Algal Alginate in Biotechnology: Biosynthesis and Applications

Abstract

Algae are recognized as the main producer of commercial alginate. Alginate produced using algae is located in the walls and intracellular regions of their cells. Its properties vary depending on the species, growing and harvesting seasons, and extraction methods. Alginate has attracted the attention of several industries, thanks to its unique properties such as its biodegradability, biocompatibility, renewability and lack of toxicity features. For example, it is considered a good encapsulation agent due to the transparent nature of the alginate matrices. Also, this biopolymer is recognized as a functional food in the food industry. It can be tolerated easily in human body and has the ability to reduce the risk of chronic diseases. Besides, it is used as an abrasive agent, antioxidant, and thickening and stabilizing agents in cosmetic and pharmaceutic industries. Generally, it is used in emulsion systems and wound dressing patches. Furthermore, this polysaccharide has the potential to be used in green nanotechnologies as a drug delivery vehicle via cell microencapsulation. Moreover, it is suitable to adopt as a coagulant due to its wide range of flocculation dose and high shear stability. In this chapter, the mentioned usage areas of algal alginate are explained in more detail.

Bacterial Alginate Biosynthesis and Metabolism

“…The molecular backbone of alginate, however, was only described decades later, after the work of Fisher and Dörfel in 1955 [3], and the structural analyses of alginate have been an extensive field of research ever since due to the immense variability of M/G content and sequential organization found throughout the years in many macroalgae [4,5]. The structural variability presented by this polymer and the ability to form gels with different physicochemical properties is nowadays reflected in its many biotechnological uses in the food sector, cosmetic industry, wastewater treatment, pharmaceutical, and biomedical applications, among others [6][7][8][9].…”