State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai, 201620, China.
China-Sweden Associated Research Laboratory in Industrial Biotechnology, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China.
Microb Cell Fact. 2017 Dec 21;16(1):229. doi: 10.1186/s12934-017-0846-y.
Through pretreatment and enzymatic saccharification lignocellulosic biomass has great potential as a low-cost feedstock for production of bacterial nanocellulose (BNC), a high value-added microbial product, but inhibitors formed during pretreatment remain challenging. In this study, the tolerance to lignocellulose-derived inhibitors of three new BNC-producing strains were compared to that of Komagataeibacter xylinus ATCC 23770. Inhibitors studied included furan aldehydes (furfural and 5-hydroxymethylfurfural) and phenolic compounds (coniferyl aldehyde and vanillin). The performance of the four strains in the presence and absence of the inhibitors was assessed using static cultures, and their capability to convert inhibitors by oxidation and reduction was analyzed.
Although two of the new strains were more sensitive than ATCC 23770 to furan aldehydes, one of the new strains showed superior resistance to both furan aldehydes and phenols, and also displayed high volumetric BNC yield (up to 14.78 ± 0.43 g/L) and high BNC yield on consumed sugar (0.59 ± 0.02 g/g). The inhibitors were oxidized and/or reduced by the strains to be less toxic. The four strains exhibited strong similarities with regard to predominant bioconversion products from the inhibitors, but displayed different capacity to convert the inhibitors, which may be related to the differences in inhibitor tolerance.
This investigation provides information on different performance of four BNC-producing strains in the presence of lignocellulose-derived inhibitors. The results will be of benefit to the selection of more suitable strains for utilization of lignocellulosics in the process of BNC-production.
通过预处理和酶解，木质纤维素生物质作为生产细菌纳米纤维素（BNC）的低成本原料具有很大的潜力，BNC 是一种高附加值的微生物产品，但预处理过程中形成的抑制剂仍然是一个挑战。在本研究中，比较了三种新的 BNC 生产菌株对木质纤维素衍生抑制剂的耐受性与 Komagataeibacter xylinus ATCC 23770 的耐受性。研究的抑制剂包括呋喃醛（糠醛和 5-羟甲基糠醛）和酚类化合物（松柏醛和香草醛）。使用静态培养评估了四种菌株在存在和不存在抑制剂时的性能，并分析了它们通过氧化和还原转化抑制剂的能力。
尽管两种新菌株对呋喃醛的敏感性高于 ATCC 23770，但其中一种新菌株对呋喃醛和酚类化合物均表现出较高的抗性，并且还表现出较高的体积 BNC 产量（高达 14.78±0.43g/L）和消耗糖的 BNC 产量（0.59±0.02g/g）。抑制剂被菌株氧化和/或还原，毒性降低。四种菌株在抑制剂的主要生物转化产物方面表现出很强的相似性，但转化抑制剂的能力不同，这可能与抑制剂耐受性的差异有关。
本研究提供了关于四种 BNC 生产菌株在木质纤维素衍生抑制剂存在下不同性能的信息。研究结果将有助于在 BNC 生产过程中选择更适合利用木质纤维素的菌株。
