Glucose promotes the reduction of hexavalent chromium in soil

In this study we evaluated the dynamics of Cr(VI) reduction in contaminated soil amended or not with glucose together with investigation on its effects on soil microbial biomass size and activity. The influence of native or glucose-induced soil microbial biomass on chromate reduction was assessed. During the incubation period, the concentration of Cr(VI) in soil decreased over time whether glucose was added to soil or not, but with different reduction rates. Soil displayed a natural capacity towards chromate reduction, but the addition of glucose increased the reduction rate by both abiotic and biotic mechanisms. Cr(VI) negatively affected both the size and activity of soil microbial biomass. However, our data suggest that glucose is likely to have exerted an indirect role in the increased rate of Cr(VI) reduction, by promoting growth of indigenous microbial biomass.