Removal of Cu2+ and Pb2+ ions from aqueous solutions by free, immobilized and co- immobilized cells of Saccharomyces cerevisiae and Lactobacillus sporogenes

Abstract

Water is one of the foremost elements for all living forms of life .The hot spot, Water pollution is of great concern to scientists as water is a prime necessity of life. Heavy metals are one of the major classes of pollutants in marine, lake and in ground waters. Since conventional treatment technologies are not economical and effective, we have adapted eco friendly technology known as – Biosorption. It has been proved to be more successful in binding heavy metals by using various micro organisms. The immobilization of the cells on a suitable support simplify the treatment of liquid waste as the entrapment of living cells increases the retention time of cells in contaminated water. In the present study, the free and immobilized cells of Saccharomyces cerevisiae and Lactobacillus sporogenes were used as biosorbent materials for the removal of heavy metals (Cu⁺² and Pb⁺² ions) from the aqueous solution. The major factors such as pH, incubation time, initial concentration of biomass and temperature were verified to optimize the process. The selected micro organisms exhibited maximum removal at an optimum concentration of 1mg/mL, optimal time of 180min, optimum temperature of 35⁰C and pH 4-6. The various influencing factors for sorption of Cu⁺² and Pb⁺²ions have been discussed.

Keywords:  Saccharomyces cerevisiae, Lactobacillus sporogenes, heavy metal pollution and Biosorption.