Production and Biochemical Characterization of a High Maltotetraose (G4) Producing Amylase from Pseudomonas stutzeri AS22

Table 4

Effect of supplementation of the culture medium with various salts on the production of α-amylase by P. stutzeri AS22.

Chemicals	Concentration (g/L)	Final pH value	Biomass (OD600)	α-Amylase activity (U/mL)
None		7.2	4.77	3.5
Control		7.8	5.45	5.9
NaCl	0.5	7.32	4.9	3.8
K2HPO4	1.4	7.6	2.57	5.19
KH2PO4	0.7	7.7	2.01	5.9
MgSO4	0.1	7.08	5.43	4.13
	0.4	7.0	6.35	4.42
	0.8	7.3	5.73	3.24
CaCl2	0.1	6.9	7.15	6.01
	0.4	6.7	6.3	6.6
	0.8	6.5	6.19	6.5
	1.2	6.3	6.2	4.6
Control + CaCl2 (0.4 g/L)		7.2	6.2	6.8

Cultivation was performed for 24 h at 30°C with shaking at 200 rpm in media that consisted of (g/L) potato starch 10, yeast extract 5, and different salts and were adjusted to pH 8.0. Control: potato starch 10, yeast extract 5, K₂HPO₄ 1.4, KH₂PO₄ 0.7, MgSO₄ 0.1, and NaCl 0.5 g/L.