In summary, the bio-reduction of aqueous silver ions to silver nanoparticles using S. varians has been demonstrated. The
procedure applied is simple, economic and ecofriendly. Thesecharacteristics are marvelous, through sustainable development of nanomaterial production. Besides that, smaller size, size uniformity and appropriate dispersion of the nanoparticles were other important aspects of this study. Investigation on the antibacterial effect of nanosized silver against pathogenic bacteria reveals high efficiency of silver nanoparticles as a strong antibacterial agent. This green and sustainable technology
toward the synthesis of nanoparticles can be developed for the large-scale production of other nanomaterials.