High Improvement in Lactic Acid Productivity by New Alkaliphilic Bacterium Using Repeated Batch Fermentation Integrated with Increased Substrate Concentration

Table 4

Lactic acid production in repeated batch fermentation by Enterococcus hirae BoM1-2 using initial 60 g L⁻¹ of glucose for the first 10 runs and 100 g L⁻¹ glucose for run 11th.

Batch Number	Initial glucose (g L^−1)		LA conc. (g L^−1)	Fermentation time (h)	(g g^−1)	(g L^−1 h^−1)	Max (g L^−1 h^−1)
1	60	3.80±0.024	59.2±0.4	30	0.99	1.97	3.5
2	60	4.70±0.560	59.0±0.3	24	0.98	2.46	3.8
3	60	6.70±0.063	59.1±0.2	22	0.99	2.69	3.9
4	60	8.40±0.038	57.8±0.2	21	0.98	2.75	3.9
5	60	10.6±0.093	58.8±0.3	20	0.98	2.94	4
6	60	12.3±0.570	58.1±0.9	18	0.97	3.23	4.2
7	60	12.5±0.102	58.8±0.5	16	0.98	3.68	4.5
8	60	12.9±0.097	58.1±0.6	14	0.98	4.15	5.4
9	60	13.3±0.109	58.1±0.4	13	0.97	4.47	5.1
10	60	13.7±0.048	58.3±0.7	13	0.97	4.48	5
11	100	15.0±0.102	97.2±0.9	33	0.97	2.95	3.9

OD, maximum optical density. Maximum lactic acid concentration after 30 h. Lactic acid yield. Lactic acid productivity at the end of fermentation time. Maximum lactic acid productivity at indicated time.