We produced mirin (Japanese fermented alcoholic seasoning) using mushrooms instead of Aspergillus oryzae. Thirteen strains were screened from 91 strains of edible mushrooms as high amylase-producing strains, and alcohol tolerance of amylase produced by these strains was investigated. Amylase of Ganoderma lucidum NBRC31863 showed the highest tolerance in the presence of 20% ethanol (the activity was 89.5% of that in the absence of ethanol). The amylase activity of commercial rice koji (Aspergillus oryzae) under the same conditions was 72.3%. We selected Ganoderma lucidum NBRC31863 and three other mushrooms strains, and produced mirin using these strains. Mirin produced by Mucidula mucida var. asiatica SKB021, and G. lucidum NBRC31863, showed high total sugar content in the mushroom mirin produced (180 g/L, and 177 g/L, respectively), although it was lower than that of commercial mirin (425.6 g/L). The organic acid content and amino acid content of mushroom mirin were both higher than commercial mirin. Furthermore, mushroom mirin showed high antioxidative activity, and the DPPH radical scavenging activity of mirin produced by M. mucida var. asiatica SKB021 was 33.3 nmol-Trolox/mL, which is one of the advantages of using mushrooms for mirin production. The taste and aroma of mirin produced by G. lucidum NBRC31863 was good, and no significant difference was observed compared to commercial mirin in sensory evaluations.

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The Basidiomycete Rhizopogon roseolus (Corda) Th. Fr. (= Rhizopogon rubescens Tul. & C. Tul.) is an ectomycorrhizal mushroom with salt tolerance. To obtain more salt tolerant strains, we examined intraspecific variation in the salt tolerance of basidiospore isolates, and evaluated the salt tolerance of crossed-strains generated by crossing basidiospore isolates. Inocula were grown on nutrient-poor Modified Melin-Norkans agar medium containing different concentrations of NaCl, and radial mycelial growth was measured after 16 days of incubation. Intraspecific variation in salt tolerance was observed among both basidiospore isolates and crossed-strains. When crossed with salt tolerant basidiospore isolates, some of the strains showed higher salt tolerance than their parental wild strains, showing the promise of producing salt tolerant strains by cross-breeding.

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Generally speaking, the physical properties and taste of yogurt are changed by cryopreservation. However, the physical properties and taste were unchanged and the survival ratio of lactic acid bacteria was improved by the addition of "kinoko koji" to yogurt.

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The enormous number of spores produced by fruiting bodies of edible mushrooms including Pleurotus cornucopiae var. citrinopileatus can lead to allergic reactions in workers involved in its cultivation. A cultivar harboring a sporulation-deficient (sporeless) mutation would be very useful for preventing these problems. In this study, using a sporeless trait from P. cornucopiae var. citrinopileatus, we report the development of a sequence-tagged site (STS) marker from a bulked segregant analysis-based amplified fragment length polymorphism (BSA-AFLP) marker, linked to the sporeless locus, for establishment of marker-assisted selection in breeding for the sporeless trait. Its practicality was validated by a test against 11 wild-type (sporulation-type) isolates of different geographical origins.

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