Coproduction of menaquinone-7 and nattokinase by Bacillus subtilis using soybean curd residue as a renewable substrate combined with a dissolved oxygen control strategy

Table 2 Experimental conditions for the central composite design and responses showing both the original and scaled factors

Run	Nutritional factors (g/L)			MK-7 production (mg/L)			NK activity (U/mL)
Run	Soybean curd residue (A)	Soya peptone (B)	Lactose (C)	Experimental	Standard error	Predicted	Experimental	Standard error	Predicted
1	130	55	25	35.81	1.16	35.61	1534.13	297.76	1521.28
2	140	45	30	23.954	2.22	24.52	930.32	88.04	956.94
3	130	55	25	35.49	6.73	35.61	1516.47	283.96	1521.28
4	130	55	25	36.61	2.39	35.61	1564.83	185.67	1521.28
5	113.18	55	25	33.306	4.44	33.70	1412.21	333.41	1414.78
6	120	65	30	31.766	3.95	32.49	1315.84	78.59	1363.68
7	130	55	25	36.49	4.35	35.61	1559.74	227.07	1521.28
8	130	71.82	25	29.078	7.20	26.35	1150.34	286.61	1006.75
9	140	65	30	24.01	2.91	25.76	932.44	86.67	1004.62
10	130	55	16.59	32.004	2.74	30.41	1326.18	131.38	1227.97
11	146.82	55	25	28.406	5.83	25.87	1121.47	80.63	1003.12
12	120	45	30	31.528	1.95	30.65	1305.27	340.87	1254.55
13	120	65	20	29.26	0.83	30.21	1158.19	157.25	1213.44
14	140	45	20	25.13	3.51	25.92	980.41	54.33	1014.43
15	120	45	20	28.728	5.71	28.50	1135.23	202.89	1144.91
16	130	55	25	35.67	0.09	35.61	1523.82	211.53	1521.28
17	130	38.18	25	23.282	2.16	23.87	881.23	104.61	909.04
18	130	55	25	33.23	4.66	35.61	1408.82	157.54	1521.28
19	140	65	20	24.626	1.55	27.02	888.91	133.96	1021.50
20	130	55	33.41	31.71	2.53	31.16	1323.54	291.17	1305.97

ISSN: 1869-2044