Table 2.

Potential synergistic effects of treating SARS-CoV-2 infection with SP.

Activity	S-Polysaccharides	Origin	Proposed mechanisms of action	Current state	References
Immunomodulation	Acidic sulfated polysaccharides, carrageenans, dextran sulfate, fucoidan, and fucans, Sulfated mannan	Ulva rigida, Porphyra yezoensis, Laminaria, Gelidum, Ganoderma lucidum Nemalion helmintoides	Increase the activity and viability of macrophages	In vitro assays and/or regular diet components	[36,56]; J. [88]; S.-Y [70].
Antioxidant	Fucoidans Gluco-manno-xylo-galactans	Padina boryana Caulerpa cupressoides Gracilaria fisheri	ROS scavenging, hydrogen-radicals interaction, reduction of lipid peroxidation, catalase activity enhancement.	Research in cell cultures; used in traditional Chinese medicine	[51,57,59]; J [70,88].
Antitumor (cancer growth arrest)	Fucoidan, carrageenans, agarans	Fucus evanescens Eisenia bicyclis	Stimulation of phagocytic activities of macrophages and neutrophils; cancer cells' apoptosis	Used as functional foods	[70,82,86,89]
Anticoagulant	Sulfated ulvan, glycose amino glycans (heparin sulfate, dermatan sulfate, heparan sulfate), fucans.	Animal cells, Ulva rigida Monostroma angicava, M. oxysperma, Penicillus captatis, Codium divaricatum, Enteromorpha linz, Holoturia fuscopunctata	Inhibition of antithrombin complexes, Xase inhibition	Routine pharmacologic application (heparin), and experimental approaches	[28,65,66,90,91]
Antibacterial	fucoidan	Cuttlefish, Smooth hound, Malva aegyptiaca, Sargassum polycystum	Damage to the bacterial membrane	Research	[52,72,73,92]
Anti SARS-CoV-2	Unfractionated Heparin UFH, Low molecular weight heparins (LMWHs), heparan sulfate proteoglycans, fucoidans, TriS-heparin. Sea cucumber SP, fucoidans, carrageenan and chondroitin sulfate	Seaweeds, biologically and chemically engineered polysaccharides. Sea cucumber, shark	Molecular docking, leading to a conformational change of S protein that blocks viral attachment and infection. Multivalent interactions	Research	[1,15,18,25,32,93]