Beta-glucans are a kind of polysaccharides which are very common in nature. They are formed by the linkage of thousands of sugars, one after another and branched too, giving rise to huge structures. The ones present in many mushrooms like reishi, have the ability to modulate the immune system and thus they are considered to have antitumor and anticancer virtues, among others.
Beta-glucans contained in oat decrease blood cholesterol.
The amount of beta glucans present in a product, itself, does not speak about its properties. For example: over 99% of the content of paper towel rolls are beta glucans.
So, what is important regarding beta-glucans? For reishi mushrooms and other mushrooms, the important beta-glucans are those with immunological action, that is, those that get linked by 1-> 3, 1-> 6 linkage, and the most active within this group are those that show triple helix conformation, very similar to how DNA is coiled.
Picture of a 1-3 and 1-6 beta glucan. Thousands of these units form a polysaccharide of beta-glucan type.
It is considered that the triple helix structure present in the beta-glucans of fungi is the one that interacts on cell receptors, leading to an immune response in the body: it is like a key that when turning activates the mechanism.
In the market, it is common to find reishi extracts which indicate the amount of beta-glucans they contain, but what industries do not know is that the beta-glucans of reishi deteriorate during the extraction process: their triple helix conformation is lost by the action of the most common extractants. Losing this spatial conformation means losing much of their activity: it is like bending the key used to go into a house and then try to open the door with it, it does not work.
Today, the only safe way to consume intact beta-glucans is consume them in well processed pure reishi.
Thus, the amount of beta glucans of a product is not a datum that serves to compare the quality between a reishi or reishi extract and another. The type of beta-glucans that it possesses is the relevant thing: if they have many triple helices and if those are damaged or not. In addition, the mulecular weight of the beta-glucan, its branches, if it’s linked to other molecules such as proteins or peptides… also affects its properties... but that's for another post.
And finally, in pure reishi, does processing influence the quality of the beta-glucans and other polysaccharides? Really a lot! Recent research shows that there may be a difference up to 30% in antioxidant power between a reishi dried with one or another technique. And no one has studied the grinding process, which is usually much more aggressive (and probably has more influence on it). What’s more, if we add to this that the polysaccharides of reishi and their activity vary depending on the strain of the cultivated reishi, the food that feeds the fungus or the temperature at which it develops, in the end one gets to understand why there is such a big difference in quality between a good pure reishi and another.