Microbial Green synthesis of nanoparticles has a potential to develop simple, environmentally acceptable solvent systems, cost effective methods for production of great technologically important materials. In this study, Crystallized silver nanoparticles (SNPs) have been biosynthesized by Spirulina platensis as powder algal biomass with extracellular bio-synthesis of AgNPs from AgNO3 solution being reported. Silver nanoparticles synthesis was confirmed by UV-Visible Spectroscopy, electron microscopes (TEM) , Fourier transmittance infrared spectroscopy FTIR and Zeta potential measurement. Synthesized silver nanoparticles algal extracts were screened against bacterial and fungal pathogens. Antioxidant activity using DPPH free radical scavenging assay was determined. Standard antibiotic discs were conjugated with the algal silver extracts for comparison. where decreasing order of antibacterial activity (zone of inhibition in mm) for antibiotics with AgNPs conjugates against bacterial group was noted as follows: imipenem + AgNPs >Cefotaxime + AgNPs > Clindamycin + AgNPs. Both, antimicrobial and antioxidant activity of AgNPs extracts showed a considerable activity, giving as such a promising approach in the pharmaceutical industry.
