8.2 Treatment with Bacteria
Currently, research works suggest that the use of ligninolytic bacterial system is a
promising approach for the degradation/decolorization of paper industry wastewater.
The large number of bacterial spp. has been employed for the degradation of paper
mill effluent, and some of them are now being used commercially for this purpose.
Flask-scale studies with the bacterial spp. (Bacillus subtilis, Micrococcus luteus,
Pseudomonas aeruginosa, Bacillus cereus, Pseudomonas putida, Acinetobacter
calcoaceticus, Ancylobacter, Methylobacterium, Citrobater, Enterobacter) have
been well reported to reduce color (50–97%), BOD (80–96%), COD (80–97%),
lignin (50–97%), and AOX in paper mill effluent (Tyagi et al. 2014; Ramsay and
Nguyen 2002; Tiku et al. 2010; Raj et al. 2007; Abd-ElRahim and Zaki 2005;
Keharia and Madamwar 2003; Tiku et al. 2010). Numerous studies have been
reported that bacteria can degrade monomeric lignin substructure models, while
only few strains are reported to degrade lignin derivatives obtained from different
pulping processes (Hao et al. 2000; Chandra et al. 2011; Chandra and Bharagava
2013). Lignin degradation by bacterial genera, such as Bacillus, Alcaligenes,
Arthrobacter, Nocardia, Pseudomonas, and Streptomyces, has been well reported
(Chandra et al. 2007). Aerobically or anaerobically, lignin is apparently not
biodegraded by neither rapid nor extensive bacterial system. Lignin degradation
has not been most extensively studied in Streptomyces viridosporous and Streptomyces, but a mixed population of bacteria and protozoa derived from lake-bottom
sediment near the effluent kraft paper mill was shown to degrade lignin (Hossain and
Ismail 2015). In a study the use of commercial kraft lignin as sole source of carbon
by Streptomycetes badius and S. viridosporous was characterized by the use of FTIR
and SEC (Abd-ElRahim and Zaki 2005; Chandra et al. 2011). Resin acids are also
found in paper effluent and toxic to aquatic animals, which are reported to be
degraded by many bacterial spp. (Bacillus sp., E. coli, Flavobacterium sp., Pseudomonas, Alcaligenes eutrophus, Arthrobacter, Sphingomonas, Zooglea, Comamonas,
Mortierella isabella, Chaetomium cochliolidae, Corticum sasakii, and Fomes
annosus) (Tiku et al. 2010; Khansorthong and Hunsom 2009; Raj et al. 2014a;
Ramsay and Nguyen 2002). The studies of Tiku et al. (2010) and Aftab et al. (2011)
using Burkholderia cepacia were interesting as they showed that organism was able
to hydrolyze triglycerides to free fatty acids and liberated unsaturated fatty acids
were then degraded to some extent and saturated fatty acids were not degraded.
Nearly 30% of the stearyl esters, 25% of the dehydroabietic, and 45% of the abietic
and isopimaric resin acids were degraded during 11 days by increasing the concentration of free sterols. The degree of unsaturation seemed to be of greater importance
for the degradation of fatty acids. The induction of ligninolytic enzyme (laccase,
lignin peroxidases, and manganese peroxidases) during bioremediation of rayon
grade pulp and paper mill effluent by a bacterial consortium of Pseudochrobactrum
glaciale, Providencia rettgeri, and Pantoea sp. has been proven by Chandra and
Singh (2012). The consortium of these bacteria effectively reduced lignin and
chlorophenol (90%) within 216 h of treatment. The recent study by Raj et al.
350
I. Haq and A. Raj
Currently, research works suggest that the use of ligninolytic bacterial system is a
promising approach for the degradation/decolorization of paper industry wastewater.
The large number of bacterial spp. has been employed for the degradation of paper
mill effluent, and some of them are now being used commercially for this purpose.
Flask-scale studies with the bacterial spp. (Bacillus subtilis, Micrococcus luteus,
Pseudomonas aeruginosa, Bacillus cereus, Pseudomonas putida, Acinetobacter
calcoaceticus, Ancylobacter, Methylobacterium, Citrobater, Enterobacter) have
been well reported to reduce color (50–97%), BOD (80–96%), COD (80–97%),
lignin (50–97%), and AOX in paper mill effluent (Tyagi et al. 2014; Ramsay and
Nguyen 2002; Tiku et al. 2010; Raj et al. 2007; Abd-ElRahim and Zaki 2005;
Keharia and Madamwar 2003; Tiku et al. 2010). Numerous studies have been
reported that bacteria can degrade monomeric lignin substructure models, while
only few strains are reported to degrade lignin derivatives obtained from different
pulping processes (Hao et al. 2000; Chandra et al. 2011; Chandra and Bharagava
2013). Lignin degradation by bacterial genera, such as Bacillus, Alcaligenes,
Arthrobacter, Nocardia, Pseudomonas, and Streptomyces, has been well reported
(Chandra et al. 2007). Aerobically or anaerobically, lignin is apparently not
biodegraded by neither rapid nor extensive bacterial system. Lignin degradation
has not been most extensively studied in Streptomyces viridosporous and Streptomyces, but a mixed population of bacteria and protozoa derived from lake-bottom
sediment near the effluent kraft paper mill was shown to degrade lignin (Hossain and
Ismail 2015). In a study the use of commercial kraft lignin as sole source of carbon
by Streptomycetes badius and S. viridosporous was characterized by the use of FTIR
and SEC (Abd-ElRahim and Zaki 2005; Chandra et al. 2011). Resin acids are also
found in paper effluent and toxic to aquatic animals, which are reported to be
degraded by many bacterial spp. (Bacillus sp., E. coli, Flavobacterium sp., Pseudomonas, Alcaligenes eutrophus, Arthrobacter, Sphingomonas, Zooglea, Comamonas,
Mortierella isabella, Chaetomium cochliolidae, Corticum sasakii, and Fomes
annosus) (Tiku et al. 2010; Khansorthong and Hunsom 2009; Raj et al. 2014a;
Ramsay and Nguyen 2002). The studies of Tiku et al. (2010) and Aftab et al. (2011)
using Burkholderia cepacia were interesting as they showed that organism was able
to hydrolyze triglycerides to free fatty acids and liberated unsaturated fatty acids
were then degraded to some extent and saturated fatty acids were not degraded.
Nearly 30% of the stearyl esters, 25% of the dehydroabietic, and 45% of the abietic
and isopimaric resin acids were degraded during 11 days by increasing the concentration of free sterols. The degree of unsaturation seemed to be of greater importance
for the degradation of fatty acids. The induction of ligninolytic enzyme (laccase,
lignin peroxidases, and manganese peroxidases) during bioremediation of rayon
grade pulp and paper mill effluent by a bacterial consortium of Pseudochrobactrum
glaciale, Providencia rettgeri, and Pantoea sp. has been proven by Chandra and
Singh (2012). The consortium of these bacteria effectively reduced lignin and
chlorophenol (90%) within 216 h of treatment. The recent study by Raj et al.
350
I. Haq and A. Raj