黑曲霉-矿物聚集体的形成及其分泌的多糖特性

摘要

[Objective]In order to understand the weathering on potassium-bearing mineral by Aspergillus niger, we studied the formation of A.niger-mineral aggregation and polysaccharide in the revolving and fermenting mode and their role in the process of weathering on potassium-bearing mineral.[Methods]We used four different media to study the morphology of A.niger-mineral aggregation; ultraviolet-visible spectrum ( UV-Vis ) , fourier transform infrared spectrum (IR), gas chromatography( GC) , scanning electron microscopy ( SEM ) and energy dispersive spectrometer ( EDS ) were combined to research the changes of polysaccharide and their significances in the micro-environment forming fungal-mineral aggregation.[Results]A, niger myclia intertwined, adsorbed and bonded mineral powder to form aggregation by the assistance of polysaccharide and other metabolites.After formation of the aggregation, the concentration and structure of polysaccharide were changed significantly.[Conclusion]The changes of polysaccharide would enhance the adsorption on minerals , chelation on metal ions and adsorption on water molecules, which provided a favorable micro-environment for the fungal using mineral nutrients effectively.%[目的]为深入理解黑曲霉(Aspergillus niger)对含钾矿粉的风化作用,研究在旋转发酵方式下形成的黑曲霉-矿物聚集体及其多糖,并分析它们在含钾矿粉风化过程中的作用.[方法]采用不同组合培养基,研究黑曲霉-矿物聚集体的形成和形貌;联合紫外-可见分光光谱(UV-Vis)、傅立叶变换红外光谱(FT-IR)、气相色谱(GC)、电子扫描显微镜(SEM)、x射线能谱仪(EDS)等分析手段研究黑曲霉-矿物聚集体形成前后微环境中多糖的变化以及这种改变对风化产生的意义.[结果]黑曲霉菌丝与矿粉在多糖等代谢产物帮助下,通过相互缠绕、吸附、粘合等作用形成黑曲霉-矿物聚集体,聚集体形成前后多糖浓度和多糖结构均发生显著改变.[结论]含钾矿粉诱导黑曲霉多糖结构发生明显变化并且浓度增大,这种改变可促进多糖对矿物颗粒的吸附,有助于螯合金属离子和吸附水分子,从而为真菌有效利用矿物营养提供有利的微环境.