Mycotoxins in Basidiomycete Mycelium and Fruiting Bodies: Implications for Eu Novel Food Assessment and Selected International Regulatory Frameworks.

Advances in technology have enabled the efficient and sustainable production of basidiomycete vegetative mycelium, particularly from Pleurotus species, as a novel food source. However, mycelium has yet to receive regulatory approval in many global markets, requiring a better understanding of factors affecting its safety. Yet, various studies on different species and mycotoxins suggest that mycelium may be safer than its fruiting body. This review explores the occurrence and distribution of basidiomycete mycotoxins (BMTs) across different species and fungal structures, with a particular focus on Pleurotus spp., given their prominent role in mycelium-based products. BMTs are less studied compared to the well-regulated ascomycete toxins. The authors reviewed all available literature on food‑safety‑relevant BMTs. These include, but are not limited to, amatoxins, coprine, illudins, muscarine, ostreolysin, and psilocybin. The toxins were identified from a resource developed for the European Food Safety Authority's novel food safety assessment. The main finding was that BMTs are predominantly present in the fruiting body rather than in mycelium. Regardless of species or BMT, mycelium showed lower levels compared to the fruiting body. Notably, no mycotoxins exclusive to the mycelium were identified, whereas certain BMTs detected in fruiting bodies were absent in mycelium. This review, the first of its kind, highlights the potential of basidiomycete mycelium as a novel and sustainable food. It also identifies gaps in toxicological data, aiming to inform regulatory bodies and support the development of novel fungal-based foods and materials.