Reduction of Cr(VI) by palladized biomass of Desulfovibrio vulgaris NCIMB 8303
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چکیده
Palladized biomass of Desulfovibrio vulgaris (Bio-Pd(0)) reduced Cr(VI) to Cr(III) at an initial rate four-fold higher than chemically-prepared Pd(0) metal. Optimal Cr(VI) reduction by suspended BioPd(0) occurred at pH 3, whereas pH did not affect the rate of Cr(VI) reduction by Bio-Pd(0) immobilized in agar beads. The rate of Cr(VI) reduction was concentration-dependent below 300 μmol dm−3, and application of enzyme kinetics, considering Bio-Pd(0) as an ‘artificial enzyme’, gave an apparent Km (Km app) of approx. 650 μmol dm−3 and Vmax of 1667 nmol h−1 mg Pd(0) for suspended Bio-Pd(0). The potential of Bio-Pd(0) as a method for the treatment of Cr(VI)-wastes is discussed. 2005 Society of Chemical Industry
منابع مشابه
Reduction of Chromate by Desulfovibrio vulgaris and Its c(3) Cytochrome.
Washed cell suspensions of Desulfovibrio vulgaris rapidly reduced Cr(VI) to Cr(III) with H(2) as the electron donor. The c(3) cytochrome from this organism functioned as a Cr(VI) reductase. D. vulgaris may have advantages over previously described Cr(VI) reducers for the bioremediation of Cr(VI)-contaminated waters.
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