We succeeded in isolating and identifying anti-<i>Helicobacter pylori</i> and anti-<i>Campylobacter jejuni</i> compounds from ethyl acetate extract made from <i>Daedalea diknisii</i> culture solution. Anti-H. pylori compounds were identified as (R)-(6-hydroxy-2-methyl-2H-chromene-2-yl)methyl acetate 1, daedalin A 3, and its deoxy analog 2. Compound 1 was isolated for the first time as a natural product. 2,3-Dimethoxybenzene-1,4-diol was also isolated and identified as an anti-<i>H. pylori</i> and anti-<i>C. jejuni</i> compound.

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The aim of this study was to investigate whether specific carbon sources are responsible for bacterial stimulation of mycelial growth of an ectomycorrhizal mushroom, <i>Rhizopogon roseolus</i>, by <i>Paraburkholderia fungorum</i> GIB024, a bacterium isolated from the sporocarp of <i>R. roseolus</i> located in a <i>Pinus thunbergii</i> forest. We designed a two-compartment media in a non-separated Petri dish for a direct confrontation bioassay. The first compartment for growing the fungus was filled with 1 : 5 diluted MMN without glucose. The second compartment acted as the bacterial medium and was filled with various sole carbon sources, which were grouped into free sugars, sugar alcohols, organic acids, malt and yeast extract, soluble starch, chitin, and no addition of a carbon source. <i>R. roseolus</i> growth was stimulated when <i>P. fungorum</i> was grown in the organic acids rather than in other carbon source groups. Moreover, the bacterium grew better in organic acids than in free sugars or sugar alcohols. In the organic acid supplemented-medium, the bacterium increased the environmental pH and its sterilized suspension stimulated growth of <i>R. roseolus</i>. These results suggested a potential role of organic acids as a mediator during the mutual interaction betwe

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Edible mushrooms, especially <i>Fistulina hepatica</i>, contain substantial concentrations of l-ascorbate (vitamin C; AsA). In this study, we determined AsA in cultivated <i>F. hepatica</i> fruiting bodies using an official AsA assay method from the Standard Tables of Food Composition in Japan. Additionally, we used gas chromatography-mass spectrometry (GC-MS) to clarify whether the fruiting bodies of <i>F. hepatica</i> contain AsA that can function as a vitamin in humans. A considerable amount of AsA (approximately 406 mg/100 g dry weight) was detected in cultivated <i>F. hepatica</i> fruiting bodies using the official method from the Standard Tables of Food Composition in Japan. Additionally, while two fungus ascorbate analogs, 6-deoxyascorbate and erythroascorbate, were detected by GC-MS, AsA was absent.

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