Comparative study on the growth inhibition and metabolism of sodium arsenite in Euglena gracilis strains Z and SMZ

Abstract

Animals and plants differently respond to inorganic arsenite. In the present study, the authors examined the toxicity of sodium arsenite on the growth of an algae Euglena gracilis Z and its achlorophyllous mutant SMZ strains. The metabolism of sodium arsenite in Z and SMZ strains was also investigated by HPLC/ICP-MS. Comparing cell growth, Z strain was retarded under 0.25 to 0.5 mM, while the growth of SMZ retarded above lmM indicating difference of cellular response between photosynthetic strain and non-photosynthetic strain. HPLC/ICP-MS analysis identified methyl arsenic acid, dimethyl arsenic acid, and trimethylarsine oxide in both the strains suggesting similar metabolic pathway in Euglena gracilis as reported in higher organisms.