Study on the changes in components of Fructus Evodiae and processed Fructus Evodiae using UPLC fingerprinting combined with multivariate statistical analysis
Wu Zhuyu, first recorded in the Shennong Bencao Jing, is classified as a medium grade. Eucommia rutaecarpa (Juss.) Benth. is a plant in the Rutaceae family Euodia rutaecarpa (Juss.) Benth Var. officinalis (Dode) Huang or Euodia rutaecarpa (Juss.) Benth Dry near mature fruit of var. bodinieri (Dode) Huang. When the fruit has not yet cracked from August to November, cut off the fruit branches, dry them in the sun or at low temperatures, and remove impurities such as branches, leaves, and stems. Wu Zhuyu has the effects of dispelling cold and relieving pain, reducing reflux and stopping vomiting, and helping yang and stopping diarrhea. It is clinically used for treating symptoms such as Jueyin headache, cold hernia and abdominal pain, cold and damp athlete’s foot, menstrual abdominal pain, abdominal distension and pain, vomiting and acid swallowing, and diarrhea in the five seasons. Modern research has shown that Fructus Evodiae has various effects such as vasodilation, anti-inflammatory, analgesic, antibacterial, central protection, antiemetic, and antiemetic properties. The pharmacological effects of Fructus Evodiae and its processed licorice juice (hereinafter referred to as “processed Fructus Evodiae”) are different, which may be related to the changes in chemical composition before and after processing of Fructus Evodiae. After processing with licorice juice, Wu Zhuyu can reduce its toxicity and alleviate dryness.
There are numerous chemical components and complex pharmacological activities in Evodia rutaecarpa. Its main chemical components include alkaloids, bitters, flavonoids, and volatile oils. Due to the diversity and complexity of chemical components in traditional Chinese medicine, a single component quantitative chemical component quality control model not only lacks specificity, but also struggles to reflect the inherent quality attributes of traditional Chinese medicine. Therefore, it is necessary to accurately explain the changes in various components of Wu Zhu Yu and its processed Wu Zhu Yu, summarize the patterns of changes in pharmacological components before and after processing, in order to more comprehensively explain the differences in pharmacological activity and clinical effects. In recent years, the emergence of a large number of new instruments and technologies has made fingerprint and chemical pattern recognition the mainstream of quality research in traditional Chinese medicine. The combination of fingerprint and chemometric analysis methods provides a new idea for the overall quality control of traditional Chinese medicine.
This study used ultra-high performance liquid chromatography (UPLC) technology to establish fingerprint spectra of Fructus Evodiae and processed Fructus Evodiae. Combined with similarity evaluation and multivariate statistical analysis methods such as cluster analysis (CA) and orthogonal partial least squares discriminant analysis (OPLS-DA), a comprehensive evaluation was conducted to analyze the differential components of Fructus Evodiae before and after processing from multiple perspectives. The correlation between the pharmacological effects and chemical composition of Fructus Evodiae and processed Fructus Evodiae was preliminarily explored, and to some extent, the relationship between the changes in pharmacological effects and chemical composition of Fructus Evodiae before and after processing was explained. This can provide data reference for the quality and processing research of Fructus Evodiae.

 

The establishment of the fingerprint spectrum of Evodia rutaecarpa can not only provide a preliminary evaluation of the quality of Evodia rutaecarpa from different production areas, but also clearly distinguish it from processed Evodia rutaecarpa. The fingerprint spectrum of Evodia rutaecarpa identifies a total of 27 common chromatographic peaks, and the newly added common chromatographic peak 28 in processed Evodia rutaecarpa is glycyrrhizic acid, which is produced after processing Evodia rutaecarpa. This peak can be used to clearly distinguish between raw and processed Evodia rutaecarpa products. The similarity evaluation results show that, except for 4 batches of samples from Jiangxi production areas, the fingerprint spectra of Evodia rutaecarpa from other production areas have high similarity. One batch of similarity anomalies occurred in the Hunan production area, which may be related to differences in harvesting time and processing methods in the production area. Six differential biomarkers were identified using orthogonal partial least squares discriminant analysis (OPLS-DA), and their significance was ranked as glycyrrhetinic acid>evodiamine>peak 3>peak 1>chlorogenic acid>peak 2.
According to traditional Chinese medicine theory, the Chinese medicine Wu Zhu Yu has the properties of heat, bitterness, and cold, and has the functions of dissipating heat, relieving pain, reducing reflux, and stopping nausea. It is used to treat symptoms such as headache or epigastric pain caused by liver and stomach deficiency and cold, yin turbidity and upward reflux. Licorice has a mild nature and a sweet taste, which has the effects of tonifying the spleen, nourishing qi, relieving pain, and harmonizing various medicines. Therefore, after being roasted with licorice juice, Wu Zhuyu can reduce toxicity and alleviate dryness to a certain extent, making it suitable for people with weak spleen and stomach. After processing with licorice juice, in addition to increasing glycyrrhetinic acid, the average peak area of the other five differential markers in Wu Zhu Li showed a decreasing trend. Reports have indicated that Wu Zhu Li alkaloid, Wu Zhu Li sub alkaloid, and limonin have certain toxic effects on human embryonic kidney cells. Therefore, the decrease in the content of chemical components such as Wu Zhu Li alkaloid after processing is one of the reasons for the reduced toxicity of Wu Zhu Li processing. There are also studies indicating that different components of Evodia rutaecarpa have toxicity, with a strength of volatile oil>whole component>alcohol extract component>water extract component. Therefore, during the processing of Evodia rutaecarpa, the content of volatile oil decreases due to heat, which weakens its toxicity. At the same time, phenolic acid components such as chlorogenic acid decrease in content due to thermal instability, making the efficacy of Evodia rutaecarpa more gentle.
This study used ultra-high performance liquid chromatography (UPLC) to establish fingerprint spectra of Fructus Evodiae and processed Fructus Evodiae. This method has strong specificity and good repeatability, and preliminarily explored the correlation between the pharmacological effects and chemical composition of Fructus Evodiae and processed Fructus Evodiae. To a certain extent, it explained the relationship between the changes in pharmacological effects and chemical composition before and after processing of Fructus Evodiae, which can provide data reference for the quality and processing research of Fructus Evodiae.