Table 3.

Effect of nitrogen sources on xylanase production by A. niger

Nitrogen sources	Conc. (%)	Xylanase activity (IU/gds)
Ammonium sulphate	0.5	333 ± 7.3
	1.0	392 ± 4.7
	1.5	368 ± 8.3
	2.0	357 ± 5.6
Urea	0.5	186 ± 7.7
	1.0	236 ± 7.5
	1.5	457 ± 8.5
	2.0	312 ± 6.5
Peptone	0.5	383 ± 7.09
	1.0	458 ± 13.4
	1.5	464 ± 7.3
	2.0	421 ± 3.7
Yeast extract	0.5	240 ± 8.08
	1.0	445 ± 5.5
	1.5	457 ± 8.5
	2.0	312 ± 6.5
Control	-	182 ± 6.1

“All the experiments were carried out in triplicate and results were presented as mean ± standard deviation.”