Abstract
This paper focuses on the identification and analysis of the ability of Pseudomonas fluorescens to reduce chromium (VI) in aqueous media. To develop this bio-reduction capability, microorganisms which potentially can grow in a medium containing up to 100 mg/L of chromium, were selected and used. In order to determine the extension of the reduction of hexavalent chromiun (VI) in lab water, samples of 20 and 50 mg/L were added with 5, 10 and 15 % of final inoculum, respectively to the volume of the samples. Inoculum had a population of approximately 12x108 CFU/mL. Results suggest the occurrence of reduction in all the samples studied. This reduction occurred significantly in the tests P-20.5, P-20.10 and P-20.15, which yielded a reduction of chromium (VI) of 3.6, 1.88 and 5.95 mg/L respectively, for samples P-50.5, P-50.10 and P-50.15 were obtained reductions of 2.36, 4.19 and 4.47 mg/L. The highest levels of bio-reduction were obtained in P-20.15 and P-50.15 tests.
