An alkalotolerant Cephalosporium (NCL 87.11.9) strain capable of rapid
growth and xylanase secretion over a wide pH range (pH 4-10) has been
isolated from soil samples. When grown in shake flasks on a wheat bra
n, yeast extract medium for 96 h it produced 15 to 18 IU/ml. The novel
feature of this study is that it is the first report of an extracellu
lar fungal xylanase which is active and stable at high alkaline pH (8-
9.5). The culture filtrate did not show any significant cellulase acti
vity. Gel filtration studies indicated two peaks of xylanase activitie
s corresponding to molecular weights of 70,000 and 30,000 in the propo
rtion of 10:90.