Analysis of Differences in Flavonoid Components between Citri Reticulatae Pericarpium from Citrus reticulata Blanco cv. Zhangshuensis and Its Parents Using Liquid Chromatography-Mass Spectrometry Combined with Multivariate Statistical Analysis

To analyze the chemical components of the dried mature pericarps (Citri Reticulatae Pericarpium, Chenpi in Chinese) of Citrus reticulata cv. Zhangshuensis (Zhangtouhong) and its two parental species, ‘Sanhu’ tangerine (Citrus reticulata Blanco cv. ‘Sanhu’) and Aurantii Fructus, and to elucidate the material basis for the health benefits of Chenpi in order to provide a reference for understanding the origin of Zhangtouhong from a chemotaxonomical perspective.

The chemical components of Zhangtouhong Chenpi, Sanhu Chenpi and Aurantii Fructus were analyzed using liquid chromatography-mass spectrometry (LC-MS). Multivariate statistical analysis was employed to identify differential flavonoid components between Zhangtouhong Chenpi and its parental species, including principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). Cluster heatmap analysis, boxplot analysis, correlation analysis, and pathway enrichment analysis were conducted for this purpose.

A total of 114 components were identified, and 30 differential components were selected, including 28 flavonoid compounds. In Zhangtouhong Chenpi, the predominant flavonoids were identified to be sinensetin, 6-demethoxytangeretin, and 3,5,6,7,8,3’,4’-heptamethoxyflavone, all of which belonged to the polymethoxyflavone subclass and a strong correlation existed among their contents. In Aurantii Fructus, the predominant flavonoids were identified to be rhofolin, naringin, naringenin, and poncirin, each of which was substituted in the 5,7, and 4’ positions of the mother nucleus. Additionally, a comprehensive analysis of the biosynthetic pathways of these flavonoids was conducted.

This method enables rapid and accurate analysis of the chemical constituents of Citrus reticulata cv. Zhangshuensis and its parental species, providing a scientific basis understanding the origin of Citrus reticulata cv. Zhangshuensis as a specialty cultivar in Jiangxi.