Zwirzitz Alexander, Alteio Lauren, Sulzenbacher Daniel, Atanasoff Michael, Selg Manuel
Biosciences Research Group, University of Applied Sciences Upper Austria, Stelzhamerstraße 23, 4600 Wels, Austria.
Centre of Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, Division of Terrestrial Ecosystem Research, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
J Fungi (Basel). 2021 Feb 6;7(2):121. doi: 10.3390/jof7020121.
The interest in using non-conventional yeasts to produce value-added compounds from low cost substrates, such as lignocellulosic materials, has increased in recent years. Setting out to discover novel microbial strains that can be used in biorefineries, an strain was isolated from waste cooking oil (WCO) and its capability to produce ethanol from wheat straw hydrolysate (WSHL) was analyzed. As with previously isolated strains, WCO- KJ27-7 is thermotolerant. It grows well at elevated temperatures up to 42 °C. Furthermore, spot drop tests showed that it is tolerant to various chemical fermentation inhibitors that are derived from the pre-treatment of lignocellulosic materials. KJ27-7 is particularly tolerant to acetic acid (up to 75 mM) and tolerates 10 mM formic acid, 5 mM furfural and 10 mM hydroxymethylfurfural. Important for biotechnological cellulosic ethanol production, KJ27-7 grows well on plates containing up to 10% ethanol and media containing up to 90% WSHL. As observed in shake flask fermentations, the specific ethanol productivity correlates with WSHL concentrations. In 90% WSHL media, KJ27-7 produced 10.3 g L ethanol within 24 h. This corresponds to a product yield of 0.50 g g glucose (97% of the theoretical maximum) and a volumetric productivity of 0.43 g L h. Therefore, KJ27-7 is an efficient producer of lignocellulosic ethanol from WSHL.
近年来，利用非常规酵母从低成本底物（如木质纤维素材料）生产增值化合物的兴趣有所增加。为了发现可用于生物精炼厂的新型微生物菌株，从废食用油（WCO）中分离出一株菌株，并分析了其从麦秸水解物（WSHL）生产乙醇的能力。与先前分离的菌株一样，WCO-KJ27-7具有耐热性。它在高达42°C的高温下生长良好。此外，点滴试验表明，它对源自木质纤维素材料预处理的各种化学发酵抑制剂具有耐受性。KJ27-7对乙酸（高达75 mM）具有特别的耐受性，并且耐受10 mM甲酸、5 mM糠醛和10 mM羟甲基糠醛。对于生物技术纤维素乙醇生产而言重要的是，KJ27-7在含有高达10%乙醇的平板和含有高达90%WSHL的培养基上生长良好。如在摇瓶发酵中观察到的，特定乙醇生产率与WSHL浓度相关。在90%WSHL培养基中，KJ27-7在24小时内产生了10.3 g/L乙醇。这相当于0.50 g/g葡萄糖的产物产率（理论最大值的97%）和0.43 g/L/h的体积生产率。因此，KJ27-7是从WSHL生产木质纤维素乙醇的高效生产者。
