Table 2. Effect of aeration on growth and EPS production by H. xianhensis SUR308.

Culture volume: flask volume ratio (CVF)	Growth		Production of EPS, g/L
	OD at 540 nm	DCW, g/L
1.0:10	3.82 ± 0.11	1.52 ± 0.02	2.48 ± 0.03
1.5:10	4.28 ± 0.02	1.36 ± 0.03	2.85 ± 0.04
2.0:10	4.10 ± 0.08	1.44 ± 0.07	2.66 ± 0.04
2.5:10	4.12 ± 0.04	1.52 ± 0.03	2.62 ± 0.02
3.0:10	3.04 ± 0.08	1.81 ± 0.01	1.89 ± 0.02
3.5:10	3.02 ± 0.06	1.89 ± 0.02	1.76 ± 0.02
4.0:10	2.96 ± 0.06	1.76 ± 0.03	1.67 ± 0.02
5.0:10	2.88 ± 0.04	1.69 ± 0.02	1.56 ± 0.02

Fermentations were carried out in MY medium [(g/L): NaCl, 50; MgCl₂·6H₂O, 9; MgSO₄·7H₂O_, 13; CaCl₂·2H₂O, 0.2; KCl, 1.3; NaHCO₃, 0.05; NaBr, 0.15; FeCl₃·6H₂O, 0.005; glucose, 10; yeast extract, 3; malt extract, 3; protease peptone, 5; pH 7.2] inoculated with 2% (v/v) inoculum and incubated at different aeration rates (culture volume:flak volume 1:10–5:10) under continuous shaking (120 rpm) at 32 °C. All values were taken in triplicates and the average ± SE was recorded after 11 days of incubation. One way ANOVA has been carried out for each row with the P value of 0.05. Bonferroni's post-test shows the production of EPS and DCW were significantly different (P < 0.05) against growth (OD at 540 nm) while EPS production against DCW was not significant (P > 0.05).