Antibacterial and toxicity activities of green synthesized silver nanoparticles from phyllanthus amarus extract / Siti Sara Nor Azhar

Silver nanoparticles (AgNPs) were synthesized through an easy, rapid and eco-friendly pathway using various herb plant because of the huge values in medical bioengineering. Therefore, the aims of this study were to identify the formation of silver nanoparticles from Phyllanthus amarus extract, characterize it using UV-Visible spectrometer, identify the antibacterial and toxicity activities of bio-synthesized AgNPs. P. amarus was extracted and added with 1 mM of silver nitrate (AgNO3) for 15-20 min. Then, the AgNPs synthesized from P. amarus extract was further characterized using UV-Visible spectrometer. The AgNPs then was tested on their antibacterial activity using disc diffusion method and toxicity activities using brine shrimp lethality assay. The result from this study, the synthesized AgNPs was noticed through the color changes from light yellow to dark brown indicated the formation of AgNPs and further confirmed by surface plasmonic resonance (SPR) band in the range of 400-450 nm using UV–Visible spectrometer. In antibacterial activity, Pseudomonas aeruginosa showed more sensitive result compared to the Bacillus subtillis towards AgNPs of P. amarus with highest zone inhibition of 11±0.57 mm at 1000 μg/ml and Bacillus sp with zone inhibition of 10±0.57 mm at 1000 μg/ml. Besides, in toxicity activity P. amarus extract and AgNPs was characterized as non-toxic class of LC50 with 7979.98 and 2225.61 while the AgNO3 showed toxic class with LC50 of 995.68. In conclusion, P. amarus extract can be used efficiently as reducing and capping agent in the production of potential antibacterial and non-toxicity of AgNPs for commercial application.