Overview on biological activities and molecular characteristics of sulfated polysaccharides from marine green algae in recent years

Abstract

Among the three main divisions of marine macroalgae (Chlorophyta, Phaeophyta and Rhodophyta), marine green algae are valuable sources of structurally diverse bioactive compounds and remain largely unexploited in nutraceutical and pharmaceutical areas. Recently, a great deal of interest has been developed to isolate novel sulfated polysaccharides (SPs) from marine green algae because of their numerous health beneficial effects. Green seaweeds are known to synthesize large quantities of SPs and are well established sources of these particularly interesting molecules such as ulvans from Ulva and Enteromorpha, sulfated rhamnans from Monostroma, sulfated arabinogalactans from Codium, sulfated galacotans from Caulerpa, and some special sulfated mannans from different species. These SPs exhibit many beneficial biological activities such as anticoagulant, antiviral, antioxidative, antitumor, immunomodulating, antihyperlipidemic and antihepatotoxic activities. Therefore, marine algae derived SPs have great potential for further development as healthy food and medical products. The present review focuses on SPs derived from marine green algae and presents an overview of the recent progress of determinations of their structural types and biological activities, especially their potential health benefits.

Figure 1

The pie chart of green seaweeds in genus category used as raw materials to prepare sulfated polysaccharides (SPs) (data were calculated from the available references).

Figure 2

The morphology of some representative species of green seaweed in living.

Figure 3

Structure of some main repeating unit sequences found in ulvan.

Figure 4

Some possible structural unit sequences found in galactans biosynthesized by Codium seaweeds.

Figure 5

The main backbone structures of some typical sulfated mannans isolated from green seaweeds. (a) common mannan; (b) sulfated mannan from Codium vermilara; (c) sulfated mannan from Codium fragile; (d) sulfated mannan from Capsosiphon fulvescens.