Degradation of styrene monomer and polystyrene by a white-rot fungus Phanerochaete chrysosporium was examined. As degradation products of styrene monomer, 4-hydorxy benzoic acid and mandelic acid were detected, which were not determined in styrene-metabolizing bacteria. However, degradation of polystyrene was not determined with any chemical changes. Reactivity of styrene monomer and polystyrene was simulated with a semi-empirical molecular orbital calculation program MOPAC. One pathway of styrene degradation is estimated as the initial hydroxylation at 4-position of styrene and the following oxidation to form 4-hydroxy benzoic acid. Another is predicted as the oxidation of the vinyl group to form mandelic acid. As a result of the HOMO calculation of styrene oligomers, the energy level was slightly lower than that of styrene monomer at 4-position of aromatic ring. Therefore, the low biodegradability of polystyrene is estimated to be due to its high hydrophobicity.

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Using raw or defatted rice bran as a supplement, 5mg to 20mg per kilogram thiamine was added to the sawdust-based substrates. We examined the mycelial growth, yield and contents of major chemical components and thiamine of the fruit bodies of Lentinula edodes. The addition of thiamine did not influence the mycelial growth, yield or major chemical components of the fruit bodies. However, the fruit bodies developed on the substrate using raw rice bran added with lOmg/kg thiamine contained three times more thiamine than those on the substrates without thiamine, and those on the substrate using defatted rice bran two times. The thiamine contents of the fruit bodies developed on the substrates using raw rice bran declined according to the fruit body flushes during harvest, but those on the substrates using defatted rice bran increased. This meant that the thiamine contents of fruit bodies differed during harvest according to the supplement used for the substrates.

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Three dry cattle manures and one cattle manure compost collected from beef cattle fattening farms were tested the possibility of use as medium to cultivate Agaricus bisporus and its capability of rot. In experiment 1, 3% of the grain spawn of A bisporus to medium mass was inoculated. The first fruit-bodies were harvested at 41 days after inoculation, and the weights of fruit-bodies were measured until 86 days after inoculation. The fruit-bodies were harvested in all tested cattle manures. The higher yield of fruit-body was obtained with the dry cattle manure lower content of sawdust and shorter time of aerobic fermentation (P<0.05). The pH values of all manures declined with the cultivation of A. bisporus. The contents of nitrogen, phosphorus and ash were increased. Meanwhile the content of carbon and the ratio of carbon and nitrogen were decreased. In experiment 2, the dry cattle manure obtained the highest yield of fruit-body in experiment 1 was used as medium, and 1% of the grain spawn of A. bisporus to medium mass was inoculated. The dry matter degradation of manure was 20.0% at 81 days after inoculation. The contents of plant cell wall, cellulose, hemicellulose and lignin in manure were decreased by the cultivation.

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