陈皮是广东特色药食两用资源，具有年份越陈功效越佳的特点。申请人前期研究发现高温高湿、黑曲霉转化均有利于促进陈皮活性物质多甲氧基黄酮（PMFs）含量的上升，推测高温高湿通过加速黑曲霉的转化作用促进陈皮中PMFs的形成，但其具体机制尚不清楚。本项目以前期鉴定的具有促PMFs形成功能的黑曲霉菌株为研究对象，拟通过分析不同温湿度下黑曲霉对陈皮黄酮类底物的转化规律，明确其促进PMFs形成的反应途径，明确差异代谢物；采用RNA-seq测序检测转化过程中菌体的基因表达情况，并对差异表达基因和差异代谢物进行联合分析，探明参与PMFs形成的关键基因；最后在陈皮内检测相关酶活以及关键基因的表达，进一步揭示黑曲霉转化形成PMFs相关的基因和酶，从基因和蛋白水平阐明高温高湿促进黑曲霉转化陈皮黄酮介导的PMFs形成机制，为陈皮陈化品质调控提供理论依据。

As a traditional medicine and food resource of Guangdong province, Pericarpium Citri Reticulatae (CRP, “Chenpi” in Chinese) has the characteristics of that the longer they are stored, the better quality of the end product. Previously, we found that both high temperature and high humidity and Aspergillus niger transformation were conducive to promoting the increase of the polymethoxyflavone (PMFs) content in CRP. It was speculated that high temperature and high humidity promoted the formation of PMFs in CRP by accelerating A. niger transformation, but the specific mechanism was unclear yet. In this project, A. niger strains that have been identified with the function of promoting the formation of PMFs were taken as the research objects. By analyzing the transformation characteristics of A. niger to CRP flavonoid extract under different temperature and humidity, the reaction pathway of promoting the formation of PMFs and the differential metabolites will be deduced. RNA-seq sequencing was used to detect the gene expression of the A. niger transcriptome during the transformation process, and the differential expression genes were identified. Then combined analysis of the differential metabolites and differential genes were carried out to find the key genes involved in the formation of PMFs. Finally, the relevant enzyme activity and the expression of key genes were detected in CRP to further reveal the genes and enzymes related to A. niger biotransformation from CRP flavonoids to PMFs. And then the mechanism of high temperature and high humidity promoting the biotransformation of A. niger from CRP flavonoids to PMFs was clarified on the gene and protein levels, to provide a theoretical basis for quality control of CRP aging.