Fig. 4From: Biosynthesis, characterization, and in vitro assessment on cytotoxicity of actinomycete-synthesized silver nanoparticles on Allium cepa root tip cellsChange in color of Streptomyces sp. NS-33 supernatant after mixing and incubation with AgNO3. (a) Streptomyces sp. NS-33 supernatant (pale yellow). (b) The formation of AgNP suspension (brown)Back to article page