An efficient and rapid supercritical fluid chromatography (SFC) method was established for the analysis of flavonoids in Citri Reticulatae Pericarpium (CRP), the best conditions were obtained by optimizing the parameters of the SFC method. The peak area obtained by SFC analysis of CRP samples, combined with chemical pattern recognition, was used to establish a model to evaluate the quality of Guang Chenpi (GCP) and Chenpi (CP) in CRP. Partial least squares discriminant analysis (PLS-DA) proved to be an excellent method that can accurately distinguish GCP from CP. The PLS-DA model was established by selecting the training set, and the characteristic components (Didymin and Hesperidin) were screened out to further establish the model, and the testing sets were brought into the model for verification, indicating that the model established based on the peak areas is reliable, and two quality markers (Narirutin and Neohesperidin) were found to distinguish between Xinhui and Non-Xinhui in GCP based on the content determination. In conclusion, the combination of SFC and chemical pattern recognition for the quality evaluation of CRP has great potential.
Citri Reticulatae Pericarpium (CRP), the dried pericarp of Citrus reticulata Blanco, can be divided into “Guangchenpi” (GCP, the dried pericarps derived from Citrus reticulata ‘Chachi’) and “Chenpi” (CP, the dried pericarps derived from other cultivars of Citrus reticulata Blanco). To discriminate between GCP and CP, a simple and reliable high-performance thin-layer chromatography (HPTLC) method was firstly developed to analyze the volatile compound dimethyl anthranilate , and a high-performance liquid chromatography (HPLC) method was established to simultaneously quantify dimethyl anthranilate and three predominant flavonoids (hesperidin, nobiletin and tangeretin) in CRP samples. Both the HPTLC analysis and HPLC-orthogonal partial least squares discrimination analysis (OPLS-DA) indicated that GCP can be effectively distinguished from CP based on analysis of dimethyl anthranilate. Our results indicated that dimethyl anthranilate can be used as a marker compound for discrimination of GCP and CP. This work provided a convenient approach which might be applied for quality evaluation of CRP.
Xiaomin Cao,Kaixin Shi,Yang Xu,Peipei Zhang,Hongyan Zhang,Siyi Pan
The benefits of citrus herbs are strongly associated with their secondary metabolites. In the study, we conducted widely-targeted metabolomics and ultra-high performance liquid chromatography (UPLC) to compare the variability of ingredients in four citrus herbs. In total, we discovered 1126 secondary metabolites, primarily comprising flavonoids, phenolic acids, lignans and coumarins, and alkaloids. Differential metabolites of citrus herbs were searched by multivariate statistical analysis. Notably, Citri Reticulatae Pericarpium contained higher levels of flavonoids, while Zhique and Huajuhong demonstrated a greater abundance of coumarins. Among the flavonoids determined by UPLC, Guangchenpi demonstrated significantly elevated levels of polymethoxyflavones (tangeretin and nobiletin) compared to other citrus herbs. Additionally, we determined their antioxidant capacity (Chenpi > Guangchenpi > Huajuhong > Zhique) using in vitro assays. Finally, we utilized network pharmacology to explore the antioxidant mechanisms and potential pharmacological ingredients, providing a basis for future preventive and therapeutic applications of these metabolites.