Review of recent advances on health benefits, microbial transformations, and authenticity identification of Citri reticulatae Pericarpium bioactive compounds.

The extensive health-promoting effects of Citri Reticulatae Pericarpium (CRP) have attracted researchers' interest. The difference in storage time, varieties and origin of CRP are closely related to the content of bioactive compounds they contain. The consitituent transformation mediated by environmental microorganisms (bacteria and fungi) and the production of new bioactive components during the storage process may be the main reason for 'the older, the better' of CRP. In addition, the gap in price between different varieties can be as large as 8 times, while the difference due to age can even reach 20 times, making the 'marketing young-CRP as old-CRP and counterfeiting origin' flood the entire market, seriously harming consumers' interests. However, so far, the research on CRP is relatively decentralized. In particular, a summary of the microbial transformation and authenticity identification of CRP has not been reported. Therefore, this review systematically summarized the recent advances on the main bioactive compounds, the major biological activities, the microbial transformation process, the structure, and content changes of the active substances during the transformation process, and authenticity identification of CRP. Furthermore, challenges and perspectives concerning the future research on CRP were proposed.

Citri Reticulatae Pericarpium Limits TLR-4-Triggered Inflammatory Response in Raw264.7 Macrophages by Activating RasGRP3.

Inflammation is an important immune response to pathogen invasion, but excessive inflammation leads to tissue injury and even cytokine storm. Therefore, proper response is needed depending on the intensity of the infection. Ras guanine nucleotide releasing protein 3 (RasGRP3) is a regulator of the TLR-mediated response. In low-intensity inflammation, it negatively regulates production of pro-inflammatory cytokines, especially IL-6. Citri Reticulatae Pericarpium, the peel of Citrus reticulata Blanco, is a major medicinal herb in Korean medicine. The present study aims to investigate whether the Citri Reticulatae Pericarpium extract (CRE) has immunomodulatory activity using the Raw264.7 macrophage. Also, we investigated the effect of CRE on RasGRP3 expression. In the present study, CRE reduced IL-6 production in the low-LPS environment (1 ng/mL) and did not in the high-LPS environment (100 ng/mL). The suppression of IL-6 production in the low-LPS environment (1 ng/mL) was abolished after the pretreatment of RasGRP3 siRNA. The reduced RasGRP3 protein content by 100 ng/mL LPS treatment was increased by CRE treatment. Additionally, nobiletin, a major component of CRE showed a suppressive effect on IL-6 production in the low-LPS environment (1 ng/mL). The present results suggest that CRE alleviates inflammatory response via activating RasGRP3 expression in low-intensity inflammation.

Citri Reticulatae Pericarpium alleviates postmyocardial infarction heart failure by upregulating PPARγ expression.

Heart failure after myocardial infarction (MI) is the leading cause of death worldwide. Citri Reticulatae Pericarpium (CRP) is a traditional Chinese herbal medicine that has been used in the clinic for centuries. In this study, we aimed to investigate the roles of CRP in cardiac remodelling and heart failure after MI, as well as the molecular mechanisms involved. Male C57BL/6 mice aged 8 weeks were subjected to coronary artery ligation to mimic the clinical situation in vivo. Echocardiography was used to assess the systolic function of the mouse heart. Masson trichrome staining and Wheat germ agglutinin (WGA) staining were utilised to determine the fibrotic area and cross-sectional area of the mouse heart, respectively. Cardiomyocytes and fibroblasts were isolated from neonatal rats aged 0-3 days in vitro using enzyme digestion. TUNEL staining and EdU staining were performed to evaluate apoptosis and proliferation, respectively. Gene expression changes were analysed by qRT-PCR, and protein expression changes were assessed by Western blotting. Our findings revealed that CRP attenuated cardiac hypertrophy, fibrosis and apoptosis and alleviated heart failure after MI in vivo. Furthermore, CRP mitigated cardiomyocyte apoptosis and fibroblast proliferation and differentiation into myofibroblasts. In addition, the PPARγ inhibitor T0070907 completely abolished the abovementioned beneficial effects of CRP, and the PPARγ activator rosiglitazone failed to further ameliorate cardiac apoptosis and fibrosis in vitro. CRP alleviates cardiac hypertrophy, fibrosis, and apoptosis and can ameliorate heart failure after MI via activation of PPARγ.

Comparison of Geqingpi and Sihuaqingpi based on ultra-high-performance liquid chromatography-tandem mass spectrometry combined with multivariate statistics, network pharmacology analysis, and molecular docking.

Citri Reticulatae Pericarpium Viride is used in traditional Chinese medicine as Geqingpi and Sihuaqingpi varieties. We used the ultra-high-performance liquid chromatography-quadrupole-Exactive Orbitrap-mass spectrometry method and high-performance liquid chromatography-triple quadrupole-tandem mass spectrometry to analyze the chemical compounds in these varieties. Principal components analysis and orthogonal partial least squares discriminant analysis were used to analyze the quantitative results. Network pharmacology and molecular docking technology were used to forecast Citri Reticulatae Pericarpium Viride treatment mechanisms in irritable bowel syndrome. We identified 44 main compounds in Citri Reticulatae Pericarpium Viride. Compared to Sihuaqingpi, Geqingpi had higher narirutin, didymin, naringenin, and hesperetin, and lower hesperidin, isosinensetin, nobiletin, 3,5,6,7,8,3',4'-hexamethoxyflavone, tangeretin. Tangeretin, nobiletin, narirutin, didymin, and isosinensetin were the main compounds distinguishing Geqingpi from Sihuaqingpi. We found that the MAPK signaling pathway, which is closely related to irritable bowel syndrome, was an important target pathway. TP53, HRAS, MAPK1, AKT1, and EGFR were important targets in this pathway. Eriodictyol-7-O-rutinoside, narirutin, limonin, and hesperidin showed a good binding ability to the five targets. Orientin, unique to Sihuaqingpi, bound well to TP53, MAPK1, AKT1, and EGFR, while rhoifolin bound well to TP53, HRAS, MAPK1, AKT1, and EGFR. Hesperetin, unique to Geqingpi, bound well to TP53, HRAS, and MAPK1, while naringenin bound well to HRAS. Hesperidin and didymin bound well to TP53, MAPK1, AKT1, and EGFR.

Mechanism of Citri Reticulatae Pericarpium as an Anticancer Agent from the Perspective of Flavonoids: A Review.

Citri Reticulatae Pericarpium (CRP), also known as "chenpi", is the most common qi-regulating drug in traditional Chinese medicine. It is often used to treat cough and indigestion, but in recent years, it has been found to have multi-faceted anti-cancer effects. This article reviews the pharmacology of CRP and the mechanism of the action of flavonoids, the key components of CRP, against cancers including breast cancer, lung cancer, prostate cancer, hepatic carcinoma, gastric cancer, colorectal cancer, esophageal cancer, cervical cancer, bladder cancer and other cancers with a high diagnosis rate. Finally, the specific roles of CRP in important phenotypes such as cell proliferation, apoptosis, autophagy and migration-invasion in cancer were analyzed, and the possible prospects and deficiencies of CRP as an anticancer agent were evaluated.

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

Citri Reticulatae Pericarpium Viride (CRPV) is the processed product of Citrus reticulata Blanco. We systematically analyzed two CRPV types, Geqingpi (GQP) and Sihuaqingpi (SHQP), based on powder color, microscopic characteristics, and chemical composition. In addition, we characterized their constituents via ultra-high-performance liquid chromatography with hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS). Both showed significant differences in their powder color and microscopic characteristics. Fourier-transform infrared (FT-IR) spectroscopic analysis results showed that the C=O peak absorption of carboxylic acids and their carbonyl esters in SHQP was higher than that of GQP, while the C-OH and C-H plane bending peaks of polysaccharides were lower than those of GQP. We analyzed these data via similarity analysis, PCA, and OPLS-DA. GQP and SHQP had large distinct differences. Based on the mass measurements for molecular and characteristic fragment ions, we identified 44 main constituents from CRPV, including different flavonoid glycosides and flavonoid aglycones in SHQP and GQP, respectively. We found luteolin-6-C-glucoside, orientin, rhoifolin, and pilloin solely in SHQP, and naringenin and hesperetin only in GQP. The peak area measurements showed GQP having a higher flavonoid glycoside (narirutin, hesperidin, etc.) content, whereas SHQP had a higher polymethoxyflavone (nobiletin, tangeretin, etc.) content. Since we holistically analyzed two CRPV types, the results can not only support future pharmacological research, but also provide a scientific basis for formulating more reasonable CRPV quality standards and guide its clinical potential as a precision medicine.

Bioinformatics-Guided Identification of Ethyl Acetate Extract of Citri Reticulatae Pericarpium as a Functional Food Ingredient with Anti-Inflammatory Potential.

Citri Reticulatae Pericarpium (CRP) is one of the most commonly used food supplements and folk medicines worldwide, and possesses cardiovascular, digestive, and respiratory protective effects partially through its antioxidant and anti-inflammatory functions. The unique aromatic flavor and mild side effects make CRP a promising candidate for the development of anti-inflammatory functional food. However, recent studies show that the crude alcoholic extract and some isolated compounds of CRP show compromised anti-inflammatory activity, which became the main factor hindering its further development. To identify the bioactive compounds with anti-inflammatory potential, and improve the anti-inflammatory effects of the extract, a bioinformatics-guided extraction protocol was employed in this study. The potential bioactive candidates were identified by combing network pharmacology analysis, molecular docking, principal components analysis, k-means clustering, and in vitro testing of reference compounds. Our results demonstrated that 66 compounds in CRP could be grouped into four clusters according to their docking score profile against 24 receptors, while the cluster containing flavonoids and phenols might possess a more promising anti-inflammatory function. In addition, in vitro anti-inflammatory tests of the seven reference compounds demonstrated that hesperitin, naringenin, and gardenin B, which were grouped into a cluster containing flavonoids and phenols, significantly decreased LPS-induced NO, TNF-α, and IL-6 production of macrophages. While the compounds outside of that cluster, such as neohesperidin, naringin, hesperidin, and sinensetin showed little effect on alleviating LPS-induced NO and proinflammatory cytokine production. Based on the chemical properties of selected compounds, ethyl acetate (EtOAc) was selected as the solvent for extraction, because of its promising solubility of flavonoids and phenols. Furthermore, the ethanol alcoholic extract was used as a reference. The chemical profiling of EtOAc and crude alcoholic extract by HPLC/MS/MS also demonstrated the decreased abundance of flavonoid glycosides in EtOAc extract but increased abundance of phenols, phenolic acid, and aglycones. In accordance with the prediction, the EtOAc extract of CRP, but not the crude alcoholic extract, significantly decreased the NO, IL-6, and TNF-α production. Taken together, the results suggested selective extraction of phenols and flavonoids rich extract was able to increase the anti-inflammatory potential of CRP partially because of the synergistic effects between flavonoids, phenols, and enriched polymethoxyflavones. Our study might pave the road for the development of ethyl acetate extract of CRP as a novel functional food with anti-inflammatory function.

[Research advances of chemical constituents and analytical methods of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium].

Citri Reticulatae Pericarpium Viride(CRPV) and Citri Reticulatae Pericarpium(CRP) are two commonly used Chinese medicinal materials. They have the same origin while are harvested in different seasons and have different clinical effects. They contain similar chemical components, like flavonoids, terpenes, volatile oils, and alkaloids. Although it has been demonstrated that differential components exist between them, there is still a lack of systematic comparison. Many studies have reported the chemical composition and quality evaluation of CRPV and CRP, including the characterization of flavonoids, alkaloids, and volatile oils via thin-layer chromatography, high-performance liquid chromatography, gas chromatography, infrared spectroscopy, and ultraviolet spectroscopy. A few studies have explored the differences between CRPV and CRP. In this paper, we systematically summarized the reported chemical composition, analytical methods, and quality evaluation of CRPV and CRP in recent ten years, aiming to facilitate the research on the pharmacodynamic material basis, quality evaluation, and standard improvement of CRPV and CRP.

[Contributions of flavonoids from citri reticulatae pericarpium to gastric hormones, CD3~+ and TFF3 mRNA expression in rats with spleen deficiency intervened by Liujunzi Decoction].

The present study established the spectrum-effect relationship model of flavonoids in Citri Reticulatae Pericarpium(CRP) from 15 batches of Liujunzi Decoction and statistically analyzed the correlation between chemical peaks and efficacy to identify the main effective components. HPLC fingerprints of flavonoids in CRP from 15 batches of Liujunzi Decoction were established. HPLC analysis was carried out on the Venusil XBP C_(18)(L) column(4.6 mm×250 mm, 5 µm) at 30 ℃ with acetonitrile-water(containing 0.1% formic acid) as mobile phase for gradient elution, a flow rate of 1.0 mL·min~(-1), and detection wavelength of 300 nm to obtain chemical fingerprints. Additionally, the effects of flavonoids from CRP in 15 batches of Liujunzi Decoction on the content of GAS, MTL, and VIP, TFF3 mRNA expression, and percentage of CD3~+ T-cells of model rats with spleen deficiency were determined. The spectrum-effect relationship model was established by gray correlation analysis. The results showed that the main characteristic peaks with great contribution to the regulation of gastrointestinal tract were peak 16(vicenin-2), peak 63(sinensetin), peak 64(isosinensetin), peak 65(nobiletin), peak 67(3,5,6,7,8,3',4'-heptemthoxyflavone), peak 68(tangeretin), and peak 69(5-desmethylnobiletin). Therefore, there was a linear correlation between flavonoids from CRP in Liujunzi Decoction and the efficacy, and the medicinal effect was achieved by multi-component action. This study is expected to provide a new idea for exploring the material basis of the effect, i.e., regulating qi prior to replenishing qi, of CRP in Liujunzi Decoction.

[Spleen deficiency and phlegm dampness syndrome model in rats treated by Citri Reticulatae Pericarpium based on metabolomics].

The present study analyzed the effect of Citri Reticulatae Pericarpium on endogenous metabolites in spleen deficiency and phlegm dampness syndrome by metabolomics, and explored the underlying mechanism of Citri Reticulatae Pericarpium in the treatment of spleen deficiency and phlegm dampness syndrome.The model of spleen deficiency and phlegm dampness syndrome was induced in rats by the multi-factor modeling method.The intervention effects of Citri Reticulatae Pericarpium on rats with spleen deficiency and phlegm dampness syndrome were preliminarily evaluated by observing the pathological changes of rat liver tissues and measuring the plasma content of pathological and biochemical indexes such as triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), and high-density lipoprotein cholesterol(HDL-C).Immunohistochemistry was used to detect the expression of AQP2 in the kidney, AQP3 in the colon, and AQP5 in the submandibular gland, and the effect of Citri Reticulatae Pericarpium on aquaporin expression in rats with spleen deficiency and phlegm dampness syndrome was evaluated.Furthermore, UHPLC-ESI-MS/MS was used to analyze the metabolic profiles of rat plasma samples.Multiple methods, such as principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) were used for pattern recognition.Differential metabolites were screened out by t-test and variable importance in projection(VIP), followed by pathway analysis based on MetaboAnalyst 5.0.As revealed by experimental results, Citri Reticulatae Pericarpium could improve the pathological changes of liver tissues, increase the levels of HDL-C in the plasma, reduce the levels of TC, TG, and LDL-C, and enhance the expression of AQP2 in the kidney, AQP3 in the colon, and AQP5 in the submandibular gland of rats with spleen deficiency and phlegm dampness syndrome.In addition, 87 differential metabolites of spleen deficiency and phlegm dampness syndrome were screened out by UHPLC-ESI-MS/MS(the levels of 39 metabolites increased significantly and the levels of 48 metabolites decreased significantly), with the representatives of glycine, L-isoleucine, N-acetyl-L-tyrosine, xanthine, hypoxanthine, and trigonelline.The differential metabolites were mainly enriched in the pathways of steroid hormone biosynthesis, linoleic acid metabolism, and purine metabolism.This study distinguished and revealed the characteristic metabolic pattern of spleen deficiency and phlegm dampness syndrome by metabolomics.The preliminary construction of the OPLS-DA model provides an objective basis for the differentiation of spleen deficiency and phlegm dampness syndrome in traditional Chinese medi-cine(TCM), as well as ideas and methods for exploring the biological basis of TCM syndrome from the molecular level and the overall level.

Simultaneous quantitative analysis of ten bioactive flavonoids in Citri Reticulatae Pericarpium Viride (Qing Pi) by ultrahigh-performance liquid chromatography and high-resolution mass spectrometry combined with chemometric methods.

INTRODUCTION: Citri Reticulatae Pericarpium Viride (Qing Pi in Chinese) is a clinically effective Chinese herb, which contains biologically valuable flavonoids. Qing Pi is divided into two commodity specifications, Si Hua Qing Pi (SHQP) and Ge Qing Pi (GQP), based on the harvesting time. The flavonoid contents in Qing Pi from different origins and commodity specifications may vary significantly, which will affect their therapeutic functions. Thus, it is crucial to set up a reliable and comprehensive quality evaluation method for flavonoid analysis in Qing Pi. OBJECTIVES: We aimed to establish a rapid and sensitive ultrahigh-performance liquid chromatography method coupled with diode-array detection and high-resolution mass spectrometry (UPLC-DAD-HRMS) for identification and quantification of ten flavonoids in Qing Pi. Chemometric methods were further applied to distinguish Qing Pi of different origins and specifications. METHODOLOGY: An UPLC-DAD-HRMS method was developed for the simultaneous separation and quantification of ten flavonoids in 46 batches of Qing Pi samples from different sources in China. Chemometric approaches were applied to discriminate Qing Pi from different origins and commodity specifications. RESULTS: The chemometric procedures (i.e., hierarchical clustering analysis and principal component analysis) were employed to identify the differences of Qing Pi samples with different origins and commodity specifications. The results showed that the contents of ten flavonoids in Qing Pi samples of different origins were significantly different, and the same results were found out between SHQP and GQP. CONCLUSIONS: This study provides a chemical basis for quality control of Qing Pi.

Rapid Discrimination of Citrus reticulata 'Chachi' by Electrospray Ionization-Ion Mobility-High-Resolution Mass Spectrometry.

A common idea is that some dishonest businessmen often disguise Citrus reticulata Blanco varieties as Citrus reticulata 'Chachi', which places consumers at risk of economic losses. In this work, we combined high-resolution ion mobility (U-shaped mobility analyzer) with high-resolution mass spectrometry to rapidly distinguish Citrus reticulata 'Chachi' from other Citrus species. The samples were analyzed directly through simple extraction and the analytes were separated in one second. It only took about 1 min to perform a cycle of sample analysis and data acquisition. The results showed that polymethoxylated flavones and their isomers were separated easily by the ion mobility analyzer and preliminarily identified according to the accurate mass. Moreover, the collision cross-section values of all analytes, which could be used as auxiliary parameters to characterize and identify the compounds in the samples, were measured. Twenty-four samples were grouped as two clusters by multivariate analysis, which meant that Citrus reticulata 'Chachi' could be effectively differentiated. It was confirmed that the developed method had the potential to rapidly separate polymethoxylated flavones and distinguish between Citrus reticulata 'Chachi' and other Citrus reticulata Blanco varieties.

[Improvement effect and mechanism of ethanol extract from Citri Reticulatae Pericarpium on triglyceride in hyperlipidemia model rat].

The aim of this paper was to study the improvement effect of ethanol extract from Citri Reticulatae Pericarpium(CRP) on triglyceride of hyperlipidemia model rats, and to explore the possible mechanism. SD rats were randomly divided into normal group, model group, positive control group, and high, medium and low-dose CRP ethanol extract groups, with 10 rats in each group. During the experiment, except for the normal group that was fed with distilled water and ordinary feed, rats in the other groups were given different concentrations of alcohol and fed with high-sugar and fat diets. All rats were given free diets. While being modeled, each group was administered with 0.01 mL·g~(-1) by gavage once a day for six weeks. Blood samples were collected after two weeks, four weeks and six weeks of drug treatment. After the completion of the experiment, blood, liver and adipose tissue were collected. Triglyceride(TG), alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP) in serum, TG in liver tissue and TG in fecal were detected. Free fatty acid(FFA) and triglyceride-related hydrolase, such as adipose tiglyceride lipase(ATGL), lipoprotein lipase(LPL), hepatic lipase(HL), hormone-sensitive triglyceride lipase(HSL) were detected by ELISA. The mRNA expressions of peroxisome proliferators-activated receptors(PPARγ), sterol regulatory element binding protein 1 c(SREBP-1 c) and farnesoid X receptor(FXR) were determined by RT-PCR. Compared with the model group, each administration group could reduce TG levels in serum and liver to varying degrees, reduce serum ALT, AST, ALP activities, significantly reduce free fatty acid content in serum, significantly increase triglyceride metabolism-related enzymes, including fat ATGL, LPL and liver HL content, and significantly reduced the content of fat HSL. According to the study of transcriptional regulation genes relating to triglyceride metabolism, extract from CRP could significantly increase the mRNA expressions of PPARγ and FXR. In conclusion, ethanol extract from CRP could ob-viously reduce the TG level of hyperlipidemia model rats, and might reduce plasma TG content by increasing PPARγ-LPL/ATGL and FXR-HL triglyceride hydrolysis pathways.

[Prediction of Q-markers of Citri Reticulatae Pericarpium volatile oil and GC-MS based quantitative analysis].

This study was designed to predict the Q-markers of Citri Reticulatae Pericarpium volatile oil and conduct quantitative analysis by GC-MS. The common components of Citri Reticulatae Pericarpium volatile oil were detected by GC-MS. The network pharmacology approaches were utilized for constructing the component-target network and protein-protein interaction(PPI) network, followed by the GO and KEGG pathway enrichment analysis to clarify the pharmacological effects of common components. Molecular docking was conducted to observe the biological activities of common components, thus identifying the Q-markers of Citri Reticulatae Pericarpium volatile oil. The obtained Q-markers were subjected to quantitative analysis by GC-MS. The GC-MS analysis of 19 batches of Citri Reticulatae Pericarpium volatile oil revealed three common components, namely, D-limonene, γ-terpinene, and myrcene. The common components were analyzed based on network pharmacology, and the results showed that Citri Reticulatae Pericarpium volatile oil mainly acted on the core targets GABRA1, GABRA6, GABRA5, GABRA3, and GABRA2 through D-limonene and γ-terpinene, with five important pathways such as nicotine addiction and GABAergic synapse involved. The core targets were mainly distributed in olfactory region, cerebral cortex, cerebellum, basal ganglia, hippocampus, and amygdala to exert the pharmacological effects. As revealed by molecular docking, D-limonene and γ-terpinene exhibited good biological activities, so they were identified as the Q-markers of Citri Reticulatae Pericarpium volatile oil. The results of quantitative analysis showed that the volume fraction of D-limonene was within the range of 0.77-1.03 µL·mL~(-1), and that of γ-terpinene within the range of 0.04-0.13 µL·mL~(-1). The prediction of D-limonene and γ-terpinene as the Q-markers of Citri Reticulatae Pericarpium volatile oil has laid an experimental foundation for the establishment of the quality evaluation standard for Citri Reticulatae Pericarpium volatile oil.

A Rapid and Nondestructive Approach for the Classification of Different-Age Citri Reticulatae Pericarpium Using Portable Near Infrared Spectroscopy.

Citri Reticulatae Pericarpium (CRP), has been used in China for hundreds of years as a functional food and medicine. However, some short-age CRPs are disguised as long-age CRPs by unscrupulous businessmen in order to obtain higher profits. In this paper, a rapid and nondestructive method for the classification of different-age CRPs was established using portable near infrared spectroscopy (NIRS) in diffuse reflectance mode combination with appropriate chemometric methods. The spectra of outer skin and inner capsule of CRPs at different storage ages were obtained directly without destroying the samples. Principal component analysis (PCA) with single and combined spectral pretreatment methods was used for the classification of different-age CRPs. Furthermore, the data were pretreated with the PCA method, and Fisher linear discriminant analysis (FLD) with optimized pretreatment methods was discussed for improving the accuracy of classification. Data pretreatment methods can be used to eliminate the noise and background interference. The classification accuracy of inner capsule is better than that of outer skin data. Furthermore, the best results with 100% prediction accuracy can be obtained with FLD method, even without pretreatment.

[Chemome profiling of Citri Reticulatae Pericarpium using UHPLC-IT-TOF-MS].

Citri Reticulatae Pericarpium(CRP, Chinese name: Chenpi) is one of the most famous edible traditional Chinese medicines(TCMs). CRP was first recorded as top grade TCM in Shennong Bencao Jing attributing to the benefits such as regulating Qi, tonifying spleen, eliminating dampness and eliminating phlegm, and has been widely utilized for the treatments of abdominal fullness and distention, vomiting and diarrhea, as well as phlegm cough. CRP is also widely popular as spice in food industry. Because of the wide cultivation, a number of brands that exhibit extensive price range can be found in the market, resulting in a great challenge for grading. Herein, an attempt was made to in-depth chemome profiling for the sake of providing meaningful information of the universal quality control of CRP. A new core-shell column packed with adamantylethyl substituted silica gel particles was deployed for chromatographic separations and IT-TOF-MS that is advantageous at providing abundant high resolution molecular and fragment ions was employed for qualitative detection. A total of 62 components were observed and 61 ones were structurally annotated according to proposing mass fragmentation patterns, matching with reference compounds and relevant databases, and the chemical families included flavone, limonin, etc. In particular, ten compounds bearing 3-hydroxy-3-methylglutarate substitute were detected from CRP for the first time. Above all, the chemical profile of CRP was characterized and the findings are meaningful for the in-depth quality assessment and efficacy material clarification of CRP.

Characterisation and classification of Citri Reticulatae Pericarpium varieties based on UHPLC-Q-TOF-MS/MS combined with multivariate statistical analyses.

INTRODUCTION: Citri Reticulatae Pericarpium (CRP), comprising dried pericarps of Citrus reticulata Blanco and its cultivars, is popularly used for its great medicinal and dietary values. Generally, the pericarps from C. reticulate "Chachi" ("Guangchenpi" in Chinese, GCP) is considered to have superior qualities and merit premium price compared with CRP derived from other cultivars (collectively called "Chenpi" in Chinese, CP). Since its multiple origins and derived economic adulteration, it is significant to systematically compare the chemical profiles of different CRP varieties. OBJECTIVE: The main objective of this work was to identify the chemical profiles of CRP from different varieties and find out potential chemical markers for differentiating GCP and CP. METHODS: In the present study, a total of 42 CRP samples from 10 varieties (including GCP and CP) were analysed by ultra-high performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS) for chemical profiling. Obtained MS/MS data were further employed in multivariate statistical methods to screen the main compounds which contributed to the characterisation and classification of CRP. RESULTS: As a result, 73 compounds (mainly flavonoids) were identified or tentatively characterised in these CRP samples. Based on the obtained chemical profiles data, GCP and CP samples could be easily discriminated from each other by statistical analyses. Moreover, seven compounds were selected as having the most discriminating features which contributed to the classification of CRP. CONCLUSION: This work obtains a better understanding of the chemical profiles of different CRP varieties and provides a practical strategy for the authentication of GCP and CP.

Study on the Discrimination between Citri Reticulatae Pericarpium Varieties Based on HS-SPME-GC-MS Combined with Multivariate Statistical Analyses.

Citri reticulatae pericarpium (CRP), the dried pericarps of Citrus reticulata Blanco and its cultivars, has been widely used in drugs and foods in China for centuries. In this study, an accurate and feasible analytical method based on HS-SPME-GC-MS coupled with multivariate statistical analyses was developed to comprehensively compare volatile compounds of pericarps derived from Citrus reticulata "Chachi" ("Guangchenpi" in Chinese, GCP) and other cultivars of Citrus reticulata Blanco ("Chenpi" in Chinese, CP). Principal component analysis, hierarchical cluster analysis, and orthogonal partial least-squares-discrimination analysis were performed to extract meaningful attributes from volatile profiles based on GC-MS data. Results indicated that samples from GCP and CP could easily be differentiated, and seven potential chemical markers were screened for the quality control of CRP. This study illuminated the volatile profile in CRP, and provides a practical method for the authentication of CRP varieties.

[Metabolic and excretory process of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium in rats' urine and feces analyzed by RRLC-QqQ-MSn].

This present study was to investigate the metabolism and excretion of characteristic polyphenols such as flavonoids and coumarins in urine and feces of rats after intragastric administration of ethanol extracts of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium. The urine and feces of rats were collected after intragastric administration of 70% ethanol extracts of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium. Rapid resolution liquid chromatography coupled with quadrupole tandem mass spectrometry (RRLC-QqQ-MSn) was applied to compare the contents of polyphenols in ethanol extract, urine and feces. By comparing with reference substance, 30 polyphenols were identified from the ethanol extracts of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium, including flavone glycosides, flavones, flavonone glycosides, flavonones, flavonol glycosides, polymethoxyflavones, coumarins, and limonoids and so on. The detection of various types of compounds showed differences in contents between the intestinal metabolism and excretion in the feces after systemic circulatory metabolism and renal excretion. The results showed that the polymethoxyflavones and flavonones were primarily excreted through urine, and the flavonone glycosides and limonoids were primarily excreted through feces. However, coumarins were hardly detected in feces and urine, indicating that coumarins may be metabolized in the body.

[Study on influence of different storage environments and packaging materials on quality of Citri Reticulatae Pericarpium].

Traditional Chinese herbs are readily contaminated by mold that produced mycotoxins which are closly related to the herbs' external factors and external environments during the storage process. In this study, Citri Reticulatae Pericarpium was used as example, and the characteristics of traits, water content, active components (naringin, hesperidin, sinensetin, naringin, tangeretin) and the accumulation of aflatoxins (AFs) were selected as the evaluation indexes. Citri Reticulatae Pericarpium was stored under different environments and packaging materials for 12 months, and then the quality changes and mildew of Citri Reticulatae Pericarpium were examined. The results showed that the color of Citri Reticulatae Pericarpium was deepened after storage, but without mildew phenomenon. Besides, the sample storage in kraft paper and woven bags had varying degrees of moth phenomenon after 12 months storage, and the water content exceeded the limit of Chinese Pharmacopoeia. In addition, the contents of the five active constituents obviously decreased, especially for hesperidin, which did not meet the pharmacopoeia standard after storage. AFs were not detected in any of the tested samples. According to the results, we conclude that low temperature and humidity environment is more suitable for the storage of Citri Reticulatae Pericarpium, and that packaging materials should be further investigated. This study is of great significance for preventing the mold to contaminate the traditional Chinese medicine and ensuring the quality, effectiveness and safety of TCMs.