The poisonous mushroom Hypholoma fasciculare (Japanese name: Nigakuritake), belonging to the family Strophariaceae (Basidiomycota, Agaricales), produces fasciculol E as a major toxic agent Fasciculol E has also been reported from a few related species, but the range of species producing it is not clear. In the present study, the content of fasciculol E in fruiting bodies of H. fasciculare and related species in the family Strophariaceae was analyzed by UPLC/MS/MS. The results revealed that all species of Hypholoma examined in this study stably produce fasciculol E. Moreover, a very small amount of the toxin was detected from several species belonging to the genera Pholiota and Stropharia. Of these, some species are known as edible mushrooms, but the amount contained in their fruiting bodies was much lower than the LD50 values of fasciculol E. Phylogenetic analysis using the internal transcribed spacer (ITS) region sequences suggests that the productivity of fasciculol E is correlated with phylogenetic distance from H. fasciculare within the family Strophariaceae.

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Research on natural antioxidants in foods has gained interest in recent years. A wide variety of methods have been used to evaluate antioxidative activity in vitro. However, standardized methods have not yet been established, therefore necessitating the development of novel official methods. We evaluated the scavenging activity of 4 radical species using the electron spin resonance (ESR) spin trapping method and oxygen radical absorbance capacity (ORAC) of the hot water extracts of 13 mushroom species. Moreover, we measured the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of samples. The radical scavenging activity of samples evaluated by ESR did not correlate with the DPPH radical scavenging activity. In order to comprehensively characterize the properties of individual radicals, the radical balance of 6 radical scavenging activities was compared using radar charts. Activity strength was indicated by the area of the radar charts. The radical balance was categorized according to specific radical groups. We propose that antioxidative activity can be evaluated by determining the balance of radical scavenging activity of various mushrooms using radar charts.

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Edible mushrooms are an important source of various nutrients for vegetarians. However, vitamin B_<12> contents of various truffle and shoro fruiting bodies is unknown, and it is also unknown whether they contain vitamin B_<12> or the pseudovitamin B_<12>, which is biologically inactive in humans. We characterized and quantified vitamin B_<12> in the fruiting bodies of black and white truffles (Tuber spp.) and "shoro" (Rhizopogon rubescens) using a microbiological assay based on Lactobacillus delbrueckii subsp. lactis ATCC 7830. Bottled black truffle fruiting bodies contained approximately 4.5 μg of vitamin B_<12> per 100 g of wet weight, but the vitamin B_<12> contents of raw and frozen samples contained approximately 50% or less vitamin B_<12>. In addition, bottled white truffle and shoro fruiting bodies contained approximately 2.9 μg and 3.3 μg of vitamin B_<12> per 100 g of wet weight, respectively. The mean values (approximately 11.5 μg of vitamin B_<12> per 100 g dry weight) of these truffle fruiting bodies were higher than those reported for other edible mushroom fruiting bodies. Corrinoids were purified from the black and white truffles and shoro fruiting bodies and vitamin B_<12> was identified using liquid chromatography-electrospray ionization tandem mass spectrometry.

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Ergosterol peroxide (EP) has been identified as a major lipid in the fruiting bodies of the edible mushroom, Pleurotus cornucopiae; however, EP is only a minor lipid in liquid-cultured mycelia. A glucosylated form of EP (GlcEP) was increased by exposing the filtered mycelia to air, even though EP levels were unchanged. The increase was promoted, by supplying water and/or heat stress at 40℃. Purified EP from the fruiting bodies was subjected to pharmacological testing and was demonstrated to be a stronger inhibitor of the proliferation of the human hematological tumor cell lines, THP-1 and Ramos, than of the human metastatic mammary carcinoma cell line, MCF7.

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We studied the effect of carbohydrates on the growth rate of Termitomyces eurrhizus collected from Okinawa Prefecture, Japan. Four test strains were grown on the base media with the addition of 13 carbohydrates, respectively. These strains showed high catabolism of fructose, mannose, sucrose, maltose and trehalose. Two strains showed relatively high catabolism of soluble starch. However, all strains tended to grow poorly on lactose medium.

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