A chromium-resistant fungus isolated from contaminated air with industrial vapors can be used for reducing toxic Cr(VI) to Cr(III). This study analyzes in vitro reduction of hexavalent chromium using cell free extract(s) of the fungus that was characterized based on optimal temperature, pH, use of electron donors, metal ions and initial Cr(VI) concentration in the reaction mixture. This showed the highest activity at 37°C and pH 7.0; there is an increase in Cr(VI) reductase activity with addition of NADH as an electron donor, and it was highly inhibited by Hg2+, Ca2+ and Mg2+, and azide, EDTA, and KCN.

The objective of this work was to study the removal of chromium VI in aqueous solution by the fungus Penicillium sp. IA-, isolated from polluted air with industrial vapors. To obtain the fungal biomass, pre-inoculums were performed in thioglycolate broth from a strain isolated from vapours contaminated with Cr VI . The fungus was incubated for four weeks at ambient temperature, filtered, and washed three times with trideionized water. In preparing cellullar fractions, it was necessary to break the fungal cells with glass beads using a homogenizer being careful to keep the samples in frosty cold ice. To obtain the fungal biomass, the fungus was filtered and stored in an oven at °C, allowing it to dry for h. Removal of Cr VI in vitro was evaluated using different cellular fractions and dead fungal biomass. We determine the optimal characteristics for metal removal in the reaction mixture. Concluding that the ideal conditions for the removal of Cr VI in the cell extracts were °C and pH . , also we observ that the highest enzyme activity was in the mixed membrane fraction. In dead fungal biomass, the ideal conditions for removal of metal are °C and pH . .