Biosorption of cadmium by Enterobacter ludwigii isolated from soil contaminated with cadmium near a coal-fired power plant in Korea

Abstract

ABSTRACT This study aimed to isolate and characterize indigenous bacteria from cadmium-contaminated soil around a coal-fired power plant in Korea for their potential use in biosorption. The 16S ribosomal RNA analysis identified Enterobacter ludwigii G17–1 in the soil, exhibiting a remarkably high minimum inhibitory concentration (2,500 mg/L) for cadmium. The efficiency of cadmium biosorption was investigated under different pH levels (6–9), temperatures (15–40°C), and initial cadmium concentrations (25–100 mg/L), using both live and dead G17–1. The live G17–1 strain exhibited a maximum biosorption efficiency of 50% for 25 mg/L cadmium at 24 hours, while the highest efficiency achieved with dead G17–1 was 48% at 1 hour. The biosorption capacity decreased as the initial cadmium concentration increased. These findings suggest that the isolated bacterium, E. ludwigii G17–1, holds potential for the bioremediation of cadmium-contaminated water and wastewater.