182
8 Ulvans
bioactivity include U. conglobata, U. compressa, U. flexuosa, U. gigantea and many
others (Kidgell et al. 2019).
8.7.2 Antioxidant
Ulvans like other sulfated polysaccharides act as exogenous antioxidants and enhance
the activities of the endogenous antioxidants. They do so through their radical scavenging activity and enhancement of the activities of antioxidant enzymes. The antioxidant activity of ulvans makes them applicable in addressing a broad range of human
defects which are associated with the presence of reactive oxygen and nitrogen
species. Such conditions include cancer, neurodegenerative diseases, cardiovascular
diseases and aging. Low molecular weight and high sulfate content have been shown
to correlate with the antioxidant activity of ulvans.
Although the mechanism by which ulvans boost endogenous antioxidant activity
is not yet fully established, it is thought that they do this by interfering in signaling
pathways for expression of antioxidant producing enzymes. This ability of ulvans
to stimulate antioxidant enzyme production has been demonstrated by ulvans from
species such as U. amoricana (Berri et al. 2017). Therefore, ulvan antioxidant activity
is both as a result of their chemical structure eliminating oxidative species and also
their ability to influence the gene expression for production of enzymes responsible
for endogenous antioxidant activity in the body.
8.7.3 Anticancer
Although no clinical trials have been reported yet, studies on animals such as mice
and rats and a range of human cancer cell lines such as colon cancer, breast cancer and
gastric cancer cell lines have provided evidence that ulvans could potentially have
anticancer properties. Ulvan from species such as fasciata, tubulosa, pertusa, latusa,
intestinalis and others (Kidgell et al. 2019; Kim et al. 2011b) has shown anticancer
properties.
Various approaches are used in the treatment of cancer: preventing the formation
of cancerous cells by removing factors such as oxidative processes which could lead
to mutation, prevention of growth of the cancer cells or inducing death of the cancer
cells. Thus, far evidence points to ulvans potentially play anticancer roles by either
preventing the proliferation of cancer cells or promoting apoptosis (programmed
cell death) in cancer cells. Example of studies indicates that the ability of ulvans to
promote cancer cell apoptosis is by Wang et al. (2014). In the aforementioned study,
the increase in pro-apoptotic tumor suppressor expression was observed in cancer cell
lines treated with ulvan from Enteromorpha intestinalis. The pro-apoptotic activity of
ulvan is also demonstrated by the reduction in expression of anti-apoptotic proteins.
8 Ulvans
bioactivity include U. conglobata, U. compressa, U. flexuosa, U. gigantea and many
others (Kidgell et al. 2019).
8.7.2 Antioxidant
Ulvans like other sulfated polysaccharides act as exogenous antioxidants and enhance
the activities of the endogenous antioxidants. They do so through their radical scavenging activity and enhancement of the activities of antioxidant enzymes. The antioxidant activity of ulvans makes them applicable in addressing a broad range of human
defects which are associated with the presence of reactive oxygen and nitrogen
species. Such conditions include cancer, neurodegenerative diseases, cardiovascular
diseases and aging. Low molecular weight and high sulfate content have been shown
to correlate with the antioxidant activity of ulvans.
Although the mechanism by which ulvans boost endogenous antioxidant activity
is not yet fully established, it is thought that they do this by interfering in signaling
pathways for expression of antioxidant producing enzymes. This ability of ulvans
to stimulate antioxidant enzyme production has been demonstrated by ulvans from
species such as U. amoricana (Berri et al. 2017). Therefore, ulvan antioxidant activity
is both as a result of their chemical structure eliminating oxidative species and also
their ability to influence the gene expression for production of enzymes responsible
for endogenous antioxidant activity in the body.
8.7.3 Anticancer
Although no clinical trials have been reported yet, studies on animals such as mice
and rats and a range of human cancer cell lines such as colon cancer, breast cancer and
gastric cancer cell lines have provided evidence that ulvans could potentially have
anticancer properties. Ulvan from species such as fasciata, tubulosa, pertusa, latusa,
intestinalis and others (Kidgell et al. 2019; Kim et al. 2011b) has shown anticancer
properties.
Various approaches are used in the treatment of cancer: preventing the formation
of cancerous cells by removing factors such as oxidative processes which could lead
to mutation, prevention of growth of the cancer cells or inducing death of the cancer
cells. Thus, far evidence points to ulvans potentially play anticancer roles by either
preventing the proliferation of cancer cells or promoting apoptosis (programmed
cell death) in cancer cells. Example of studies indicates that the ability of ulvans to
promote cancer cell apoptosis is by Wang et al. (2014). In the aforementioned study,
the increase in pro-apoptotic tumor suppressor expression was observed in cancer cell
lines treated with ulvan from Enteromorpha intestinalis. The pro-apoptotic activity of
ulvan is also demonstrated by the reduction in expression of anti-apoptotic proteins.