The effects of physical-chemical parameters of cultivation (temperature, pH, intensity of medium aeration and degree of shear under agitation) and concentration of reducing sugars (RS) on the growth of the wood-rotting basidiomycete Coriolus hirsutus were studied in a medium with pentose wood hydrolyzate. The values of these parameters, which were optimal for mushroom biomass formation, were found. Optimum concentration of hydrolyzate RS for mushroom growth was shown to be 20-25 g/l. The culture under study was able to grow (increasing pH) at high acidity of the medium, although the optimum level of pH was 5.6-5.8. Maximum specific growth rate of mushroom was recorded at high temperatures of 30-36degreesC. Due to these particular features, the basidium fungus Coriolus hirsutus can be suitable object for biotechnology. During shake-flask fermentation with the aeration level of 0.9-1.2 g O-2/h(-1) and corresponding to aeration the intensity of shearing forces, the mushroom grew in the form of small loose and fluffy pellets, which had more points of growth on a surface. This probably resulted in an increase of biomass concentration under these conditions and the very high efficiency of substrate utilization (eta(x/s) = 0.68). (C) 2004 Elsevier Ltd. All rights reserved.