Table 2: Effect of nitrogen sources on protease production by B. circulans MTCC 7942.

Nitrogen supplementation (1%)#Protease activity
(U/mL SD)
Specific activity
(U/mg SD)

Feather meal
Bovine serum albumin
Beef extract
Casein
Casamino acids
Yeast extract
Gelatin
Peptone
Soybean meal

Basal medium containing (g/L): starch, 20; KH2PO4, 1; MgSO4·7H2O, 0.05; CaCl2, 1; Na2CO3, 8 and cultural parameters (pH 10.0) at 37°C and 100 rpm.