Journal
Coriolus extract: what 10:1 means, PSK, PSP, and how to read the label
DER 10:1, standardization to beta-glucans, the PSK and PSP fractions. We break down a coriolus extract label point by point, before you buy.
TCM therapist · Doctor of Acupuncture (WFAS) · author of a book on functional mushrooms
5 min read

Contents
You're buying a coriolus extract and the label says "10:1" and "min. 30% beta-glucans", alongside the abbreviations PSK and PSP, but nobody has explained what those letters and numbers actually tell you about what's in the package. This post breaks down the coriolus label into four questions worth asking before you buy, and shows what they look like in practice on our own raw material.
What is coriolus extract, and how is it different from fruiting-body powder?
Coriolus extract is a concentrated form of the fruiting body, with part of the inactive mass (fiber, water) removed, leaving the active compounds behind. Plain dried fruiting-body powder contains the same compounds, but at the dilution natural to the raw material, without a concentration step.
The difference is practical, not marketing. Powdered coriolus fruiting body is the whole, ground mushroom, with everything in it, including mass your body can't digest. Extract is the result of a process that pulls out and concentrates the active fraction from the same amount of raw material. That's why our LONGEVITY line blends both forms in equal parts (50% 10:1 extract and 50% powdered fruiting body), while our PRIME line shifts the ratio toward extract (80% to 20%), so you can choose the intensity.
What does 10:1 (DER) mean?
DER, or drug-extract ratio, is the proportion of raw material used to produce one unit of finished extract. At DER 10:1, the producer uses 10 kilograms of dried coriolus fruiting body to get 1 kilogram of extract, a tenfold concentration relative to the starting material.
The DER number alone says nothing about where the fruiting body comes from, so it's always worth checking the raw material source. Our 10:1 extract comes from mature Trametes versicolor fruiting bodies, never from mycelium grown on rice or oats, which matters for the ratio of compounds we cover below.
What are PSK, PSP, and beta-glucans?
With coriolus, researchers focus on two groups of molecules. The first is polysaccharide-peptides, complex structures where a sugar chain is bonded to a peptide portion. In the literature they're described mainly as PSK, also known as krestin, and PSP. The second group is beta-glucans, polysaccharides with a characteristic chain and branching structure, present in the fruiting body's cell wall.
Our 10:1 extract is standardized to a minimum of 30% beta-glucans. We describe PSK and PSP as present in the extract fraction, without stating a separate standardization percentage for them, since beta-glucans are the number our label specification is built on. In practice, in a daily serving of 3 capsules (0.5 g extract each, 1.5 g total), a minimum of 450 mg is beta-glucans. That's a concrete number on the label, not a vague "rich in polysaccharides" claim.
Fruiting body vs. mycelium on grain?
Many cheaper coriolus products are mycelium grown on rice or oats, with a high starch content from the grain substrate, easily mistaken for the weight of the mushroom itself on the label.
We work exclusively with the fruiting body, never mycelium, because it's the fruiting body, not the growing substrate, that carries the documented PSK, PSP, and beta-glucan fractions. Producers selling grain-grown mycelium biomass can list a high "extract" weight on the label, even though much of it is starch from the substrate, not compounds from the mushroom itself.
How to read a coriolus label in 5 points
Before you buy a coriolus extract, check five specific things on the label, rather than going by brand name or price per package alone. Each of these points gives you a different piece of the picture.
- Fruiting body vs. mycelium on grain · fruiting body is the hard, fan-shaped part of the mushroom known from tradition; mycelium on rice or oats is a cheaper cultivation substrate with a high starch content.
- DER (extraction ratio) · e.g. 10:1, tells you about concentration, not raw material quality.
- Beta-glucan standardization · a percentage without a clearly stated minimum is hard to verify.
- Milligrams per serving, not just percentage · a percentage in the extract is not the same as the real amount in a daily capsule, scoop, or drop.
- Batch testing · does the producer test every batch at an independent, accredited laboratory for heavy metals and pesticide residues.
In our case, every batch goes to the independent, accredited Eurofins laboratory before a package leaves the warehouse.
Frequently asked questions about coriolus extract
Does a higher DER always mean a better product? Not automatically. A higher DER tells you about weight-based concentration, not the content of specific compounds. A 4:1 extract standardized to a high beta-glucan percentage can realistically contain more per serving than a non-standardized 15:1 extract. Always look at both parameters together.
How is PSK different from PSP? Both names describe coriolus polysaccharide-peptides, complex molecules that combine a sugar chain with a peptide portion. PSK is also known as krestin. The literature distinguishes them by isolation method and strain origin, but both are among the best-documented fractions of this species.
Why are some coriolus extracts cheaper despite a similar DER? Most often because they use mycelium on rice or oats instead of fruiting body, or don't test every batch at an independent laboratory. These choices lower production cost, but they also change the composition of the final product.
Does the label always state beta-glucan standardization? Not always, and that's a warning sign. A percentage without a clearly stated minimum is hard to verify and compare across products from different producers.
For more on choosing between coriolus forms in practice, see our post on capsules, powder, and drops, and for dosage in concrete numbers see coriolus dosage. We cover the species' tradition and appearance in coriolus, turkey tail, and how to read extract labels in general in how to read an extract label.
This content is for educational purposes only and does not constitute medical advice. A food supplement does not replace a varied diet or a healthy lifestyle. If in doubt, consult your doctor or pharmacist.