Molecular Plant Breeding 2016, Vol.7, No.9, 1-16
http:// mpb.biopublisher.ca
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compounds also results in the induction of laccase in
Ascomycetes. During asexual development in A.
nidulans,
yA gene (a gene encoding the
developmentally regulated enzyme conidial laccase)
plays crucial role (Aramayo and Timberlake, 1990).
Scherer and Fisher, (2001) found second and third
(tilA) laccase at the sexual phase and in the vegetative
cells at hyphal tip respectively, although tilA exhibits
lower expression.
et al., (2010) described
that laccases have ability to make processing of food
economically and ecofriendly. Excessive availability
of laccase in different fungal genera confirms their
wide occurrence in fungi specifically in white rot
fungi (Revankar and Lele, 2006). Agematu et al.,
(1993) reported that laccases are secretory enzymes
and are released in the media by different filamentous
fungi. The laccase gene sequences amplified and
sequenced from G. lucidium, P. brevispora and
Trametes exhibit 65-74% nucleotide sequence
homology (Galhaup et al., 2002). According to Lyons
et al., (2003) fungal species belonging to Ascomycota
possess differnt laccase encoding genes which are
involved in the oxidization of syringaldazine dye.
In order to enhance production of laccase there is
increased research trend towards utilization of
recombinant fungal strains. Abyanova et al., (2010)
has performed many experiments to transfer the
laccase genes of T. hirsute into the P. canescens, an
ascomycete fungus for heterologous expression and
determined that after successful transformation 98%
enzyme activity was visible in liquid culture medium.
Genes coding for several laccases from Trametes C30
have been sequenced and cloned in S. cerevisiae. This
will make possible to produce large amount of
enzymes which are produced in low quantity by the
fungus itself (Klonowska et al., 2005). It is the need of
hour to move ahead in the field of research to confirm
high laccase production by applying large scale
fermentation methods. Germann and Lerch, (1986)
cloned the laccase gene from N. crassa and its
nucleotide sequence was determined.
3.2 Superoxide dismutase (SOD) enzyme
Superoxide dismutase is present in all living
organisms that efficiently transform superoxide (O2-)
into hydrogen peroxide (H2O2) and molecular oxygen
(Fridovich, 1995). The different types of superoxide
dismutase enzyme required different cofactors,
including copper, zinc, manganese, iron or nickel.
Superoxide dismutase is ubiquitous in nature and on
the basis of metal cofactors there are three main SOD
families, while Cu-Zn-SOD present in the cytosol of
eukaryotes (Tainer et al., 1983; Javed et al., 2015). It
was revealed by Gregory et al., (1973) that this is
present in all oxygen metabolizing cells. Superoxide
oxide dismutase has been found and purified in
different organisms, including fungus N. crassa,
bacterium E. coli, green peas and wheat (Misra and
Fridivich, 1972; Beauchamp and Fridovich, 1973).
Superoxie dismutases are universal protective tools
that protect the cell from damage and well described
in prokaryotic and eukaryotic cells (Frohner et al.,
2009). They have also been reported from anaerobic
bacteria by Hewitt and Morris (1975). Moore et al.,
(2002) described that in filamentous fungi SODs have
rarely been reported, as compare to prokaryotic cells
and they have many Cu-Zn-SODs. Expression of
Cu-Zn-SOD and Fe-SOD did not change considerably
during the process of mycorrhizal development in
plants (Liu et al., 2003;
et al., 2005).
Superoxide is reactive species with ability to react
with different substances that result from metabolic
processes. Superoxide dismutase enzymes found in
aerobic and anaerobic organisms catalyze the
breakdown of superoxide radical (Shirwaikar and
Punitha, 2007). The scavenging ability of plant
extracts superoxide is perhaps due to the presence of
flavonoids (Zheng et al., 2008).
Zheng et al., (2008) studied the antioxidant activity of
Tolypocladium fungus was obtained from wild C.
sinesis, an endangered species. Tolypocladium sp. Ts-1
was isolated from fruiting body of a wild C. sinensis,
one of the well reputed traditional Chinese medicine
and health foods. Hot water extracts obtained from
cultured mycelia of Tolypocladium sp. were analyzed
through different systems in vitro. The extracts showed
superoxide dismutase (SOD) activity of 35.6 U/mg
proteins and are involved in scavenging superoxide
radical in concentration dependent manner with IC50
value of 1.3 mg/mL. Using deoxyribose assay method,
analogous radical scavenging action was determined
both with site specific and non-site specific hydroxyl
radicals. The aqueous extract of Tolypocladium sp.
mycelium has strong antioxidant activities and hss a
