Indole compounds in fruiting bodies of some edible Basidiomycota species

The contents of nonhallucinogenic indole compounds were determined in methanol extracts from fruiting bodies of four common edible European species of higher fungi representing the most popular taxon Basidiomycota: Agaricus bisporus (J.E. Lange), Cantharellus cibarius Fr., Lactarius deliciosus (L. Fr.) S.F. Gray and Leccinum rufum (Schaef.) Kreisel. Amongst eleven compounds under analysis, 6–7 metabolites, distinct in different species, were identified in the extracts of fruiting bodies. Serotonin and melatonin were the only common compounds to all species. The contents of the analyzed compounds were diverse, ranging from 0.01 to almost 40 mg/100 g d.w. The contents of tryptophan, 5-hydroxytryptophan, tryptamine and melatonin were low (below 1.40 mg/100 g d.w.). Noteworthy, the serotonin contents were very high in all species under study and amounted to 5.21, 29.61, 18.42 and 31.71 mg/100 g d.w., respectively. Moreover, the fruiting bodies of these species contained indoleacetic acid (max. 2.04 mg/100 g d.w.) and tryptophan degradation products: kynureine sulfate (max. 39.20 mg/100 g d.w.) and kynurenic acid (6.21 mg/100 g d.w.).