Faculty of Agriculture, University of Miyazaki, 1-1, Gakuen-kibanadai-nishi, Miyazaki, 889-2192, Japan.
Graduate School of Agriculture and Engineering, University of Miyazaki, 1-1, Gakuen-kibanadai-nishi, Miyazaki, 889-2192, Japan.
Appl Biochem Biotechnol. 2020 Nov;192(3):895-909. doi: 10.1007/s12010-020-03375-x. Epub 2020 Jul 1.
In efforts to lower the cost of total conversion of lignocellulosic materials, utilization of hemicellulose must be considered. White-rot fungus Phlebia sp. MG-60 can produce ethanol directly from cellulose and has fermentation ability for glucose, cellulose, and xylose. Therefore, white-rot fungi can be considered a good candidate for consolidated bioprocessing to give bioethanol from lignocellulosic biomass, although little information is available on the direct fermentation of xylan. In the present study, some Phlebia species were selected as candidates because of their ability to ferment xylose to ethanol more efficiently than Phlebia sp. MG-60. This process indicated that the basidiomycetes that can produce ethanol from xylose are closely related genetically within the Phlebia genus. The selected Phlebia species showed higher ethanol productivity from corn core and beechwood xylans than Phlebia sp. MG-60. The ethanol yields from corn core xylan in culture with Phlebia acerina HHB11146, Phlebia ludoviciana HHB9640, and Phlebia subochracea HHB8494 were 46.2%, 46.7%, and 39.7% of theoretical maximum, and those from beechwood xylan were 19.09%, 17.7%, and 21.4% of the theoretical maximum, respectively.
为了降低木质纤维素材料全转化的成本，必须考虑半纤维素的利用。白腐菌 Phlebia sp. MG-60 可以直接从纤维素生产乙醇，并且具有发酵葡萄糖、纤维素和木糖的能力。因此，白腐菌可以被认为是用于从木质纤维素生物质生产生物乙醇的综合生物加工的良好候选物，尽管关于木聚糖的直接发酵的信息很少。在本研究中，选择了一些 Phlebia 物种作为候选物，因为它们比 Phlebia sp. MG-60 更有效地发酵木糖生产乙醇。这一过程表明，能够从木糖生产乙醇的担子菌在 Phlebia 属内具有密切的遗传关系。所选 Phlebia 物种从玉米芯和山毛榉木聚糖生产乙醇的生产力高于 Phlebia sp. MG-60。在 Phlebia acerina HHB11146、Phlebia ludoviciana HHB9640 和 Phlebia subochracea HHB8494 的培养物中，玉米芯木聚糖的乙醇得率分别为理论最大值的 46.2%、46.7%和 39.7%，山毛榉木聚糖的乙醇得率分别为理论最大值的 19.09%、17.7%和 21.4%。
