Use of Fungal Laccases and Peroxidases for Enzymatic Treatment of Wastewater Containing Synthetic Dyes - Green Chemistry for Dyes Removal from Wastewater - page 231

and Brock [22] earlier. Verma and Madamwar [144] produced P. c h r y s o -
sporium LiP using neem hull waste under solid-substrate fermentation
conditions and evaluated the use of produced enzyme for decolorization
of various dyes, including Reactive Blue 4, Acid Red 119, Acid Black 194,
and Ranocid Fast Blue. The highest decolorization was observed at pH 5.0
in all cases. Verma and Madamwar [145] also attempted co-cultivation of
P. chrysosporium and P. ostreatus to improve the enzyme production using
the lignocellulosic wastes. In this case, laccase and MnP were also pro-
duced and crude enzyme mixtures were prepared and used to decolorize
several different dyes. Significant decolorization (73% to 91%) occurred in
the absence of hydrogen peroxide using the crude enzyme mixtures.
6.6.2 Manganese-DependentPeroxidases
Isolated and purified MnP from the culture of white rot fungi has been
used to decolorize a number of synthetic dyes. It appears that the use of
isolated MnP attracted more attention in the recent years, although the
number of reports is still relatively small. Also, the identities of produced
enzymes were often ambiguous in these papers at the time of publication.
There might be some confusion between MnP and versatile peroxidase
and/or DyP.
Moldes et al. [146] reported the use of P. chrysosporium and its MnP
in a fixed-bed bioreactor for the decolorization of an anthraquinone dye,
Poly R-478, and a triarylmethane dye, Basic Violet 3. They used crude MnP
preparation (approximately 1,000 U/L) produced by ultrafiltration of extra-
cellular liquid. By using the continuous addition of MnP, hydrogen perox-
ide, sodium malonate, and manganese sulfate, they could achieve up to
70% and 30% of Poly R-478 and Basic Violet 3 decolorization, respectively,
in two hours. Cheng et al. [147] isolated a new MnP from Schizophyllum
sp. and used the enzyme to decolorize several azo/diazo dyes, including
Direct Red 28, Acid Orange 5, and Acid Orange 10. They noticed rapid
decolorization of 1 mM of Acid Orange 5 with 20 U/L of purified MnP, 0.1
mM of H 2 O 2 , and 1 mM of manganese(II) sulfate.
Heinfling et al. [148] investigated the decolorization of four azo/diazo
dyes (Reactive Violet 5, Reactive Black 5, Reactive Orange 96, and Reactive
Red 198) and two phthalocyanine dyes (Reactive Blue 38 and Reactive
Blue 15) using MnP from the culture fluids of B. adusta and P. eryngii .
They found that the MnP from B. adusta oxidizes those dyes in a manga-
nese independent manner, which was known with MnP isozymes from
Pleurotus spp. (such as P. ostreatus and P. eryngii ). Shin and Kim [149]