Diseases such as thrombosis and cancer are difficult to cure; it is thought that it is desirable to prevent their onset by developing healthy everyday eating habits from the viewpoint of medical and dietary sources and preventive medicine. From ancient times to the present, alcoholic beverages such as sake, beer and wine have been made by yeast fermentation. However, we identified the presence of alcohol dehydrogenase and lactate dehydrogenase in mushrooms, and also confirmed the existence of amylase, protease and milk clotting enzyme. I conducted research aimed at the development of functional foods that show fibrinolytic activity and antithrombin activity in many mushrooms and show effects on thrombosis such as myocardial infarction and cerebral thrombosis. Alcoholic fermentation was carried out using mushrooms having alcohol dehydrogenase instead of yeast, and production of functional wine, beer and sake was attempted. Furthermore, fermentation was carried out using mushrooms containing lactate dehydrogenase, crude enzyme, amylase, and protease. We then prepared cheese, miso, fermented soybeans, fermented plums, fermented soybean milk, and fermented meat having new functionality. As a result, fibrinolytic activity, antithrombin activity and antioxidant activity were found in these fermented foods.

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Using eight species of fungi collected in Japan, we determined the intensity of light emitted by cultured mycelia based on multiple isolates from a single fungal species after two different culture periods and at two different temperatures. The highest luminescent intensity was produced by isolates of Favolaschia peziziformis followed by Dictyopanus gloeocystidiatus, Armillaria mellea, Omphalotus japonicus, Pleurotus nitidus, Mycena chlorophos, Mycena manipularis, and Armillaria tabescens. There were significant differences within the three species that had more than five isolates, D. gloeocystidiatus, O. japonicus, and P. nitidus. All P. nitidus isolates showed greater intensitiy after incubation for 7 d than for 14 d. In contrast, incubation for 14 d yielded greater intensity in M. chlorophos, M. manipularis, and O. japonicus. For one isolate of D. gloeocystidiatus, one isolate of M. manipularis, and four isolates of O. japonicus, the luminescence were significantly more intense at 25℃ than at 15℃. Only one isolate each of D. gloeocystidiatus, M. chlorophos, and P. nitidus had lower intensity at 25℃ than 15℃. Eight isolates from four species showed the highest intensity at 520 nm. The intensity produced by one isolate of A. mellea gradually decreased during measurement for 16 h.

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Rhizopogon roseolus is an ectomycorrhizal mushroom with a worldwide distribution. A recent study reported that a salt-tolerant strain could be produced by cross-breeding this mushroom. However, no studies on the selection of salt-tolerant strains by mutagenesis have been performed. Here, to induce mutations, we treated basidiospores of R. roseolus with ethyl methanesulfonate (EMS), a widely used chemical mutagen, and evaluated the salt tolerance of the recovered mutants. Out of 88 monosporous strains recovered from EMS-treated basidiospores, we selected 5 halophilic strains that showed vigorous mycelial growth on medium containing 300 mM NaCl. Three hybrid strains produced by crossing among halophilic monosporous strains also showed vigorous growth on medium containing 300 mM NaCl. To investigate stability of halophilic characteristics, subculturing was carried out for 6 months. After subculturing, halophilicity was recognized in 2 of the 3 hybrid strains. The 2 halophilic hybrid strains were considered suitable for environments containing NaCl.

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Starch isolated from Japanese red pine (Pinus densiflora) roots was used as a carbon source for cultivation of matsutake mushroom (Tricholoma matsutake) mycelia. Starch-decomposing enzymes were extracted from solid media supplemented with pine starch, in which T. matsutake was grown for 6 months, and the activities of α-glucosidase, glucoamylase and α-amylase were measured. The activities of these three enzymes in extracts from agar medium were lower than in extracts from medium with gellan gum substituted for agar, with no glucoamylase activity in extracts from agar medium. The amylopectin content in extracts from both solid media was low, suggesting decomposition of the amylopectin in the pine starch.

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