Analyses of Physical and Chemical Compositions of Different Medicinal Specifications of CRPV by Use of Multiple Instrumental Techniques Combined with Multivariate Statistical Analysis

Quality difference analysis of raw and vinegar-processed products of Qingpi based on color and component correlation

The dried young fruit of Citrus reticulata Blanco, known as Qingpi, is commonly used in clinic both with its raw and vinegar-processed products. However, the distinctions in quality between these two products remain unclear, and the methods for identification are considerably intricate. In this study, an electronic eye technique was applied to assess the overall color of Qingpi products before and after processing. The luminosity (L*) and yellow-blue (b*) values of Qingpi decreased after vinegar processing, while red-green (a*) values increased. The discriminant function models based on color parameters were established to effectively classify the two products. The chemical compositions of different Qingpi products were characterized using ultra-high performance liquid chromatography fingerprint technology, and 10 distinct components were considered as potential chemical markers. The correlation analysis revealed a significant relationship between chromatic values and chemical components. In conclusion, the results of this study suggested that chromaticity can be effectively considered as a valuable instrument for the prediction of component content in both raw and vinegar-processed Qingpi products. This study will provide new ideas and methods for identification and quality evaluation of Qingpi processed products, as well as provide a reference for standardizing traditional Chinese medicine processing techniques.

Mechanism insights into the pleiotropic effects of nobiletin as a potential therapeutic agent on non-alcoholic fatty liver disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases and is emerging as one of the fastest-growing causes of liver-related deaths worldwide. It is necessary to find strategies to effectively prevent and treat NAFLD, as no definitive drug has been approved. Nobiletin (NOB) is the critical active ingredient of Chinese herbal medicines such as Citrus aurantium and Citri Reticulatae Pericarpium, which have anti-inflammatory, antioxidant, lipid regulating, and insulin resistance regulating effects. Numerous studies have demonstrated that NOB can prevent and treat the onset and progression of NAFLD. In this review, the mechanisms of NOB for treating NAFLD have been summarized, hoping to provide a basis for subsequent studies of NOB and to provide a research ground for the development of therapeutic drugs for NAFLD.

The Self-Assembly Soluplus Nanomicelles of Nobiletin in Aqueous Medium Based on Solid Dispersion and Their Increased Hepatoprotective Effect on APAP-Induced Acute Liver Injury

Purpose

APAP-induced liver injury (AILI) is a common cause of acute liver failure (ALF). Nobiletin (NOB) is a potential hepatoprotective agent for the treatment of APAP-induced liver injury. However, the poor solubility and low bioavailability of NOB hinders its application. In this study, a novel self-assembly nano-drug delivery system of nobiletin (solid dispersion of NOB, termed as NOB/SD) was developed based on solid dispersion technology to improve the bioavailability and hepatoprotective ability of NOB for APAP-induced liver injury therapy.

Methods

The optimized NOB/SD system was constructed using the amphiphilic copolymers of Soluplus and PVP/VA 64 via hot melt extrusion technology (HME). NOB/SD was characterized by solubility, physical interaction, drug release behavior, and stability. The bioavailability and hepatoprotective effects of NOB/SD were evaluated in vitro and in vivo.

Results

NOB/SD maintained NOB in matrix carriers in a stable amorphous state, and self-assembled NOB-loaded nanomicelles in water. Nanostructures based on solid dispersion technology exhibited enhanced solubility, improved release behavior, and promoted cellular uptake and anti-apoptosis in vitro. NOB/SD displayed significantly improved bioavailability in healthy Sprague Dawley (SD) rats in vivo. Furthermore, NOB/SD alleviated the APAP-induced liver injury by improving anti-oxidative stress with reactive oxygen species (ROS) scavenging and nuclear factor erythroid 2-related factor 2 (Nrf2) activation.

Conclusion

These results suggested that NOB/SD could be considered as a promising hepatoprotective nano-drug delivery system for attenuating APAP-induced acute liver injury with superior bioavailability and efficient hepatoprotection, which might provide an effective strategy for APAP-induced acute liver injury prevention and treatment.

Evaluation and Optimization of Quality Based on the Physicochemical Characteristics and Metabolites Changes of Qingpi during Storage

Qingpi, the dried immature pericarp of Citrus reticulata Blanco, is a commonly used medicinal food with some health-promoting benefits. In general, it is essential that Qingpi be stored for a period of time, but there are no reports about the number of storage years needed to obtain the best quality of Qingpi. Our aim was to determine the best storage time of Qingpi by studying the physicochemical properties and metabolite changes in product stored from 1 to 5 years. As a result, the color of Qingpi became darker during storage. Both the levels of three flavonoids (hesperidin, nobiletin, and tangeretin) and total flavonoids (TFs) and the antioxidant activity decreased during storage and the total phenolics (TPs) content fluctuated during storage. Cluster analysis was performed on the color parameters measured using a color difference meter, revealing that the color of Qingpi differed before and after 3 years of storage. A total of 9 special differential metabolites were identified that could be used to distinguish the storage years of Qingpi. This is the first study to report the quality changes of Qingpi during storage. The optimized results of the quality evaluation indicated that Qingpi should be stored for no more than 3 years.

Extraction of flavonoids from Citri Reticulatae Pericarpium Viride using a deep eutectic solvent

Flavonoids are the main active ingredient in Citri Reticulatae Pericarpium Viride (CRPV). In this study, a deep eutectic solvent (DES) was explored to extract the main flavonoids from CRPV, including narirutin (NAR) and hesperidin (HES). A total of 30 DESs were prepared, and DES-20 (proline : urea) was selected as the optimal solvent. According to the single factor and response surface methodology experiments, the optimal extraction conditions for the flavonoids included a molar ratio of 1 : 2, water content of 30%, extraction time of 28 min, extraction power of 240 W, and a liquid-to-solid ratio of 70 mL g⁻¹ and the optimal extraction yields of NAR and HES were 21 ± 2 mg g⁻¹ and 60 ± 2 mg g⁻¹, respectively. The recovery rate of NAR and HES with macroporous resin SP825 were 88 ± 3% and 86 ± 4%, respectively. Compared with traditional extraction methods, this novel method greatly improved extraction efficiency and saved time. Scanning electron microscopy results showed that this novel method could destroy the plant cell wall to enhance the extraction efficiency. Then, 21 flavonoids were identified through an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) technique and nine of them were discovered for the first time in CRPV extracts. Furthermore, a high-performance liquid chromatography (HPLC) method was simultaneously used to determine NAR and HES in CRPV extracts upon methodological validation. Finally, antioxidant and cytotoxic experiments in vitro showed that the flavonoids extracted from the CRPV exhibited certain antioxidant and cytotoxic activities. The above results indicated that the DES was a green solvent, which can effectively extract NAR and HES from CRPV.

Flavonoids are the main active ingredient in Citri Reticulatae Pericarpium Viride (CRPV).