Algal Polysaccharides-Based Hydrogels: Extraction, Synthesis, Characterization, and Applications

Abstract

Hydrogels are three-dimensional crosslinked hydrophilic polymer networks with great potential in drug delivery, tissue engineering, wound dressing, agrochemicals application, food packaging, and cosmetics. However, conventional synthetic polymer hydrogels may be hazardous and have poor biocompatibility and biodegradability. Algal polysaccharides are abundant natural products with biocompatible and biodegradable properties. Polysaccharides and their derivatives also possess unique features such as physicochemical properties, hydrophilicity, mechanical strength, and tunable functionality. As such, algal polysaccharides have been widely exploited as building blocks in the fabrication of polysaccharide-based hydrogels through physical and/or chemical crosslinking. In this review, we discuss the extraction and characterization of polysaccharides derived from algae. This review focuses on recent advances in synthesis and applications of algal polysaccharides-based hydrogels. Additionally, we discuss the techno-economic analyses of chitosan and acrylic acid-based hydrogels, drawing attention to the importance of such analyses for hydrogels. Finally, the future prospects of algal polysaccharides-based hydrogels are outlined.

Recent Advances in the Incorporation of Polysaccharides with Antioxidant and Antibacterial Functions to Preserve the Quality and Shelf Life of Meat Products

“…Polysaccharide content varies depending on the species, ranging from 4% to 76% of the dry weight of the algae. For example, green algae contain lignin, cellulose, and hemicellulose; brown algae contain only cellulose; and red algae are composed of dietary fibers [ 28 ].…”

“…As with polysaccharides from other organisms, different classifications of polysaccharides from macroalgae are encountered in the literature: structural and matrix polysaccharides, anionic and neutral polysaccharides, and sulfated and non-sulfated polysaccharides. Microorganisms and macromycetes are also important sources of natural polysaccharides [ 27 , 28 ].…”

“…As recently reviewed by Lin et al [ 28 ], polysaccharide properties and related polysaccharide-derived hydrogels are deeply affected by purification processes as well as by extraction conditions.…”

“…Recent improvements have focused on the potential applications (in the cosmetic, medical, food, pharmaceutical, and other industries) of these polymers for human use [ 79 , 81 , 82 , 83 ]. The antioxidant and antibacterial activities of Pleurotus eryngii polysaccharides (PEPS) and Streptococcus thermophilus ASCC 1275 exopolysaccharides (ST1275 EPS) were studied by Li and Shah [ 28 ]. The antioxidant activities of this polysaccharide were determined through DPPH, superoxide, and hydroxyl radical scavenging tests and through the FRAP assay.…”

Algal-derived macromolecules and their composites: From synthetic biology to biomedical applications in bone and cardiovascular tissue engineering

“…Algae can form hydrogels, especially from their polysaccharides, through physical crosslinking, defined as noncovalent bonding dependent on weak molecular interactions such as hydrogen bonds, causing reversible gel formation (Lee et al, 2012;Martin and Ballet, 2021). Various polysaccharides can form ideal hydrogels for biomedical applications, including ulvan, starch, agarose, porphyrin, and cellulose (Beaumont et al, 2021;Mandal et al, 2022;Lin et al, 2022).…”