Biomedical Engineering Reference
In-Depth Information
4.8. Infra-Red (IR) Spectra of Untreated and Dye-treated
γ
-PGA
The IR spectra of both untreated and dye-treated γ-PGA were almost identical (Figure 10)
[71]. Nevertheless, by critical comparison the presence of two new peaks at ~1600 and
1405.72 cm
-1
in dye-treated γ-PGA could be observed, which are characteristic of asymmetric
and symmetric stretching vibrations of carboxylate anion (COO
-
), respectively [71]. Thus, the
adsorption of cationic dyes on γ-PGA may occur by interaction with carboxylate anions
through exchange of hydrogen ions from the side chain carboxyl groups.
A
B
Figure 10. Infra-Red spectra of untreated γ-PGA (A) and BB-Y dye-treated γ-PGA (B).
5.
γ
-PGA as an Adsorbent of Chemical Mutagens
Many polysaccharides and dietary fibers from vegetables, fruits and cereals are known to
be antimutagenic [116-121]. Nevertheless, the antimutagenic activity of extracellular
polymeric substances derived from bacterial sources remains less explored. Recently, the
