米根霉利用木糖与葡萄糖的代谢差异

Metabolism of Rhizopus oryzae with xylose or glucose as carbon resource

摘要:

摘要: 【目的】木质纤维素是世界上储量最丰富、最廉价的可再生生物质资源，以米根霉为研究对象，探讨对木质纤维素中主要单糖成分——木糖和葡萄糖的代谢差异，为木质纤维素的高效利用提供科学依据。【方法】分别以木糖和葡萄糖为碳源，考察米根霉的生物量、细胞大分子组分、胞内还原力(NADH/NAD+)、ATP含量以及有机酸积累的差异。【结果】以木糖为碳源时，米根霉生物量较高，达到9.93g/L，对糖转化率达37.2%，同时胞内还原力(NADH/NAD+)和ATP含量较高，几乎不积累有机酸；以葡萄糖为碳源时，米根霉生物量

Abstract:

Abstract: [Objective] As one of the most abundant and cheapest recyclable bio-resources, cellulosic biomass appear to be the promising new energy if the two major components, glucose and xylose, are efficiently used. [Methods] We compared the metabolism of Rhizopus oryzae growing on glucose or xylose. We measured biomass accumulation, intercellular metabolite contents, and organic acids production. [Results] When cultured on xylose, the rate of bio-transformation reached 35.2% compared to 24.3% in the glucose. Intercellular contents accumulated much more by using xylose as sole carbon than using glucose. However, the quantity of organic acid was less with xylose than with glucose. In addition, the NADH/NAD+ and ATP quantity also differed. [Conclusion] With our data analysis, solution is suggested to the all-around utilization of the cellulous in the fermentation industry, which means increasing biomass by xylose at first stage, and producing organic acids or other ferment products at the second stage. Such suggestion may be a reasonable guideline to the economic application of the cellulosic material in the near future.