Effect of inorganic salts on the growth and Cd2+ bioaccumulation of Zygosaccharomyces rouxii cultured under Cd2+ stress

Abstract

Using living cells to remove heavy metals was limited by the sensitivity of living cells to heavy metal ions. Effect of inorganic salts on the growth and Cd(2+) bioaccumulation of Zygosaccharomyces rouxii (Z. rouxii) was studied. Results showed that NaCl, KCl, CaCl(2) and MgCl(2) could markedly reduce the growth inhibition ratio while NaNO(3), KNO(3), Na(2)SO(4) and K(2)SO(4) significantly increased it. Effect of inorganic salts on the Cd(2+) bioaccumulation of Z. rouxii indicated that different inorganic salts could promote or restrain the growth of Z. rouxii under Cd(2+) stress by weakening or enhancing Cd(2+) bioaccumulation. Although NaCl and KCl lowered the Cd(2+) accumulation per unit weight of Z. rouxii biomass, the total Cd(2+) bioaccumulation and Cd(2+) percentage removal both markedly increased. It suggested that NaCl and KCl could be introduced to enhance the growth and Cd(2+) bioaccumulation of Z. rouxii under Cd(2+) stress.