Enzymatic study of activated sludge in aerobic—anaerobic run

Abstract
For the biological removal of phosphate during wastewater treatment an alternance of anaerobic and aerobic zones is necessary. Eight enzymes of the energy metabolism were determined in activated sludge during aerobic‐anaerobic operation. No change of enzymatic activity could be determined when pilot plant sludge were switched from aerobic to anaerobic conditions, but this continuous alternation profondly changes the oxidative metabolism of the microorganisms as compared with a conventional treatment plant, especially for the tricarboxylic cycle.