Anti-asthmatic activity of alkaloid compounds from Pericarpium Citri Reticulatae (Citrus reticulata 'Chachi')

Short-term steaming during processing impacts the quality of Citri Reticulatae 'Chachi' peel

Citrus peel is a commonly used food-medicine material in the production of fast-moving consumer goods (FMCGs). For instance, Ganpu tea is manufactured by combining the peel of Citri Reticulatae 'Chachi' (PCRC) with Pu-erh tea. The alleviated irritation of PCRC through years of aging makes Citri reticulatae Pericarpium a traditional Chinese medicine. Herein, we introduced short-term steaming into the processing of PCRC to favor the quick removal of its irritation while retaining its food-medicine properties. Sensory evaluation and volatile component analysis showed that 60-s steaming reduced irritation of freshly prepared PCRC. Biological evaluations indicated no effects of steaming on the neuroprotective activity of PCRC. The process increased the contents of several bioactive ingredients, including hesperidin, nobiletin, tangeretin, and synephrine. In addition, physical indications of accelerating PCRC aging were observed. Taken together, our findings suggest that short-term steaming may offer a promising new possibility for enhancing the quality of citrus peel.

Airways Relaxant and Antiasthmatic Activity of Aconitum heterophyllum Wall ex Royle. Roots: A Mechanistic Insight

Aconitum heterophyllum Wall ex Royle. (Ranunculaceae) is a traditional medicinal herb that has shown extensive pharmacological potential to treat cough, diarrhea, and infectious diseases but no scientific evidence is available to validate its antiasthmatic potential. In this study, we have investigated the tracheal relaxation and antiasthmatic activity of the selected bioactive fraction of A. heterophyllum. Chemical profiling of the most effective fraction obtained via bioassay-guided fractionation was done using LC-MS (Liquid chromatography-mass spectrometry, a technique utilized in the identification, separation, and quantification of known and unknown compounds). Molecular docking analysis of characterized constituents was performed to recognize the binding receptors, followed by an evaluation of the tracheal relaxation ability of active fraction. An acute oral toxicity study of the most effective fraction was done using OECD guidelines 423. Further, the therapeutic efficacy of the fraction was validated in asthma using a guinea pig model of ovalbumin (OVA) induced allergic asthma. The bio-guided activity revealed that hydro-methanolic extract of A. heterophyllum roots (F-1) was the most active fraction. LC-MS analysis of F-1 showed the presence of six major bioactive compounds in F-1. Molecular docking studies revealed strong binding affinities of identified constituents with histaminic receptor (H1) and muscarinic receptor (M3). The ex vivo study demonstrated smooth muscle relaxant activity of F-1 via dysregulating diverse signal transduction pathways viz. histaminic and muscarinic receptors antagonism (non-competitive), stimulation of β2-adrenergic receptor pathway, and soluble guanylyl cyclase activation. The findings of acute oral toxicity studies revealed that F-1 had no toxicity up to the dose of 2000 mg/Kg. The anti-asthmatic therapeutic efficacy of F-1 was further confirmed by the amelioration of respiratory hyperresponsiveness in asthmatic guinea pigs. This is the first evidence-based study showing the antiasthmatic therapeutic potential of the traditionally used herb A. heterophyllum through, computational and animal studies.

Rapid analysis of bioactive compounds from citrus samples by direct analysis in real-time mass spectrometry combined with chemometrics

Renowned for their nutritional benefits, citrus fruits are harvested at various stages in China for functional food production. This study introduces an innovative analytical method, DART-MS, enabling direct qualitative analysis of citrus samples without the need for preprocessing. Simultaneously, the combination of chemometrics can be applied to distinguish between three different citrus samples: Citri Reticulatae Pericarpium, Citri Reticulatae Pericarpium Viride, and Citri Reticulatae "Chachi". Notably, given the international regulatory concerns surrounding synephrine, a precise quantitative analysis method for synephrine was developed. The limit of detection (LOD) and the limit of quantification (LOQ) were 39 ng mL-1 and 156 ng mL-1, respectively. The recovery rates obtained varied from 98.46% to 100.71%. Furthermore, the intra-day and inter-day precision demonstrated robust consistency, with values spanning 5.0-6.1% and 5.03-6.08%, respectively, offering quicker results compared to those from HPLC-MS, promising a safer assessment of herbal and food products.

Evaluation of chemical components and quality in Xinhui Chenpi (Citrus reticulata 'Chachi') with two different storage times by GC-MS and UPLC

Xinhui Chenpi (XHCP) is a well-known type of Chenpi (CP) widely used as both a Chinese herb and a food ingredient. While previous studies have explored how the quality of CP changes over time, there has been limited research specifically on XHCP. This study aims to assess the chemical components and quality of XHCP based on total flavonoid content (TF), antioxidant activity (AA), and color value (CV) at two stages: freshly harvested (XHCP-0Y) and after 3 years of storage (XHCP-3Y). Thirty-eight common volatile compounds were identified, and the content of 17 compounds among them, nine nonvolatile compounds, which included one alkaloid (synephrine), three phenolic acids (PA, protocatechuic acid, vanillic acid, and ferulic acid), and five flavonoids (narirutin, hesperidin, sinensetin, nobiletin, and tangeretin), were firstly detected by the newly developed gas chromatograph-mass spectrometer (GC-MS) and ultra-performance liquid chromatography (UPLC) methods. Compared to XHCP-0Y, the content of 17 volatile compounds and synephrine decreased in XHCP-3Y to varying degrees, while the content of PA, five flavonoids, TF, AA, and CV increased. The reduction of dryness caused by volatile compounds and the enhancement of efficacy related to PA, flavonoids, and AA suggested improved quality of XHCP after 3 years of storage. The methods developed in this study show promise for evaluating the quality of XHCP during the aging process.

Cinchonine: A Versatile Pharmacological Agent Derived from Natural Cinchona Alkaloids

BACKGROUND

Cinchonine is one of the Cinchona alkaloids that is commercially extracted from the Peruvian bark of Cinchona officinalis L. (Family: Rubiaceae). It is also obtained in much lower quantities from other species of Cinchona, such as Cinchona calisaya, Cinchona succirubra, and Cinchona pubescens, and in some other plants, such as Remijia peruviana. Cinchonine has been historically used as an anti-malarial agent. It also has a wide range of other biological properties, including anti-cancer, anti-obesity, anti-inflammatory, anti-parasitic, antimicrobial, anti-platelet aggregation, and anti-osteoclast differentiation.

AIM AND OBJECTIVE

This review discusses the pharmacological activity of cinchonine under different experimental conditions, including in silico, in vitro, and in vivo. It also covers the compound's physicochemical properties, toxicological aspects, and pharmacokinetics.

METHODOLOGY

A comprehensive literature search was conducted on multiple online databases, such as PubMed, Scopus, and Google Scholar. The aim was to retrieve a wide range of review/research papers and bibliographic sources. The process involved applying exclusion and inclusion criteria to ensure the selection of relevant and high-quality papers.

RESULTS

Cinchonine has numerous pharmacological properties, making it a promising compound for various therapeutic applications. It induces anti-cancer activity by activating caspase-3 and PARP-1, and triggers the endoplasmic reticulum stress response. It up-regulates GRP78 and promotes the phosphorylation of PERK and ETIF-2α. Cinchonine also inhibits osteoclastogenesis, inhibiting TAK1 activation and suppressing NFATc1 expression by regulating AP-1 and NF-κB. Its potential anti-inflammatory effects reduce the impact of high-fat diets, making it suitable for targeting obesity-related diseases. However, research on cinchonine is limited, and further studies are needed to fully understand its therapeutic potential. Further investigation is needed to ensure its safety and efficacy in clinical applications.

CONCLUSION

Overall, this review article explains the pharmacological activity of cinchonine, its synthesis, and physicochemical properties, toxicological aspects, and pharmacokinetics.

Mass Spectrometry Rearrangement Ions and Metabolic Pathway-Based Discovery of Indole Derivatives during the Aging Process in Citrus reticulata 'Chachi'

The rapid analysis and characterization of compounds using mass spectrometry (MS) may overlook trace compounds. Although targeted analysis methods can significantly improve detection sensitivity, it is hard to discover novel scaffold compounds in the trace. This study developed a strategy for discovering trace compounds in the aging process of traditional Chinese medicine based on MS fragmentation and known metabolic pathways. Specifically, we found that the characteristic component of C. reticulata 'Chachi', methyl N-methyl anthranilate (MMA), fragmented in electrospray ionization coupled with collision-induced dissociation (CID) to produce the rearrangement ion 3-hydroxyindole, which was proven to exist in trace amounts in C. reticulata 'Chachi' based on comparison with the reference substance using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Combining the known metabolic pathways of 3-hydroxyindole and the possible methylation reactions that may occur during aging, a total of 10 possible indole derivatives were untargeted predicted. These compounds were confirmed to originate from MMA using purchased or synthesized reference substances, all of which were detected in C. reticulata 'Chachi' through LC-MS/MS, achieving trace compound analysis from untargeted to targeted. These results may contribute to explaining the aging mechanism of C. reticulata 'Chachi', and the strategy of using the CID-induced special rearrangement ion-binding metabolic pathway has potential application value for discovering trace compounds.

Tylophora indica (Burm. f.) Merr alleviates tracheal smooth muscle hyperresponsiveness in ovalbumin-induced allergic-asthma model in guinea-pigs: Evidences from ex vivo, in silico and in vivo studies

BACKGROUND

Tylophora indica (Burm. f.) Merr is a climbing perennial plant reported in Indian traditional system of medicine for its use in allergy and asthma. However, only few scientific studies have been performed in the past to validate its antiasthmatic potential.

OBJECTIVES

The present study deals with investigation of airway smooth muscle relaxant and antiasthmatic potential of extract and subsequent fractions prepared from T. indica.

METHODS

The most active fraction of T. indica leaves selected through bio-guided activity was subjected to liquid chromatography-mass spectrometry (LC-MS) analysis for chemical profiling. The binding affinity of identified compounds in fraction towards M3 and H1 receptors was determined by molecular docking study. F-2 (chloroform fraction prepared from methanolic extract of T. indica leaves) was examined for its smooth muscle relaxant properties using isolated trachea of guinea-pig. Further, F-2 was evaluated through in vivo studies employing ovalbumin-induced asthma model in guinea-pigs.

RESULTS

F-2 was found most effective in bioassay-guided fractionation. Characterization by LC-MS analysis revealed presence of five major bioactive compounds in F-2 that showed good docking interactions with M3 and H1 receptors. The ex vivo study demonstrated that F-2 could significantly relax tracheal rings via targeting multiple signalling pathways videlicet, namely, noncompetitive antagonism of the histamine and muscarinic receptors, β2-adrenergic stimulation and activation of soluble guanylyl cyclase. In in vivo studies, F-2 ameliorated airway hyperresponsiveness and decreased broncho alveolar lavage fluid (BALF) levels of inflammatory cytokines and immunoglobulin E (IgE).

CONCLUSION

These results confirm the traditional use of T. indica as an antiasthmatic agent which are evidenced through ex vivo, in silico and in vivo studies.

Integrated metabolomics and network pharmacology to reveal antioxidant mechanisms and potential pharmacological ingredients of citrus herbs

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.

Effectiveness of kumquat decoction for the improvement of cough caused by SARS-CoV-2 Omicron variants, a multicentre, prospective observational study

BACKGROUND

Kumquat decoction is a traditional Chinese medicine formula and has been widely used to alleviate the coronavirus disease 2019 (COVID-19)-related cough in China. However, the effectiveness and safety of kumquat decoction remain unclear.

PURPOSE

To assess the effectiveness and safety of kumquat decoction for COVID-19-related cough.

STUDY DESIGN

A multicentre, prospective observational study.

METHODS

We enrolled consecutive patients with mild-to-moderate COVID-19 from December 31, 2022, to January 3, 2023, during the Omicron phase in Yangshuo County, China. The primary outcome was the time from study baseline to sustained cough resolution by the last follow-up day on January 31, 2023. The effectiveness was evaluated by Cox proportional hazards models based on propensity score analyses. The secondary outcomes were the resolution of cough and other COVID-19-related symptoms by Days 3, 5, and 7.

RESULTS

Of 1434 patients, 671 patients were excluded from the analysis of cough resolution. Among the remaining 763 patients, 481 (63.04%) received kumquat decoction, and 282 (36.96%) received usual care. The median age was 38.0 (interquartile range [IQR] 29.0, 50.0) years, and 55.7% were women. During a median follow-up of 7.000 days, 68.2% of patients in the kumquat group achieved sustained cough resolution (93.77 per 1000 person-days) compared to 39.7% in the usual care group (72.94 per 1000 person-days). The differences in restricted mean survival time (RMST) (kumquat decoction minus usual care group) for cough resolution were -0.742 days (95% CI, -1.235 to -0.250, P = 0.003) on Day 7. In the main analysis using propensity-score matching, the adjusted hazard ratio (HR) for cough resolution (kumquat decoction vs. usual care group) was 1.94 (95% CI, 1.48 to 2.53, P < 0.001). Similar findings were found in multiple sensitivity analyses. In addition, the use of kumquat decoction was associated with the resolution of cough, and a stuffy nose on Days 5 and 7, as well as the resolution of sore throat on Day 7 following medication.

CONCLUSION

In this study among patients with COVID-19-related cough, receiving kumquat decoction was associated with an earlier resolution of cough symptoms.

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.

Role of bZIP transcription factors in the regulation of plant secondary metabolism

MAIN CONCLUSION

This study provides an overview of the structure, classification, regulatory mechanisms, and biological functions of the basic (region) leucine zipper transcription factors and their molecular mechanisms in flavonoid, terpenoid, alkaloid, phenolic acid, and lignin biosynthesis. Basic (region) leucine zippers (bZIPs) are evolutionarily conserved transcription factors (TFs) in eukaryotic organisms. The bZIP TFs are widely distributed in plants and play important roles in plant growth and development, photomorphogenesis, signal transduction, resistance to pathogenic microbes, biotic and abiotic stress, and secondary metabolism. Moreover, the expression of bZIP TFs not only promotes or inhibits the accumulation of secondary metabolites in medicinal plants, but also affects the stress response of plants to the external adverse environment. This paper describes the structure, classification, biological function, and regulatory mechanisms of bZIP TFs. In addition, the molecular mechanism of bZIP TFs regulating the biosynthesis of flavonoids, terpenoids, alkaloids, phenolic acids, and lignin are also elaborated. This review provides a summary for in-depth study of the molecular mechanism of bZIP TFs regulating the synthesis pathway of secondary metabolites and plant molecular breeding, which is of significance for the generation of beneficial secondary metabolites and the improvement of plant varieties.

Stachydrine, a Bioactive Equilibrist for Synephrine, Identified from Four Citrus Chinese Herbs

Four Chinese herbs from the Citrus genus, namely Aurantii Fructus Immaturus (Zhishi), Aurantii Fructus (Zhiqiao), Citri Reticulatae Pericarpium Viride (Qingpi) and Citri Reticulatae Pericarpium (Chenpi), are widely used for treating various cardiovascular and gastrointestinal diseases. Many ingredients have already been identified from these herbs, and their various bioactivities provide some interpretations for the pharmacological functions of these herbs. However, the complex functions of these herbs imply undisclosed cholinergic activity. To discover some ingredients with cholinergic activity and further clarify possible reasons for the complex pharmacological functions presented by these herbs, depending on the extended structure-activity relationships of cholinergic and anti-cholinergic agents, a simple method was established here for quickly discovering possible choline analogs using a specific TLC method, and then stachydrine and choline were first identified from these Citrus herb decoctions based on their NMR and HRMS data. After this, two TLC scanning (TLCS) methods were first established for the quantitative analyses of stachydrine and choline, and the contents of the two ingredients and synephrine in 39 samples were determined using the valid TLCS and HPLC methods, respectively. The results showed that the contents of stachydrine (3.04‱) were 2.4 times greater than those of synephrine (1.25‱) in Zhiqiao and about one-third to two-thirds of those of Zhishi, Qingpi and Chenpi. Simultaneously, the contents of stachydrine, choline and synephrine in these herbs present similar decreasing trends with the delay of harvest time; e.g., those of stachydrine decrease from 5.16‱ (Zhishi) to 3.04‱ (Zhike) and from 1.98‱ (Qingpi) to 1.68‱ (Chenpi). Differently, the contents of synephrine decrease the fastest, while those of stachydrine decrease the slowest. Based on these results, compared with the pharmacological activities and pharmacokinetics reported for stachydrine and synephrine, it is indicated that stachydrine can be considered as a bioactive equilibrist for synephrine, especially in the cardio-cerebrovascular protection from these citrus herbs. Additionally, the results confirmed that stachydrine plays an important role in the pharmacological functions of these citrus herbs, especially in dual-directionally regulating the uterus, and in various beneficial effects on the cardio-cerebrovascular system, kidneys and liver.

Discrimination of Pericarpium Citri Reticulatae in different years using Terahertz Time-Domain spectroscopy combined with convolutional neural network

Pericarpium Citri Reticulatae (PCR) in longer storage years possess higher medicinal values, but their differentiation is difficult due to similar morphological characteristics. Therefore, this study investigated the feasibility of using terahertz time-domain spectroscopy (THz-TDS) combined with a convolutional neural network (CNN) to identify PCR samples stored from 1 to 20 years. The absorption coefficient and refractive index spectra in the range of 0.2-1.5 THz were acquired. Partial least squares discriminant analysis, random forest, least squares support vector machines, and CNN were used to establish discriminant models, showing better performance of the CNN model than the others. In addition, the output data points of the CNN intermediate layer were visualized, illustrating gradual changes in these points from overlapping to clear separation. Overall, THz-TDS combined with CNN models could realize rapid identification of different year PCRs, thus providing an efficient alternative method for PCR quality inspection.

Citri Reticulatae Pericarpium (Chenpi) Protects against Endothelial Dysfunction and Vascular Inflammation in Diabetic Rats

Dried tangerine peel (Citri reticulatae Pericarpium, CRP; Chenpi in Chinese) possesses medicine and food homology with hypolipidemic, anti-inflammatory and antioxidant activities. This study aimed to explore the protective effect of CRP extract on endothelial function and inflammation in type 2 diabetic rats and the related mechanisms. Type 2 diabetes mellitus was induced by high-fat diet (HFD)/streptozotocin (STZ) in male Sprague Dawley rats, and CRP extract was orally administered at 400 mg/kg/day for 4 weeks. Rat and mouse aortas were treated with high glucose and CRP extract ex vivo. The data showed that the ethanolic extract of CRP normalized blood pressure and the plasma lipid profile as well as the plasma levels of liver enzymes in diabetic rats. Impaired endothelium-dependent relaxations in aortas, carotid arteries and renal arteries were improved. CRP extract suppressed vascular inflammatory markers and induced AMPK activation in aortas of diabetic rats. Exposure to high glucose impaired vasodilation in aortas of rats and mice, and this impairment was prevented by co-incubation with CRP extract. In conclusion, our findings suggest that CRP extract protects endothelial function by inhibiting the vascular inflammatory state on activation of AMPK in diabetic rats.

Identification of Crucial Polymethoxyflavones Tangeretin and 3,5,6,7,8,3′,4′-Heptamethoxyflavone and Evaluation of Their Contribution to Anticancer Effects of Pericarpium Citri Reticulatae ‘Chachi’ during Storage

Pericarpium Citri Reticulatae ‘Chachi’ (PCR-C), rich in polymethoxyflavones (PMFs), has potential anticancer bioactivity and its quality will be improved during storage. However, the main factors influencing the PCR-C quality during its storage remain unclear. In this study, multivariate analysis was performed to investigate free and bound PMFs of PCR-C during storage. The anticancer effects of purified PCR-C flavonoid extracts (PCR-CF) and the important PMFs were evaluated using A549 cells. The results showed that PCR-C samples exhibited remarkable differences in free PMFs during storage, which fell into three clusters: Cluster 1 included fresh (fresh peel) and PCR-C01 (year 1); Cluster 2 consisted of PCR-C03 (year 3) and PCR-C05 (year 5); and PCR-C10 (year 10) was Cluster 3. 3,5,6,7,8,3′,4′-heptamethoxyflavone, tangeretin, and isosinensetin were identified as the most important PMFs distinguishing the various types of PCR-C according to its storage periods. Moreover, PCR-CF inhibited A549 cell proliferation and induced cell cycle arrest at G2/M phase, cell apoptosis, and ROS accumulation, and all anticancer indices had an upward tendency during storage. Additionally, tangeretin and 3,5,6,7,8,3′,4′-heptamethoxyflavone exhibited anticancer effects on A549 cells, whereas isosinensetin displayed no anticancer effect, indicating that tangeretin and 3,5,6,7,8,3′,4′-heptamethoxyflavone jointly contributed to anticancer activity of PCR-C during storage. PCR-CF and the most important PMFs killed cancer cells (A549 cells) but had no cytotoxicity to normal lung fibroblast cells (MRC-5 cells). Overall, the high quality of long-term stored PCR-C might be due to the anticancer effects of tangeretin and 3,5,6,7,8,3′,4′-heptamethoxyflavone.

Intraspecific DNA Barcoding and Variation Analysis for Citri Reticulatae Pericarpium of Citrus reticulata "Chachi"

Citri Reticulatae Pericarpium, the desiccative mature peel of Citrus reticulata Blanco or its cultivated varieties, is a national geographical indicated product that has the concomitant function of both medicine and foodstuff. The primary source of Citri Reticulatae Pericarpium is Citrus reticulata “Chachi,” called “Guang chenpi,” while it differs in variety, propagation, grafting rootstock, and tree age, and the hereditary stability of its biological information between intraspecific plants is worthy of our attention. Homologous analysis result of 4 DNA barcodings in the ribosome or the chloroplast showed that the homology of them (ITS2, rbcl, matK, and psbA-trnH) of 22 samples was 100.00%, 99.97%, 99.99%, and 99.81%, respectively, which indicated that 4 DNA barcodes maintained a high degree of genetic stability in Citrus reticulata “Chachi.” Also, ITS2 was considered to identify Citrus reticulata “Chachi” from other varieties because it presented not only low variability within a certain taxon but also a high level of interspecies variability. Simultaneously, variant site detection of Citrus reticulata “Chachi” was analyzed by comparing with the reference Citrus reticulata genome, and 2652697 SNP sites and 533906 InDel sites were detected from whole-genome resequencing data of 22 samples, providing the data resources and theoretical foundation for the future study about the relevant molecular makers of “Guang chenpi.”

Metabolomic insights into the inhibition mechanism of methyl N-methylanthranilate: A novel quorum sensing inhibitor and antibiofilm agent against Pseudomonas aeruginosa

The quorum sensing (QS) inhibition effect of methyl N-methylanthranilate (MMA) from Pericarpium Citri Reticulatae Chachiensis against foodborne pathogen Pseudomonas aeruginosa was reported for the first time. MMA effectively attenuated QS related virulence factors production and biofilm formation, while suppressed expression of a dozen of QS related genes. Untargeted LC-MS metabolomics revealed 108 significantly altered metabolites after MMA treatment. They indicated that MMA addition reduced the efficiency of TCA cycle and antioxidant systems, disturbed amino acid and nucleotide metabolism, increased unsaturated fatty acid and decreased peptidoglycan components, which might ultimately attenuate P. aeruginosa pathogenicity and restrain biofilm formation. Physiological characterization confirmed the compromised membrane integrity and increased intracellular oxidative stress after MMA treatment. Furthermore, metabolomics data implied that MMA inhibition on QS might exert through disrupting QS autoinducer PQS biosynthesis, which was supported by molecular docking. Our data indicated that MMA could be used as a novel QS inhibitor and anti-biofilm agent to improve food safety. It also provided new insight in the possible underlying inhibition mechanism of MMA and the response of P. aeruginosa to MMA.

Previously published ethno-pharmacological reports reveal the potentiality of plants and plant-derived products used as traditional home remedies by Bangladeshi COVID-19 patients to combat SARS-CoV-2

Several plants have traditionally been used since antiquity to treat various gastroenteritis and respiratory symptoms similar to COVID-19 outcomes. The common symptoms of COVID-19 include fever or chills, cold, cough, flu, headache, diarrhoea, tiredness/fatigue, sore throat, loss of taste or smell, asthma, shortness of breath, or difficulty breathing, etc. This study aims to find out the plants and plant-derived products which are being used by the COVID-19 infected patients in Bangladesh and how those plants are being used for the management of COVID-19 symptoms. In this study, online and partially in-person survey interviews were carried out among Bangladeshi respondents. We selected Bangladeshi COVID-19 patients who were detected Coronavirus positive (+) by RT-PCR nucleic acid test and later recovered. Furthermore, identified plant species from the surveys were thoroughly investigated for safety and efficacy based on the previous ethnomedicinal usage reports. Based on the published data, they were also reviewed for their significant potentialities as antiviral, anti-inflammatory, and immunomodulatory agents. We explored comprehensive information about a total of 26 plant species, belonging to 23 genera and 17 different botanical families, used in COVID-19 treatment as home remedies by the respondents. Most of the plants and plant-derived products were collected directly from the local marketplace. According to our survey results, greatly top 5 cited plant species measured as per the highest RFC value are Camellia sinensis (1.0) > Allium sativum (0.984) > Azadirachta indica (0.966) > Zingiber officinale (0.966) > Syzygium aromaticum (0.943). Previously published ethnomedicinal usage reports, antiviral, anti-inflammatory, and immunomodulatory activity of the concerned plant species also support our results. Thus, the survey and review analysis simultaneously reveals that these reported plants and plant-derived products might be promising candidates for the treatment of COVID-19. Moreover, this study clarifies the reported plants for their safety during COVID-19 management and thereby supporting them to include in any future pre-clinical and clinical investigation for developing herbal COVID-19 therapeutics.

Flavonoid glycosides and other bioactive compounds in Citrus reticulate 'Chachi' peel analysed by tandem mass spectrometry and their changes during storage

The peel of Citrus reticulate 'Chachiennsis' (Chachi) is a well-known functional food with multiple health benefits in Asia. There is an old saying "the longer time Chachi is stored, the better health benefits it has". Is it convincible? What are the critical bioactive compounds in Chachi? To answer these questions, gas chromatography-mass spectrometry (GC-MS) and ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) were used to qualify and quantify the flavonoid glycosides and other bioactive compounds of Chachi with storage time of 5-20 years. Limonene was the representative volatile compound. The level of most volatile compounds decreased along with storage. Sixteen flavonoids glycosides and twenty flavonoids were identified. Nobiletin, hesperitin, tetramethoxy flavone and pentamethoxy flavone were characteristic bioactive compounds for Chachi. Most of them accumulated during 10-year storage, thereafter decreased. Ten years could be the optimal storage time. These results indicated that the old saying should be corrected.

Characterization of polysaccharide structure in Citrus reticulate 'Chachi' peel during storage and their bioactivity

The peel of Citrus reticulate 'Chachiennsis' (Chachi) is widely accepted as a functional food. It is generally recognized that its health benefits are dependent on storage time. However, the chemicals responsible for this phenomonon remain unclear. As bioactive polysaccharides are dominant in Chachi, Chachi polysaccharides with various storage times (5-20 years) were prepared. The monosaccharide composition was analyzed by GC-MS. NMR data revealed that Chachi polysaccharides were mainly consisted of arabinogalacturonan and another pectin with side chain of →4)-β-D-Galp-(1 → . α-L-Araf-(1→, →5)-α-L-Araf-(1→, →4)-α-D-GalpA-(1→, →4)-α-D-GalpAMe-(1→, →4)-β-D-Galp-(1→ and →4)-β-D-Glcp-(1→ were detected. The molecular weight of Chachi polysaccharides decreased along with the extension of storage time. However, the basic structure characteristics remained stable. The immumomodulatory activities of Chachi polysaccharides were improved as the storage time extended. The change of molecular weight was responsible for the improved immunomodulatory activity. The results explained how polysaccharides contributed to the enhanced health benefits of Chachi during storage.

Effects of Different Treatment Methods of Dried Citrus Peel (Chenpi) on Intestinal Microflora and Short-Chain Fatty Acids in Healthy Mice

Chenpi is a kind of dried citrus peel from Citrus reticulata, and it is often used as traditional Chinese medicine to treat dyspepsia and respiratory tract inflammation. In this study, to determine which way of chenpi treatment plays a better effect on the prevention of obesity in healthy mice, we conducted 16S ribosomal RNA (rRNA) gene sequencing for intestinal microbiota and gas chromatography-mass spectrometry detector (GC/MSD) analysis for short-chain fatty acids (SCFAs) of female rats fed with either chenpi decoction or chenpi powder-based diet (n = 10 per group) for 3 weeks. Chenpi powder (CP) group significantly reduced abdominal adipose tissues, subcutaneous adipose tissue, and the serum level of total triacylglycerol (TG). At a deeper level, chenpi powder has a better tendency to increase the ratio of Bacteroidetes to Firmicutes. It alters the Muribaculaceae and Muribaculum in intestinal microbiota, though it is not significant. The concentrations of acetic acid, valeric acid, and butyric acid increased slightly but not significantly in the CP group. Chenpi decoction just reduced perirenal adipose tissues, but it shows better antioxidant activity. It has little effect on intestinal microbiota. No differences were found for SCFAs in the chenpi decoction (CD) group. The results indicated that chenpi powder has a better effect in preventing obesity in mice. It can provide a basis for the development of functional products related to chenpi powder.

A review of chemical constituents and health-promoting effects of citrus peels

Citrus is one of the main fruits processed worldwide, producing a lot of industrial by-products. As the main part of citrus "residue", citrus peels have a wide application prospect. They could not only be directly used to produce various food products, but also be used as promising biofuels to produce ethanol and methane. Additionally, functional components (flavonoids, limonoids, alkaloids, essential oils and pectin) extracted from citrus peels have been related to the improvement of human health against active oxygen, inflammatory, cancer and metabolic disorders. Therefore, it is clear that the citrus peels have great potential to be developed into useful functional foods, medicines and biofuels. This review systematically summarizes the recent advances in current uses, processing, bioactive components and biological properties of citrus peels. A better understanding of citrus peels may provide reference for making full use of it.

Probiotic Potential and Cholesterol-Lowering Capabilities of Bacterial Strains Isolated from Pericarpium Citri Reticulatae 'Chachiensis'

Pericarpium Citri Reticulatae 'Chachiensis' (PCR-Chachiensis), the pericarps of Citri Reticulatae Blanco cv. Chachiensis, is a food condiment and traditional medicine in southeast and eastern Asia. Its rich and various bacterial community awaits exploration. The present study is the first report on probiotic screening and characterization of bacteria from PCR-Chachiensis. Based on 64 culturable bacterial isolates, 8 strains were screened out to have great survival in the simulated gastrointestinal stressful condition, being nonhemolytic and without biogenic amine formation. They were identified by 16S rRNA gene sequencing as two Bacillus, three Lactobacillus, and three strains from Bacillales. Their probiotic properties, cholesterol-lowering potential and carbohydrate utilization capability were further investigated. Though these eight strains all displayed distinct cholesterol removal potential, Bacillus licheniformis N17-02 showed both remarkable cholesterol removal capability and presence of bile salt hydrolase gene, as well as possessing most of the desirable probiotic attributes. Thus, it could be a good probiotic candidate with hypocholesterolemic potential. Bacillus megaterium N17-12 displayed the widest carbohydrate utilization profile and the strongest antimicrobial activity. Hence, it was promising to be used as a probiotic in a host and as a fermentation starter in fermented food or feed.

Evaluation of dynamic changes in the bioactive components in Citri Reticulatae Pericarpium (Citrus reticulata 'Chachi') under different harvesting and drying conditions

BACKGROUND

The Citrus reticulata 'Chachi' pericarp (CRCP) is one cultivar of Citri Reticulatae Pericarpium (Chenpi), which is widely applied in medicine and food. To determine the potential value of CRCP harvested at different stages and subjected to different drying processes, the dynamic changes in the bioactive components were profiled and evaluated in this study.

RESULTS

The contents of all non-volatile components, i.e. synephrine, limonin, phenolic acids and flavonoids, decreased with delayed harvest time. The volatiles thujene, α-pinene, β-pinene, d-citronellol, d-citronellal, decanal, linalool, geraniol, l-cis-carveol, terpinen-4-ol, α-terpineol, carvacrol, perillaldehyde, methyl 2-(methylamino)benzoate and d-limonene were considered the characteristic components for distinguishing CRCP harvested at different stages. Phenolic acids, synephrine and limonin were stable at different drying temperatures; however, high-temperature drying at 60 °C induced a significant transformation in the flavonoids (especially polymethoxyflavones) and volatile substances in CRCP.

CONCLUSIONS

The results suggested that most of the bioactive components declined with the growth of Citrus reticulata 'Chachi'. And it is believed that the fresh peel should be naturally sun-dried or dried at low temperature (30 or 45 °C) rather than at high temperature (60 °C) to prevent excessive loss of nutrients. © 2020 Society of Chemical Industry.

Extraction process and method validation for bioactive compounds from Citrus reticulata cv. Chachiensis: Application of response surface methodology and HPLC–DAD

Citrus reticulata cv. Chachiensis, a traditional Chinese herb, has extensive medicinal and edible effects. 3′,4′,5,6,7,8-Hexamethoxyflavone (HM) and 5,6,7,8,4′-pentamethoxyflavone (PM) are main bioactive compounds in Chachiensis, which have been reported to possess various biological properties. In this study, supercritical CO2 extraction (SCE) and high-speed countercurrent chromatography (HSCCC) were utilized to prepare HM and PM from Chachiensis. The contents of target compounds were determined by a high-performance liquid chromatography method with diode-array detection (HPLC-DAD), which was validated using the following parameters: linearity, sensitivity, repeatability, stability, precision and accuracy. The SCE conditions were optimized using response surface methodology with central composite design. Obtained optimum conditions were temperature of 37.9 °C, pressure of 26.3 MPa, and modifier volume of 81.0 mL. Under above conditions, the recoveries of target compounds were 92.52 ± 0.83 and 96.36 ± 0.43%, respectively. The most appropriate solvent system for HSCCC was selected as n-hexane/ethyl acetate/methanol/water (1:0.8:1:1.2, v/v). The HSCCC fractions were detected by HPLC-DAD, liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR). The results indicated that this method was successfully applied to obtain HM and PM with high purities and high recoveries from Chachiensis.

Herb pair of Ephedrae Herba-Armeniacae Semen Amarum alleviates airway injury in asthmatic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ephedrae Herba (EH, Ephedra sinica Stapf.) and Armeniacae Semen Amarum (ASA, Prunus armeniaca L. var. ansu Maxim.) have been used to treat asthma, cold, fever, and cough in China for thousands of years.

AIM OF THE STUDY

In this study, we aimed to investigate the optimal ratio of EH and ASA compatibility (EAC) to reduce airway injury in asthmatic rats and its possible mechanism.

METHODS

Rats were sensitized with a mixture of acetylcholine chloride and histamine bisphosphate 1 h before sensitization by intragastric administration of EAC or dexamethasone or saline for 7 days. Subsequently, the ultrastructure of rat airway epithelial tissue changes, apoptosis of the airway epithelial cells, and the expression of mRNA and protein of EGRF and Bcl-2 were detected.

RESULTS

Transmission electron microscope: EAC (groups C and E) had the most prominent effect on repairing airway epithelial cells' ultrastructural changes in asthmatic rats. TUNEL: dexamethasone and EAC (groups B、C、E and F) inhibited the apoptosis of airway epithelial cells in asthmatic rats (P < 0.05). In situ hybridization: EAC (group E) inhibited the overexpression of EGFR and Bcl-2 mRNA (P < 0.05).Western Blotting: EAC (groups A、B、C、E and F) inhibited the upregulation of airway epithelial EGFR and Bcl-2 protein expression (P < 0.01).

CONCLUSIONS

Our findings indicate that EAC can inhibit abnormal changes in airway epithelial structure and apoptosis of airway epithelial cells, thereby alleviating airway injury. In this study, the best combination of EH and ASA to alleviate airway epithelial injury in asthmatic rats was group E (EH: ASA = 8: 4.5).

Antiobesity effects of kimchi added with Jeju citrus concentrate on high-fat diet-induced obese mice

Citrus fruits contain an abundance of nutrients, including vitamins C and B₆ and hesperidin, which attribute to its beneficial health effects. Previously, kimchi with Jeju citrus concentrate (CK) elicited anti-obesity effects in 3T3-L1 adipocytes. Here, we aimed to investigate whether CK exhibits anti-obesity effects by reducing serum and hepatic lipid concentrations and anti-obesity-associated gene expression in high-fat diet (HFD)-induced obese C57BL/6N mice. Low-dose CK (LDCK, 50 mg/kg) and high-dose CK (HDCK, 200 mg/kg) were orally administered 3 times per week over 8 weeks with HFD diet. Body weight gain, food efficiency ratio, and tissue weight were measured. Serum glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance, leptin, and adiponectin concentrations were also assessed. The effect of CK on the lipid profile and lipid accumulation was analyzed. Body and white adipose tissue masses were significantly lower in the LDCK and HDCK groups than in the HFD group. Orally administered CK significantly decreased serum lipid, fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase levels. Hepatic lipid content also decreased in the LDCK and HDCK groups. Serum leptin concentrations decreased, whereas serum adiponectin concentrations increased, confirming the anti-obesity effects of LDCK and HDCK. The decrease of hepatic vacuoles and stained lipid droplets indicated inhibition of lipid accumulation. These results support the hypothesis that CK exhibits anti-obesity effects in vivo by reducing lipid accumulation and by regulating anti-obesity-related genes.

Systematic Review: Guideline-Based Approach for the Management of Asthma and Subtypes via Chinese Medicine

Background

Asthma is a chronic condition that results in the inflammation and narrowing of airways, often clinically presenting as wheeze and shortness of breath. Little is known of the mechanisms of action (MOA) of herbs used to treat asthma. The aim of this study is to review existing data regarding known MOA of traditional Chinese medicine which will aid in the understanding of possible interactions between Western drugs and Chinese herbs as well as the standardization of management via a proposed guideline to improve patient safety and possible synergism in the long term.

Methods

We searched through 5 databases for commonly prescribed herbs and formulas for asthma and narrowed down the search to identify the underlying MOA of individual herbs that could specifically target asthma symptoms. We included studies that stated the MOA of individual herbs when used for treating symptoms of asthma, excluding them if they are described as part of a formula.

Results

A total of 26 herbs commonly prescribed for asthma with known mechanism of action were identified. Herbs used for asthma were found to have similar MOA as that for drugs. Based on existing GINA guidelines, a guideline is proposed which includes a total of 5 steps depending on the severity of asthma and the herbs' MOA. 16 formulas were subsequently identified for the management of asthma, which consist of 12 “stand-alone” and 4 “add-on” formulas. “Stand-alone” formulas used independently for asthma generally follow the GINA guidelines but do not proceed beyond step 3. These formulas consist mainly of beta-agonist and steroid-like effects. “Add-on” formulas added as adjunct to “stand-alone” formulas, however, mainly act on T helper cells or have steroid-like effects.

Conclusion

Through the understanding of MOA of herbs and their respective formulas, it will ensue greater patient safety and outcomes.

Meta-Analysis on the Chinese Herbal Formula Xiaoer-Feike Granules as a Complementary Therapy for Children With Acute Lower Respiratory Infections

Background

Over the past five years the Chinese herbal formula (CHF) medicine, Xiaoer-Feike granules (XFG), has become a widely used adjuvant therapy for acute lower respiratory infections (ALRI). Considering the rapid popularization and application of XFG, and the lack of systematic evidence evaluating its effectiveness and safety in treating ALRI, it is necessary to conduct a meta-analysis to determine its benefits for patients.

Methods

This study systematically identified randomized controlled trials (RCTs) of XFG treatments for ALRI through July 2019 using four English-databases (PubMed, Cochrane Library, Ovid, and Web of Science) and four Chinese-databases (Sino-med database, China National Knowledge Infrastructure (CNKI), VIP database, and the WANFANG database). We then performed a quality assessment and data analysis with Review Manager 5.3.5 and Stata 15.1.

Results

Twenty-one RCTs involving 3425 patients were randomly divided into an XFG group and a conventional medicine (CM) group. The results showed that the clinical efficacy rate (CER) of the XFG group was significantly higher than that of the CM group (RR=1.17, 95% CI =1.13-1.22, P< 0.00001). In comparison with the CM group, the XFG group had strikingly shortened: resolution time of cough (RTC) (MD = -1.92; 95% CI =-2.33, -1.51, P<0.00001); resolution time of rale (RTR) (MD = -1.68; 95% CI =-2.27, -1.10, P<0.00001); resolution time of fever (RTF) (MD = -1.46; 95% CI =-1.92, -1.00, P<0.00001); resolution time of inflammatory lesions (RTIL) (MD = -2.43, 95% CI =-2.94, -1.93, P< 0.00001); and hospital stays (HS) (MD = -2.26, 95% CI =-3.03, -1.49, P< 0.00001). At the cellular and molecular level, the CD4, CD8, CD4/CD8, IL-6, TNF-α, and CRP levels were significantly improved when CM was complemented with XFG. In addition, no significant difference was observed between the XFG and CM groups in terms of the adverse events (AE) (RR =0.97, 95% CI= 0.61-1.54, P= 0.89).

Conclusions

The findings of this meta-analysis support the use of XFG in the treatment of ALRI. However, these results should be treated with caution due to the significant heterogeneity and publication bias of existing data. Further well-designed and high-quality RCTs are needed to interrogate the efficacy and safety of XFG.

Identification of lipophilic components in Citri Reticulatae Pericarpium cultivars by supercritical CO2 fluid extraction with ultra-high-performance liquid chromatography-Q Exactive Orbitrap tandem mass spectrometry

To systematically identify the lipophilic constituents of Citri Reticulatae Pericarpium from different cultivars, supercritical CO₂ fluid extraction and ultra-high-performance liquid chromatography-Q Exactive Orbitrap tandem mass spectrometry were integrated for the component analysis of 18 batches of Citri Reticulatae Pericarpium from 12 cultivars for the first time. A total of 57 components from the supercritical CO₂ fluid extracts were demonstrably or tentatively identified by the obtained parent peaks, fragment peaks, and retention times. In total, two flavonoids, six organic acids, nine coumarins, three aldehydes, seven esters, three terpenes, one limonoid, and five other compounds were detected for the first time; notably, coumarin components have not yet been reported in Citri Reticulatae Pericarpium. Furthermore, the extract constituents differed between cultivars. In particular, organic acids were more abundant in Citrus reticulata "Chachi" than in other cultivars, and pterostilbene was exclusively found in Citrus reticulata "Yichangju". The results showed that a greater variety of compounds in Citri Reticulatae Pericarpium could be extracted by supercritical CO₂ fluid extraction and detected by ultra-high-performance liquid chromatography-Q Exactive Orbitrap tandem mass spectrometry. This study provides a more scientific basis for further analysis of the pharmacological activity and quality of Citri Reticulatae Pericarpium components from different cultivars.

Plants derived therapeutic strategies targeting chronic respiratory diseases: Chemical and immunological perspective

The apparent predicament of the representative chemotherapy for managing respiratory distress calls for an obligatory deliberation for identifying the pharmaceuticals that effectively counter the contemporary intricacies associated with target disease. Multiple, complex regulatory pathways manifest chronic pulmonary disorders, which require chemotherapeutics that produce composite inhibitory effect. The cost effective natural product based molecules hold a high fervor to meet the prospects posed by current respiratory-distress therapy by sparing the tedious drug design and development archetypes, present a robust standing for the possible replacement of the fading practice of poly-pharmacology, and ensure the subversion of a potential disease relapse. This study summarizes the experimental evidences on natural products moieties and their components that illustrates therapeutic efficacy on respiratory disorders.

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Plant derived therapeutics for managing chronic respiratory disorders.

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Activity of natural product based molecules on key regulatory pathways of COPD.

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Preclinical evidence for the efficacy of natural product moieties.

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Clinical significance of plant derived molecules in pulmonary distress.

A review of pharmacological and pharmacokinetic properties of stachydrine

Stachydrine is extracted from the leaves of Leonurus japonicus Houtt (or Motherwort, "Yi Mu Cao" in Traditional Chinese Medicine) and is the major bioactive ingredient. So far, stachydrine has demonstrated various bioactivities for the treatment of fibrosis, cardiovascular diseases, cancers, uterine diseases, brain injuries, and inflammation. The pharmacological and pharmacokinetic properties of stachydrine up to 2019 have been comprehensively searched and summarized. This review provides an updated summary of recent studies on the pharmacological activities of stachydrine. Many studies have demonstrated that stachydrine has strong anti-fibrotic properties (on various types of fibrosis) by inhibiting ECM deposition and decreasing inflammatory and oxidative stress through multiple molecular mechanisms (including TGF-β, ERS-mediated apoptosis, MMPs/TIMPs, NF-κB, and JAK/STAT). The cardioprotective and vasoprotective activities of stachydrine are related to its inhibition of β-MHC, excessive autophagy, SIRT1, eNOS uncoupling and TF, promotion of SERCA, and angiogenesis. In addition to its anticancer action, regulation of the uterus, neuroprotective effects, etc. the pharmacokinetic properties of stachydrine are also discussed.