Molecular Plant Breeding 2015, Vol.6, No.14, 1
-
8
5
Figure 3 FTIR spectra of
Marsilea
plant under -0 µM Cd, 50 µM Cd, 100 µM Cd, 200 µM Cd and 200 µM Cd+2 mM spermidine
Table 1 FTIR detected changes in frequencies in different functional groups under Cd induction
Chemical functional group
Structural formula
Frequency in cm
-1
(in the sample)
Alkyl halide
-C-Cl
770-772
Hydroxyl
-OH
3401-3399
Amide
-C=O
1652
Amide
-NH
3401-3399
Alkane (stretched form)
-C-H
2850-3000
Alkane (bending form)
-C-H
1350-1480
Alkyl halide
-C-F
1000-1400
changes in the fingerprint region of 1600-3400 cm
-1
(amide –I and II) are due to excess amount of organic
acids and non-proteinaceous or carbohydrate residues
under exposure of Cd , Cu, Pb, Cr and Zn (Bartosova
et al., 2013). Therefore, Cd being a heavy metal was
bio-adsorbed on the cell surfaces with the contribution
of a few functional groups like amide, hydroxyl,
amine etc. and that also evident in the present
experiment with
Marsilea
. Again, a linear decrease in
frequency (772.21-770.64 cm
-1
) was observed from
control biomass up to 200 µM of Cd treatment. More
so, an increase in absorption frequency (772.21 cm
-1
)
was noted in the biomass supplemented with Spd
(Figure 3). This arises from the possible the
interactive phenomenon of carboxyl group (–COOH)
with Cd. This is well in conformity that presence of
–COOH from different nucleophilic species those
could furnish the bonding strength with divalent
cations (Cd could be of those). However,
Marsilea
plant, being a typical water fern in nature has also
registered the similar kind of metal induced damages
mainly by direct loss of potassium ion (K
+
) etc along
with some modification in cell wall components.
Again Spd treatment has been evident to encounter in
such a way that more possibly the alkyl halide (-C-Cl)
groups are less stretched with moderate bending. So,
alkyl halide evokes the possibility of most sensitive
chemical residue furnishing the bio-adsorption of Cd
in
Marsilea
. The major changes for three principal
bio-molecules like carbohydrate, protein and lipid of
their absorption variation at different wave length
were given in Table 2. This may also be resumed
that physical and chemical conformity of the cell
wall and its plasticity could be the minimum requirement
