Out of 165 strains of basidiomycetous yeasts tested, which represented
50 species of 20 genera, 80% were capable of utilizing xylan as a sol
e carbon source. These strains belonged to species of the genera Apiot
richum, Atractogloea, Cryptococcus, Endophyllum, Filobasidium, Gymnosp
orangium, Holtermania. Microstroma, Tremella, and Trichosporon. The ab
ility to produce extracellular xylanases is especially widespread amon
g the Cryptococcus species. Among the four C. podzolicus strains studi
ed in detail, the maximum level of xylanase activity was revealed for
strain VKM X-2.