Congo Red Decolorizing Bacteria from Paper Factory Effluent - Microbial Degradation of Synthetic Dyes in Wastewaters - page 135

Fig. 3 Decolorization of
polluted water by
monocultures and consortia.
Left to right Uninoculated
polluted water with Congo
red as negative control
(CTRL), IRRI-1C, SB12D
and SB13B
Fig. 4 No decolorization of
clean water by monocultures
and consortia. Left to right
SB12D and uninoculated
clean water with Congo red as
negative control (CTRL)
Another explanation could be that they were not exposed to azo dyes prior to the
experiment and hence, they were not adapted to the presence of the dye. Bacteria
need to be adapted to the pollutant before they can degrade it (Baker and Herson
1994 ). In the clean water with less or no organic matter present, decolorization of
Congo red by the CRDB and consortia did not occur. One explanation could be that
the CRDB and consortia were not able to grow due to less or absence of organic
matter that provide nutrients to the organisms. The environmental condition must be