Determination of bioremediation properties of soil-borne Bacillus sp. 5O5Y11 and its effect on the development of Zea mays in the presence of copper

Today, industrial activities lead to the accumulation of heavy metals in the soil, water, and air due to mine deposits and operations, fertilizers, and drugs used in agriculture, and urban wastes. Using microorganism bioremediation of metals is an important technique in solving these problems. Herein, a rhizoid bacterium isolated from orchids that grow in Ovit plateau was defined as Bacillus sp. 5O5Y11 by conventional and molecular methods and the bioremediation properties of strain were investigated. It was capable of growth at high salt (10-15%) concentration, wide temperature (10-45 °C) and pH range (pH 4.5-8.0), and was observed to have strong lecithinase, gelatinase activity, and nitrate reduction. When the plant growth-promoting properties of this strain were examined, strong siderophore and ammonium production were observed in in vitro conditions. Bacillus sp. 5O5Y11 was found to have high tolerance to a group of heavy metals [iron (Fe), copper (Cu), lead (Pb), silver (Ag), zinc (Zn)]. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) values of copper metal on Bacillus sp. 5O5Y11 were determined as 12.5 mM and 50 mM, respectively. The effectiveness of this bacterium on the germination and growth of maize plant in the presence and absence of copper were investigated. These results suggest that Bacillus sp. 5O5Y11 is a microorganism, which has potential in metal bioremediation and plant growth promotion.

Keywords: Bacillus; Bioremediation; Copper resistance; Heavy metal; Zea mays.