16.3 Biofluorescent Proteins
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green fluorescent protein (GFP), fatty-acid-binding fluorescent proteins and GFPlike proteins and recently bromo-tryptophan kynurenines from catshark (Park et al.
2019). Cyanobacteria such as Spirulina produce phycobiliproteins which are used
to capture light needed for photosynthesis and they also are biofluorescent (Pagels
et al. 2019). The red algae Porphyridium also produces phycobiliproteins (Li et al.
2019). The main types of phycobiliproteins are phycocyanin, phycoerythrin, allophycocyanin and phycoerythrocyanin. These phycobiliproteins have also been found
to have some bioactive properties such as anti-inflammatory, anticancer and antioxidant activities (Pagels et al. 2019). Such that understanding the mechanisms by which
aquatic organisms fluorescence and the polymers which are used for it has lead to
development in other areas.
16.4 Xyloglucan
In most plants, the cell wall comprises cellulose microfibrils in a matrix of hemicellulose and pectin. The hemicellulose is a complex mixture of different polymers. The
most abundant of these polymers is xyloglucan. It is a polymer with a repeating unit
of beta 1-4 D glucans with every sixth glucan replaced by an alpha-d-xylose. This
xylose could further be attached to other units such as fucose, arabinose and galactose
(Hayashi and Kaida 2011). The type of units attached to the xylose varies in different
plant species and affects the property of the xyloglucan. Therefore, xyloglucan from
different species can exhibit different properties such as solubility in water. Although
predominantly in plants, xyloglucan has also been reported to be present in green
algae cell wall (Domozych et al. 2010) although only lower amount compared to the
other cell wall polymers.
Xyloglucans show some gelation properties which have been investigated for
application in developing thermoresponsive drug delivery materials (Sakakibara et al.
2019). They play mainly load-bearing roles in the cell wall, and this is based on
their interaction with cellulose. This interaction with cellulose could be explored for
production of materials with desirable mechanical properties from xyloglucan and
cellulose composites.
16.5 Pectin
Pectin is an anionic polysaccharide with a relatively complex structure. Its polymer
structure comprises beta-1,4-d-galacturonic acid where some or all of the uronic acids
present in the chain form an ester linkage with a methoxy group. This is referred to
as the methoxyl content, and it affects the gel strength and gelling temperature of the
pectin.
The most well-known application of pectin is for its use as a gelling agent in the
production of jams. They also have biomedical applications such as drug delivery
351
green fluorescent protein (GFP), fatty-acid-binding fluorescent proteins and GFPlike proteins and recently bromo-tryptophan kynurenines from catshark (Park et al.
2019). Cyanobacteria such as Spirulina produce phycobiliproteins which are used
to capture light needed for photosynthesis and they also are biofluorescent (Pagels
et al. 2019). The red algae Porphyridium also produces phycobiliproteins (Li et al.
2019). The main types of phycobiliproteins are phycocyanin, phycoerythrin, allophycocyanin and phycoerythrocyanin. These phycobiliproteins have also been found
to have some bioactive properties such as anti-inflammatory, anticancer and antioxidant activities (Pagels et al. 2019). Such that understanding the mechanisms by which
aquatic organisms fluorescence and the polymers which are used for it has lead to
development in other areas.
16.4 Xyloglucan
In most plants, the cell wall comprises cellulose microfibrils in a matrix of hemicellulose and pectin. The hemicellulose is a complex mixture of different polymers. The
most abundant of these polymers is xyloglucan. It is a polymer with a repeating unit
of beta 1-4 D glucans with every sixth glucan replaced by an alpha-d-xylose. This
xylose could further be attached to other units such as fucose, arabinose and galactose
(Hayashi and Kaida 2011). The type of units attached to the xylose varies in different
plant species and affects the property of the xyloglucan. Therefore, xyloglucan from
different species can exhibit different properties such as solubility in water. Although
predominantly in plants, xyloglucan has also been reported to be present in green
algae cell wall (Domozych et al. 2010) although only lower amount compared to the
other cell wall polymers.
Xyloglucans show some gelation properties which have been investigated for
application in developing thermoresponsive drug delivery materials (Sakakibara et al.
2019). They play mainly load-bearing roles in the cell wall, and this is based on
their interaction with cellulose. This interaction with cellulose could be explored for
production of materials with desirable mechanical properties from xyloglucan and
cellulose composites.
16.5 Pectin
Pectin is an anionic polysaccharide with a relatively complex structure. Its polymer
structure comprises beta-1,4-d-galacturonic acid where some or all of the uronic acids
present in the chain form an ester linkage with a methoxy group. This is referred to
as the methoxyl content, and it affects the gel strength and gelling temperature of the
pectin.
The most well-known application of pectin is for its use as a gelling agent in the
production of jams. They also have biomedical applications such as drug delivery