Prajapati et al.
Bevandamm’s reaction for positive ligninolytic enzyme
3.3 Screening of decolorization of different dyes by
activity (Fig. 1C). However, the intensity of the color
fungal isolate AGYP-1
produced by AGYP-1 was much higher as compared to
Industrial effluent contains varieties of dyes with different
AGYP-4, suggesting greater production of ligninolytic
structural and functional properties. Therefore, it is
enzymes.
important to assess the capability of microorganisms to
3.2 Decolorization of Reactive Red M5B by fungal
decolorizevariousdyes.A varyingdegreeofdecolorization
isolates in liquid medium
of different dyes was obtained by the isolate AGYP-1
(Table 1). The isolate displayed maximum decolorization
Since long, the use of fungi has attracted increasing
of Reactive Red M5B (91.36±4.8) followed by Reactive
scientific attention, as they are able to degrade a
Blue 3R (88.58±5.9%). The decolorization of Acid Green
wide range of recalcitrant organic compounds due to
GLW, Reactive Red HE8B and Reactive Violet 5R
production of an array of highly efficient nonspecific
was in the range of 65.0±5.3 to 86.54±4.8%. The dyes
ligninolytic enzymes (Christian et al ., 2005; Nozaki
Reactive Red BS, Acid Red BB and Acid Maroon V were
et al ., 2008). The color removal ability of the fungal
decolorized moderately with decolorization between
isolates was checked in MM amended with 100 mg l -1
45.97±3.5 and 51.22±3.6%, whereas, the decolorization of
Reactive Red M5B. As depicted in Figure 2, maximum
Acid Red 3BN was 10.69±2.2%. The observed variation
decolorization of the dye (91.65±3.4%) was obtained with
in decolorization may be due to structural diversity of
AGYP-1 on 12 th day of incubation. The color removal
dyes. It is observed that dyes with simple structures and
performances of AGYP-3 and AGYP-4 were 71.16±4.3%
low molecular weight are decolorized faster. On the other
and 74.32±2.2% respectively. The lowest decolorization
hand, highly substituted, high molecular weight dyes are
of the dye (35.66±1.3%) was achieved by AGYP-2
prone to decolorize slowly. Moreover, the number of azo
indicating poor color removal ability of the isolate.
bonds and substitution of electron withdrawing groups
The superior decolorization activity of AGYP-1 may
(-SO 3 H, -SO 2 NH 2 ) in dye molecule also confer the extent
be correlated with maximum biomass production along
of color removal (Sani and Banerjee, 1999). The results
with concomitant production of ligninolytic enzymes.
thus illustrate the efficiency of the isolate AGYP-1 for
An effectiveness of white rot fungi for the decolorization
decolorization of different dyes and hence, its potential
of different synthetic dyes has been well documented
application for the treatment of multiple dyes containing
(Erkurt et al ., 2007; Yang et al ., 2009).
industrial effluent.
Figure 2: Time course study of decolorization of Reactive
Red M5B (100 mg l -1 ) by isolated fungal cultures in liquid
Figure 3: Decolorization of Reactive Red M5B by isolate
medium
AGYP-1 under static and shaking conditions
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