Microbial Decolorization of Triphenylmethane Dyes - Microbial Degradation of Synthetic Dyes in Wastewaters - page 169

of Crystal violet, Bromophenol blue and Malachite green was performed by six
white rot fungi isolated from nature.
Also ascomycete fungi, exhibiting expansive growth, great biomass production
and a high cell surface-to-volume ratio resulting in strong physical contact with the
environment, are reported to be useful in the removal of various xenobiotics,
including TPM dyes (Haritash and Kaushik 2009 ; Ali 2010 ). Many of them have
origin from environments (soil, ef uents and sludges) contaminated with dyes. For

example, fungi derived from seawater, marine sediments and seagrass, identi

ed as
Phialophora sp., Penicillium sp. and Cladosporium sp. were shown to completely
decolorize Crystal violet (Torres et al. 2011 ). Aspergillus sp. CB-TKL-1, isolated
from a water sample, was found to be capable of quick decolorization of several
structurally different dyes, especially Methyl violet (Kumar et al. 2011 ) and Bril-
liant green (Kumar et al. 2012 ). Mycelium of Aspergillus ochraceus NCIM-1146,
maintained in water, decolorized Malachite green, Cotton blue, Crystal violet and
Methyl violet with the ef ciency of 98, 92, 61 and 57 %, respectively. This process

involved microbial metabolism, not biosorption (Saratale et al. 2006 ). Fusarium
solani isolated from dye containing ef uents was able to decolorize with a high

ef ciency Malachite green and Crystal violet via biosorption, followed by intra-

cellular degradation to colorless metabolites (Abedin 2008 ). A similar pattern of
Malachite green removal was described for Penicillium pinophilum IM 6480 and
Myrothecium roridum IM 6482, fungi isolated from soil around a textile dyeing
factory (Jasi ska et al. 2012 ). So far, very little work has been done to establish the

TPM dyes decolorization ability of yeast. Strains of Saccharomyces cerevisiae,
Kluyveromyces fragilis, Candida krusei and Galactomyces geotrichum were found
to be ef

ń

cient in decolorization of Malachite green, Crystal violet, Methyl violet,
Cotton blue, Aniline blue and Basic violet 3 (

Š afa ř ikov á et al. 2005 ; Š afa ř ik et al.

2007 ; Jadhav et al. 2008 ; Deivasigamani and Das 2011 ).
Besides, several bacterial strains are able to degrade and even completely
mineralize synthetic dyes (Chen et al. 2011 ; Saratale et al. 2011 ). As compared to
fungi, bacteria are generally easier to culture, grow more quickly and are more
amenable to genetic manipulations. These properties make bacteria a desired object
of research concerning biodegradation of TPM dyes. Members of Pseudomonas,
Bacillus, Citrobacter, Desulfovibrio, Nocardia and Mycobacterium genera are often
recognized as good TPM dyes decolorizers (Oranusi and Mbah 2005 ; Guerra-Lopez
et al. 2007 ; Deng et al. 2008 ; Wu et al. 2009 ). However, in recent years, new
effective decolorant species: Shewanella decolorationis, Acinetobacter calcoaceti-
cus, Aeromonas hydrophila, Achromobacter xylosoxidans, Sphingomonas sp.,
Deinococcus radiodurans, Enterobacter asburiae and Staphylococcus epidermidis
have also been described (Ren et al. 2006 ; Ayed et al. 2010 ; Chen et al. 2011 ;
Wang et al. 2011 ; Wu et al. 2011 ; Lv et al. 2013 ; Mukherjee and Das 2013 ; Pan
et al. 2013 ). Bacteria, examined in the above-mentioned studies, were mostly
isolated from environments contaminated with dyes and usually single strains were
used for TPM decolorization. However, bacterial consortia also occurred to be very
effective in the treatment of ef

uents originating from dyeing processes. Cheriaa
et al. ( 2012 ) reported that a mixed culture containing cells of A. radiobacter,