Beer production generates brewer's spent grain as a byproduct. This biomass contains lignin, cellulose, and hemicellulose, and can be used for the production of second‐generation (2G) ethanol and xylitol. For this to be economically viable, fermentable fractions must be used, allowing the conversion of cellulose and hemicellulose to ethanol. This study evaluated the fermentation of hemicellulose liquor from brewer's spent grain (HLBS) in aerobic and oxygen‐ limited conditions using Scheffersomyces stipitis and Pachysolen tannophilus. Results were compared with data obtained in a complex medium (YPX) and a minimal medium (MMX). In aerobic conditions, for S. stipitis in the HLBS medium, μ _max = 0.12 h⁻¹, Y _{ethanol/xylose} = 0.14 and selectivity for ethanol over xylitol (S _{ethanol/xylitol}) 3.4 g_ethanol g⁻¹ _xylitol were obtained. Under oxygen‐limited conditions, Y _{ethanol/xylose} = 0.22 and S _{ethanol/xylitol} = 1.17 g_ethanol g⁻¹ _xylitol were obtained. For P. tannophilus, under aerobic conditions, the HLBS medium gave μ _max = 0.08 h⁻¹, and Y _{ethanol/xylose} = 0.005, with selectivity for ethanol over xylitol (S _{ethanol/xylitol}) of 0.12 g_ethanol g⁻¹ _xylitol. In oxygen‐limited conditions, Y _{ethanol/xylose} = 0.09 and S _{ethanol/xylitol} = 0.20 g_ethanol g⁻¹ _xylitol were obtained. This is because the metabolism of these aerobic yeasts directs the carbon flow to cell growth, while with oxygen limitation it is directed to metabolite production. The HLBS medium was promising for production in the context of a biorefinery. When comparing the two yeasts, S. stipitis presented better ethanol production and P. tannophilus better xylitol production under the conditions that were studied. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd

中文翻译：

---

使用裂殖酵母（Scheffersomyces stipitis）和帕氏乳杆菌（Pachysolen tannophilus）从布鲁尔的废谷物中发酵半纤维素酒，用于生产2G乙醇和木糖醇

啤酒生产产生啤酒厂的废谷物作为副产品。该生物质包含木质素，纤维素和半纤维素，可用于生产第二代（2G）乙醇和木糖醇。为了使其在经济上可行，必须使用可发酵的馏分，以使纤维素和半纤维素转化为乙醇。这项研究评估了使用啤酒白僵菌（Scheffersomyces stipitis）和帕氏索氏单宁（Pachysolen tannophilus）在有氧和氧气有限的条件下发酵啤酒糟（HLBS）中的半纤维素酒的发酵效果。将结果与在复杂培养基（YPX）和基本培养基（MMX）中获得的数据进行比较。在有氧条件下，为S.树干毕赤酵母中的HLBS介质，μ _最大 = 0.12ħ ^-1，Y _{乙醇/木糖} = 0.14，乙醇对木糖醇的选择性（S _{乙醇/木糖醇}）获得3.4 g_乙醇g ^-1 _木糖醇。在氧气受限的条件下，获得了Y _{乙醇/木糖} = 0.22和S _{乙醇/木糖} = 1.17 g_乙醇g ^-1 _木糖醇。为P.鞣管囊酵母，在需氧条件下，将HLBS介质给μ _最大 = 0.08ħ ^-1，和ÿ _{乙醇/木糖} = 0.005，与选择性乙醇超过木糖醇（小号 _{乙醇/木糖醇}）0.12克_乙醇g ^-1 _木糖醇。在氧气受限的条件下，获得了Y _{乙醇/木糖} = 0.09，S _{乙醇/木糖醇} = 0.20 g_乙醇g ^-1 _木糖醇。这是因为这些有氧酵母的代谢将碳流引导至细胞生长，而在氧气受限的情况下，它直接用于代谢产物的产生。HLBS培养基有望在生物精炼厂生产。当比较两个酵母，S.赤酵母呈现更好的乙醇生产和P.鞣管囊酵母在所研究的条件下，木糖醇的产量更高。©2019年化学工业协会和John Wiley＆Sons，Ltd