One suggestion for desorbing bacteria from iron flocs would be to lower the
pH.
Typically anionic bacterial cell surfaces bind Fe quite well, however the iron
will dissociate in the presence of H+ ions (i.e. low pH) generally below pH
5.
Alternatively, Fe flocs can be dissolved if the mixture is subjected to
reducing conditions. A few years ago, I did a study on this phenomenon. The
journal citation is:
R.J.C. McLean, D. Beauchemin, and T.J. Beveridge. 1992. Influence of
oxidation
state on iron binding by Bacillus licheniformis capsule. Appl. Environ.
Microbiol. 58: 405 - 408.
Good luck
Bob McLean
Dept. Biology
Southwest Texas State University
San Marcos, Tx 78666
USA
(512)245-3365 phone
(512)245-8713 FAX
Email: RM12 at swt.edu
