recycle organic nutrients in agriculture. Vermicomposting involves bio-oxidation
and stabilization of OM by the combined action of microorganisms and earthworms.
Earthworms develop a mutualistic relationship with soil microflora which gives
them the ability to digest and convert low-quality OM into a nutrient-rich
vermicompost (biofertilizer). Bioremediation of distillery sludge through
vermicomposting with the help of Eisenia fetida has been studied by Singh et al.
(2014). They concluded that distillery sludge can be stabilized by vermicomposting
in a short span of approximately 150 days but only when it is mixed with a bulking
agent (cattle dung) in at least 1:1 ratio, as 100% sludge is noxious to the worms for
quite a long time. Better physicochemical characteristics and earlier stabilization
(higher electrical conductivity and low C/N ratio) of the mixtures make
vermicomposting a better option over composting (without earthworm) for bioremediation of distillery sludge. The feasibility of vermicomposting technology to
stabilize the distillery sludge mixed with cow dung in different extents, viz., 20%,
40%, 60%, and 80%, was tested by Suthar and Singh (2008) using composting
earthworm Perionyx excavatus for 90 days. They found that vermicomposting also
caused a considerable reduction in the total concentration of metals: Cu
(8.6–39.6%), Fe (5.2–29.8%), Mn (2.6–36.5%), and Zn (15.1–39.6%) in sludge.
Mahaly et al. (2018) also studied the feasibility of vermicomposting technology for
management of distillery sludge waste (DSW) combined with tea leaf residues
(TLR). DSW and TLR were combined in different ratios and subject to
vermicomposting for a period of 45 days using the Eisenia fetida. The physicochemical properties of vermicompost sample showed that the values of pH, total
potassium, total phosphorus, available K, P, TN, total magnesium, and total calcium
were increased with a declining trend in EC, total organic carbon (TOC), and C/N
ratio from its initial value.
5.2 Ex Situ Bioremediation of Distillery Waste
5.2.1 Mycoremediation of Distillery Waste
Fungi are eminent microorganisms to remove and degrade melanoidins and have
been extensively studied (Sirianuntapiboon et al. 2004; Sing and Dikshit 2011;
Kaushik and Thakur 2013). White rot fungi, which comprise of several hundred
species of Basidiomycetes and a few species of Ascomycetes, are believed to be the
most efficient degraders of melanoidins. Phanerochaete chrysosporium and
Trametes versicolor are the most widely studied for the decolorization and degradation of melanoidin containing distillery effluent. The aim of fungal treatment is to
purify the distillery effluent by consumption of organic substances, thus reducing its
BOD and COD, and at the same time to obtain some value-added products, such as
fungal biomass for protein-rich animal feed, extracellular organic acids, or some
specific fungal metabolites. There were several reports that indicated that some fungi
such as Coriolus hirsutus, Citeromyces sp., Aspergillus oryzae, Fusarium
20 Bioremediation of Melanoidins Containing Distillery Waste for. . .
511
and stabilization of OM by the combined action of microorganisms and earthworms.
Earthworms develop a mutualistic relationship with soil microflora which gives
them the ability to digest and convert low-quality OM into a nutrient-rich
vermicompost (biofertilizer). Bioremediation of distillery sludge through
vermicomposting with the help of Eisenia fetida has been studied by Singh et al.
(2014). They concluded that distillery sludge can be stabilized by vermicomposting
in a short span of approximately 150 days but only when it is mixed with a bulking
agent (cattle dung) in at least 1:1 ratio, as 100% sludge is noxious to the worms for
quite a long time. Better physicochemical characteristics and earlier stabilization
(higher electrical conductivity and low C/N ratio) of the mixtures make
vermicomposting a better option over composting (without earthworm) for bioremediation of distillery sludge. The feasibility of vermicomposting technology to
stabilize the distillery sludge mixed with cow dung in different extents, viz., 20%,
40%, 60%, and 80%, was tested by Suthar and Singh (2008) using composting
earthworm Perionyx excavatus for 90 days. They found that vermicomposting also
caused a considerable reduction in the total concentration of metals: Cu
(8.6–39.6%), Fe (5.2–29.8%), Mn (2.6–36.5%), and Zn (15.1–39.6%) in sludge.
Mahaly et al. (2018) also studied the feasibility of vermicomposting technology for
management of distillery sludge waste (DSW) combined with tea leaf residues
(TLR). DSW and TLR were combined in different ratios and subject to
vermicomposting for a period of 45 days using the Eisenia fetida. The physicochemical properties of vermicompost sample showed that the values of pH, total
potassium, total phosphorus, available K, P, TN, total magnesium, and total calcium
were increased with a declining trend in EC, total organic carbon (TOC), and C/N
ratio from its initial value.
5.2 Ex Situ Bioremediation of Distillery Waste
5.2.1 Mycoremediation of Distillery Waste
Fungi are eminent microorganisms to remove and degrade melanoidins and have
been extensively studied (Sirianuntapiboon et al. 2004; Sing and Dikshit 2011;
Kaushik and Thakur 2013). White rot fungi, which comprise of several hundred
species of Basidiomycetes and a few species of Ascomycetes, are believed to be the
most efficient degraders of melanoidins. Phanerochaete chrysosporium and
Trametes versicolor are the most widely studied for the decolorization and degradation of melanoidin containing distillery effluent. The aim of fungal treatment is to
purify the distillery effluent by consumption of organic substances, thus reducing its
BOD and COD, and at the same time to obtain some value-added products, such as
fungal biomass for protein-rich animal feed, extracellular organic acids, or some
specific fungal metabolites. There were several reports that indicated that some fungi
such as Coriolus hirsutus, Citeromyces sp., Aspergillus oryzae, Fusarium
20 Bioremediation of Melanoidins Containing Distillery Waste for. . .
511