This study was designed to examine the effects of several individual mushroom species and a mixture of species, on systolic blood pressure and hypertension. Our experiments focused on three groups of mushroom samples: 1) Lentinula edodes; 2) Lyophyllum decastes; 3) Grifola frondosa, Ganoderma lucidum and Lentinula edodes (weight ratio 2:2:1). The doses were scaled down to the weight of rats based on human weight (5, 10, 15g/60kg/600ml/day), and given daily to 13-week-old, spontaneously hypertensive rats for 27 weeks. The results indicated that the first two individual mushroom species decreased systolic blood pressure in a dose-dependent manner. In comparison with the untreated control SHR group, systolic blood pressure was significantly reduced in rats that received Lentinula edodes at the high dose, and in those that received Lyophyllum decastes at either the high or medium dosages. It was thought that the mechanism of antihypertension was different in Lentinula edodes and Lyophyllum decastes. Rats that received the mixture of the three mushroom species showed no significant reduction in systolic blood pressure. The first two individual mushroom species, which proved to be effective in decreasing hypertension, indicated improved lipid metabolism and kidney function, thus suggesting the relevance of endogenous vasopressor materials.

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The acetone extract from the fruit body of Sarcodon aspratus (Berk.) S. Ito showed moderate angiotensin I converting enzyme (ACE) inhibitory activity, dMannitol was isolated from S. aspratus by sequential extraction with w-hexane and acetone followed by purification with activated char powder. Yield of the compound was 0.3% based on dry material. D-Arabitol was also found in the acetone extract. These compounds showed moderate ACE inhibitory activities, and the concentrations required to inhibit 50% of the ACE activity (IC_<50>) were 33.4 and 34.5mg/ml, respectively. The inhibition patterns on ACE of these two polyhydric alcohols and D-sorbitol (IC_<50> value: 31.9mg/ml) were investigated using LineweaverBurk plots. As a result, they acted as competitive inhibitors for ACE, suggesting that they are antagonists against the substrate binding to the active site of ACE. These results also indicated that polyhydric alcohols that consisted of a straight chain with more than five carbon atoms were more potent inhibitors.

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We examined the fruit body yields of Lentinula edodes in three flushes on the sawdust substrates with six kinds of additives, raw rice bran, fat-free rice bran, wheat bran, raw rice bran and wheat bran, fat-free rice bran and wheat bran, and a commercial supplement. Then, the evaluations of the fruit bodies for the seven items, appearance, color and smell before consumption, smell, taste, texture after consumption, and total evaluation, in the three flushes were examined using the token method of sensory analysis. Times of flush which gave more yield than the others differed according to the kind of additives. The results from the sensory analysis showed the evaluations of fruit body taste differed according to the kind of additives and times of flush which gave more yield than the others. By the total yield in the three flushes and the total evaluation of sensory analysis in each flush, the substrate with fat-free rice bran and wheat bran showed high score by evaluation.

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In this research, we studied the cultivation properties and fruiting body formation of Strobilurus ohshimae in order to cultivate it commercially. Optimal temperature of mycelial growth was 25℃, and mycelia also grew quickly at a low temperature compared to other edible mushrooms. We tried to form the fruiting body of S. ohshimae. However, the fruiting body was not formed with the method generally used for the cultivation of edible mushrooms. Then we observed the fruiting body formation of S. ohshimae in the natural environment. Usually the fruiting bodies were formed on buried sugi twigs. We collected the twigs on which the fruiting bodies of S. ohshimae formed, and we removed the fruiting bodies from them. Then the twigs were cased with forest-soil and incubated at 15℃. Consequently, fruiting bodies were formed on the twigs. We also cased a sugi-wood-meal medium with forest-soil after spawn running, and fruiting bodies were formed on 4 out of 12 of the cultures. Furthermore, we tried to improve the rate of fruiting body formation, and the fruiting body was formed on 12 out of 12 of the cultures by casing with vermiculite.

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