Rapid identification of new minor chemical constituents from Smilacis Glabrae Rhizoma by combined use of UHPLC-Q-TOF-MS, preparative HPLC and UHPLC-SPE-NMR-MS techniques

Chemical detection and analysis of Astragalus-Cassia twig drug pair using UHPLC-Q-TOF-MS and HPLC-UV methods

The classic Astragalus-Cassia twig drug pair has a long history of proven efficacy. However, a fewer studies on material basis of the Astragalus and Cassia twig decoction (ACD) was researched at present. The method of UPLC-Q-TOF-MS for classifying and identifying the main chemical components of ACD was established and the differences in composition between single decoction and co-decoction were compared by using HPLC-UV. The therapeutic role of ACD on type 2 diabetes (T2D) rats was investigated. Thirty-five compounds were resolved from the ACD. Fifteen compounds were deduced from the decoction of Astragalus, whereas nine compounds were identified from Cassia twig. Pairing of herbs make a significant effect on the chemical composition of herbal decoction. ACD can play a more obvious role in alleviating the symptoms of T2D rats, compared to the application of single herb.

Therapeutic effects of Zhuling Jianpi capsule on experimental ulcerative colitis and characterization of its chemical constituents and metabolomics using UHPLC-Q-TOF-MS

Zhuling Jianpi Capsule (Zhuling) is a traditional Chinese medicinal formula used to treat symptoms such as abdominal pain, bloating and diarrhea associated with inflammatory bowel disease (IBD). However, the protective effects of Zhuling on experimental ulcerative colitis (UC) and the effective substance responsible for its efficacy have rarely been reported. In this study, we evaluated the therapeutic effects of orally administrated Zhuling on DSS-induced UC in mice. The chemical constituents and metabolomics of Zhuling were qualitatively analyzed by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). The results showed that Zhuling treatment markedly alleviated DSS-induced clinical symptoms, restrained the secretion of pro-inflammatory cytokines, and improved intestinal epithelial barrier function. Furthermore, a total of 167 compounds have been identified or characterized, and 120 prototype components were detected in the urine, plasma, bile and feces of mice. Among them, altogether 26 representative prototypes were associated with 139 metabolites via the corresponding biotransformation pathways, and both of them mainly contained flavonoids, alkaloids, organic acids, monoterpenes, phenylpropanoids, triterpenoids, sesquiterpenoids and anthraquinones. Finally, 12 potent compounds mainly containing flavonoids, terpenoids and phenylpropanoids were screened out as potential quality control index components and might be the main substances that exert a pharmacological effect. Our data indicated that Zhuling administration prominently alleviates DSS-induced colitis in mice. Additionally, the chemical and metabolic profiling provided helpful information on the potential pharmacodynamic substances of Zhuling, which can be further investigated in the future.

Influence of heat processing on the anti-inflammatory activity of fresh Smilax glabra based on PDE4 inhibition

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Heat processing plays a key role in chemical profiles and health benefits of fresh SG.

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Fresh SG exhibits significant anti‐inflammatory effect based on PDE4 inhibition.

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The heat-labile quality and safety aspects of four astilbin isomers are compared.

Smilax glabra Roxb. (SG) is widely used as functional food with various beneficial effects. Fresh SG without processing has been eaten directly for anti-inflammation from ancient China, while the underlying mechanism remains underexplored. This study aims to investigate the anti-inflammatory activity of fresh SG by using metabolites profiles, affinity ultrafiltration mass spectrometry, PDE4 enzyme inhibition assay, and in silico analysis. Encouragingly, fresh SG showed promising anti-inflammatory effect with IC₅₀ value (0.009 μg/μL) on PDE4 was about 12 times higher than that of processed SG (0.110 μg/μL). Astilbin was identified as the main bioactive compound of fresh SG responsible for PDE4 inhibitory activity. We found that heat processing strongly affected astilbin isomerization, leading to significant changes in contents and PDE4 inhibitory activities of four astilbin isomers, resulting in decreased anti-inflammatory activity of fresh SG. This finding will provide theoretical basis for systematic research and food/nutraceutical applications of fresh Smilax glabra in the future.

Insights into the Cardiotoxic Effects of Veratrum Lobelianum Alkaloids: Pilot Study

Jervine, protoveratrine A (proA), and protoveratrine B (proB) are Veratrum alkaloids that are presented in some remedies obtained from Veratrum lobelianum, such as Veratrum aqua. This paper reports on a single-center pilot cardiotoxic mechanism study of jervine, proA, and proB in case series. The molecular aspects were studied via molecular dynamic simulation, molecular docking with cardiac sodium channel Na_V1.5, and machine learning-based structure–activity relationship modeling. HPLC-MS/MS method in combination with clinical events were used to analyze Veratrum alkaloid cardiotoxicity in patients. Jervine demonstrates the highest docking score (−10.8 kcal/mol), logP value (4.188), and pK_a value (9.64) compared with proA and proB. Also, this compound is characterized by the lowest calculated IC₅₀. In general, all three analyzed alkaloids show the affinity to Na_V1.5 that highly likely results in cardiotoxic action. The clinical data of seven cases of intoxication by Veratrum aqua confirms the results of molecular modeling. Patients exhibited nausea, muscle weakness, bradycardia, and arterial hypotension. The association between alkaloid concentrations in blood and urine and severity of patient condition is described. These experiments, while primary, confirmed that jervine, proA, and proB contribute to cardiotoxicity by Na_V1.5 inhibition.

Determination of Alkaloids and Flavonoids in Sophora flavescens by UHPLC-Q-TOF/MS

This study is based on UHPLC-Q-TOF/MS and fragment ions to achieve classification and identification of alkaloids and flavonoids in Sophora flavescens. By reviewing the available and relevant literature, the mass fragmentation rules of alkaloids and flavonoids were summarized. 0.1% formic acid water (A) and acetonitrile (B) were used as mobile phases. 37 chemical constituents were identified, including 13 alkaloids and 24 flavonoids. This research method offers a complete strategy based on the fragmentation information of characteristic fragment ions and neutral loss obtained by MS/MS to characterize the chemical composition of Sophora flavescens.

Antioxidant and Anti-Inflammatory Activities of Six Flavonoids from Smilax glabra Roxb

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, ¹H NMR and ¹³C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (−)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS⁺) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1β, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (−)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS⁺ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1β, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra.

Chemical profiles, antioxidant activity and acute toxicity of raw and sulfur-fumigated Smilacis Glabrae Rhizoma

ETHNOPHARMACOLOGICAL RELEVANCE

Smilacis Glabrae Rhizoma (SGR), known as Tu-fu-ling in the China, Japan and Korea, is an herb that has been used for clearing damp and detoxification in traditional Chinese medicine for many years. The post-harvest drying of SGR has traditionally been done by the sun, but sometimes sulfur fumigation is used instead due to its low cost and high efficiency. Recent reports show that sulfur fumigation can change the chemical constitution of herbal medicines and decrease their biology activity.

AIM OF THE STUDY

This study will investigate the changes to the chemical constitution, acute toxicity and antioxidant potential of SGR that occur after sulfur fumigation. To date, no studies have investigated these aspects simultaneously.

MATERIALS AND METHODS

An ultra-performance liquid chromatography fingerprint method was developed for analysing changes to SGR's chemical constitution caused by sulfur fumigation. The chromatography conditions were as follows: all samples were analysed on a Waters Acquity UHPLC HT3 C18 column; the linear gradient elution was conducted with a mobile phase prepared from acetonitrile and water. All calibration curves showed good linear regression (R > 0.9991) within the tested range. The method was validated for precision, accuracy, limit of detection and quantification. Total flavonoids of the raw and sulfur-fumigated samples were also determined by ultraviolet spectrophotometry. The antioxidant properties of the extracts were evaluated using both DPPH and ABTS radical scavenging assays. The acute toxicities of the raw and sulfur-fumigated samples were investigated.

RESULTS

The results demonstrate that the amounts of astilbin, neoastilbin, neoisoastilbin, isoastilbin, resveratrol and total flavonoids were lower in sulfur-fumigated samples than in raw samples. The antioxidant activity of the sulfur-fumigated samples was also significantly lower. Therefore, sulfur fumigation may cause chemical transformation, alter the chemical constitution, and decrease the bioactivity of SGR. Orally-administered doses did not cause mortality or changes in the general behaviour of tested mice. The LD50 was > 5000 mg/kg DW. However, the high-dose S-SGR mice had significant liver damage and high levels of plasma biochemical parameters (ALT, AST, DBIL, TBIL).

CONCLUSIONS

The results of the current study suggest that sulfur fumigation can decrease antioxidant activity in vitro; and that orally-administrated S-SGR is unsafe at doses > 3000 mg/kg dried materia medica. Therefore, sulfur-fumigation processing should be forbidden for SGR until its efficacy and safety has been demonstrated. An alternative method of sulfur fumigation for the post-harvest processing of SGR should also be developed.

Recent development in mass spectrometry and its hyphenated techniques for the analysis of medicinal plants

INTRODUCTION

Medicinal plants are gaining increasing attention worldwide due to their empirical therapeutic efficacy and being a huge natural compound pool for new drug discovery and development. The efficacy, safety and quality of medicinal plants are the main concerns, which are highly dependent on the comprehensive analysis of chemical components in the medicinal plants. With the advances in mass spectrometry (MS) techniques, comprehensive analysis and fast identification of complex phytochemical components have become feasible, and may meet the needs, for the analysis of medicinal plants.

OBJECTIVE

Our aim is to provide an overview on the latest developments in MS and its hyphenated technique and their applications for the comprehensive analysis of medicinal plants.

METHODOLOGY

Application of various MS and its hyphenated techniques for the analysis of medicinal plants, including but not limited to one-dimensional chromatography, multiple-dimensional chromatography coupled to MS, ambient ionisation MS, and mass spectral database, have been reviewed and compared in this work.

RESULTS

Recent advancs in MS and its hyphenated techniques have made MS one of the most powerful tools for the analysis of complex extracts from medicinal plants due to its excellent separation and identification ability, high sensitivity and resolution, and wide detection dynamic range.

CONCLUSION

To achieve high-throughput or multi-dimensional analysis of medicinal plants, the state-of-the-art MS and its hyphenated techniques have played, and will continue to play a great role in being the major platform for their further research in order to obtain insight into both their empirical therapeutic efficacy and quality control.

Rapid discrimination of raw and sulfur-fumigated Smilax glabra based on chemical profiles by UHPLC-QTOF-MS/MS coupled with multivariate statistical analysis

Smilax glabra (SG) is commonly used as a traditional edible herb in eastern Asia. Recently, sulfur-fumigation has been frequently used in order to obtain better color and a longer storage lifetime. However, the chemical alterations caused by this process remain unknown. The aim of this research was to explore potential chemical differences between non-fumigated and sulfur-fumigated SG samples. A novel approach was developed by using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) with principal component analysis (PCA) and orthogonal partial squared discriminant analysis (OPLS-DA). Fifty-eight compounds were unambiguously characterized or tentatively identified in the chemical profiles for the first time. Six newly generated sulfur-containing compounds, namely glucosyringic acid sulfate, 5-O-caffeoylshikimic acid sulfite, 3-O-caffeoylshikimic acid sulfite, 5-O-caffeoylshikimic acid sulfate, 3-O-caffeoylshikimic acid sulfate and astilbin sulfate, were screened out to be the most characteristic markers for distinguishing non-fumigated and sulfur-fumigated SG. This newly proposed approach can not only be applied for exploring chemical markers but can also be used to investigate the chemical transformation mechanism associated with sulfur for other edible herbs.

HPLC-PDA-MS/MS Characterization of Bioactive Secondary Metabolites from Turraea fischeri Bark Extract and Its Antioxidant and Hepatoprotective Activities In Vivo

Turraea fischeri is an East African traditional herb, which is widely used in traditional medicine. In this study, we profiled the secondary metabolites in the methanol extract of T. fischeri bark using HPLC-PDA-ESI-MS/MS, and 20 compounds were tentatively identified. Several isomers of the flavonolignan cinchonain-I and bis-dihydroxyphenylpropanoid-substituted catechin hexosides dominated the extract. Robust in vitro and in vivo antioxidant properties were observed in 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay (DPPH) and ferric reducing antioxidant power (FRAP) assay, and in the model organism Caenorhabditis elegans. Additionally, the extract exhibited promising hepatoprotective activities in D-galactosamine (D-GaIN) treated rats. A significant reduction in the elevated levels of aspartate aminotransferase (AST), total bilirubin, gamma-glutamyltransferase (GGT), and malondialdehyde (MDA) and increase of glutathione (GSH) was observed in rats treated with the bark extract in addition to D-galactosamine when compared with rats treated with D-galactosamine alone. In conclusion, T. fischeri is apromising candidate for health-promoting and for pharmaceutical applications.

Sensitivity enhancement by chromatographic peak concentration with ultra-high performance liquid chromatography-nuclear magnetic resonance spectroscopy for minor impurity analysis

High performance liquid chromatography can be coupled with nuclear magnetic resonance (NMR) spectroscopy to give a powerful analytical method known as liquid chromatography-nuclear magnetic resonance (LC-NMR) spectroscopy, which can be used to determine the chemical structures of the components of complex mixtures. However, intrinsic limitations in the sensitivity of NMR spectroscopy have restricted the scope of this procedure, and resolving these limitations remains a critical problem for analysis. In this study, we coupled ultra-high performance liquid chromatography (UHPLC) with NMR to give a simple and versatile analytical method with higher sensitivity than conventional LC-NMR. UHPLC separation enabled the concentration of individual peaks to give a volume similar to that of the NMR flow cell, thereby maximizing the sensitivity to the theoretical upper limit. The UHPLC concentration of compound peaks present at typical impurity levels (5.0-13.1 nmol) in a mixture led to at most three-fold increase in the signal-to-noise ratio compared with LC-NMR. Furthermore, we demonstrated the use of UHPLC-NMR for obtaining structural information of a minor impurity in a reaction mixture in actual laboratory-scale development of a synthetic process. Using UHPLC-NMR, the experimental run times for chromatography and NMR were greatly reduced compared with LC-NMR. UHPLC-NMR successfully overcomes the difficulties associated with analyses of minor components in a complex mixture by LC-NMR, which are problematic even when an ultra-high field magnet and cryogenic probe are used.

Rhizoma Smilacis Glabrae inhibits pathogen-induced upper genital tract inflammation in rats through suppression of NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma Smilacis Glabrae (RSG) is traditionally used to treat gynecological disease, which is simply recorded in Chinese Pharmacopoeia. However, whether it has effect on upper genital tract inflammation (UGTI) is unclear.

AIM OF THE STUDY

To evaluate the pharmacological effect of RSG on UGTI in rats and analyze its phytochemistry characteristics.

MATERIALS AND METHODS

The substances in RSG extract was qualified by LC-Q-TOF-MS method, and 11 substances were further quantified. The RSG extract, at dose of 241, 482 (clinical dose) and 964mg/kg/day, was orally administered to UGTI rats whose upper genital tracts were multi-infected with pathogens. Infiltrations of neutrophil and lymphocyte and productions of IL-1β, IL-6, CXCL-1, MCP-1, RANTES, PGE2, COX-2, NF-κB p65 and IκB-α in upper genital tract were examined to evaluate the effects of RSG and its potential mechanism.

RESULTS

A total of 77 substances were detected in RSG extract, with 50 substances putatively identified, most of which were flavonoids, phenolic acids and phenylpropanoids. The quantification analysis showed flavonoid had a relative high amount. In pharmacological study, RSG extract suppressed infiltrations of inflammatory cells, reduced over-productions of factors involved in inflammation and pelvic pain. A potential mechanism of these effects was blocking NF-κB signal pathway.

CONCLUSIONS

The RSG extract exhibited anti-inflammatory effect on UGTI, with a potential mechanism of blocking the activation of NF-κB signal pathway. The effect may be involved in the presence of substances, such as flavonoids and phenolic acids.

How close are we to complete annotation of metabolomes?

The metabolome describes the full complement of the tens to hundreds of thousands of low molecular weight metabolites present within a biological system. Identification of the metabolome is critical for discovering the maximum amount of biochemical knowledge from metabolomics datasets. Yet no exhaustive experimental characterisation of any organismal metabolome has been reported to date, dramatically contrasting with the genome sequencing of thousands of plants, animals and microbes. Here, we review the status of metabolome annotation and describe advances in the analytical methodologies being applied. In part through new international coordination, we conclude that we are now entering a new era of metabolome annotation.