The purpose of this study was to clarify consumer expectations for mushroom functionalities. Analysis was performed using the results of an Internet questionnaire survey on consumers. In addition, covariance structure analysis was applied to estimate the structure of consumer expectations for mushroom functionalities. Some respondents expressed their expectations for mushroom functionalities. The degree of expectations differed by sex and age. Health maintenance and disease prevention were the major expectations for mushroom functionalities. Based on covariance structure analysis, the higher the preference for mushrooms and preference for functional agricultural products and foods, the higher the expectations for mushroom functionalities.

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To obtain preliminary data for establishing a sake brewing method with high umami components, rice proteins were degraded by edible mushroom proteases to produce amino acids, and the amino acid profiles were examined. Amtlase addition was necessary for liquefaction of the moromi (fermentation mush) treated with the crushed mushrooms. After treatment for 48 hours at 30℃, characteristic amino acid profiles were determined for the moromi treated with mushroom enzymes. Taste-related amino acids, such as glutamic acid, accumulated in the moromi with shiitake mushroom as the enzyme source.

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The sawdust of willows, Salix udensis and Salix pet-susu, which are known as fast growing trees and have gained attention as woody biomass resources, was investigated for its applicability as a substrate for the sawdust-based cultivation of Pleurotus eryngii. For bag cultivation, the yield on the willow substrate was 1.55 times greater than that using the birch (Betula platyphylla) substrate. For bottle cultivation, the yield on the willow substrate was 1.14 times greater than that on the corncob substrate, even though the weight of the willow substrate per bottle was less than that of the corncob substrate. Chemical components exhibited significant differences among individual sawdust and corncob samples. The characteristics of the two willow species showed an intermediate position. In the sensory evaluation of the taste and texture of fruiting bodies, those cultivated on the willow substrate were evaluated as the highest. These results suggest that S. udensis and S. pet-susu will be useful as resources for the sawdust-based cultivation of P. eryngii.

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A newly isolated glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter from Pleurotus salmoneostramineus was used for the expression of a hygromycin B resistance gene in a transformation study of the monokaryons, which are monosporous isolates from P. salmoneostramineus NBRC31859. The promoter site was set at 1,100 bp upstream of this gene, the hygromycin B resistance gene was introduced, and colonies resistant to 50 mg/mL hygromycin B were detected. Southern blotting analysis of transformants indicated that the integration of the gene occurred by non-homologous end-joining. These methods could be useful for functional gene analyses to study monokaryotic fruit body formation in P. salmoneostramineus.

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Shiitake mushrooms (Lentinula edodes) are dried for long-term storage. Most of the dried shiitake produced in Japan are cultivated on logs. The conventional shiitake-drying method has been developed for many years to improve the appearance, which is the main value standard of dried shiitake. Recently, a new drying method has been developed to expand consumption of dried shiitake. This new drying method places an emphasis on the taste of soup stock instead of the appearance, which was the focus of the conventional drying method. Shiitake mushrooms were dried by the conventional and new methods, and the contents of free sugar, free amino acids, 5'-GMP, ergothioneine, and eritadenine were compared between the shiitake dried by the different methods. The contents of some ingredients in the log-cultivated dried shiitake varied among individual mushrooms depending on the growth environment and the state of the mushrooms harvested. Therefore, the differences in the ingredient contents due to the drying method were not always common to all test lots. However, shiitake dried by the new method tended to have slightly higher contents of trehalose, glucose, 5'-GMP, and sour or umami amino acids, and slightly lower contents of bitter amino acids than shiitake dried by the conventional method.

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Ezoharitake (Climacodon septentrionalis) is an edible mushroom in the Phanerochaetaceae family. Biological activities and novel compounds in mycelial and fruiting body extracts have been reported and they could be useful bioresources. However, the effective cultivation methods of this mushroom have not been sufficiently studied. In this study, when mycelial running was completed, the culture medium was subjected to flushing treatments that included scratching, thumping, casing, and bag-cutting. A low yield of fruiting bodies was obtained in the medium treated with scratching and thumping. No fruiting body formation was observed in the medium treated with casing. A high yield of normal fruiting bodies was observed in the medium treated with bag-cutting. Short-term fruiting after bag cutting was observed in the medium cultured for 50 to 60 days at 25°C. Fruiting body formation was observed at 17°C and 19°C, but not at 15°C. The yield of fruiting bodies at 19°C was higher than that at 17°C. These results suggest that sustainable fruiting body formation can be achieved in medium cultured for 50 to 60 days, with bag-cutting treatment, and incubation at 19°C.

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Sawdust-based cultivation of Ganoderma lucidum and G. sinense on growth medium containing bamboo chips was evaluated. The results showed that in both G. lucidum and G. sinense, the time required for mycelial colonization of growth medium could be shortened by substituting medium with 10%, 20%, 30%, 40% and 50% bamboo chips without any adverse effect on fruit-body yield. Substitution of the growth medium with 100% bamboo chip medium did not shorten the time required for mycelial colonization of the medium in both G. lucidum and G. sinense, and decreased fruit-body yield. The results suggested that substituting growth medium with 10 - 50% bamboo chips is beneficial for decreasing the culture period without affecting fruit-body yield.

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