Astragalus sarcocolla Gum-mediated a Novel Green-synthesis of Biologically Active Silver-Nanoparticles with Effective Anticancer and Antimicrobial activities.

Cancer diseases and microbial infections are the subject of several ongoing recent researches. In this paper, aqueous extract of red and yellow Astragalus sarcocolla gum was used as safe and green agent, for the synthesis of novel biologically active silver-nanoparticles. Six silver nanoparticles (AgNPs) with different characters were obtained using sarcocolla gum at (5, 10 and 20 mg/ml (w/v)) concentrations. All biosynthesized AgNPs were characterized using UV–visible spectroscopy, Transmission Electron Microscopy (TEM), and Dynamic light scattering (DLS). Cytotoxic effect of sarcocolla gum-AgNPs against five human cancer cells and one normal cells was determined using the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5- diphenyltetrazolium bromide) assay. The semi rounded particles formed from 5mg/ml red gum (AgNPs-RG1) and having 9.23±3.66 nm size range were the most active and possessed high cytotoxic effect against, A549 lung, pc3 prostate, Mcf-7 breast and paca2 pancreatic cancers, with IC₅₀ values (88.4,75.6, 72.2& 55.0 ug/ml, respectively), but showed low cytotoxic effect (20 % at 100ug/ml) against human normal cells (BJ-1). On the other hand, the spherical to cubic shaped nanoparticles obtained from 5mg/ml yellow gum (AgNPs-YG1) with 10.92 ± 5.48 nm size range, showed good cytotoxic effect against three cancer cells (PC3 prostate, MCF-7 breast and paca2 pancreatic) with IC₅₀ values (75.0, 82.8 and 81,6ug/ml respectively), and normal cells(BJ-1) with IC₅₀ value (81.8ug/ml). Antibacterial and antifungal activities of the synthesized red and yellow gum-mediated AgNPs with different sizes and shapes were also investigated. Particles biosynthesized from 5 and 10 mg/ml red gum (AgNPs-RG1, RG2) and 5mg/ml yellow gum (AgNPs-YG1) exhibited broad spectrum antimicrobial effects against all tested pathogenic gram-positive, gram-negative bacterial strains, unicellular yeast and filamentous fungi. Based on these results, it can be concluded that the synthesized silver nanoparticles from low concentrations of sarcocolla gum have significant biomedical applications. [ABSTRACT FROM AUTHOR]