimum extract. scanning electron microscopy (sem) of ag/ag2onps showed the average particle size was 11.49 nm. the formation of nanoparticles was successfully confirmed using uv-vis absorption spectroscopy and different properties of the resulting nanoparticles were determined using x-ray diffraction (xrd) and field emission scanning electron microscopy (fe-sem) [3]. naked observations also imply a color change of extract from light brown to dark brown that proves silver nanoparticle synthesis.