食药用真菌多糖具有抗肿瘤、抗病毒、免疫调节、抗凝血、降血脂、延缓衰老等重要的生物活性。然而，低产率限制了食药用真菌多糖生物合成的工业化。显著提高产率的必要前提是阐明影响食药用真菌多糖生物合成的内在机理，而研究多糖生物合成与细胞内pH的关系是阐明影响食药用真菌多糖生物合成内在机理的关键。由此可见，本项目研究不仅科学问题明确，而且具有重要的理论意义。本项目研究内容富有创新，特色鲜明：设计、构建基于碳量子点的新型pH比率荧光探针，利用该类探针建立准确、动态、无损伤地测定食药用真菌细胞内pH的新方法；通过胞外环境宏观调控食药用真菌多糖的生物合成，利用所建立的测定细胞内pH新方法对调控过程中真菌细胞内pH进行动态测定，考察食药用真菌多糖生物合成与细胞内pH的关系。本项目创新性地利用材料学、化学的新观点和新方法研究食药用真菌中的基础科学问题，有望取得重要的研究成果。

Polysaccharides isolated from edible and medicinal fungi have exhibited many important bioactivities such as antitumor, immune modulatory, anticoagulation, lowering blood lipids and anti-aging effects. However, the industrialization of polysaccharide biosynthesis by edible and medicinal fungi is subject to low yield because their biosynthesis mechanism is still unclear. Thus clear mechanism of polysaccharide biosynthesis is very important to help effectively improving yields of polysaccharides. It is supposed that polysaccharide biosynthesis should be closely related to intracellular pH because intracellular pH is an important factor to regulate all the biological reactions in living cells. Therefore, the aim of the current project is firstly to develop a new method of intracellular pH measurements for edible and medicinal fungi cells with high selectivity and sensitivity, and the key of the method is to synthesize new pH ratio fluorescent probes based on carbon dots. Secondly, polysaccharide biosynthesis will be regulated by means of extracellular condition alterations, and then the change of intracellular pH along with the regulation will be dynamically measured by the method of intracellular pH measurement being developed in this project. Consequently, the relationship between the biosynthesis of polysaccharides and intracellular pH will be finally elucidated. It is of scientific interest that the current project will provide theoretical and experimental basis for understanding the mechanism of polysaccharide biosynthesis in fungi cells. Wonderful results will be achieved when basic scientific research on edible and medicinal fungi is performed creatively using the new ideas and methods of material science and chemistry.