Characterization of copper biosorption and bioreduction by copper resistant bacteria isolated from a vineyard soil

摘要

This study presents factors affecting copper bioreduction and biosorption by a highly copper resistant monoculture of Pseudomonas putida strain NA and copper bioremoval from soil. Seven bacteria resistant to high concentration of Cu(II) were isolatedfrom enrichment cultures of vineyard soils and mining wastes. Culture parameters influencing copper bioreduction and biosorption by one monoculture isolate were studied. The isolate was identified by 16S rRNA gene sequence analysis as a Pseudomonas putida strain NA (98% similarity). The optimal temperature for growth was 30degC and bioremoval (bioreduction and biosorption) of Cu(II) was maximal at 35degC. Considerable growth of the isolate was observed between pH 5.0 and 8.0 with the highest growth andbiosorption recorded at pH 6.0. Maximal bioreduction was observed at pH 5.0. Pseudomonas putida strain NA removed more than 110 mg/L Cu(II) in water within 24 h through bioreduction and biosorption. More than 23 mg/L of Cu(JJ) was biologically reduced in24h at an initial concentration of 100 mg/L. In 12 h, 20 mg/L of Cu(II) was removed through biosorption. Results indicate a great potential for use of Pseudomonas putida NA for bioremoval of copper from water and soil.