Figure 3.

The effect of phosphate salts (a,b), sulfate salts (c,d), cultivation temperature (e), pH of culture medium (f), and cultivation time (g) on the prodigiosin production by S. marcescens TKU011. Medium with the combination of α-chitin and casein with the ratio of 5/3 (w/w). The culture medium containing 1.5% C/N source, 0.1% FeSO₄(NH₄)₂SO₄ (a,b), 0.05% K₂HPO₄ (c,d). The fermentation was performed at 30 °C in 1 d, and then at 25 °C in the next 2 d, shaking speed of 150 rpm, and a ratio volume of medium: flask of 1:2.5 (v/v). Means of prodigiosin yield (mg/100mL) values with the same letter in each figure are not significantly different based on Duncan’s multiple range test (alpha = 0.01).