Nobuo Toyama

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M14-2 is a cellulase hyperproducer derived from Trichderma reesei QM 6a, but with a growth rate lower than that of the original strain. When M14-2 was autopolyploidized followed by haploidization and selection, the strain with both a higher cellulase productivity per mycelia and a higher growth rate could be obtained as M14-2B. This strain seemed to be(More)
The saccharification of agricultural woody wastes was studied using a commercial enzyme preparation, Cellulase onozuka, derived from Trichoderma viride or the solid culture extracts of the fungus. With the intention of producing sugar at low cost, a simple procedure of enzymatic saccharification of rice straw, bagasse, and sawdust was studied. Delignifying(More)
The mycelial mat of Trichoderma reesei strain QM 6a was treated with 0.1% (w/v) colchicine solution for 14 days and designated M14. The cellulase productivity of strain M14 was not much higher than that of the original strain. When conidia of M14 were treated with ethylmethane sulphonate (EMS) solution, the cellulase hyperproducers, M14-1 and M14-2, were(More)
When the swollen conidia of Trichoderma reesei QM 6a are treated with 0.1% (w/v) colchicine solution, huge autopolyploid nuclei can be formed in those swollen conidia. When a mycelial mat derived from such a conidum is treated with a haploidizing reagent, benomyl, many fan-shaped sectors are produced from the colony, and cellulase hyperproducers are(More)
The multinucleate conidia were produced from the green mature conidia of Trichoderma reesei Rut C-30 strain by colchicine treatment. The strain with higher Filter paper degrading ability was selected among those conidia using a double layer selection medium. The selected strain, JS-2 was able to collapse the filter paper within 15 min but the original(More)
A mycelial mat of Lentinus edodes was treated with 0.01% (w/v) colchicine solution for 240 h at 26 degrees C and autopolyploidization occurred. The mycelia were treated subsequently with the haploidizing reagent, benomyl, and fanshaped sectors were produced from colonies. Among such sectors, cellulase hyperproducers could be selected. The cellulase(More)
Conidia ofTrichoderma reesei QM 9414 were treated with colchicine in order to obtain polyploids (diploids; tetraploids). Cellulase production by diploids (mononucleate conidia) was almost twice as great as that of the original strain, but that of tetraploids (binucleate conidia) was not increased. When these latter conidia were re-treated with 2.0% (w/v)(More)
The cost of cellulase is still a problem for bioethanol production. As the cellulase of Trichoderma reesei is applicable for producing ethanol from cellulosic materials, the cellulase productivity of this fungus should be increased. Therefore, we attempted to develop a system to isolate the strain with higher degrading ability of a filter paper and superior(More)
We have attempted to develop an active selection system for strains that have a higher potential for Avicel degradation using haploidized conidia from colchicine-treated Trichoderma reesei Rut C-30 as a model strain. Avicel, absorbent cotton, and wood powder were used as substrates for selection. It appeared that the strains that degrade Avicel actively(More)