Evaluation of the quality of Fructus Aurantii using HPLC fingerprinting combined with multimodal chemometric methods
Citrus aurantium L. and its cultivated varieties, including Citrus aurantium ‘huangpi’, C. aurantium ‘daidai’, C. aurantium ‘zhuluan’, and C. aurantium ‘tangcheng’, are dried immature fruits of the Rutaceae family’s Citrus genus. They are harvested in July when the skin is still green. Citrus aurantium has a slightly cold nature, with a bitter, pungent, and sour taste. It has the function of regulating qi and promoting stagnation and reducing bloating. According to their distribution regions and main cultivated varieties, Chinese Citrus aurantium can be divided into four categories: Hunan Citrus aurantium, Sichuan Citrus aurantium, Jiang Citrus aurantium, and Zhejiang Citrus aurantium (Su Citrus aurantium and Wen Citrus aurantium). The main native plant of Xiangzhi shell is Huangpi sour orange; The main native plant of Sichuan Citrus aurantium is sour orange; The main native plant of Fructus Aurantii is stinky orange; The original plant of Su Zhi shell is Dai Dai sour orange (Dai Dai flower); The original plant of Fructus Aurantii immaturus is Zhuluan. The chemical components of Fructus Aurantii are mainly flavonoids, volatile oils, coumarins, and a small amount of alkaloids. Flavonoids are the main active ingredients of Fructus Aurantii, and dihydroflavonoids represented by naringin and neohesperidin play important roles in pharmacological effects, such as antioxidant, anti-inflammatory, antibacterial, and improvement of gastrointestinal motility disorders. The content of naringin and neohesperidin in Fructus Aurantii from different regions varies.

There are many varieties of Fructus Aurantii, which are affected by factors such as origin, harvesting time, and storage conditions, resulting in significant differences in their active ingredients and content. The quality of Fructus Aurantii commercial medicinal materials on the market is unstable, which directly affects the clinical efficacy of Fructus Aurantii. At present, the quality control of Fructus Aurantii mainly focuses on the determination of naringin and neohesperidin content. Through literature review, it can be seen that most methods for determining the content of naringin and neohesperidin are established using high-performance liquid chromatography. Considering the complexity and diversity of active ingredients in traditional Chinese medicine, naringin and neohesperidin as detection indicators for Fructus Aurantii are no longer comprehensive enough to meet the increasingly high requirements of social development for drug quality control. The fingerprint of traditional Chinese medicine is a comprehensive analysis method that uses characteristic chromatograms or spectrograms to characterize its chemical characteristics as a whole. It is currently recognized as one of the most effective technical means for comprehensively evaluating the overall quality of traditional Chinese medicine. This study established high-performance liquid chromatography (HPLC) fingerprint spectra of 11 Fructus Aurantii medicinal materials, determined the content of 13 chemical components, and comprehensively evaluated their quality using multimodal stoichiometry, aiming to provide reference for the quality evaluation and control of Fructus Aurantii medicinal materials.

 

This experiment used HPLC to establish fingerprint spectra of 11 samples of Fructus Aurantii, and combined quantitative analysis, similarity evaluation, principal component analysis, and discriminant analysis to evaluate the quality of the 11 samples. This method is simple and accurate, and can be used for comprehensive quality evaluation of Fructus Aurantii. The quality percentage of naringin and neohesperidin in Fructus Aurantii from different regions is high; The HPLC fingerprint spectrum has 16 common peaks, and 11 samples of Fructus Aurantii have good similarity. The quality of Fructus Aurantii from different origins is relatively stable; According to the comprehensive score ranking results, the citrus peel produced in Xiangtan, Hunan has a high comprehensive score, indicating that its quality is relatively good; From the VIP value results, it can be seen that four quality markers, namely naringin, yunxiang naringin, hesperidin, and kumquat glycoside, were screened based on VIP values greater than 1.