Mushroom volatiles – diversity, synthesis, function, and applications

Mushrooms produce a wide variety of volatile organic compounds. The most prominent groups are C8 compounds, terpenes and sulphur containing volatiles. C8 volatiles, especially oct-1-en-3-ol, are ubiquitous among mushroom species and responsible for the typical “mushroomy” odour. Terpenes are a much larger and, both, structurally and olfactorily more diverse group, exhibiting for example citrus, herbal or woody odour impressions. Sulphur containing volatiles are known for their pungent smell and are responsible for the characteristic aroma of e.g. shiitake and truffles. In case these volatile organic compounds can be perceived by the human nose, they can be specified as aroma compounds. No matter whether they are aroma active or not, they have several biological functions. Volatiles can act as intraspecies or interspecies signalling molecules e.g., they can attract pollinators or repelling pathogens. Possible applications of volatile organic compounds include their usage in the food and flavour industry as well as pharmaceutical and fragrance applications. Fungal volatiles have also shown antifungal, antibacterial or insecticidal effects that can be exploited in future applications. This chapter gives a brief summary of the diverse world of mushroom volatiles, their synthesis, functions and applications.