There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Bleach plant effluents from the pulp and paper industry generated during bleaching
with chlorine-containing chemicals are highly colored and also partly toxic due to
the presence of chloro-organics, hence the need for pretreatment prior to discharge.
In a rotating biological contactor (RBC) reactor effluent decolorization was studied
using Coriolus versicolor, a white-rot fungus and Rhizomucor pusillus strain RM7,
a mucoralean fungus. Decolorization by both fungi was directly proportional to initial
color intensities. It was found that the extent of decolorization was not adversely
affected by color intensity, except at the lowest level tested. It was shown that
decolorization of 53 to 73% could be attained using a hydraulic retention time of
23 h. With R. pusillus, 55% of AOX were removed compared to 40% by C. versicolor.
Fungal treatment with both R. pusillus and C. versicolor rendered the effluent essentially
nontoxic. Addition of glucose to decolorization media stimulated color removal by
C. versicolor, but not with R. pusillus. Ligninolytic enzymes (manganese peroxidase
and laccase) were only detected in effluent treated by C. versicolor. It seems that
there are definite differences in the decoloring mechanisms between the white-rot
fungus (adsorption + biodegradation) and the mucoralean fungus (adsorption). This
aspect needs to be investigated in greater detail to verify the mode responsible for
the decolorization activity in both types of fungi.