Beta-Glucans

Beta-glucans are a family of polysaccharides, long chains of glucose sugar molecules, that form part of the cell walls of fungi, yeast, algae and cereal grains such as oats and barley. In the world of functional mushrooms, they are one of the most talked-about natural compounds.

Mushroom beta-glucans vs. grain beta-glucans

The "beta" refers to the way the glucose units are linked. Mushroom and yeast beta-glucans mostly have a backbone of beta-1,3 links with side branches at the beta-1,6 position. Oat and barley beta-glucans use a mix of beta-1,3 and beta-1,4 links instead. These structural differences are why scientists study the two groups separately.

Where they are found in mushrooms

Beta-glucans are woven together with chitin in fungal cell walls. Because chitin is tough, simmering is used to release them, which is why teas and hot-water extraction have long been the traditional preparation for woody species like reishi and turkey tail. Well-known named beta-glucans include lentinan from shiitake and the "D-fraction" from maitake.

Research

Mushroom beta-glucans have been the subject of a large body of laboratory and human research over several decades, especially in Japan, China and Korea. The findings depend on the source species, the structure of the molecule and how it was prepared, and scientists continue to study them.

How beta-glucans are measured

• Labs often use enzyme-based tests that separate beta-glucans from alpha-glucans (starches).
• This distinction matters because a general "polysaccharide" figure can include starch from grain in mycelium-based products.
• A certificate of analysis from an independent lab is the usual place such results appear.

Why it matters to you

Understanding beta-glucans helps you read mushroom labels with a critical eye. Polkadot confections are made with a functional, adaptogenic mushroom blend and are enjoyed first and foremost as gourmet chocolate, gummies, truffles and shots. Explore the idea in What Is Functional Mushroom Chocolate?