High-level production of poly-γ-glutamic acid from untreated molasses by Bacillus siamensis IR10

Table 2 Effect of carbon sources on γ-PGA production by B. siamensis SB1001 and mutant strain IR10

Carbon source	12 h				24 h				Biomass (P value)
	Biomass (g/L)		γ-PGA (g/L)		Biomass (g/L)		γ-PGA (g/L)		Biomass (P value)
	SB1001	IR10	SB1001	IR10	SB1001	IR10	SB1001	IR10	SB1001	IR10
Glucose	2.31 ± 0.08	3.96 ± 0.12	1.37 ± 0.05	5.60 ± 0.23	4.49 ± 0.18	4.82 ± 0.21	2.77 ± 0.11	7.74 ± 0.35	1.76 × 10⁻⁶	2.44 × 10⁻⁶
Fructose	2.69 ± 0.07	4.25 ± 0.13	0.34 ± 0.01	4.99 ± 0.18	4.56 ± 0.17	4.86 ± 0.21	0.36 ± 0.02	7.21 ± 0.26	1.32 × 10⁻⁶	2.36 × 10⁻⁶
Sucrose	2.52 ± 0.08	4.71 ± 0.13	5.24 ± 0.23	5.70 ± 0.21	4.07 ± 0.14	6.22 ± 0.28	7.06 ± 0.26	7.14 ± 0.25	9.59 × 10⁻⁷	2.77 × 10⁻⁶
Glycerol	1.52 ± 0.05	2.99 ± 0.09	1.95 ± 0.06	3.23 ± 0.12	3.33 ± 0.14	6.67 ± 0.26	3.82 ± 0.15	6.81 ± 0.22	2.15 × 10⁻⁶	1.56 × 10⁻⁶
Maltose	2.58 ± 0.08	4.08 ± 0.11	0.33 ± 0.01	3.32 ± 0.11	4.36 ± 0.16	5.97 ± 0.23	0.55 ± 0.03	6.98 ± 0.22	1.24 × 10⁻⁶	1.49 × 10⁻⁶
Mannose	0.02 ± 0.01	4.18 ± 0.12	0	4.09 ± 0.15	0.02 ± 0.01	4.80 ± 0.21	0	7.11 ± 0.24	1	2.48 × 10⁻⁶
Xylose	1.35 ± 0.05	2.47 ± 0.06	0.31 ± 0.01	1.73 ± 0.05	4.36 ± 0.18	5.88 ± 0.22	0.64 ± 0.02	6.22 ± 0.18	1.98 × 10⁻⁶	1.33 × 10⁻⁶
Lactose	0.42 ± 0.02	4.46 ± 0.14	0	3.79 ± 0.14	1.38 ± 0.03	5.79 ± 0.20	0	7.09 ± 0.25	1.95 × 10⁻⁷	9.65 × 10⁻⁷
Galactose	0.18 ± 0.01	1.27 ± 0.13	0	0	0.51 ± 0.02	3.09 ± 0.15	0	0.72 ± 0.03	2.88 × 10⁻⁶	3.81 × 10⁻⁶

Initial biomass (0 h) 0.02 g/L; Statistical analysis was performed for the biomass at 0 h and 24 h. P-values < 0.05 showed the significant differences

ISSN: 1475-2859