The colonization, primordial formation and fructification of Lyophyllum decastes on cattle livestock composts fermented for one year (C-I) and five-weeks (C-II) were assayed. First, each compost was separately mixed with corn cobs (1:1), and supplemented with various agricultural byproducts. The colonization, primordial development and fructification of Lyophyllum decastes were accelerated by C-I, and barley bran was the most beneficial supplement, just as in ergosterol assimilation and polysaccharide production. The biological efficiencies (BE) recorded for C-I and C-II were 64.8-24.2% and 27.1-12.4%, respectively. The highest BE was produced by C-I when barley bran was used as a supplement, followed by a mixture of wheat, rice, and barley (WRB) brans; corn husk; and cotton waste. In contrast, C-II exhibited slower spawn running, produced a low yield, and had a lengthy fructification period, entailing loss of time, results similar to those of the cotton waste supplement to C-I. The highest polysaccharide content of 70mg/g of dry mushrooms was achieved when barley bran was used as a supplement to the compost.

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This study focuses on the ability of white rot fungi to biodegrade various pesticides through enzymatic activity, in comparison to the manganese peroxidase (MnP) and lignin peroxidase (LiP) activities of edible cultivated mushrooms. In the in vivo pesticide degradation tests using various white rot and brown rot mushroom fungi, the white rot fungi, such as Trametes versicolor, Lentinus tigrinus and Pycnoporus coccineus, were able to decompose the model pesticide, 2,4-D, within less than 2 weeks of incubation with the pesticide. Among the test organisms, T. versicolor showed the highest efficiency of biodegradation for all of the test herbicides, germicides and insecticides, and Pleurotus ostreatus, an edible cultivated mushroom fungus, showed considerable capabilities in the degradation of pesticides. We also demonstrated that the MnP found in the cell free extracts from T. versicolor and P. ostreatus, could decompose the most test pesticides (all but Siduron and o-Phenyl phenol). On the other hand, the LiP found in T. versicolor showed activity against both the pesticides degradable by MnP and o-Phenyl phenol, but not against Siduron. However, P. ostreatus did not show any LiP activity. We also discussed the application of the waste P. ostreatus substrate to the bioremediation of pesticides in agriculture sites.

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We analyzed the vitamin D and ergosterol contents of Grifola gargal, which is the Chilean edible mushroom with a characteristic almond flavor. The cultivated G. gargal mushroom contained remarkably high amounts of vitamin D compared to other cultivated mushrooms, such as maitake (Grifola frondosa) and shiitake (Lentinula edodes). The amount of vitamin D in G. gargal significantly increased with exposure to light from fluorescent lamps during the fruiting body formation period. In addition, the vitamin D content of G. gargal increased up to twenty fold (about 5.3 mg/100g dry wt.) after UV-light irradiation with a 245nm wavelength for 2 hours. Therefore, G. gargal might be not only a new type of edible mushroom with an almond flavor, but also a healthy source of vitamin D for the prevention of rickets in children and osteoporosis in adults.

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Metabolic activation of promutagens in the Ames test was performed using a crude enzyme solution (S9) extracted from a rat liver. We hope to be able to substitute enzymes produced by microorganisms for enzymes extracted from animals. We tried metabolically activating promutagens using an extracellular and mtracellular enzyme solution prepared from white-rot fungi. The mtracellular enzyme solution from Corlolus versicolor reacted strongly to 2-Ammoanthracene (2AA) and 3-amino-1-methyl-5H-pyndo[4,3-a]-indole (Trp-P-2) in comparison to enzyme solutions from Phanerochaete chrysosporium and extracellular enzymes from C. versicolor. We examined the various kinds of promutagens with the mtracellular enzymes of C. versicolor. Assuming the number of revertants to be 1.0 when mtracellular enzymes are not added, it was found that the number of revertants increased 2.8 times in Aflatoxin B_1 (AFB_1), 3.1 times in 2-Aminofluorene (2AF), 3.6 times in 4-Nitroquinoline (4NQO), 3.7 times in Benzo[a]pyrene (BaP), 4.0 times in 2AA and 4.7 times in Trp-P-2. These results indicate that the crude enzymes of the white-rot fungi perform the metabolic activation of promutagens.

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We designed and constructed a prototype of a large culture bottle for pine seed-lings with the shiro-like structure of the matsutake mushroom. As the root systems of these seedlings, grown under several soil conditions, could be manipulated with-out destroying the soil structures, the seedlings grown in this culture bottle would be suitable for use in acclimation studies concerning mushroom cultivation.

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