Xylanase active at high pH from an alkalotolerant Cephalosporium species

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 bran, 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 extracellular fungal xylanase which is active and stable at high alkaline pH (8–9.5). The culture filtrate did not show any significant cellulase activity. Gel filtration studies indicated two peaks of xylanase activities corresponding to molecular weights of 70,000 and 30,000 in the proportion of 10:90.