云南木姜子抗菌成分及其分子作用机制研究
批准号:
32060520
项目类别:
地区科学基金项目
资助金额:
35.0 万元
负责人:
薛桥丽
依托单位:
学科分类:
食品原料学
结题年份:
2024
批准年份:
2020
项目状态:
已结题
项目参与者:
薛桥丽
中文摘要
天然、高效、广谱、安全抗微生物剂是国际研究热点。木姜子高效抗流感病毒、抗菌效应已被民间和实践证实,但其主体抗菌成分(LAC)及分子作用机理迄今尚无报道。本项目拟在前期基础上采用极性不同溶剂及色谱柱集成技术对云南木姜子逐级分离,同时配合高通量筛选技术追踪抗菌成分。运用UHPLC-MS、NMR等波谱技术并结合理化分析探明LAC组成。采用光谱结构解析、SEM等分析菌体结构变化;运用免疫共沉淀技术确定LAC对靶标菌DNA合成的影响,采用蛋白质组学、生物信息手段、圆二色谱确定LAC与DNA结合位点和高级构象的变化,从基因水平揭示LAC对遗传物质的作用机制。基于蛋白组学、差异蛋白Pathway富集分析,阐释LAC作用靶点和作用机制;采用生物信息学从分子转录水平上揭示LAC对代谢通路、呼吸作用的影响机制,阐明LAC分子作用机制。为云南木姜子作为潜在天然抗菌剂的深度开发和利用提供理论基础和科学依据。
英文摘要
Exploitation of natural, high-efficiency, broad-spectrum, safe antibacterial have received much attention in all countries. The high-efficiency anti-influenza virus and antibacterial effects of Litsea yunnanensis Yang et P. H. Huang have been confirmed by folk and practice, but its antibacterial components(LAC) and its molecular mechanism have not been reported so far. Based on the previous research, this project plans to further separate the Litsea yunnanensis Yang et P. H. Huang by using different polar solvents and column integration technology, and at the same time, with high-throughput screening technology to track active antibacterial components. The antibacterial monomer compounds were identified by UHPLC-MS and NMR spectroscopy techniques combined with physical and chemical analysis to determine the composition and structure of LAC. Spectral structure analysis and in situ SEM are used to analyze the changes of bacterial structure; and immunoco-precipitation technology is used to determine the effect of LAC on the DNA synthesis of target bacteria; and proteomics, bioinformatics and circular dichroism are used to determine the binding site of LAC and DNA And higher-level conformational changes, which reveals the mechanism of action of LAC on genetic material at the genetic level. Based on proteomics and differential protein pathway enrichment analysis, the target and mechanism of action of LAC are explained; and the bioinformatics is used to reveal the mechanism of LAC's influence on metabolic pathways and respiration at the molecular transcription level, which clarifies the molecular mechanism of LAC. The research results provide theoretical basis and scientific basis for the deep development and utilization of Litsea yunnanensis Yang et P. H. Huang as a potential natural antibacterial agent.
木姜子作为高效、无毒、安全天然食品调味剂和防腐剂广泛应用于云南餐饮食品中。本项目以云南木姜子为研究对象,在系统评价不同极性木姜子提取物体外抑菌效应基础上,利用萃取、薄层层析、正相、反相硅胶柱层析等现代天然产物分离和现代波谱技术解析抗菌活性成分结构,并分析抗菌成分对靶细胞膜通透性、形态、代谢、核酸、蛋白质结构等变化来诠释其抗菌作用机理。主要研究结果为:木姜子55%乙醇提取物(EELC)对S. aureus抑制效果最佳,其抑菌圈及MIC分别为18.25±0.26 mm、19μg/mL;木姜子75% EELC对E.coil抑制效果最佳,抑菌圈及MIC分别为17.81±0.71 mm、819 μg/mL。55%及75% EELC在热处理、加热时间、酸碱处理及紫外光照射件下均具有良好的抑菌稳定性。55%、75% EELC均能够维持鱼肉新鲜度及抑制鱼肉中腐败微生物的生长;木姜子石油醚提取物经自显影活性追踪及波普鉴定,主要抗菌物质为月桂酸,其对S. aureus, L. monocytogenes, B. cereus, E. faecalis, V. parahaemolyticus, S. flexneri均具有良好的抗菌活性。月桂酸与挥发性主体抗菌物质柠檬醛具有协同抗菌效果,二者协同对细菌细胞壁、膜造成损伤,引起胞内物质泄露、膜电位及离子平衡被打破;对细胞能量物质产生和代谢产生抑制,抑制以TCA循环为代表的细胞呼吸途径,并对细胞产生氧化应激胁迫;降低细菌胞内蛋白及基因组DNA含量,并与基因组DNA发生可逆结合,影响核酸代谢;抑制生物膜形成,降低细胞疏水性、自聚性及运动性,可降解生物膜并对生物膜内细菌进行杀灭。对细菌胞内涉及氨基酸生物合成、物质转运、氨酰tRNA生物合成、核苷酸代谢等代谢通路造成抑制。本项目结果为潜在食品抗菌剂的研究提供可行性,为云南木姜子资源深度开发和高效利用提供理论基础和科学依据。本项目培养研究生5人,已发表论文6篇,其中SCI论文1篇,EI1篇。
国内基金
海外基金