利用代谢组学技术研究2, 4-二氯苯氧乙酸保鲜柑橘的作用机理

2, 4-二氯苯氧乙酸（2, 4-D）是柑橘采后贮藏中重要的保鲜剂，但其安全性仍存争议，寻找天然高效保鲜剂是柑橘采后面临的重要问题。前期转录组和蛋白组研究表明，2, 4-D处理柑橘果实后持续诱导大量代谢相关基因和蛋白表达，暗示了处理后代谢产物的组分和含量也可能发生改变，但缺乏相关实验研究。本项目拟以纽荷尔脐橙（Citrus sinensis osbeck ‘newhall’）为材料，利用GC-MS、HPLC-MS、GC、HPLC研究2, 4-D处理后果实不同组织（黄皮层、白皮层和果肉）中初生代谢产物和次生代谢产物在8个贮藏时期的组分和含量差异。进一步通过生物信息学的统计和聚类方法深入挖掘数据，获得决定2, 4-D保鲜作用的关键组织部位、关键时期和关键代谢产物。通过此研究能够了解2,4-D的保鲜作用机理，同时为筛选安全有效的2, 4-D天然替代品提供科学依据。

2, 4-Dichlorophenoxyaceatic acid (2, 4-D) is an important preservative to keep the quality of postharvest citrus fruit, however, it is controversial for using of 2, 4-D to postharvest handling. Hence, searching for natural and high effective preservatives is an important issue to be resolved in citrus postharvest industry. Previous transcriptomic and proteomic researches showed that the expression of abundant metabolism related genes and proteins in citrus fruit were induced by 2, 4-D treatment, this result indicates that the ingredients and contents of metabolites in fruit would be changed by 2, 4-D, but it is lack of experimental proof. In this project, ‘Newhall’ orange (Citrus sinensis osbeck ‘newhall’) will be selected as experimental material, and GC-MS and GC, HPLC-MS and HPLC will be used to identify the difference in the components and contents of primary metabolites and secondary metabolites in tissues of flavedo, albedo and fresh between control and 2,4-D treatment at 8 periods after treatment. Data mining of the metabolomics profiling will be performed by methods of statistical and cluster used in bioinformatics analysis to obtain the key tissue and period and pivotal metabolites in the process of quality maintenance by 2, 4-D. The results of this project will furtherly illuminate the mechanism upon 2, 4-D preserving citrus fruit postharvest quality and provide theoretical bases for searching natural and high effective preservatives.