Characterization and profiling of phenolic amides from Cortex Lycii by ultra-high performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry

Plant-derived and dietary phenolic cinnamic acid derivatives: Anti-inflammatory properties

Cinnamic acids are aromatic acids primarily found in plants and plant-derived food. Phenolic cinnamic acids, with one or more hydroxyl groups in the aromatic ring, often contribute to the biological activities attributed to these compounds. The presence of hydroxyl groups and a carboxyl group makes cinnamic acids very hydrophilic, preventing them from crossing biological membranes and exerting their biological activities. To alleviate this condition, a panel of synthetic modifications have been made leading to a diverse set of phenolic cinnamic structures. In this review, an overview of the natural phenolic cinnamic acid derivatives and their plant sources (more than 200) is described. The synthetic approaches to obtain the referred derivatives (more than 200) namely esters and amides are reviewed. Further, their anti-inflammatory activity (more than 70 compounds) is scrutinized. Finally, future directions will be indicated to translate the research on phenolic cinnamic derivatives into potentially effective anti-inflammatory drugs.

Contribution of phenolamides to the quality evaluation in Lycium spp

ETHNOPHARMACOLOGICAL RELEVANCE

Goji berry is a general term for various plant species in the genus Lycium. Goji has long been historically used in traditional Chinese medicines. Goji is a representative tonic medicine that has the effects of nourishing the liver and kidney and benefiting the essence and eyesight. It has been widely used in the treatment of various diseases, including tinnitus, impotence, spermatorrhea and blood deficiency, since ancient times.

AIM OF THE REVIEW

This study aims to comprehensively summarize the quality evaluation methods of the main compounds in goji, as well as the current research status of the phenolamides in goji and their pharmacological effects, to explore the feasibility of using phenolamides as quality control markers and thus improve the quality and efficacy in goji.

MATERIALS AND METHODS

Relevant literature from PubMed, Web of Science, Science Direct, CNKI and other databases was comprehensively collected, screened and summarized.

RESULTS

According to the collected literature, the quality evaluation markers of goji in the Pharmacopoeia of the People's Republic of China are Lycium barbarum polysaccharide (LBP) and betaine. As a result of its structure complexity, only the total level of LBP can be determined, while betaine is not prominent in the pharmacological action of goji and lacks species distinctiveness. Neither of them can well explain the quality of goji. KuA and KuB are commonly used as quality evaluation markers of the Lycii cortex because of their high levels and suitable pharmacological activity. Goji is rich in polyphenols, carotenoids and alkaloids. Many studies have used the above compounds to establish quality evaluation methods but the results have not been satisfactory. Phenolamides have often been neglected in previous studies because of their low single compound levels and high separation difficulty. However, in recent years, the favorable pharmacological activities of phenolamides have been gradually recognized, and studies on goji phenolamides are greatly increasing. In addition, phenolamides have higher species distinctiveness than other compounds and can be combined with other compounds to better evaluate the quality of goji to improve its average quality.

CONCLUSIONS

The phenolamides in the goji are rich and play a key role in antioxidation, anti-inflammation, neuroprotection and immunomodulation. As a result of their characteristics, it is suitable to evaluate the quality by quantitative analysis of multi-components by single-marker and fingerprint. This method can be combined with other techniques to improve the quality evaluation system of goji, which lays a foundation for their effectiveness and provides a reference for new quality evaluation methods of similar herbal medicines.

Integrating UPLC-MS/MS with in Silico and in Vitro Screening Accelerates the Discovery of Active Compounds in Stephania epigaea

Traditional Chinese medicines (TCMs) are popular in clinic because of their safety and efficacy. They contain abundant natural active compounds, which are important sources of new drug discovery. However, how to efficiently identify active compounds from complex ingredients remains a challenge. In this study, a method combining UHPLC-MS/MS characterization and in silico screening was developed to discover compounds with dopamine D2 receptor (D2R) activity in Stephania epigaea (S. epigaea). By combining the compounds identified in S. epigaea by UHPLC-MS/MS with reported compounds, a virtual library of 80 compounds was constructed for in silico screening. Potentially active compounds were chosen based on screening scores and subsequently tested for in vitro activity on a transfected cell line CHO-K1-D2 model using label-free cellular phenotypic assay. Three D2R agonists and five D2R antagonists were identified. (-)-Asimilobine, N-nornuciferine and (-)-roemerine were reported for the first time as D2R agonists, with EC50 values of 0.35 ± 0.04 μM, 1.37 ± 0.10 μM and 0.82 ± 0.22 μM, respectively. Their target specificity was validated by desensitization and antagonism assay. (-)-Isocorypalmine, (-)-tetrahydropalmatine, (-)-discretine, (+)-corydaline and (-)-roemeroline showed strong antagonistic activity on D2R with IC50 values of 92 ± 9.9 nM, 1.73 ± 0.13 μM, 0.34 ± 0.02 μM, 2.09 ± 0.22 μM and 0.85 ± 0.08 μM, respectively. Their kinetic binding profiles were characterized using co-stimulation assay and they were both D2R competitive antagonists. We docked these ligands with human D2R crystal structure and analyzed the structure-activity relationship of aporphine-type D2R agonists and protoberberine-type D2R antagonists. These results would help to elucidate the mechanism of action of S. epigaea for its analgesic and sedative efficacy and benefit for D2R drug design. This study demonstrated the potential of integrating UHPLC-MS/MS with in silico and in vitro screening for accelerating the discovery of active compounds from TCMs.

Protective effect of phenylpropionamides in the seed of Cannabis Sativa L. on Parkinson's disease through autophagy

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world. As one of the major degradation pathways, autophagy plays a pivotal role in maintaining the effective turnover of proteins and damaged organelles in cells. Lewy bodies composed of α-synuclein (α-syn) abnormally aggregated in the substantia nigra are important pathological features of PD, and autophagy dysfunction is considered to be an important factor leading to abnormal aggregation of α-syn. Phenylpropionamides (PHS) in the seed of Cannabis sativa L. have a protective effect on neuroinflammation and antioxidant activity. However, the therapeutic role of PHS in PD is unclear. In this study, the seeds of Cannabis sativa L. were extracted under reflux with 60% EtOH-H2O, and the 60% EtOH-H2O elution fraction was identified as PHS with the UPLC-QTOF-MS. The 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP)-induced PD model in C57BL/6 J mice was used for behavioral and pharmacodynamic experiments. Behavioral symptoms were improved, Nissl-stained and TH-positive neurons in the substantia nigra were significantly increased in PHS-treated MPTP-induced PD model mice. Compared with the model group, PHS treatment reduced the expression level of α-syn, and the expression of TH increased significantly by western blotting, compared with the model group, the PHS group suppressed Caspase 3 and Bax expression and promoted Bcl-2 expression and levels of p62 decreased significantly, the ratio of LC3-II/I and p-mTOR/mTOR in the PHS group had a downward trend, suggesting that the therapeutic effect of PHS on MPTP-induced PD model mice may be triggered by the regulation of autophagy.

Protective effects of Lycium barbarum L. berry extracts against oxidative stress-induced damage of the retina of aging mouse and ARPE-19 cells

In this study, we investigated the preventive effect of Lycium barbarum L. berry extract on age-related macular degeneration (AMD) and the main components responsible for its antioxidant activity. An AMD mouse model was developed by feeding 18-month-old mice with a 1% hydroquinone diet. Meanwhile, the model mice were treated with water extract (LBW) and alcohol extract (LBE) of L. barbarum berries respectively for 3 months. It was found that the retinal structural abnormalities were improved and the oxidation stress and inflammatory imbalance were both attenuated in model mice treated with the extracts of L. barbarum berries. According to the metabolomics analysis of the serum of model mice, LBW regulated the metabolism of unsaturated fatty acids and sphingolipids, while LBE extracts tended to regulate taurine metabolism. On sodium iodate induced oxidative injury of ARPE-19 cells, water extracts of L. barbarum berries eluted with 95% ethanol (LBW-95E) on AB-8 macroporous resin significantly improved the cell viability and attenuated oxidative stress by increasing the superoxide dismutase (SOD) activity and glutathione (GSH) content, decreasing the reactive oxygen species (ROS) content, promoting the entry of nuclear factor erythroid-derived 2-like 2 (Nrf2) into the nucleus and up-regulating the heme oxygenase-1 (HO-1) expression. Scopoletin, N-trans-feruloyltyramine and perlolyrine were identified as the main components of LBW-95E. These results demonstrated that L. barbarum berry extracts protected the retina of aging AMD model mice from degeneration and LBW-95E was the vital antioxidant activity fraction of LBW. These findings suggest that L. barbarum berry extracts might be an excellent natural source for the development of retinal protection-related drugs or dietary supplements.

Kukoamine B from Lycii Radicis Cortex Protects Human Keratinocyte HaCaT Cells through Covalent Modification by Trans-2-Nonenal

The unsaturated aldehyde trans-2-nonenal is known to be generated by lipid peroxidation at the surface of the skin in an aging-related manner and has harmful effects on keratinocytes in the skin. In this study, the protective effect of a Lycii Radicis Cortex (LRC) extract against trans-2-nonenal-induced cell damage on human keratinocyte cell lines (HaCaT) was investigated. Notably, treatment with the LRC extract resulted in an increase in cell survival, while trans-2-nonenal decreased the viability of HaCaT cells. For identification of interaction between the LRC extract and trans-2-nonenal, this mixture was incubated in simulated physiological conditions, showing a strong decrease in the amount of trans-2-nonenal by the LRC extract. Subsequent LC-ESI-MS analysis revealed that kukoamine B (KB) formed Schiff base-derived pyridinium adducts with trans-2-nonenal. Thus, these results suggest that KB could be a potential agent that may protect HaCaT cells by forming new products with trans-2-nonenal.

Potential Antioxidative and Anti-Hyperuricemic Components Targeting Superoxide Dismutase and Xanthine Oxidase Explored from Polygonatum Sibiricum Red

Polygonatum sibiricum Red. (P. sibiricum) has been used as a traditional Chinese medicine with a wide range of pharmacology effects. However, the responsible bioactive compounds and their mechanisms of action concerning its antioxidative and anti-hyperuricemic activities remain unexplored. In this work, the antioxidant capacity of P. sibiricum was firstly evaluated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azinobis-(3ethylbenzthiazoline)-6-sulfonic acid (ABTS) and ferric-reducing antioxidant power (FRAP) assays, from which the ethyl acetate (EA) fraction exhibited the highest DPPH, ABTS radical scavenging, and ferric-reducing capacities. Meanwhile, the EA fraction displayed the highest total phenolic and flavonoid contents among the four fractions. Next, the potential ligands from the EA fraction were screened out by bio-affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC-MS) with superoxide dismutase (SOD) and xanthine oxidase (XOD). As a result, N-trans-p-coumaroyloctopamine, N-trans-feruloyloctopamine, N-trans-feruloyltyramine were identified as potential SOD ligands, while N-cis-p-coumaroyltyramine was determined as potential XOD ligand. Additionally, these four ligands effectively interact with SOD and XOD in the molecular docking analysis, with binding energies (BEs) ranging from –6.83 to –6.51 kcal/mol, and the inhibition constants (Ki) from 9.83 to 16.83 μM, which were better than the positive controls. In conclusion, our results indicated that P. sibiricum has good antioxidative and anti-hyperuricemic activities, and its corresponding active ligands targeting SOD and XOD could be explored by the UF-LC-MS method.

Goji Berries Supplementation in the Diet of Rabbits and Other Livestock Animals: A Mini-Review of the Current Knowledge

In the last decades, several nutraceutical substances have received great attention for their potential role in the prevention and treatment of different diseases as well as for their beneficial effects in promoting the health of humans and animals. Goji berries (GBs) are the fruit of Lycium barbarum and other species of Lycium, used in traditional Chinese medicine, and they have recently become very popular in the Occidental world because of their properties, such as anti-aging, antioxidant, anticancer, neuroprotective, cytoprotective, antidiabetic, and anti-inflammatory activities. These effects are essentially evaluated in clinical trials in humans; in experimental animal models, such as mice and rats; and in cell lines in in vitro studies. Only recently has scientific research evaluated the effects of GBs diet supplementation in livestock animals, including rabbits. Although studies in the zootechnical field are still limited and the investigation of the GB mechanisms of action is in an early stage, the results are encouraging. This review includes a survey of the experimental trials that evaluated the effects of the GBs supplementation on reproductive and productive performances, immune system, metabolic homeostasis, and meat quality principally in the rabbit with also some references to other livestock animal species. Evidence supports the idea that GB supplementation could be used in rabbit breeding, although future studies should be conducted to establish the optimal dose to be administered and to assess the sustainability of the use of GBs in the diet of the rabbit.

The integrated study on the chemical profiling and in vivo course to explore the bioactive constituents and potential targets of Chinese classical formula Qingxin Lianzi Yin Decoction by UHPLC-MS and network pharmacology approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Qingxin Lianzi Yin Decoction (QXLZY), a Chinese classical formula, has been widely used in the treatment of various chronic kidney diseases over 1,000 years. However, the current studies on QXLZY were mostly focused on its clinical efficacy, lacking systematic material basis research on constituents.

AIM OF THE STUDY

This work aims to elucidate and quantify the chemical constituents, clarify the blood-absorbed components and excretion pathways, predict major bioactive constituents and discover potential therapeutic targets.

MATERIALS AND METHODS

UHPLC-LTQ-Orbitrap HRMS was employed to clarify the chemical constituents and metabolites of QXLZY. The extraction of diagnostic ion and neutral loss fragment was aimed for searching specific type of constituents. The plasma, urine, bile and feces samples of rats after oral administration of QXLZY were systematically studied. UHPLC-QQQ-MS/MS was employed to simultaneously detect different types of constitutes. Based on the analysis of ingredients in vivo, the bioactive constituents and potential therapeutic targets in the treatment of diabetic nephropathy (DN) was investigated by using network pharmacological analysis.

RESULTS

Totally, 220 compounds were identified or tentatively characterized by UHPLC-LTQ-Orbitrap HRMS. Among them, 59 compounds were confirmed by reference standards. Meanwhile, 21 representative components were simultaneously determined within 15 min by UHPLC-QQQ-MS/MS. 123 components (74 prototypes as well as 49 metabolites) were identified or tentatively characterized. By using network pharmacological analysis, baicalein, liquiritigenin, succinic acid, formononetin, wogonin might be the major effective constituents in QXLZY during the treatment of DN.

CONCLUSIONS

Flavonoids, saponins and organic acids were the major chemical ingredients of QXLZY. Flavonoids were the main components absorbed into blood, followed by organic acids. Phase II conjugation reaction was the major metabolic type. The pathways that QXLZY in the treatment of DN were probably related to glucose and lipid metabolism, oxidative stress and inflammation.

The Chemistry and Health Benefits of Dietary Phenolamides

Phenolamides, also known as hydroxycinnamic acid amides or phenylamides, have been reported throughout the plant kingdom, while a few of these amine-conjugated hydroxycinnamic acids are unique in foods. The current knowledge of their specific functions in plant development and defense is readily available as is their biosynthesis; however, their functionality in humans is still largely unknown. Of the currently known phenolamides, the most common are avenanthramides, which are unique in oats and similar to the well-known drug Tranilast, which possess anti-inflammatory, antioxidant, anti-itch, and antiatherogenic activities. While recent data have brought to light more information regarding the other known phenolamides, such as hordatines, dimers of agmatine conjugated to hydroxycinnamic acid, and kukoamines, spermine-derived phenolamides, the information is still severely limited, leaving their potential health benefits to speculation. Herein, to highlight the importance of dietary phenolamides to human health, we review and summarize the four major subgroups of phenolamides, including their chemical structures, dietary sources, and reported health benefits. We believe that the studies on phenolamides are still in the infancy stage and additional health benefits of these phenolamides may yet be identified.

Phenolic Amides with Immunomodulatory Activity from the Nonpolysaccharide Fraction of Lycium barbarum Fruits

The fruits of Lycium barbarum have a long history as an edible and medicinal food in Asian regions and have multiple consumption methods; the polysaccharides (LBPs) are commonly considered as their major immunological constituents. The current study revealed that the total phenolic amide moieties from L. barbarum fruits showed greater potential immunomodulatory activity in vivo than did LBPs. Through subsequent investigation on the immunological bioactive phenolic amides, three new phenolic amides, lyciumamides L-N (1-3), as well as 12 analogues, were obtained from the total phenolic amide fraction. Extensive spectroscopic methods were used to elucidate the new structures. Compounds 4-6 and 15 significantly promoted LPS-stimulated B splenocyte, while compounds 4-6 displayed accelerative effects on the proliferation of Con A-stimulated T lymphocytes at a concentration of 20.0 μg/mL. These data indicated that extracts from L. barbarum fruits enriched with phenolic amides could be developed as a nutritional dietary supplement for immunocompromised individuals.

Hempseed Lignanamides Rich-Fraction: Chemical Investigation and Cytotoxicity towards U-87 Glioblastoma Cells

The weak but noteworthy presence of (poly)phenols in hemp seeds has been long overshadowed by the essential polyunsaturated fatty acids and digestible proteins, considered responsible for their high nutritional benefits. Instead, lignanamides and their biosynthetic precursors, phenylamides, seem to display interesting and diverse biological activities only partially clarified in the last decades. Herein, negative mode HR-MS/MS techniques were applied to the chemical investigation of a (poly)phenol-rich fraction, obtained from hemp seeds after extraction/fractionation steps. This extract contained phenylpropanoid amides and their random oxidative coupling derivatives, lignanamides, which were the most abundant compounds and showed a high chemical diversity, deeply unraveled through high resolution tandem mass spectrometry (HR-MS/MS) tools. The effect of different doses of the lignanamides-rich extract (LnHS) on U-87 glioblastoma cell line and non-tumorigenic human fibroblasts was evaluated. Thus, cell proliferation, genomic DNA damage, colony forming and wound repair capabilities were assessed, as well as LnHS outcome on the expression levels of pro-inflammatory cytokines. LnHS significantly inhibited U-87 cancer cell proliferation, but not that of fibroblasts, and was able to reduce U-87 cell migration, inducing further DNA damage. No modification in cytokines' expression level was found. Data acquired suggested that LnHS acted in U-87 cells by inducing the apoptosis machinery and suppressing the autophagic cell death.

Comparative Study of the Chemical Constituents and Bioactivities of the Extracts from Fruits, Leaves and Root Barks of Lycium barbarum

The fruits, leaves and root barks of L. barbarum plant are widely used as functional foods and as ingredients in traditional Chinese prescriptions and patent medicines. They are considered to have different pharmacological activities and health benefits because of their diverse constituents. Here, the chemical constituents of the extracts from fruits, leaves and root barks of L. barbarum were compared by ultra-high performance liquid chromatography coupled with high resolution mass spectrometry (UPLC-HR-MS). A total of 131 compounds were identified and seven of them were quantified. Among them, 98, 28 and 35 constituents were detected in fruits, leaves and root barks respectively. Dicaffeoylspermidine/spermine derivatives were the most detected compounds (74/131); among them, dicaffeoylspermine isomers and propionyl-dicaffeoylspermidine were found in root barks in very large amounts (e.g., kukoamine B = 10.90 mg/g dry powder); dicaffeoyl-spermidine isomers were detected in fruits/leaves in a high amount, and many of their glycosylated derivatives were mainly detected in fruits. In addition, six saponins from L. barbarum fruits were reported for the first time, and 5,6-dihydrosolasonine was reported for the first time in plants. The activity assays showed that the root bark extract possessed the strongest antioxidative activity and cytotoxicity, which was presumed due to the large amount of dicaffeoylspermine/spermidines in root barks. Fourteen potential bioactive components from fruits were identified by a target cell-based screening method. These results will help to understand the different biological activities of these three parts of L. barbarum plant and will benefit the discovery of new functional components.

Deep Annotation of Hydroxycinnamic Acid Amides in Plants Based on Ultra-High-Performance Liquid Chromatography-High-Resolution Mass Spectrometry and Its In Silico Database

Hydroxycinnamic acid amides (HCAAs), diversely distributed secondary metabolites in plants, play essential roles in plant growth and developmental processes. Most current approaches can be used to analyze a few known HCAAs in a given plant. A novel method for comprehensive detection of plant HCAAs is urgently needed. In this study, a deep annotation method of HCAAs was proposed on the basis of ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) and its in silico database of HCAAs. To construct an in silico UHPLC-HRMS HCAAs database, a total of 846 HCAAs were generated from the most common phenolic acid and polyamine/aromatic monoamine substrates according to possible biosynthesis reactions, which represent the structures of plant-specialized HCAAs. The characteristic MS/MS fragmentation patterns of HCAAs were extracted from reference mixtures. Four quantitative structure-retention relationship (QSRR) models were developed to predict retention times of mono-trans-HCAAs (aromatic amines conjugates), mono-trans-HCAAs (aliphatic amines conjugates), bis-HCAAs, and tris-HCAAs. The developed method was applied for identifying HCAAs in seeds (maize, wheat, and rice), roots (rice), and leaves (rice and tobacco). A total of 79 HCAAs were detected: 42 of them were identified in these plants for the first time, and 20 of them have never been reported to exist in plants. The results showed that the developed method can be used to identify HCAAs in a plant without prior knowledge of HCAA distributions. To the best of our knowledge, it is the first UHPLC-HRMS database developed for effective deep annotation of HCAAs from nontargeted UHPLC-HRMS data. It is useful for the identification of novel HCAAs in plants.

Use of UHPLC-TripleQ with synthetic standards to profile anti-inflammatory hydroxycinnamic acid amides in root barks and leaves of Lycium barbarum

Hydroxycinnamic acid amides (HCAA) are the secondary metabolites ubiquitously exist in flowering plants, formed by condensation between hydroxycinnamates and mono or polyamines. HCAA species not only serve multiple functions in plant growth and development, but also exert significant positive effects on human health. In this study, we combined organic synthesis and UPHLC-TripleQ-MS/MS specifically targeting at HCAA species. The method was fully validated with respect to specificity, linearity, intra- and inter-day precision and accuracy, limit of detection (LOD), limit of quantification (LOQ), recovery, and reproducibility. We applied this method to identify and quantify HCAAs from the root barks and leaves of Lycium barbarum. HCAA species were reported in leaves for the first time, and 10 new HCAA species were further identified in root barks in addition to the ones reported in the literature. We also examine anti-inflammatory properties of identified HCAAs species. Seven HCAA compounds had a potent NO inhibitory effect with IC₅₀ as low as 2.381 μM (trans-N-caffeoyl phenethylamine). Our developed method largely improved analytical sensitivity of HCAAs species that potentially contributes to plant metabolomics studies.

Recent (2000-2015) developments in the analysis of minor unknown natural products based on characteristic fragment information using LC-MS

Liquid chromatography-Mass Spectrometry (LC-MS) has been widely used in natural product analysis. Global detection and identification of nontargeted components are desirable in natural product research, for example, in quality control of Chinese herbal medicine. Nontargeted components analysis continues to expand to exciting life science application domains such as metabonomics. With this background, the present review summarizes recent developments in the analysis of minor unknown natural products using LC-MS and mainly focuses on the determination of the molecular formulae, selection of precursor ions, and characteristic fragmentation patterns of the known compounds. This review consists of three parts. Firstly, the methods used to determine unique molecular formula of unknown compounds such as accurate mass measurements, MSⁿ spectra, or relative isotopic abundance information, are introduced. Secondly, the methods improving signal-to-noise ratio of MS/MS spectra by manual-MS/MS or workflow targeting-only signals were elucidated; pure precursor ions can be selected by changing the precursor ion isolated window. Lastly, characteristic fragmentation patterns such as Retro-Diels-Alder (RDA), McLafferty rearrangements, "internal residue loss," and so on, occurring in the molecular ions of natural products are summarized. Classical application of characteristic fragmentation patterns in identifying unknown compounds in extracts and relevant fragmentation mechanisms are presented (RDA reactions occurring readily in the molecular ions of flavanones or isoflavanones, McLafferty-type fragmentation reactions of some natural products such as epipolythiodioxopiperazines; fragmentation by "internal residue loss" possibly involving ion-neutral complex intermediates). © 2016 Wiley Periodicals, Inc. Mass Spec Rev 37:202-216, 2018.

The Anticancer Activities Phenolic Amides from the Stem of Lycium barbarum

Four new phenolic amides, 4-O-methylgrossamide (1), (E)-2-(4,5-dihydroxy-2-{3-[(4-hydroxyphenethyl)amino]-3-oxopropyl}-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-N-(4-hydroxyphenethyl)acryl-amide (2), (Z)-lyciumamide C (3), (Z)-thoreliamide B (4), together with thirteen known phenolic amides were identified from the stem of Lycium barbarum. The structures of the new compounds were determined by spectroscopic methods. All compounds were evaluated for their anti-cancer activities against human glioma stem cell lines.

UHPLC/HR-ESI-MS/MS Profiling of Phenolics from Tunisian Lycium arabicum Boiss. Antioxidant and Anti-lipase Activities' Evaluation

This study was performed in the aim to evaluate nine different extracts from Tunisian Lycium arabicum for their total phenolic and total flavonoid contents, phytochemical analyses as well as their antioxidant and anti-lipase activities. The in vitro antioxidant property was investigated using three complementary methods (DPPH, ferric reducing antioxidant power (FRAP), and β-carotene-linoleic acid bleaching assays) while anti-lipase activity was evaluated using 4-methylumbelliferyl oleate method. From all of the tested extracts the most potent found to be the polar MeOH extracts especially those of stems and leaves. In order to investigate the chemical composition of these extracts and possible correlation of their constituents with the observed activities, an UHPLC/HR-ESI-MS/MS analysis was performed. Several compounds belonging to different chemical classes were tentatively identified such as rutin and kampferol rutinoside, the major constituents of the leaves, and N-caffeoyltyramine, lyciumide A, N-dihydrocaffeoyltyramine as well as fatty acids: trihydroxyoctadecadienoic acid and hydroxyoctadecadienoic acid isomers were detected abundantly in the stems. These results showed that the MeOH extracts of stems and leaves of L. arabicum can be considered as a potential source of biological active compounds.

Systematic Review of Chemical Constituents in the Genus Lycium (Solanaceae)

The Lycium genus is widely used as a traditional Chinese medicine and functional food. Many of the chemical constituents of the genus Lycium were reported previously. In this review, in addition to the polysaccharides, we have enumerated 355 chemical constituents and nutrients, including 22 glycerogalactolipids, 29 phenylpropanoids, 10 coumarins, 13 lignans, 32 flavonoids, 37 amides, 72 alkaloids, four anthraquinones, 32 organic acids, 39 terpenoids, 57 sterols, steroids, and their derivatives, five peptides and three other constituents. This comprehensive study could lay the foundation for further research on the Lycium genus.

Feruloyl dopamine-O-hexosides are efficient marker compounds as orthogonal validation for authentication of black cohosh (Actaea racemosa)-an UHPLC-HRAM-MS chemometrics study

Due to the complexity and variation of the chemical constituents in authentic black cohosh (Actaea racemosa) and its potential adulterant species, an accurate and feasible method for black cohosh authentication is not easy. A high-resolution accurate mass (HRAM) LC-MS fingerprinting method combined with chemometric approach was employed to discover new marker compounds. Seven hydroxycinnamic acid amide (HCAA) glycosides are proposed as potential marker compounds for differentiation of black cohosh from related species, including two Asian species (A. foetida, A. dahurica) and two American species (A. pachypoda, A. podocarpa). These markers were putatively identified by comparing their mass spectral fragmentation behavior with those of their authentic aglycone compounds and phytochemistry reports. Two isomers of feruloyl methyldopamine 4-O-hexoside ([M + H]⁺ 506) and one feruloyl tyramine 4-O-hexoside ([M + H]⁺ 476) contributed significantly to the separation of Asian species in principle component analysis (PCA) score plot. The efficacy of the models built on four reasonable combinations of these markers in differentiating black cohosh and its adulterants were evaluated and validated by partial least-square discriminant analysis (PLS-DA). Two models based on these reduced dataset achieved 100% accuracy based on the current sample collection, including the model that used only three feruloyl dopamine-O-hexoside isomers ([M + H]⁺ 492) and one feruloyl dopamine-O-dihexoside ([M + H-hexosyl]⁺ at m/z 492). Graphical abstract Hydroxycinnamic acid amide glycosides are proposed as potential marker compounds for authentication of black cohosh.

Identification and Quantification of Potential Anti-inflammatory Hydroxycinnamic Acid Amides from Wolfberry

Wolfberry or Goji berry, the fruit of Lycium barbarum, exhibits health-promoting properties that leads to an extensive study of their active components. We synthesized a set of hydroxycinnamic acid amide (HCCA) compounds, including trans-caffeic acid, trans-ferulic acid, and 3,4-dihydroxyhydrocinnamic acid, with extended phenolic amine components as standards to identify and quantify the corresponding compounds from wolfberry and to investigate anti-inflammatory properties of these compounds using in vitro model. With optimized LC-MS/MS and NMR analysis, nine amide compounds were identified from the fruits. Seven of these compounds were identified in this plant for the first time. The amide compounds with a tyramine moiety were the most abundant. In vitro studies indicated that five HCCA compounds showed inhibitory effect on NO production inuded by lipopolysaccharides with IC₅₀ less than 15.08 μM (trans-N-feruloyl dopamine). These findings suggested that wolfberries demonstrated anti-inflammatory properties.

Simultaneous Qualitation and Quantitation of Chlorogenic Acids in Kuding Tea Using Ultra-High-Performance Liquid Chromatography-Diode Array Detection Coupled with Linear Ion Trap-Orbitrap Mass Spectrometer

Kuding tea, the leaves of Ilex Kudingcha C.J. Tseng, has been applied for treating obesity, hypertension, cardiovascular disease, hyperlipidemia, and so on. The chlorogenic acids (CGAs) in Kuding tea have shown excellent antioxidative, antiobesity, anti-atherosclerotic and anticancer activities. Nevertheless, the chemical profiles of CGAs in Kuding tea have not been comprehensively studied yet, which hinders further quality control. In the present study, a sensitive ultra-high-performance liquid chromatography-diode array detection coupled with a linear ion trap-Orbitrap (UHPLC-DAD-LTQ-Orbitrap) method was established to screen and identify CGAs in Kuding tea. Six CGA standards were first analyzed in negative ion mode with a CID-MS/MS experiment and then the diagnostic product ions (DPIs) were summarized. According to the retention behavior in the RP-ODS column, accurate mass measurement, DPIs and relevant bibliography data, a total of 68 CGA candidates attributed to 12 categories were unambiguously or preliminarily screened and characterized within 18 min of chromatographic time. This was the first systematic report on the distribution of CGAs in Kuding tea. Meanwhile, the contents of 6 major CGAs in Kuding tea were also determined by the UHPLC-DAD method. All the results indicated that the established analytical method could be employed as an effective technique for the comprehensive and systematic characterization of CGAs and quality control of the botanic extracts or Chinese medicinal formulas that contain various CGAs.

Selective and comprehensive characterization of the quinochalcone C-glycoside homologs in Carthamus tinctorius L. by offline comprehensive two-dimensional liquid chromatography/LTQ-Orbitrap MS coupled with versatile data mining strategies

An offline 2D LC/LTQ-Orbitrap MS approach and versatile data mining techniques were developed to characterize new QCGs from C. tinctorius.

A strategy for establishment of practical identification methods for Chinese patent medicine from systematic multi-component characterization to selective ion monitoring of chemical markers: Shuxiong tablet as a case study

A SMC-SIM strategy for establishment of practical identification methods for Chinese patent medicine.

Serum protein profiles of patients with lung cancer of different histological types

AIMS

To compare serum protein expression profiles between lung cancer patients and healthy individuals, and to examine whether there are differences in serum protein expression profiles among patients with lung cancers of different histological types and whether the characteristic expression of serum proteins may assist in differential diagnosis of various subtypes of lung cancers.

METHODS

Blood samples were collected from 123 lung cancer patients before commencement of treatment who attended Shanxi Cancer Hospital, China, between 2008 and 2013. Blood samples from 60 healthy individuals were also collected in the same period. Serum protein expression profiles were analyzed using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. The differences in the serum protein spectrums of lung cancer patients with different histological subtypes were analyzed by one-way Analysis of Variance and receiver operating characteristic curves.

RESULTS

A cluster of 48 protein mass-to-change ratio (M/Z) peaks was differentially expressed between sera of lung cancer patients and healthy individuals. The M/Z 1205, 4673, 1429 and 4279 peaks were differentially expressed among patients with lung squamous cell carcinomas, adenocarcinomas and small-cell lung carcinomas.

CONCLUSION

These results reinforce the notion that profiling of serum proteins may be of diagnostic value in lung cancer, and suggest that the differences in serum protein profiles may be useful in differential diagnosis of lung cancers of varying histological subtypes.

An integrated strategy for the systematic characterization and discovery of new indole alkaloids from Uncaria rhynchophylla by UHPLC/DAD/LTQ-Orbitrap-MS

The exploration of new chemical entities from herbal medicines may provide candidates for the in silico screening of drug leads. However, this significant work is hindered by the presence of multiple classes of plant metabolites and many re-discovered structures. This study presents an integrated strategy that uses ultrahigh-performance liquid chromatography/linear ion-trap quadrupole/Orbitrap mass spectrometry (UHPLC/LTQ-Orbitrap-MS) coupled with in-house library data for the systematic characterization and discovery of new potentially bioactive molecules. Exploration of the indole alkaloids from Uncaria rhynchophylla (UR) is presented as a model study. Initially, the primary characterization of alkaloids was achieved using mass defect filtering and neutral loss filtering. Subsequently, phytochemical isolation obtained 14 alkaloid compounds as reference standards, including a new one identified as 16,17-dihydro-O-demethylhirsuteine by NMR analyses. The direct-infusion fragmentation behaviors of these isolated alkaloids were studied to provide diagnostic structural information facilitating the rapid differentiation and characterization of four different alkaloid subtypes. Ultimately, after combining the experimental results with a survey of an in-house library containing 129 alkaloids isolated from the Uncaria genus, a total of 92 alkaloids (60 free alkaloids and 32 alkaloid O-glycosides) were identified or tentatively characterized, 56 of which are potential new alkaloids for the Uncaria genus. Hydroxylation on ring A, broad variations in the C-15 side chain, new N-oxides, and numerous O-glycosides, represent the novel features of the newly discovered indole alkaloid structures. These results greatly expand our knowledge of UR chemistry and are useful for the computational screening of potentially bioactive molecules from indole alkaloids. Graphical Abstract A four-step integrated strategy for the systematic characterization and efficient discovery of new indole alkaloids from Uncaria rhynchophylla.

Ultrafiltration coupled with high-performance liquid chromatography and quadrupole-time-of-flight mass spectrometry for screening lipase binders from different extracts of Dendrobium officinale

Pancreatic lipase plays essential roles in the digestion, transport, and processing of dietary lipids in humans. Inhibition of pancreatic lipase leading to the decrease of lipid absorption may be used for treating obesity. In the present study, a new approach of ultrafiltration coupled with high-performance liquid chromatography and quadrupole-time-of-flight mass spectrometry was established for rapidly detecting lipase binders from different extracts of medicinal plants. Rutin, a model inhibitor of lipase, was selected to optimize the screening conditions, including ion strength, temperature, pH, and incubation time. Meanwhile, the specificity of the approach was investigated by using denatured lipase and inactive compound emodin. The optimal screening conditions were as follows: ion strength 75 mM, temperature 37 °C, pH 7.4, and incubation time 10 min. Furthermore, linearity, accuracy, precision, and matrix effect of the approach were well validated. Finally, lipase binders were screened from different extracts of Dendrobium officinale by applying the established approach and were subsequently subjected to traditional lipase inhibitory assay. Eleven lipase inhibitors were identified, eight of which, namely naringenine, vicenin II, schaftoside, isoschaftoside, isoquercetrin, kaempferol 3-O-β-D-glucopyranoside, vitexin 2″-O-glucoside, and vitexin 2″-O-rhamnoside, were reported for the first time. In addition, docking experiments were performed to determine the preferred binding sites of these new lipase inhibitors.

Characterization and quantitative analysis of phenylpropanoid amides in eggplant (Solanum melongena L.) by high performance liquid chromatography coupled with diode array detection and hybrid ion trap time-of-flight mass spectrometry

Eggplant (Solanum melongena L.) is a famous edible and medicinal plant. Despite being widely cultivated and used, data on certain parts other than the fruit are limited. The present study focused on the qualitative and quantitative analysis of the chemical constituents, particularly phenylpropanoid amides (PAs), in eggplant. The mass fragmentation patterns of PAs were proposed using seven authentic compounds with the assistance of a hybrid ion trap time-of-flight mass spectrometer. Thirty-seven compounds (27 PAs and 10 others) were detected and plausibly assigned in the different parts of eggplant. Afterward, a reliable method based on liquid chromatography coupled with diode array detection was developed, validated, and applied for the simultaneous determination of seven PAs and three caffeoylquinic acids in 17 batches of eggplant roots with satisfactory accuracy, precision, and reproducibility, which could not only provide global chemical insight of eggplant but also offer a reliable tool for quality control.