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木质纤维素在预处理的过程中会产生呋喃类、酚类和弱酸类物质,抑制菌株的生长和发酵。研究了典型抑制剂糠醛、苯酚和乙酸对可利用纤维二糖的工程酿酒酵母菌株生长和发酵的影响,考查了分别以纤维二糖和葡萄糖作为单一碳源时菌株对抑制剂的耐受能力。结果发现,糠醛对菌株的纤维二糖和葡萄糖利用能力的抑制作用随糠醛浓度增加而增大。低浓度(≤0.5 g/L)的苯酚对纤维二糖利用有一定的促进作用,高浓度(1.5 g/L)的苯酚会抑制菌株的生长和发酵。乙酸对菌株纤维二糖利用的影响最为显著,可以明显抑制菌株的生长、纤维二糖利用和乙醇生产,而一定浓度(0.5~4.0 g/L)的乙酸会促进葡萄糖的利用。研究中还发现,复合抑制剂对纤维二糖利用菌株的抑制作用强于单一抑制剂。
Lignocellulose in the pretreatment process will produce furans, phenols and weak acids, inhibit the growth of strains and fermentation. The effects of furfural, phenol and acetic acid, a typical inhibitor, on the growth and fermentation of engineering Saccharomyces cerevisiae cells using cellobiose were studied. The tolerance of the strains to inhibitors when the cellobiose and glucose were used as single carbon sources was investigated. As a result, it was found that the inhibitory effect of furfural on the cellobiose and glucose utilization ability of the strain increased as the furfural concentration increased. Phenol with low concentration (≤0.5 g / L) could promote cellobiose utilization. High concentration (1.5 g / L) of phenol inhibited the growth and fermentation of the strain. Acetic acid has the most significant effect on cellobiose utilization, and can significantly inhibit the growth of strain, cellobiose utilization and ethanol production, while acetic acid of certain concentration (0.5-4.0 g / L) can promote the utilization of glucose. In the study, it was also found that the composite inhibitors inhibited cellobiose-utilizing strains more strongly than single inhibitors.