Mycoremediation of Synthetic Dyes: An Insight into the Mechanism, Process Optimization and Reactor Design - Microbial Degradation of Synthetic Dyes in Wastewaters - page 19

reduction in second step. Thus, sequential bioreactors, based on combined aerobic-
anaerobic treatment of dye wastewater, have a large potential. Another approach,
which may be utilized for enhancing removal of dye, is the coupling of two
mechanisms, such as chemical and biological method. Sudarjanto et al. ( 2006 )
integrated the chemical and biological degradation methods to degrade Reactive
Azo Red 195A. For this, two reactors i.e. photoreactor and bioreactor were used in
a series. Advanced oxidation of dye by UV/H 2 O 2 was carried out in photoreactor,
followed by aerobic biodegradation in bioreactor containing microbial bio

lms.
Shoabargh et al. ( 2013 ) have coupled photodegradation and enzymatic process of
Acid Orange 7 dye degradation, using a rectangular recycling photo-bioreactor
containing glucose oxidase (GOx) immobilized on TiO 2 /polyurethane (PU).
Thus, it seems that recent technical advancements, employing combination of
techniques, should be further explored so as to attain a design more suitable for dye
containing ef uents which can be acceptable in terms of inputs required, cost and

time taken for the treatment.

6 Management of Dye Laden Fungal Biomass

The major hindrance faced after dye removal process is the disposal of dye laden
microbial biomass. Only a few studies address to the problem posed by the gen-
eration of dye laden microbial slurry. Nigam et al. ( 2000 ) utilized different agri-
cultural residues, such as wheat straw, wood chips and corn-cob shreds for the
biosorption of mixture of dyes containing Cibacron Red, Remazol Navy Blue,
Remazol Red, Cibacron Orange, Remazol Golden Yellow, Remazol Blue, Remazol
Turquoise Blue and Remazol Black B dyes. After biosorption, the waste slurry is
utilized as a substrate for solid state fermentation by two white-rot fungi; Phan-
erochaete chrysosporium and Coriolus versicolor. After theenzymatic degradation,
the spent fermentation slurry was used as a soil conditioner. A variant approach was
adopted by Kaushik et al. ( 2013 ), wherein the spent fermentation slurry, containing
fungal biomass of A. lentulus and corn cob, was utilized for the biosorption of Acid
Navy Blue dye and the disposal of dye laden slurry was accomplished through
vermicomposting, resulting in the production of compost ideal for disposal in the
soil. Although these studies provide encouraging results to overcome the waste
management problem, still more studies are required in this regard to provide viable
and sustainable options.

7 Future Perspectives

Currently biological removal of synthetic dyes is a widely researched topic. Yet,
certain research gaps can still be identi

ed which are important to be addressed for

eld application of the technology.