Abstract:Cadmium（Cd2+）-resistant yeast strains were isolated using red acid soup from Kaili，Guizhou province，China，as the source. Using the coating method and stepwise domestication，a yeast strain with high Cd2+-resistance was obtained by screening and was identified.The optimum conditions for Cd2+adsorption by this yeast were studied；Moreover，surface group masking experiments and scanning electron microscopy were used to understand the mechanism underlying Cd2+ adsorption. An isolated strain ST2 that tolerated a maximum Cd2+concentration of 4 000 mg/L was identified as Wickerhamomyces anomalus.The optimum conditions required for Cd2+adsorption were a pH value of 6.5，incubation temperature of 30 ℃，adsorption time of 1.0 h，bacterial joiner concentration of 2.00%，and Cd2+ concentration of 50 mg/L. Optimization resulted in Cd2+adsorption of 55.71%，and an adsorption amount of 4.29 mg/g.After masking the carboxyl，amino，and hydroxyl groups of the strain，the adsorption rate decreased by 19.79%，25.95% and 25.95%，respectively. The contribution of the amino and hydroxyl groups was greater than that of carboxyl groups.Scanning spectroscopy showed the presence of granular aggregates on the surface，and the absorption peak corresponded to that of cadmium. Our findings indicate that the strain ST2，isolated from red acid soup，has a good Cd2+adsorption potential，and can provide a theoretical basis for the microbial adsorption and removal of Cd2+from food products.