预发酵椰子水的微生物菌相解析及促进细菌纤维素合成的机理

细菌纤维素（BC）在食品、医药、材料等领域应用广泛，一直是热点。商业生产主要以椰子水为原料，但海南现遇到产量不稳导致成本升高的瓶颈。本项目首次提出先解析椰子水预发酵过程微生物菌相结构，再阐明预发酵椰子水能比新鲜椰子水显著促进BC合成的作用机理。首先以传统手段分析预发酵椰子水中可培养微生物菌相结构及变化，再以高通量测序和定量PCR综合分析全部微生物菌相结构和优势菌种及变化，然后对优势菌种逐一筛选，选出能显著促进BC合成的关键菌株/组合；藉此以关键菌株为研究模型，通过基于核磁共振分析（CPMG 1H-NMR）的代谢组学研究，解析预发酵椰子水中的差异代谢物，剖析其与BC合成调控间的相关关系，再综合菌相变化分析结果，清晰阐明预发酵椰子水促进BC合成的作用机理。这一方面可为建立“预发酵新技术”、解决生产技术瓶颈而提供理论指导，同时可为基于差异代谢物而进一步深入研究BC的代谢调控机制提供新的研究思路。

Bacterial cellulose is widely used in such areas as food industry, medicine, materials and so on, and has been the hotspot for research. BC is usually produced from naturally fermented coconut water commercially and now faces the bottleneck due to unstable production and low yield in Hainan, China. In this project, we will investigate the culturable microorganisms and their dynamical changes in the prefermented coconut water using traditional method, and also analyze the microbiota structure and evolution in the prefermented coconut water by using high-throughput sequencing and quantitative PCR. Then we will select the predominant microbes in the prefermented coconut water and the key strain or strains to enhance BC biosynthesis significantly. With the key strain(s) as the model, we will study the metabolics of the fermented coconut water using CPMG 1H-NMR and analyze the difference of metabolites in the fermented coconut water and the fresh coconut water, and then study the correlation between the different metabolites and the BC biosynthesis and regulation, and elucidate the mechanism of prefermented coconut water to enhance BC biosynthesis significantly. This project will supply a theoretical guide for controlled prefermentation of coconut water and to solve the bottle neck for BC production in China, and also supply a new approach to study the mechanism for BC metabolism regulation based on the different metabolites.