COPPER BINDING BY INACTIVATED CELLS OF MUCOR ROUXII

J.L. Gardea-Torresdey¹, I. Cano-Aguilera¹, K.J. Tiemann¹, R. Webb² and F. Gutiérrez-Corona³

¹Chemistry Department, University of Texas at El Paso, El Paso, TX 79968, 915-747-5359, FAX 915-747-5748; ²Department of Biological Sciences, University of Texas at El Paso, El Paso, TX; and ³Instituto de Investigación en Biología Experimental (IIBE), Facultad de Química, Universidad de Guanajuato, Guanajuato, Gto., México


ABSTRACT

Inactivated copper-sensitive and copper-tolerant strains of Mucor rouxii cultured at high copper concentration were tested for their potential to adsorb Cu(II) ions from solution. We performed batch experiments to determine the pH profile for Cu(II) binding, binding capacity and the possibility of removing the Cu(II) that had been adsorbed. The biomasses studied showed a high affinity for Cu(II) ions as the pH increased from 2 to 5. The copper-tolerant strain exhibited a higher copper adsorption than the copper-sensitive strain. Most of the Cu(II) adsorbed by the inactivated cells was desorbed by treatment with 0.1 M HCl. We investigated the mechanisms involved in Cu(II) binding. We chemically modified the possible carboxyl groups present on the inactivated cells of Mucor rouxii by esterification with methanol. Cu(II) binding decreased approximately 25% after the carboxyl groups were esterified. The Cu(II) binding ability of the esterified carboxyl groups was regained after base hydrolysis. These preliminary findings suggest that the carboxyl groups could be at least in part responsible for Cu(II) binding. This phenomenon can have useful applications for metal-removal from contaminated water.

KEY WORDS

Mucor rouxii, fungi, copper, metal binding, metal-contaminated water

This paper is from the Proceedings of the 10th Annual Conference on Hazardous Waste Research 1995, published in hard copy and on the Web by the Great Plains/Rocky Mountain Hazardous Substance Research Center.


To view the entire paper, you must have Adobe Acrobat Reader. Click here to download Acrobat.

Click here to download the paper. (476 k)