Rhamnan Sulfate (RS) is a compound extracted from a green algae that grows of the Southwest coast of Japan. This algae is called Monostroma nitidum. Now this extract (Rhamnan sulfate) seems like a jack of all trades. In multiple different research studies it has been found to have antiviral, anti tumoral, anti thrombotic, anti hypercholesterolemia, antihyperglycemia, and anti obesity effects. This is truely a multi-purpose compound.
For our purposes I will focus on the cardiovascular relevant actions of supporting the vascular lining (the "endothelial glycocalix"), and the anti-thrombotic (clot dissolving) properties. Rhamnan sulfate strongly inhibited clot formation under several different experimental conditions. RS also showed significant ability to support normal endothelial function and decrease or prevent endothelial inflammation. Endothelial inflammation is a necessary component of clot formation in most cases. At least part of the antithrombotic activity of RS involves its ability to support and activate our own antithrombin (1)(4). In additional research "Rhamnan sulfate has beneficial effects in reducing inflammation, binding growth factors and NF-κB, enhancing endothelial barrier function and reducing atherosclerotic plaque formation..." (2)
When compared to the anticlotting drug Heparin, RS was significantly more capable of decreasing endothelial inflammation through multiple mechanisms (1).
A long quote from the article cited below: "M. nitidum RS has a wide range of health-promotion effects in lifestyle-related disorders—it prevents obesity and the elevation of LDL cholesterol and suppresses the elevation of blood glucose levels. It was also shown to improve various vascular dysfunctions caused by lifestyle-related diseases. In addition to the health-promoting effects of lifestyle-related disorders, RS may be important in combating viral epidemics." (1)
Rhamnan sulfate has also shown promise as an antiviral with specific action against the spike protein binding site for Cov id 19 (3). This may be (not proven yet) beneficial for those who recently received their shot or booster and want to minimize any potential damage from the spike protein.