Low-molecular polyamines with high alkalinity interact with the acidic polymers of nucleic acids (DNA and RNA), potentially serving as a factor in the origin of life within the cells of all organisms. We have developed a method for the simultaneous analysis of approximately 40 kids of polyamines in the acid extract from cells using high-performance liquid chromatography and high-performance gas chromatography. Comprehensive polyamine analyses of the 5 groups of the kingdom Fungi (mushrooms, molds, filamentous fungi, yeasts, and microsporidia) were carried out as a part of the polyamine analyses of all groups of organisms. In No.1, the structure, biosynthesis, metabolism, and resolution of cellular polyamines are described.

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In this study, we produced wine using Lepista nuda, and the production of alcohol, changes in organic acids, and the behavior of alcohol dehydrogenase (ADH) during the fermentation period were investigated. Furthermore, the ADHs involved in ethanol (EtOH) production using L. nuda were purified by molecular weight cut-off and then examined for their specific activity in the production of other alcohols such as methanol and butanol. EtOH production in wine using L. nuda peaked during the first and second weeks of fermentation. The wine made with L. nuda was characterized by a short period of alcohol production. Tartaric acid and malic acid, which are the main organic acids in grape juice, had decreased; this was a factor of pH alkalinization. The lack of increase in lactic acid indicated that L. nuda is a basidiomycete that does not undergo malolactic fermentation. The ADHs in L. nuda used both NADH and NADPH as coenzymes. The three ADHs obtained had different molecular weights and, thus, differed in suitable pH, coenzyme and substrate. The ～70 kDa ADH had the highest specific activity for EtOH production. When the use of NADH as a coenzyme, the ～ 100 kDa ADH involved in EtOH production increased the specific activity for butanol production above that for alcohol production.

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We produced amazake (a fermented, sweet, non-alcoholic Japanese beverage) using mushrooms instead of Aspergillus oryzae. Fourteen strains were screened from 55 strains of edible mushroom by amylase activity at 50℃. Thermal stability of amylase was investigated for these strains. Amylase of Grifola frondosa SKB003 and Fuscoporia obliqua NBRC 8681 showed high thermal stability. The optimal medium composition for amylase production in G. frondosa SKB003 and F. obliqua NBRC 8681 was investigated. G. frondosa SKB003 showed extremely high amylase activity, 526 mU/g (50℃) and 565 mU/g (60℃) on brown rice medium. We selected G. frondosa SKB003, and produced amazake with this strain. The total sugar content and reducing sugar content of amazake produced by G. frondosa SKB003 (349.1 g/L and 232.9 g/L) were higher than those for commercial amazake (252.3 g/L and 161.6 g/L). The taste and aroma of amazake produced by G. frondosa SKB003 were good, and a significant difference was not observed for commercial amazake on sensory evaluation.

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Since ancient times in Japan, it has been said that mushrooms grow abundantly after lightning strikes. To verify this mysterious causal relationship, previous studies have reported that artificial lightning exposure can stimulate fruiting body formation, suggesting that fruiting bodies are affected by factors other than electrical stimulation. In this study, it was hypothesized that the stimulation by air-borne sound during lightning strikes is a factor. As a result of cultivation by applying different sound pressures, it was found that the application of 110 dB had the best effect of promoting the onset of fruit body formation. In order to identify the frequency band of the air-borne sound associated with lightning strikes that is effective for promoting fruit body development, we conducted cultivation experiments by extracting and applying different frequency bands and confirmed that fruit body yield peaked by applying sound at frequencies of between 1.5 kHz and 2.5 kHz. These results confirm that the sound of lightning strikes promotes the growth of shiitake mushrooms, and that vibration at specific frequencies of thunder is also one of the factors that promotes fruiting body formation.

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Regarding the culture conditions for the mycelia of Chlorophyllum molybdites (Iwade strain 51), it was clarified that the optimal culture temperature for the mycelia is 25˚C, and the culture medium with rice bran added to bark compost ［bark compost: rice bran = 10 : 1 (w/w), moisture content 65% (wet basis)］ and the culture medium with corn steep liquor added to bark compost ［bark compost: corn steep liquor = 10 : 1 (w/w), moisture content 65% (wet basis)］ produce the fastest mycelial spreading. Regarding the cultivation conditions, it was confirmed that fruiting bodies were generated on the mushroom bed of bark compost with rice bran added ［bark compost: rice bran = 10 : 1 (w/w), moisture content 60 - 65% (wet basis)］, covered with black soil whose pH was adjusted to approximately 7.0 using oyster shell lime, by scratching the mycelia and sprinkling water.

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