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Polysaccharides from Marine Micro- and Macro-Organisms
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Kannan Kamala, Pitchiah Sivaperumal, Gopal Dharani
The galactan family of sulfate polysaccharide consists of an ester sulfate group at 15–40% and replaces the unit of anhydro-galactose, D-galactose, with α and β glycosidic linkages dictated by the activity of carrageenan, and it is isolated into three forms which are iota (ι), kappa (κ), and lambda (λ) composed with a sulfate group on galactose (Necas and Bartosikova, 2013; Knutsen et al., 1994; Silva et al., 2010; Usov, 1998). The carrageenan viscosity with water forms the gel without temperature which extracted from the rhophytes from the Atlantic Ocean (Gates, 2014; Hernandez-Ledesma and Herrero, 2014). It is used for the activity of lipid reduction, a cough remedy, blood coagulation, food processing, atherosclerosis, and pharmaceutical applications (Necas and Bartosikova, 2013). It has shown atherosclerotic development in rats, also lowering the level of lipid, phospholipids, and cholesterol in rabbits (Murata, 1961, 1962; Ito and Tsuchiya, 1972). In addition, triglyceride and serum cholesterol were reduced in humans at 8 weeks (Sokolova et al., 2014). Furthermore, carrageenan has been used for its antithrombin and anticoagulation activity (Kindness et al., 1979, 1980; McMillan et al., 1979; Guven et al., 2009; Silva et al., 2010).
Molecular modification of marine sulfated polysaccharides
Published in Antonio Trincone, Enzymatic Technologies for Marine Polysaccharides, 2019
Sutapa Biswas Majee, Dhruti Avlani, Gopa Roy Biswas
In the age of glycomics, sulfated fucans and sulfated galactans constitute the most widely studied class of marine sulfated polysaccharides or nonglycosaminoglycans (Arata et al. 2016). Fucose-rich sulfated polysaccharides or sulfated fucans are classified into three categories: fucosylated chondroitin sulfate from sea cucumbers, fucan sulfates from sea urchins, and fucoidans from brown seaweeds (Phaeophyceae). They show promise as heparin substitutes in control of thrombus and emboli formation and effectively inhibit angiogenesis, P- and L-selectin-mediated inflammation, and microbial and viral adhesion to host cells (Ustyuzhanina et al. 2006; Kryloy et al. 2011; Ustyuzhanina et al. 2016). They are able to mimic carbohydrate ligands of natural receptors. Sulfated galactans are abundant in green (Chlorophyceae) and red seaweeds (Rhodophyceae). Green algae have been classified into different groups depending on the diverse structural composition of the sulfated polysaccharides, such as glucuronoxylorhamnans, glucuronoxylorhamnogalactans, and xyloarabinogalactans (Silva et al. 2012).
Biodegradation of Hemicelluloses
Published in Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel, Hemicelluloses and Lignin in Biorefineries, 2017
Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel
Arabinans, galactans, and arabinogalactans (Figure 5.1) constitute together the so-called neutral pectic substances.150 Pure arabinans and galactans occur in plant cell walls but are relatively rare. Pure arabinans are typically composed of α-1,5-arabinosyl residues which are decorated with α-1,2- and α-1,3-arabinosyl units. Pure galactans consist mainly of β-1,4-linear polymers. Arabinogalactans are branched polysaccharides which fall into two groups, namely arabinogalactans type I and arabinogalactans type II. The important structural difference between these two types of arabinogalactans is the galactose units, which are 1,4-linked in type I and 1,3- and 1,6-linked in type II.151 The backbone of arabinogalactans type I is composed of β-1,4-linked galactosyl residues, bearing 20%–40% of α-arabinosyl residues 1,5-linked in short chains, in general at position 3.152 The backbone of arabinogalactans type II is composed of β-1,3-linked galactosyl residues, which are substituted at position 6 with β-1,6-linked galactosyl residues and α-1,3-linked-arabinosyl or arabinans sidechains.153
Isolation of active coagulant protein from the seeds of Strychnos potatorum – a potential water treatment agent
Published in Environmental Technology, 2018
P. Arunkumar, V. Sadish Kumar, S. Saran, Harsha Bindun, Suja P. Devipriya
The primary objective of this study is to determine the inherent coagulation mechanism with respect to these seeds. So far, the seeds of S. potatorum were reported to possess macromolecules such as lipids, alkaloids and polysaccharides consisting of –COOH and free–OH radicals enhancing the coagulation efficacy of the seed extract. However, the reports of Adinolfi et al. [18] suggest that the seed extracts containing polysaccharide moiety of galactan and galactomannan mixture exhibited coagulation activity up to 80% in kaolinite synthetic turbid solution. The galactomannan containing 1,4-linked β-D-mannopyranosol residues consist of numerous free –OH groups along the mannose backbone instigating the inter-particle bridging by means of the coagulation mechanism [19]. But in case of all the other plant coagulants, the inherent coagulant fraction involved in the coagulation mechanism is mostly reported as protein moiety of positively charged peptides [20] Henceforth, the detailed coagulation mechanism reported so far with the S. potatorum is deemed to be polysaccharide-induced coagulation mechanism [19].