REVIEW ON KNOWLEDGE GAP IN Brachiaria GRASS RESEARCH AND UTILIZATION: ETHIOPIAN PERSPECTIVE

The ability of cyanobacteria and green microalgae to synthesize gold nanoparticles is well known, as is the ability to use these nanoparticles to degrade pollutants (e.g., methyl orange, methylene blue, etc.). In this paper we present our original results on the biosynthesis of gold nanoparticles in both light and dark, by the cyanobacterium Synechocystis PCC 6803, green microalga Chlorella sorokiniana UTEX 1230, as well as our two green microalgae strains temporarily named Ra and Rd. In this way we try to find out the contribution of photosynthesis to the synthesis of nanoparticles, as well as the contribution of aerobic respiration to this process. Up to our best knowledge this is the first report concerning the possibility to influence the intracellular position of nanoparticles by varying the conditions of NP synthesis, namely in our experiments the darkness coupled with anaerobiosis. The synthesized nanoparticles were inspected by TEM, both in situ (on ultra-thin sections) and after extraction. The collected gold nanoparticles were further used as catalysts for the degradation of methylene blue.