The results showed that the
anaerobic degradation of CODcol produced higher fraction of
CODss and CODdis. Moreover, the anaerobic degradation of
CODss and CODdis produced higher fraction of CODcol. The
higher production of CODss from the degradation of influent
CODcol might be due the production of anaerobic bacteria and
bioflocculation of the colloids and the produced bacteria. It is
well known that many living microorganisms have a flocculent
growth habit and produce extracellular polymers, usually
polysaccharides, polypeptides or peptidoglycans, which enhance
biosorption of particles (Dugan, 1987).