Comparison of Multiple Bioactive Constituents in the Corolla and Other Parts of Abelmoschus manihot

Qualitative and quantitative analysis of major components in Abelmoschus manihot flowers treated with different drying methods using UHPLC Q-exactive MS and HPLC-PDA

The flowers of Abelmoschus manihot (L.) Medic are commonly used in clinical practice in China to cure forms of chronic kidney disease. Despite a long history of traditional use, the flowers obtained by different drying technologies have never been fully chemically characterized, and the ranges of constituents between different drying methods have not been comprehensively reported. To establish a quality control and chemical characterization method, a total of 14 batches of samples corresponding to 14 postharvest treatments were studied. Seven flavonoids were quantified using a HPLC-PDA method. The method was validated in terms of linearity (r > 0.999), precision (intra- and inter-day: 0.7-1.4 %), accuracy (99.90-100.7 %), detection limit (0.34-0.46 µg/mL) and quantification limit (1.15-1.52 µg/mL). The contents of total flavonoids in manihot flowers were as follows in descending order: Infrared Drying (50.96 mg/g) > Microwave Drying (41.84 mg/g) ≈ Hot-air Drying (39.58 mg/g) ≈ Fresh (39.35 mg/g) ≈ Primary Drying (38.95 mg/g). Principal component analysis showed that samples processed with Fresh, Primary Drying, and the investigated three modern drying methods were well classified into three domains, indicating an important difference between drying methods. For the purpose of saving the flavonoids contents, infrared drying under 80-100 °C would be most acceptable. Furthermore, using UHPLC Q-Exactive Orbitrap MS data with targeted and non-targeted approaches, 28 compounds were identified in Abelmoschus manihot samples. Flavonoids were the main group of compounds found in Abelmoschus manihot flowers. The study could provide the scientific evidence for the selection and optimization of appropriate drying method for manihot flowers, and also provide the reference for the formation of generic primary drying processing technology for medicinal flowers containing flavonoids.

Application of Mass Spectrometry for Analysis of Nucleobases, Nucleosides and Nucleotides in Tea and Selected Herbs: A Critical Review of the Mass Spectrometric Data

The main and most commonly known biological function of nucleobases, nucleosides, and nucleotides is usually associated with the fact that they are the building blocks of nucleic acids. However, these compounds also belong to plant secondary metabolites, although in that role they have attracted less attention than the others, e.g., terpenes, phenolics, or alkaloids. The former compounds are also important constituents of the human diet, e.g., as ingredients of tea and herbs, endowing them with specific taste qualities and pharmacological activities. Liquid chromatography-mass spectrometry seems to be the most important analytical method that permits the identification and determination of nucleobases, nucleosides, and nucleotides, along with the other metabolites. The main goal of this review is to discuss in detail the aspects of mass spectrometric detection of nucleobases, nucleosides, and nucleotides in tea and selected herbs. An important conclusion is that the identification of the compounds of interest should be performed not only on the basis of [M + H]+/[M - H]- ions but should also be confirmed by the respective product ions; however, as discussed in detail in this review, it may sometimes be problematic. It also clear that all difficulties that may be encountered when analyzing plant material are caused by the complexity of the analyzed samples and the need to analyze different classes of compounds, and this review absolutely does not debase any of the mentioned papers.

Comparative study on chemical constituents of different medicinal parts of Lonicera japonica Thunb. Based on LC-MS combined with multivariate statistical analysis

Lonicerae japonicae flos (LJF), Lonicerae japonicae caulis (LJC), Lonicerae folium (LF) and Lonicerae fructus (LFR) are derived from Lonicera japonica Thunb., which are formed due to different medicinal parts. The efficacy of the 4 medicinal materials has similarities and differences. However, little attention has been paid to illustrate the differences in efficacy from the perspective of phytochemistry. In this study, ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry (UPLC-Q-Exactive-Orbitrap-MS) was used to qualitatively analyze the ingredients in 4 herbs. A total of 86 compounds were plausibly or unambiguously identified, there were 54 common components among the 4 medicinal materials, and each kind of medicinal materials had its own unique components. On the basis of qualitative analysis, ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-QQQ-MS/MS) was used to quantitatively analyze 31 components contained in 4 medicinal materials, and principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA) and other multivariate statistical analysis were furtherly performed for comparing the component contents. The results showed that the samples from the same parts were clustered into one group, and the samples from different medicinal parts were significantly different. The analysis of variable importance projection (VIP) value of the OPLS-DA model showed that 10 components including chlorogenic acid, secologanic acid, isochlorogenic acid A, loganin, lonicerin, loganic acid, secoxyloganin, sweroside, luteolin and rhoifolin were the main difference components among the 4 medicinal materials. The study not only lays a solid foundation for the intrinsic quality control of 4 medicinal materials and the study of different effects of the 4 medicinal materials at the phytochemical level, but also provides a basis for more rational utilization of various parts of L. japonica and expansion of medicinal resources.

The pharmacological mechanism of Abelmoschus manihot in the treatment of chronic kidney disease

Abelmoschus manihot (A.manihot) is a herbaceous flowering medicinal plant and flavonoids are its main pharmacological active ingredients. A.manihot is listed in the 2020 edition of the Chinese Pharmacopoeia for the treatment of chronic kidney disease (CKD). A.manihot significantly reduces proteinuria in CKD, and the effectiveness and safety of A.manihot in the treatment including primary glomerulonephropathy and diabetic kidney disease (DKD) have been proved by several randomized controlled trials (RCT). Emerging pharmacological studies have explored the potential active small molecules and the underlying mechanisms in A.manihot. The active constituents of A.manihot are mainly seven flavonoids, including hibifolin, hyperoside, isoquercetin, rutin, quercetin, myricetin, and quercetin-3-O-robinobioside. The mechanisms of action mainly include alleviating renal fibrosis, reducing the inflammatory response and decreasing the apoptosis of podocytes. In this review, we summarize the updated information of active components and molecular mechanisms of A.manihot on chronic kidney disease.

Evidence construction of Huangkui capsule against chronic glomerulonephritis: A systematic review and network pharmacology

BACKGROUND

Chronic glomerulonephritis (CGN) is a relatively common primary glomerular disease. Huangkui capsule (HKC) combined with angiotensin receptor blocker (ARB) for CGN is frequently used in clinical practice, however, there is still lack of high-quality evidence-based evidence and network pharmacology to clarify the therapeutic efficacy and pharmacological mechanisms.

PURPOSE

Integrating evidence-based medicine and network pharmacology to explain the therapeutic efficacy and pharmacological mechanisms of ARB combined with HKC for CGN.

METHODS

Studies matching the topic were searched from PubMed, Web of Science, Embase database, the Cochrane Library, Chinese National Knowledge Infrastructure, CBM databases, the VIP medicine information system and the Wanfang database and screened according to inclusion and exclusion criteria. The data of the included studies were meta-analyzed by blood urea nitrogen (BUN), serum creatinine (SCR), 24-h urine protein (24hUP) and effective rate (ER). A meta-analysis of the data from the included studies was performed. Then, based on the network pharmacology, the chemical ingredients in HKC and their targets of action, disease targets, common targets and other relevant information were screened, and the key pathways were relevantly annotated based on bioinformatics technology to explore the potential mechanisms of HKC and ARB for CGN.

RESULTS

The results showed that SCR index (p < 0.05), 24hUP index (p < 0.001) in the group treated with HKC and ARB were significantly lower than those in the control group. BUN index in the group treated with HKC and VAL were significantly lower than those in the control group (p < 0.001). Effective rate index in the group treated with HKC and ARB was significantly higher than those in the control group (p < 0.001). There was no significant difference in BUN treated with IRB, LOS, and TEL (p = 0.181; p = 0.811; p = 0.067). Based on network pharmacology, the results were as follows: The PPI network indicated that STAT3, AKT1, MAPK1, TP53 and JUN were key target proteins. The results of KEGG analysis suggested that the pharmacological mechanisms were mainly associated with AGE-RAGE signaling pathway in diabetic complications.

CONCLUSION

The combination of ARB and HKC can achieve better therapeutic effects in the treatment of CGN, meanwhile, ARB and HKC have a significant improved effectiveness in the treatment of CGN compared with ARB or HKC alone. In addition, HKC and ARB synergistically treated CGN through a multi-pathway network.

On the use of a 2D-carbon microfiber fractionation system to improve flow-injection QTOF-HRMS analysis in complex matrices: the case of Abelmoschus manihot flower extracts

A two-dimensional microscale carbon fiber/active carbon fiber system combined with a quadrupole time of flight high-resolution mass spectrometry (2DμCFs-QTOF-HRMS) system is proposed for the rapid putative identification of polar, medium-polar and weakly polar constituents in complex matrices while strongly mitigating ionic suppression effects. The capabilities of 2DμCFs-QTOF-HRMS have been proven by analysing the composition of Abelmoschus manihot flower extracts, allowing, in a single run, the detection of 41 known substances and the presence of 6 compounds never revealed before in these samples. 2DμCFs-QTOF-HRMS has been compared with traditional HPLC-MS, showing higher versatility and a significant reduction of both analysis time (70 min to 5 min) and solvent consumption (35 mL to 1.5 mL). A comparison with the results obtained by direct flow-injection MS analyses demonstrated that 2DμCFs-QTOF-HRMS leads to a more comprehensive analysis and to improved detection sensitivity. The proposed method can be considered suitable for the rapid and comprehensive analysis of food, environmental and pharmaceutical complex samples. 2DμCFs-QTOF-HRMS can thus be considered a rapid, versatile, reliable, high-throughput and economical technique that allows for the collection of information on polar, semipolar, and weakly polar components in complex matrices.