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

Table 3

Effect of different initial pH values of fermentation medium on the production of α-amylase by P. stutzeri AS22.

Initial pH value	Final pH value	Biomass (OD600)	α-Amylase activity (U/mL)
6.0	4.73	3.9	0
7.0	7.2	4.9	3.8
8.0	8.0	5.6	5.9
9.0	8.55	5.5	5.85
10.0	8.9	5.5	5.8
11.0	9.22	5.6	5.6
12.0	9.32	5.4	5.4

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, K₂HPO₄ 1.4, KH₂PO₄ 0.7, MgSO₄ 0.1, and NaCl 0.5 and were adjusted to different initial pH values.