Physiological mechanism of improved tolerance of Saccharomyces cerevisiae to lignin-derived phenolic acids in lignocellulosic ethanol fermentation by short-term adaptation

Table 1 Effect of phenolic acids on the growth and fermentation performance of S. cerevisiae

Phenolic acids	Concentration (g/L)	μ ^b_max (h⁻¹)	GI^b (%)	Lag phase (h)	Y ^b_x/s (g/g)	Q_glucose (g/L/h)	Q_EtOH (g/L/h)	Y_EtOH (%)
Vanillic acid	0	0.38	0	3	0.24	3.03	1.37	84.34
	0.33	0.35	7.78	3	0.21	3.07	1.25	81.17
	0.75	0.36	6.64	3	0.19	2.68	1.13	80.80
	1.5	0.33	13.99	3	0.16	2.47	0.88	84.65
	2.25	0.18	53.60	9	0.11	1.15	0.51	80.55
	3.0	0.00	99.55	15	0.03	0.78	0.24	61.14
p-hydroxybenzoic acid	0	0.37	0	3	0.25	3.00	1.27	82.79
	2.0	0.36	5.48	3	0.20	3.07	1.23	78.01
	2.5	0.33	12.20	3	0.18	3.00	1.25	80.36
	3.0	0.30	21.63	3	0.17	2.02	0.82	79.29
	4.0	0.20	45.88	9	0.14	1.17	0.50	82.62
	5.0	0	100	15	0.02	0.75	0.19	49.02
Syringic acid	0	0.38	0	3	0.26	2.87	1.26	85.96
	0.25	0.36	6.01	3	0.26	2.80	1.23	86.25
	0.5	0.36	5.05	3	0.23	2.62	1.17	84.62
	1.0	0.34	11.19	3	0.22	2.45	0.82	86.48
	1.5	0.30	20.98	3	0.20	2.40	0.61	83.11
	2.0	0.27	29.03	3	0.18	2.23	0.63	87.77
V–H–S^a	0	0.37	0	3	0.26	2.82	1.27	86.06
	0.5–0.3–0.25	0.33	9.83	3	0.25	2.82	1.09	75.76
	1.0–0.6–0.5	0.23	38.77	3	0.20	1.92	1.05	71.06
	1.5–0.9–0.75	0.16	57.39	9	0.08	0.72	0.22	59.62
	2.0–1.2–1.0	0	100	15	0.03	0.10	0.08	21.36
	2.5–1.5–1.25	0	100	24	0.02	0	0	0

^aV–H–S represented the cocktail of vanillic acid, p-hydroxybenzoic acid and syringic acid
^bμ_max and Y_x/s represented the maximum specific growth rate and biomass yield during initial 15 h, respectively; GI is the growth inhibition rate
^cY_EtOH was the ratio of maximum ethanol concentration to the theoretical ethanol from the total glucose in the medium within 24 h of culture period

ISSN: 2731-3654