Bioprocess Engineering Aspects of Biopolymer Production by the Cyanobacterium Spirulina Strain LEB 18

Table 1

Metabolic type, carbon sources, and growth parameters for Spirulina strain LEB 18 cultivated with different carbon sources. The same superscript letter in the same column indicates no significant difference at the 95% confidence level.

Metabolic type and carbon sources	Carbon source   concentration (g L^−1)	Growth parameters
		Maximum cell concentration (, g L^−1)	Maximum specific growth rate (, d^−1)	Maximum cell productivity (, g L^−1 d^−1)	Biopolymers yield (η, grams of biopolymer per gramof LEB 18 biomass)
Glucose (see column 2 for concentration), 16.8 g L^−1 NaHCO3, and 0.25 g L^−1 NaNO3	0.2	0.74 ± 0.12^a	0.06 ± <0.006^abc	0.10 ± 0.01^bc	11.33 ± 1.09^a
	0.4	0.72 ± 0.11^a	0.06 ± <0.006^bcd	0.13 ± 0.02^ab	12.30 ± 0.22^a
	0.6	0.69 ± 0.16^a	0.04 ± <0.006^a	0.17 ± 0.01^a	10.05 ± 1.34^a
Sodium acetate (see column 2 for concentration), 16.8 g L^−1 NaHCO3, and 0.25 g L^−1 NaNO3	0.2	0.65 ± 0.15^a	0.09 ± <0.006^ef	0.05 ± 0.02^de	11.58 ± 0.27^a
	0.4	0.69 ± 0.10^a	0.09 ± <0.006^def	0.08 ± 0.02^cde	11.32 ± 3.17^a
	0.6	0.77 ± 0.17^a	0.08 ± <0.006^cdef	0.09 ± 0.00^bcd	11.93 ± 0.69^a
NaHCO3 (see column 2 for concentration) and 0.25 g L^−1 NaNO3	8.4	0.86 ± 0.01^a	0.07 ± 0.01^cdef	0.05 ± 0.01^cde	44.19 ± 0.15^b
	16.8	0.86 ± 0.17^a	0.06 ± 0.01^bcd	0.06 ± 0.02^cde	40.00 ± 1.88^b
	25.2	0.79 ± 0.01^a	0.09 ± <0.006^def	0.05 ± 0.00^de	37.57 ± 3.16^b
Glucose (see column 2 for concentration) and 0.25 g L^−1 NaNO3	0.2	0.73 ± 0.06^a	0.08 ± <0.006^def	0.08 ± 0.00^cde	11.31 ± 0.20^a
	0.4	0.64 ± 0.07^a	0.05 ± <0.006^ab	0.10 ± 0.01^bcd	10.38 ± 2.88^a
	0.6	0.65 ± 0.01^a	0.07 ± <0.006^cde	0.13 ± 0.02^ab	10.77 ± 0.47^a
Sodium acetate (see column 2 for concentration) and 0.25 g L^−1 NaNO3	0.2	0.65 ± 0.11^a	0.09 ± 0.01^f	0.04 ± <0.006^e	7.64 ± 0.46^a
	0.4	0.63 ± 0.05^a	0.07 ± 0.01^cdef	0.05 ± 0.01^cde	8.18 ± 0.70^a
	0.6	0.68 ± 0.03^a	0.08 ± <0.006^cdef	0.04 ± <0.006^de	7.83 ± 0.01^a
Unmodified Zarrouk media containing 16.8 g L^−1 NaHCO3 and 2.5 g L^−1 NaNO3 (control)	16.8	0.77 ± 0.01^a	0.12 ± <0.006^g	0.04 ± <0.006^de	10.26 ± 0.60^a