9
sweetener in foodstuffs (Johnson et al. 2017). Many studies show the use of glycerol
as a thickening agent in any beverages. Since the nutritional profile of glycerol suggests that it contains low glycemic index, its use as an alternative to table sugars is
preferred more (Balder 2018).
1.3.3 Fungal Chitosan
Chitosan is made up of many acetylated and deacetylated saccharide units. This
component is present in the outer cell walls of the fungi and is known to impart
rigidity to fungal cells. The other sources where chitosan can be extracted are from
crustaceans, some filamentous fungi, yeasts, and algal sources. However, extraction
of chitosan from crustaceans has many side effects such as the incorporation of
allergic proteins along with chitosan, the availability of the sources, the regulatory
affairs, and many more. Hence, the production of this component has been made
possible from the fungal and algal sources. Fungal sources are usually considered
for the extraction. As it is the major element of fungal cell walls, for its production,
the fungal cells are cultivated, and later on, chitosan is harvested using some particular enzymes. It has been seen that for cultivation of fungal colonies, many cheap
substrates are being used, especially the biowastes from the agro-based industries.
This alternative is cheap and results in unlimited production of fungal species. One
particular study demonstrates the use of popular enzyme – α-amylases – in order to
harvest the chitosan from fungal cell walls. The use of this enzyme resulted in the
higher yield of chitosan as compared to regular extraction processes (Ghormade
et al. 2017). The study conducted by Tajdini and others in 2010 showed that chitosan could be extracted from the fungal mycelium too. During the study, spore suspensions from two fungal species Rhizomucor miehei and Mucor racemosus were
used, and the applied culture conditions were continued till the particular amount of
fungal mycelia is formed. It is followed by the separation of chitosan from mycelia
by filtration and washing procedures. Then the pH was adjusted to neutral and purification along with deacetylation of extracted chitosan was performed. Another
study also demonstrated the use of different fermentation procedures for chitosan
production. In this study, the researchers have checked the maximum chitosan production by using both submerged and solid state fermentation with different nitrogen sources. It was concluded that urea was examined as the best nitrogen source
during the fermentation process (Nwe et al. 2011). It was concluded from this study
that submerged fermentation was able to produce more fungal biomass as well as
fungal chitosan. The molecular weight of the harvested chitosan was also determined using the gel permeation chromatographic techniques, and it was further
concluded that solid state fermentation is considered only for the extraction of lower
molecular weight chitosan elements (Zhao et al. 2011). Moreover, another study
states that cheap and effective production of chitosan could be made possible by just
maintaining low pH and temperature conditions under unsterile conditions. All the
culture media and physical parameters were optimized and validated during this
1 Fungal Byproducts in Food Technology
sweetener in foodstuffs (Johnson et al. 2017). Many studies show the use of glycerol
as a thickening agent in any beverages. Since the nutritional profile of glycerol suggests that it contains low glycemic index, its use as an alternative to table sugars is
preferred more (Balder 2018).
1.3.3 Fungal Chitosan
Chitosan is made up of many acetylated and deacetylated saccharide units. This
component is present in the outer cell walls of the fungi and is known to impart
rigidity to fungal cells. The other sources where chitosan can be extracted are from
crustaceans, some filamentous fungi, yeasts, and algal sources. However, extraction
of chitosan from crustaceans has many side effects such as the incorporation of
allergic proteins along with chitosan, the availability of the sources, the regulatory
affairs, and many more. Hence, the production of this component has been made
possible from the fungal and algal sources. Fungal sources are usually considered
for the extraction. As it is the major element of fungal cell walls, for its production,
the fungal cells are cultivated, and later on, chitosan is harvested using some particular enzymes. It has been seen that for cultivation of fungal colonies, many cheap
substrates are being used, especially the biowastes from the agro-based industries.
This alternative is cheap and results in unlimited production of fungal species. One
particular study demonstrates the use of popular enzyme – α-amylases – in order to
harvest the chitosan from fungal cell walls. The use of this enzyme resulted in the
higher yield of chitosan as compared to regular extraction processes (Ghormade
et al. 2017). The study conducted by Tajdini and others in 2010 showed that chitosan could be extracted from the fungal mycelium too. During the study, spore suspensions from two fungal species Rhizomucor miehei and Mucor racemosus were
used, and the applied culture conditions were continued till the particular amount of
fungal mycelia is formed. It is followed by the separation of chitosan from mycelia
by filtration and washing procedures. Then the pH was adjusted to neutral and purification along with deacetylation of extracted chitosan was performed. Another
study also demonstrated the use of different fermentation procedures for chitosan
production. In this study, the researchers have checked the maximum chitosan production by using both submerged and solid state fermentation with different nitrogen sources. It was concluded that urea was examined as the best nitrogen source
during the fermentation process (Nwe et al. 2011). It was concluded from this study
that submerged fermentation was able to produce more fungal biomass as well as
fungal chitosan. The molecular weight of the harvested chitosan was also determined using the gel permeation chromatographic techniques, and it was further
concluded that solid state fermentation is considered only for the extraction of lower
molecular weight chitosan elements (Zhao et al. 2011). Moreover, another study
states that cheap and effective production of chitosan could be made possible by just
maintaining low pH and temperature conditions under unsterile conditions. All the
culture media and physical parameters were optimized and validated during this
1 Fungal Byproducts in Food Technology