What Should We Really Be Testing in Functional Mushrooms?
- Alex Sherman
- Jun 2
- 9 min read
Updated: Jun 3
A Meta-Analysis of Industry Gaps, Testing Limitations, and the Case for a Standardized Scientific Future
Despite the explosive growth of the functional mushroom market, most of what we call “standards” are built on shaky ground. While consumer demand has skyrocketed, the foundational science and testing protocols have failed to keep pace. Functional mushrooms hold immense promise—but only if we start treating them with the rigor they deserve. This post is a deep dive into the compounds we should actually be testing for, the problems with the current approaches (including an overreliance on beta-glucans), and a roadmap for how we can move the industry forward from vague labels to verified efficacy.
The Beta-Glucan Illusion
Beta-glucans have become the de facto standard for labeling and validating functional mushroom supplements. The narrative is simple: because beta-glucans are structural components of fungal cell walls, their presence verifies fungal content. But this is a shallow interpretation of a complex biological system. Fungal cells are not uniform across species or strains; their composition—ranging from chitin, glycoproteins, and mannoproteins to ergosterol and cell wall enzymes—varies widely both inter- and intra-specifically.
While 1,3 and 1,6-linked beta-glucans have demonstrated immunomodulatory activity, they represent just one class of polysaccharides. Their structural specificity, source (fruiting body vs. mycelium), and functional role vary—and without identifying these distinctions, “30% beta-glucans” is more marketing shorthand than scientific measure.
Even more critically, beta-glucans are not unique to mushrooms. They’re also found in oats, barley, algae, and even certain bacteria. This becomes a serious issue when mycelium is grown on cereal grain substrates like oats. In these cases, the total beta-glucan content measured in a product may be partially (or significantly) derived from the substrate itself—not the fungus. This skews data and misleads consumers into thinking they’re getting more “functional” content than they actually are.
Yes, beta-glucans like PSP and PSK from Trametes versicolor and Lentinan from Lentinula edodes have been studied and even used clinically. But claiming a generic “beta-glucan percentage” without specificity does nothing to inform consumers of therapeutic potential. The same goes for mycelium biomass vs fruiting bodies. The compounds I will discuss herein vary depending on the part of the fungus they're produced and found. There's no blanket statement to be made about how one part of the mushroom is better than the other, because each species is different and unique, even genotypically.
This post is a deep dive into the compounds we should actually be testing for, the problems with the current approaches (including an overreliance on beta-glucans), and a roadmap for how we can move the industry forward from vague labels to verified efficacy.
Why Standardization Actually Matters
The lack of standardization in the functional mushroom industry undermines trust, efficacy, and scientific legitimacy:
Consumers are left in the dark. They receive little to no information about what they’re consuming beyond vague claims.
Product developers often rely on inherited misinformation or incomplete data propagated for years through unvalidated marketing narratives.
Regulators like the FDA hesitate to grant GRAS status to mushroom extracts due to variability in product composition, a lack of standardized testing, and a rapidly evolving field filled with unverified claims.
As someone who has worked across the value chain—cultivating mushrooms, managing formulation programs, conducting product development, and interfacing with analytical labs—I’ve experienced firsthand the systemic obstacles to reliable testing. Equipment is expensive. Standards are scarce. Sample prep protocols are inconsistent or entirely absent. And perhaps most crucially, many of the compounds we care about—like erinacines, cordycepin, ganoderic acids, or ergothioneine—are volatile, structurally sensitive, and prone to degradation during extraction.
But here’s why standardization matters: without it, we have no baseline for truth. The same sample sent to two different labs can yield dramatically different results—not because one lab is wrong, but because the protocols, equipment, solvents, temperatures, or calibration standards vary. One lab may underreport; another may overreport. And unless both follow a validated method with verified reference materials, there’s no way to know who’s right.
For growers and product developers, this creates logistical and financial risk. For consumers, it breeds misinformation and distrust. For regulators, it stalls recognition of these compounds as GRAS or therapeutically relevant. And for researchers, it creates noise in the data, limiting reproducibility and undermining credibility.
Standardization isn’t just a bureaucratic checkbox. It’s the foundation for efficacy, safety, comparability, and progress. Without shared protocols for extraction, quantification, and reporting, functional mushrooms remain trapped in a marketing-driven cycle, rather than advancing into a therapeutically and scientifically validated category.
The Compounds That Deserve Rigorous Attention
Here’s a comprehensive list of the compounds that must be prioritized for standard development, analytical method validation, and industry-wide integration. This includes species-specific mapping and pharmacological context drawn from decades of research.
Neuroprotective and Nerve Growth Compounds:
Erinacines (A–K, P, Q, S, U) – Found in the mycelium of Hericium erinaceus; stimulate NGF, reduce neuroinflammation, and show strong in vitro/in vivo data for neuroprotection.
Hericenones – Found in fruiting bodies; weaker correlation with NGF expression in humans, though initially promising in murine (mice) studies.
Hericenes – Structural analogues under study; potential synergy with erinacines.
Immunomodulatory Polysaccharides:
PSP & PSK (from Trametes versicolor) – Clinically tested beta-glucan-protein complexes with potent immune-enhancing effects.
D-Fraction (from Grifola frondosa) – Proteoglucan shown to activate NK cells and modulate cytokine release.
Grifolan (from G. frondosa) – Demonstrates T-cell activation and host resistance enhancement.
Lentinan (from Lentinula edodes) – β-1,3:1,6-glucan used in oncology as an immune adjunct.
KS-2 (from T. versicolor) – Another immune-regulating polysaccharide.
Total Beta-glucans – Should include full structural characterization (linkage type, molecular weight, branching).
Anti-inflammatory and Antioxidant Compounds:
Ergothioneine (from Pleurotus, Agaricus) – Potent cytoprotective compound transported by OCTN1; reduces oxidative stress and inflammation.
Glutathione (from Pleurotus eryngii) – Key cellular antioxidant, supports vascular health.
Oxalic Acid – Found in Inonotus obliquus (Chaga); should be quantified to monitor liver stress risk.
Betulin / Betulinic Acid – Found in Chaga and birch bark; antiviral, anti-inflammatory, and anti-tumor activity.
Inotodiol / Inotusic Acid – Unique triterpenoids from Chaga sclerotia with antioxidant and cytotoxic effects.
Ganoderic Acids (A–H) – Found in Ganoderma lingzhi; triterpenes that modulate inflammation, reduce oxidative stress, and potentially support autoimmunity resilience.
Ganoderenic Acids (A–D) – Also in Ganoderma spp.; act on histamine pathways and may downregulate allergic responses.
Lupeol – Pentacyclic triterpenoid with anti-inflammatory properties found in several fungi.
Cardiovascular and Metabolic Compounds:
Lovastatin (Mevinolin, from Pleurotus ostreatus) – Statin compound that inhibits HMG-CoA reductase; reduces LDL cholesterol.
Eritadenine (from Lentinula edodes) – Alters phospholipid metabolism; beneficial for cholesterol reduction.
Pleurotin (from Pleurotus spp.) – Antibiotic and potential antihyperlipidemic compound.
Nucleoside Derivatives and Energy Modulators:
Cordycepin (3’-deoxyadenosine, from Cordyceps militaris, Antrodia camphorata) – Inhibits mTOR, mimics ATP, extends endurance, increase VO2 max, and shows antitumor activity.
Adenosine (from Cordyceps, Ganoderma spp., Flammulina velutipes, Boletus edulis) – Neuroactive and vasodilatory; enhances energy metabolism.
Cordycepic Acid (Mannitol) (from Cordyceps militaris) – Sugar alcohol compound that may help regulate osmotic stress and free radical damage.
Foundational Fungal Metabolites:
Ergosterol / Ergosterol Peroxide – Fungal sterols with immune-modulating and antioxidant properties; precursor to Vitamin D2.
Vitamin D2 (from UV-exposed fungi) – Essential nutrient that can be endogenously converted from ergosterol in fungi.
These last two are important for measuring total fungal content in products, but has one stipulation: ergosterol content varies species-to-species so baseline standards need to be created for each species independently.
Cost and Market Access: The Testing Wall
Analytical Reference Standard Pricing (Selected):
Erinacine A: $809 for 5mg (Centera)
Erinacine P: $4,200 for 1mg (Sigma)
Ganoderic Acid A: $407 for 5mg (Sigma)
These costs make it nearly impossible for most startups or mid-sized labs to engage in robust analytics. The reference materials market is monopolistic, with minimal suppliers producing at scale and virtually no price pressure. This bottleneck stifles industry growth.
Lack of Validated Testing Protocols
Even when a laboratory has access to high-end instrumentation—whether it’s HPLC, LC-MS/MS, GC-MS, or HPTLC—the problem isn’t the tools. The problem is how the tools are used and what they're instructed to detect. Without validated sample preparation protocols, these advanced systems can’t deliver reliable or reproducible results. Analytical outcomes are only as good as the input. And in the world of mushroom testing, the inputs are highly variable:
Is the sample a dried powder, hot water extract, alcohol tincture, or fermented biomass?
Was it grown on grain, wood, or synthetic substrate?
Was it processed fresh or stabilized with heat, solvents, or freeze-drying?
Each matrix has different extraction efficiencies, solubility profiles, and compound retention characteristics. For example, diterpenoids like erinacines and triterpenoids like ganoderic acids may require ethanol or methanol-based extraction, while polysaccharides like PSP or D-fraction are more water-soluble and degrade in alcohol-rich environments. Volatile compounds like erinacines can degrade with temperature, light, or improper pH.
This means that extraction method, solvent polarity, pH, temperature, duration, and filtration method all significantly affect what gets measured—and whether it’s even present in the final analytical output. Adding complexity, many of the most sought-after compounds in functional mushrooms are structurally fragile.
Yet, few if any labs have public, peer-reviewed protocols that clearly define how to preserve, isolate, and quantify these compounds with consistency. And no AOAC or USP-approved methods currently exist for most mushroom-specific metabolites. That leaves labs—no matter how well-intentioned—to invent their own methods, optimize in-house, and operate without a reproducible benchmark. This isn’t science. It’s educated guesswork.
The result? A system where lab-to-lab variation isn’t an exception—it’s the norm. Where human error is inevitable, and industry-wide quality assurance becomes impossible.
If we want to talk about efficacy, safety, or consistency in functional mushrooms, we can’t keep operating like this. Validated, standardized protocols aren’t optional—they’re the prerequisite for moving this field forward.
COA Shopping and Lab-to-Lab Inconsistency
One of the most troubling consequences of poor standardization is the rise of COA shopping—a practice where companies submit the same sample to multiple labs and selectively report the most favorable result. While this behavior is already well-documented (and widely criticized) in the cannabis industry, it is quickly becoming normalized in the functional mushroom space.
Why does this happen? Because in the absence of validated protocols, quantification becomes a function of method, not truth.
Extraction solvents, sample drying methods, matrix preparation, and equipment calibration all play significant roles in the final readout. A sample high in cordycepin might test poorly if extracted with the wrong solvent system or run through an LC-MS lacking sensitivity for nucleosides. Similarly, beta-glucan content can fluctuate based on how well a lab handles the Megazyme kit—if it’s been exposed to light, temperature variation, or improper storage, it could report lower-than-actual values.
In practice, this means a product can yield two different COAs from the same batch, simply because labs are improvising based on available equipment, proprietary methods, or technician interpretation. And without enforced standards, there’s no incentive not to cherry-pick the data that looks best on paper.
This erodes consumer trust, undermines scientific progress, and creates a dangerous illusion of precision. Brands and formulators might believe their product is potent or efficacious based on a flattering COA—but unless it’s been tested against validated, peer-reviewed methods, that data may be more marketing than measurement.
Ultimately, lab-to-lab variability and COA shopping are symptoms of the same problem: we haven’t agreed on what to measure, how to measure it, or how to define quality. Until we do, the industry will continue to operate in a space where truth is subjective—and that’s not a sustainable path forward.
Existing Tests: What's Available Now?
While the majority of mushroom-derived compounds still lack validated testing protocols and commercially accessible standards, a small subset of bioactives are currently testable through established methods or third-party labs. These tests vary in reliability depending on lab capability, technician experience, and access to proper calibration standards—but they offer a starting point. The following compounds have either UPS or AOAC-recognized methods or widely available reference standards that make consistent testing more feasible:
Validated tests and available standards (there are more, but these are the most widely used):
Beta-glucans – Neogen Megazyme AOAC-accredited kit
Cordycepin – Commercially available standard (Sigma)
Erinacine A – Centera standard
Ganoderic Acids A, D – Sigma standards
Betulinic Acid / Betulin – Found in multiple suppliers
Lovastatin – Widely used; synthetic production via yeast
What’s missing? Almost everything else. Most compounds above lack:
Commercial standards
Validated analytical protocols
Inter-lab reproducibility
The Road Forward: Real Solutions
1. Producers Must Act
We need producers—growers, extractors, and suppliers—to put resources behind testing. Talking about transparency without investing in it is performative.
2. Consumer and Brand Advocacy
Consumers and CPG brands alike need to start demanding full COAs. Ask about specific compounds—not just buzzwords. Brands must press suppliers for validated data and commit to education.
3. Expand Research and Open the Conversation
Even if we start testing these compounds today, it will take years to understand dosage, absorption, bioavailability, half-lives, and potential contraindications. We must remain humble and curious.
4. Open-Source Testing Infrastructure
Pooled testing and shared protocol banks can dramatically reduce cost barriers. We should support labs experimenting with shared standards and multi-client validation batches.
5. What I’d Build With Funding
A complete analytical reference library of standards
Validated extraction and prep protocols for each major compound
A central, open-source biorepository for mushroom cultures and ingredients
A non-profit or for-profit lab or academic alliance to anchor and validate these systems
I know how to grow. I know how to extract. If I had the resources, I’d build the infrastructure and share the roadmap. Because it’s time we stop spinning in circles and start setting standards.
Let’s raise the bar—together. If you’re a grower, formulator, researcher, or someone who gives a damn about the future of functional mushrooms, reach out.
Let’s stop selling magic and start building science.
—Spore Growth Partners
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