Diversity of Sulfated Polysaccharides From Cell Walls of Coenocytic Green Algae and Their Structural Relationships in View of Green Algal Evolution

Abstract

Seaweeds biosynthesize sulfated polysaccharides as key components of their cell walls. These polysaccharides are potentially interesting as biologically active compounds. Green macroalgae of the class Ulvophyceae comprise sulfated polysaccharides with great structural differences regarding the monosaccharide constituents, linearity of their backbones, and presence of other acidic substituents in their structure, including uronic acid residues and pyruvic acid. These structures have been thoroughly studied in the Ulvales and Ulotrichales, but only more recently have they been investigated with some detail in ulvophytes with giant multinucleate (coenocytic) cells, including the siphonous Bryopsidales and Dasycladales, and the siphonocladous Cladophorales. An early classification of these structurally heterogeneous polysaccharides was based on the presence of uronic acid residues in these molecules. In agreement with this classification based on chemical structures, sulfated polysaccharides of the orders Bryopsidales and Cladophorales fall in the same group, in which this acidic component is absent, or only present in very low quantities. The cell walls of Dasycladales have been less studied, and it remains unclear if they comprise sulfated polysaccharides of both types. Although in the Bryopsidales and Cladophorales the most important sulfated polysaccharides are arabinans and galactans (or arabinogalactans), their major structures are very different. The Bryopsidales produce sulfated pyruvylated 3-linked β- d -galactans, in most cases, with ramifications on C6. For some species, linear sulfated pyranosic β- l -arabinans have been described. In the Cladophorales, also sulfated pyranosic β- l -arabinans have been found, but 4-linked and highly substituted with side chains. These differences are consistent with recent molecular phylogenetic analyses, which indicate that the Bryopsidales and Cladophorales are distantly related. In addition, some of the Bryopsidales also biosynthesize other sulfated polysaccharides, i.e., sulfated mannans and sulfated rhamnans. The presence of sulfate groups as a distinctive characteristic of these biopolymers has been related to their adaptation to the marine environment. However, it has been shown that some freshwater algae from the Cladophorales also produce sulfated polysaccharides. In this review, structures of sulfated polysaccharides from bryopsidalean, dasycladalean, and cladophoralean green algae studied until now are described and analyzed based on current phylogenetic understanding, with the aim of unveiling the important knowledge gaps that still exist.

Extraction Procedure, Characteristics, and Feasibility of Caulerpa microphysa (Chlorophyta) Polysaccharide Extract as a Cosmetic Ingredient

“…Previous studies have been summarized reported that the glycosidic bonds of Caulerpa genus including 4-Linked xylose, 6-linked galactose, 4-linked mannose, 6-linked α-D-mannopyranose, and 4-linked and 2-linked α-D-mannopyranose [ 30 ]. However, due to the information on the structure of the polysaccharides are not enough, the critical mechanism and function are not clarified [ 31 ]. Our result found the most monosaccharide in C. microphysa was mannose and followed were glucose and galatose.…”

Chemical Structure and Anticoagulant Property of a Novel Sulfated Polysaccharide from the Green Alga Cladophora oligoclada

“…Based on the analysis of 1 H- 13 Moreover, the anomeric proton signal of G was correlated to the H-6 of A, B, E, and F in 1 H-1 H NOESY spectrum; thus, the fragments were confirmed as →6)-β-D-Galp-(1→6)-α- So far, the structure characteristics of polysaccharides from the genus Cladophora were seldom reported. The polysaccharide from C. rupestris had a highly branched structure with galactose, arabinose, and rhamnose residues in the main chain and xylose and galactose at the side chains [22]. Subsequently, a polysaccharide from C. socialis was reported, it mainly consisted of 4-linked arabinose and 3-linked galactose [23].…”

Polysaccharides and Derivatives from Africa to Address and Advance Sustainable Development and Economic Growth in the Next Decade

“…Green algae [37] Ulvan Repeating disaccharide ulvanobiouronic acid with Xyl, Glc, Rha, and sulfate groups Green algae [38] Xylan β-(1,3)-xylan Green algae [15] Today, tool-assisted extractions (including the use of enzymes) are a classic for obtaining biomolecules (including carbohydrates), such as microwaves, high-pressure systems, or ultrasounds. It results in extracting polysaccharides faster, at lower-water temperatures while conserving the polymer structural features [39].…”

“…Oligo-and polysaccharides have many biological and pharmacological activities such as immunomodulatory, immuno-restorative, immunoregulatory, anti-inflammatory, antibacterial, antioxidant, antiviral, etc. [1,4,6,11,[18][19][20][21][22]25,30,[34][35][36][37][38][40][41][42][43]63]. Thus, numerous reports on the biological activity of polysaccharides extracted from plants and used in traditional medicines have been published.…”