Identification of a lead-resistant mildew strain and the test on its ability of adsorbing lead ion

摘要

Selective liquid media with a serial of Pb2+ concentrations were used for screening lead-resistance microorganisms from sewage and industrial waste water, and one microbe strain lyh3A with strong Pb2+-resistance was gained. With Pb2+ concentration in medium increasing, it was tested the maximum tolerance to Pb2+ concentration of lyh3A was 1.5 g/L. This strain was identified as Aspergillus niger through conventional microscope observation and 18S rDNA sequence analysis. The optimal combination of some factors for lyh3A adsorbing lead ion efficiently including 0.207 g/L original Pb2+ concentration, pH 4.5, 0.08 kg/L bacteria concentration, adsorbing for 6 hours in solution. The absorbing rate can reach over 60%. This experiment will provide theoretical and technical support for the control of contamination caused by lead ion in waste water.