Page 100 - Refining Biomass Residues for Sustainable Energy and Bioproducts

Microbial-derived natural bioproducts for a sustainable environment 73

reconstruction and guided bone regeneration) and wound healing. Gellan sulfate
derivatives have a capacity of selective binding to fibronectin molecules and also
have anticoagulant activity (Roca et al., 2015). An EPS named as Clavan (contain-
ing L-fucose) has potential in preventing tumor cell colonization, for the treatment
of rheumatoid arthritis and also has application in the synthesis of antigen for anti-
body production, in controlling WBCs formation and as a skin moisturizing agent
in cosmeceuticals (Kumar et al., 2007). Heparin-like EPS produced by Alteromonas
infernus isolated from deep-sea hydrothermal-vents has anticoagulant property
(Kumar et al., 2007).

3.5.2.3 Bioremediation
Most of the EPS produced by microorganisms have metal ion binding capability of
making them suitable for metal biosorption and bioremediation process. This metal
ion complexation property of EPS is contributed by their polysaccharides and pro-
tein moieties containing negatively charged amino acids, such as glutamic acid and
aspartic acid. It is observed that EPS was able to chelate and bind metals, such as
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Th 41 and Al , to the bacterial cell surface. A study reported more than 90% of
metal adsorption at an EPS concentration of 67 and 160 mg/L using two different
bacterial strains. Both EPS and bacterial cells have shown a strong affinity to bind
ions, such as Mn, Pb, and Cu (Nouha et al., 2018). An EPS obtained from marine
bacterial strain Zooglea sp. has been studied for the absorption of metals, such as
Cr, Pb, and Fe, in solutions (Kumar et al., 2007). EPS produced by Alteromonas
macleodii subsp. fijiensis, xanthan shows high metal binding capacity (up to
316 mg Pb(II)/g) (Poli et al., 2010). Novel and improved applications of EPS, such
as sequestration of toxic compounds, settling of activated sludge, elastic absorbent
formation for CO 2 absorption, and incorporation of clay nanoparticles in aqueous
foams for suppressing vaporization of gasoline, are under research (Freitas et al.,
2011).

3.5.2.4 Pharmaceuticals
Gellan gum has been studied for drug delivery in the form of tablets, hydrogels,
capsules, and gellan gum based formulations for oral, ophthalmic, and nasal appli-
cations that are also developed (Roca et al., 2015). Fucogel containing fucose sugar
has moisturizing and antiaging properties and has been extensively used in cosmetic
formulations for skin care (Roca et al., 2015). The LAB’s exopolysaccharide has
been reported for its physiological and biological functions, such as antioxidant,
antibiofilm, antitumor, antibacterial, immunoregulatory function, anticoagulant, and
cholesterol-lowering activities (Rajoka et al., 2018; Zhou et al., 2018). Due to high
fucose content present in fucoPol, it is used in antitumor, immune-cancer, and anti-
inflammatory drugs (Freitas et al., 2011). Rhamnose and fucose containing oligo
and polysaccharides are used in treatment for skin aging (Roca et al., 2015). Recent
research is focusing on the formation of novel structures (such as polymer beads,
micro/nanospheres, and capsules) composed of safe edible materials in which