138
6 Carrageenans
For such application, kappa carrageenan containing seaweed flour is often used in
combination with locust bean. The less refined form of carrageenan costs only a
fraction of the cost of refined carrageenan (one-fourth). Over 5 thousand tonnes of
seaweed powder is used for such applications.
6.7.6 Air Freshener Gels
An estimated 200 tonnes of lower-grade carrageenan in the form of seaweed flour
finds non-food applications as air freshener gels annually (McHugh 2003). The air
freshener perfume is mixed in potassium salt carrageenan and water. The gel is
sealed to prevent evaporation over its storage shelf life. Once opened, the perfume
and water begin to evaporate against the concentration gradient with the environment.
Eventually, the water and perfume completely evaporate and what remains is a hard
dry gel at the end of the product usage life.
6.7.7 Immobilized Cells and Biocatalysts
For different applications such as cell biology or tissue culture preparation, cells need
to be stored in inactive dry forms such that they are protected from the environment
and can also be easily stored, transferred and transported. The ability of kappa carrageenan to form hard gels makes them applicable for such purpose. When required
for use, these immobilized biocatalysts and cells can then be rehydrated and activated.
In one of the early studies on the use of carrageenan for such purpose, the ethanolproducing bacterium Zymomonas mobilis has been entrapped in kappa carrageenan
(Luong 1985). Kappa carrageenan is preferred as it allows immobilization of the
biological component under mild conditions without damage (Chibata et al. 1987).
More recently, enzymes such as cellulase and pollunase have been immobilized using
carrageenan-based polymer complexes (Yasin et al. 2019; Long et al. 2016). Ability
to immobilize cells and enzymes makes more effective processes where the release
and activity of the enzyme can be better managed. Enzyme immobilization is further
discussed in this book in the chapter on Enzymes.
6.7.8 Antimicrobial Properties
Although not its main application, carrageenan extracted from red algae strains
such as H. musciformis has shown antimicrobial activity. Kappa carrageenan from
H. musciformis had antibacterial effect against Staphylococcus aureus and antifungal
effect against Candida albicans (Souza et al. 2018). The carrageenan extracted from
this study had a molecular weight of 519 kDa. Carrageenan molecular weight varies
6 Carrageenans
For such application, kappa carrageenan containing seaweed flour is often used in
combination with locust bean. The less refined form of carrageenan costs only a
fraction of the cost of refined carrageenan (one-fourth). Over 5 thousand tonnes of
seaweed powder is used for such applications.
6.7.6 Air Freshener Gels
An estimated 200 tonnes of lower-grade carrageenan in the form of seaweed flour
finds non-food applications as air freshener gels annually (McHugh 2003). The air
freshener perfume is mixed in potassium salt carrageenan and water. The gel is
sealed to prevent evaporation over its storage shelf life. Once opened, the perfume
and water begin to evaporate against the concentration gradient with the environment.
Eventually, the water and perfume completely evaporate and what remains is a hard
dry gel at the end of the product usage life.
6.7.7 Immobilized Cells and Biocatalysts
For different applications such as cell biology or tissue culture preparation, cells need
to be stored in inactive dry forms such that they are protected from the environment
and can also be easily stored, transferred and transported. The ability of kappa carrageenan to form hard gels makes them applicable for such purpose. When required
for use, these immobilized biocatalysts and cells can then be rehydrated and activated.
In one of the early studies on the use of carrageenan for such purpose, the ethanolproducing bacterium Zymomonas mobilis has been entrapped in kappa carrageenan
(Luong 1985). Kappa carrageenan is preferred as it allows immobilization of the
biological component under mild conditions without damage (Chibata et al. 1987).
More recently, enzymes such as cellulase and pollunase have been immobilized using
carrageenan-based polymer complexes (Yasin et al. 2019; Long et al. 2016). Ability
to immobilize cells and enzymes makes more effective processes where the release
and activity of the enzyme can be better managed. Enzyme immobilization is further
discussed in this book in the chapter on Enzymes.
6.7.8 Antimicrobial Properties
Although not its main application, carrageenan extracted from red algae strains
such as H. musciformis has shown antimicrobial activity. Kappa carrageenan from
H. musciformis had antibacterial effect against Staphylococcus aureus and antifungal
effect against Candida albicans (Souza et al. 2018). The carrageenan extracted from
this study had a molecular weight of 519 kDa. Carrageenan molecular weight varies