Identification of antioxidant phenolic compounds in feverfew (Tanacetum parthenium) by HPLC-ESI-MS/MS and NMR

Phytochemical Investigation of Polyphenols from the Aerial Parts of Tanacetum balsamita Used in Transylvanian Ethnobotany and Parallel Artificial Membrane Permeability Assay

In this study, based on ethnobotanical data recorded in Transylvania, the polyphenolic compounds and the permeability of the aerial part's extract of Tanacetum balsamita were investigated. Ultrahigh-performance liquid chromatography-tandem mass spectrometry was applied for the analysis of the extracts. Parallel artificial membrane permeability assay (PAMPA) for the gastrointestinal tract and the blood-brain barrier was conducted. In the ethanolic and aqueous extracts of the species traditionally used for wound, furuncle, and liver disorders, 92 polyphenols were characterized (e.g., flavonoid, hydroxycinnamic acid, catechin, dihydroxybenzoyl, lignan derivatives, and a monoterpene) including 54 compounds identified for the first time in the plant. In the PAMPA tests, eight components were shown to be capable of passive diffusion across the studied membranes. These include apigenin and seven methoxylated flavonoid derivatives. Based on these results, methoxylated flavonoids might promote the pharmacological potential of T. balsamita to be applied in the enhancement of novel remedies.

Secondary metabolic profiling, antioxidant potential, enzyme inhibitory activities and in silico and ADME studies: a multifunctional approach to reveal medicinal and industrial potential of Tanacetum falconeri

Tanacetum falconeri is a significant flowering plant that possesses cytotoxic, insecticidal, antibacterial, and phytotoxic properties. Its chemodiversity and bioactivities, however, have not been thoroughly investigated. In this work, several extracts from various parts of T. falconeri were assessed for their chemical profile, antioxidant activity, and potential for enzyme inhibition. The total phenolic contents of T. falconeri varied from 40.28 ± 0.47 mg GAE/g to 11.92 ± 0.22 mg GAE/g in various extracts, while flavonoid contents were found highest in TFFM (36.79 ± 0.36 mg QE/g extract) and lowest (11.08 ± 0.22 mg QE/g extract) in TFSC (chloroform extract of stem) in similar pattern as found in total phenolic contents. Highest DPPH inhibition was observed for TFFC (49.58 ± 0.11 mg TE/g extract) and TFSM (46.33 ± 0.10 mg TE/g extract), whereas, TFSM was also potentially active against (98.95 ± 0.57 mg TE/g) ABTS radical. In addition, TFSM was also most active in metal reducing assays: CUPRAC (151.76 ± 1.59 mg TE/g extract) and FRAP (101.30 ± 0.32 mg TE/g extract). In phosphomolybdenum assay, the highest activity was found for TFFE (1.71 ± 0.03 mg TE/g extract), TFSM (1.64 ± 0.035 mg TE/g extract), TFSH (1.60 ± 0.033 mg TE/g extract) and TFFH (1.58 ± 0.08 mg TE/g extract), while highest metal chelating activity was recorded for TFSH (25.93 ± 0.79 mg EDTAE/g extract), TFSE (22.90 ± 1.12 mg EDTAE/g extract) and TFSC (19.31 ± 0.50 mg EDTAE/g extract). In biological screening, all extracts had stronger inhibitory capacity against AChE while in case of BChE the chloroform extract of flower (TFFC) and stem (TFSC) showed the highest activities with inhibitory values of 2.57 ± 0.24 and 2.10 ± 0.18 respectively. Similarly, TFFC and TFSC had stronger inhibitory capacity (1.09 ± 0.015 and 1.08 ± 0.002 mmol ACAE/g extract) against α-Amylase and (0.50 ± 0.02 and 0.55 ± 0.02 mmol ACAE/g extract) α-Glucosidase. UHPLC-MS study of methanolic extract revealed the presence of 133 components including sterols, triterpenes, flavonoids, alkaloids, and coumarins. The total phenolic contents were substantially linked with all antioxidant assays in multivariate analysis. These findings were validated by docking investigations, which revealed that the selected compounds exhibited high binding free energy with the enzymes tested. Finally, it was found that T. falconeri is a viable industrial crop with potential use in the production of functional goods and nutraceuticals.

Overview of Ethnobotanical-Pharmacological Studies Carried Out on Medicinal Plants from the Serra da Estrela Natural Park: Focus on Their Antidiabetic Potential

The Serra da Estrela Natural Park (NPSE) in Portugal stands out as a well-preserved region abundant in medicinal plants, particularly known for their pharmaceutical applications in diabetes prevention and treatment. This comprehensive review explores these plants' botanical diversity, traditional uses, pharmacological applications, and chemical composition. The NPSE boast a rich diversity with 138 medicinal plants across 55 families identified as traditionally and pharmacologically used against diabetes globally. Notably, the Asteraceae and Lamiaceae families are prevalent in antidiabetic applications. In vitro studies have revealed their significant inhibition of carbohydrate-metabolizing enzymes, and certain plant co-products regulate genes involved in carbohydrate metabolism and insulin secretion. In vivo trials have demonstrated antidiabetic effects, including glycaemia regulation, insulin secretion, antioxidant activity, and lipid profile modulation. Medicinal plants in NPSE exhibit various activities beyond antidiabetic, such as antioxidant, anti-inflammatory, antibacterial, anti-cancer, and more. Chemical analyses have identified over fifty compounds like phenolic acids, flavonoids, terpenoids, and polysaccharides responsible for their efficacy against diabetes. These findings underscore the potential of NPSE medicinal plants as antidiabetic candidates, urging further research to develop effective plant-based antidiabetic drugs, beverages, and supplements.

Impact of Heavy Metal Pollution in the Environment on the Metabolic Profile of Medicinal Plants and Their Therapeutic Potential

The paper provides a comprehensive examination of heavy metal stress on medicinal plants, focusing on its impact on antioxidant capacity and biosynthetic pathways critical to their therapeutic potential. It explores the complex relationship between heavy metals and the physiological and biochemical responses of medicinal plants, highlighting how metal stress disrupts biosynthetic pathways, altering concentrations of secondary metabolites. This disruption may compromise the overall quality and efficacy of medicinal plants, requiring a holistic understanding of its cumulative impacts. Furthermore, the study discusses the potential of targeted genetic editing to enhance plant resilience against heavy metal stress by manipulating genes associated with antioxidant defenses. This approach represents a promising frontier in safeguarding medicinal plants in metal-contaminated environments. Additionally, the research investigates the role of phytohormone signaling in plant adaptive mechanisms to heavy metal stress, revealing its influence on biochemical and physiological responses, thereby adding complexity to plant adaptation. The study underscores the importance of innovative technologies and global cooperation in protecting medicinal plants' therapeutic potential and highlights the need for mitigation strategies to address heavy metal contamination effectively.

Application of High-Performance Liquid Chromatography with Diode Array Detection to Simultaneous Analysis of Reference Antioxidants and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) in Free Radical Scavenging Test

Antioxidant activity can be analyzed by various methods, both in vitro and in vivo. The widely used colorimetric method using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging reaction has many limitations, such as interference from photosynthetic pigments naturally found in plant extracts. The DPPH-HPLC eliminates these troubles by enabling the separation of the DPPH free radical (DPPH-R) peak and its reduced form (DPPH-H) from other extract components. However, simultaneous analysis of antioxidants and evaluation of their activity is more complicated. To date, a post-column reaction with DPPH has been used for this purpose. The aim of the current study was the elaboration on a DPPH-RP-HPLC in gradient elution mode for simultaneous evaluation of the antioxidant activity of standards on the basis of DPPH-R peak inhibition, together with the identification of standards, as well as the products of redox reactions. The following antioxidants (AOs) were used as standards: quercetin, resveratrol, Trolox, chlorogenic acid, hesperetin, and coumarin. Flavone was used as the control chemical without antioxidant activity. The separation of the DPPH-R/DPPH-H pair, together with standards and reaction products, was studied on a C18 column using a gradient of acetonitrile from 5 to 60% within 20 min. The stability of DPPH was evaluated with different gradient profiles. The influence of the addition of acetic acid in concentrations of 0.05 to 1%, the duration of the analysis, and the radiation emitted by the UV lamp of a diode array detector on the induction of DPPH decomposition processes were investigated. The most significant parameter affecting DPPH stability appeared to be the acidic environment and water content in the mobile phase. An increase in the water content from 70 to 95% worsened the LOD of DPPH-R from 31.64 nM to 107.31 nM, as measured at 517 nm, and from 189.41 to 1677.05 nM at 330 nm. Each gradient profile provided good linearity (R² = 0.9790–0.9977) of the relationship between the DPPH-R as well as DPPH-H peak areas, and a wide concentration range from 0.5 to 2.5 mM for UV-vis detection. Free radical scavenging activity was expressed by the percentage of DPPH-R peak inhibition at 517 nm. This simple method is suitable for monitoring DPPH radical scavenging by AO standards.

Phytochemical profile of Centevita®, a Centella asiatica leaves extract, and isolation of a new oleanane-type saponin

Centella asiatica is a popular medicinal plant and several phytotherapic products in the market include its extracts as active constituents. A LC-MS guided phytochemical investigation on the commercial C. asiatica leaves extract named Centevita® allowed characterization and quantification of 24 secondary metabolites including 10 polyphenols and 14 ursane- or oleanane-type triterpenoids in the sapogenin or saponin form. This metabolomic analysis, besides confirming that the triterpenoid fraction roughly accounts for 45% of the extract weight, also resulted in the discovery of isoterminoloside, a new triglycoside saponin of the unprecedented 2α,3β,6β,23-tetrahydroxyolean-13(18)-en-28-oic acid (isoterminolic acid). The structure of isoterminoloside was characterized by a detailed ESI-MS and NMR investigation.

The Association of Tanacetum parthenium and Salix alba Extracts Reduces Cortex Serotonin Turnover, in an Ex Vivo Experimental Model of Migraine

The mixture of water extracts from Tanacetum parthenium and Salix alba was studied in an ex vivo assessment of neurotoxicity constituted by isolated mouse cortex specimens challenged with K+ 60 mM Krebs–Ringer buffer (neurotoxicity stimulus). The effects of the mixture on lactate dehydrogenase (LDH), nitrite and serotonin levels were investigated. The phytochemical profile of the mixture was also evaluated. A docking approach was conducted to predict, albeit partially, the putative mechanism underlying the observed effects. The extracts displayed a good profile of polyphenolic compounds (22 chromatographic peaks detected), with caftaric acid and epicatechin being the prominent phenols. In isolated cortex, the association of T. parthenium and S. alba extracts was effective in reducing the K+ 60 mM-induced levels of LDH and nitrites, whereas the neurotoxicity stimulus-induced serotonin depletion was prevented by the treatment. Regarding the inhibition of serotonin catabolism, epicatechin (44.65 µg/mg) and caftaric acid (10.51 µg/mg) were putatively the main compounds involved in the inhibition of monoamineoxidase-A, which is known to play a master role in serotonin turnover. Collectively, the results of the present study point to the efficacy of the present extract mixture as an innovative pharmacological tool to prevent the onset of migraine.

Density-functional theory of the catnip molecule, nepetalactone

Nepetalactones belongs to the group of iridoid monoterpenoids, which are present in the aerial parts of nepeta plants. Nepetalactone is an attractant to feline animals causing euphoric effects, while it is a repellent to mosquitoes and cockroaches. It is also a pheromone for several insect aphid species. The main objective of this research was to study the electronic and spectral properties of nepetalactones. We investigated its structural properties using hybrid density-functional theory of B3LYP and WB97XD functional with the 6-311++G(d,p) basis set to optimize the geometry, and then computed the electronic structure, HOMO-LUMO, natural bond orbitals, molecular electronic potential and its contour map. We also obtained spectral signatures of NMR, IR and UV-Vis, and compared them with experimental data from the literature. The DFT study provided different electronic and spectral information that will be of value for further research on making new derivatives of nepetalactones for commercial purposes. Nepetalactones have a promising future in the development of novel mosquito repellents for the control of malaria and arboviral diseases.

Jasmonates promote enhanced production of bioactive caffeoylquinic acid derivative in Eclipta prostrata (L.) L. hairy roots

Eclipta prostrata (L.) L. is widely used in traditional medicine for treatment of hepatitis, poisoning from snake bites and viral infections. Pharmacological studies confirmed its antioxidant, anti-inflammatory and anticancer activities. The efficacy of E. prostrata (L.) L. extracts has been correlated to phenylpropanoids such as flavonoids, coumestans and caffeoylquinic acid derivatives. In this work, the production of wedelolactone, demethylwedelolactone and 3,5-di-O-caffeoylquinic acid (3,5-diCQA) in hairy root cultures of E. prostrata (L.) L. C19 clone was increased after addition of eliciting agents jasmonic acid (JA) or methyl jasmonate (MeJA) at multiple concentrations. Cultures elicited with 100 μM of JA saw a 5.2 fold increase in wedelolactone (from 0.72 to 3.72 mg/g d.w.), a 1.6 fold increase in demethylwedelolactone (from 5.54 to 9.04 mg/g d.w.) and a 2.47 fold increase in 3,5-diCQA (from 18.08 to 44.71 mg/g d.w.). Obtained data validate the potential of E. prostrata (L.) L. hairy root cultures as a production system of wedelolactone, demethylwedelolactone and especially 3,5-diCQA, which has recently been reported to possess activity against coronavirus disease (Covid-19) by in silico computational studies.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11240-021-02201-4.

Application of Phytotests to Study of Environmental Safety of Biologicaly Synthetised Au and Au/ZnO Nanoparticles Using Tanacetum parthenium Extract

Due to their small sizes and high reactivity, nanoparticles have a completely different toxicity profile than larger particles, and it is difficult to predict their potential ecological impact. There is a need for broad ecotoxicological studies of nanomaterials in order to specify their environmental impact and ensure safe application of nanotechnology products. In this work, we have assessed the toxicity of Au and Au/ZnO metal nanoparticles obtained with the use of Tanacetum parthenium (herba) extract. The obtained nanoparticles were characterized by UV–Vis spectrophotometry (UV–VIS), Transmission electron microscopy (TEM), Atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR). In order to assess the toxicity of biologically synthesized nanoparticles, we used seeds of various plants: Lepidium sativum, Linum flavum, Zea mays, Salvia hispanica-chia, Lupinus angustifolius, Petroselinum crispum subsp. Crispum, Beta vulgaris, Phaseolus vulgaris. The in vitro phytotests showed that gold nanoparticles at a specific range of concentrations for all plants stimulated their growth. The highest growth activity was exhibited by the solution at the concentration of 0.300 mg/ml towards corn (Aw ≈ − 135 ± 16) and flax (Aw ≈ − 44 ± 10). Only for parsley the IC50 was determined at 0.57 mg/ml, but solutions at the concentration of 0.030 to 0.150 mg/ml also stimulated plant growth. Au/ZnO had a toxic effect at all concentrations applied in the study.

Absorption Coefficients of Phenolic Structures in Different Solvents Routinely Used for Experiments

Phenolic structures are of great interest due to their antioxidant properties and various postulated benefits on human health. However, the quantification of these structures in fruits and vegetables, as well as in vivo or in vitro experiments, is demanding, as relevant concentrations are often low, causing problems in exactly weighing the respective amounts. Nevertheless, the determination of used concentrations is often a prerequisite for accurate results. A possibility to quantify polyphenol is the use of UV/vis spectroscopy. Therefore, the absorption coefficients of selected phenolic structures were determined in three different solvents relevant for polyphenol research (water/methanol (50/50, v/v), water, and phosphate buffer at pH 7.5). To confirm the values based on weight and to avoid errors due to impurities, hygroscopic effects, and inadequate balance care, the mass concentrations were additionally determined by quantitative NMR (q-NMR). The coefficients presented in this article can help to quickly and easily determine accurate concentrations in a laboratory routine without wasting the often-precious standard compounds.

Antioxidants: Classification, Natural Sources, Activity/Capacity Measurements, and Usefulness for the Synthesis of Nanoparticles

Natural extracts are the source of many antioxidant substances. They have proven useful not only as supplements preventing diseases caused by oxidative stress and food additives preventing oxidation but also as system components for the production of metallic nanoparticles by the so-called green synthesis. This is important given the drastically increased demand for nanomaterials in biomedical fields. The source of ecological technology for producing nanoparticles can be plants or microorganisms (yeast, algae, cyanobacteria, fungi, and bacteria). This review presents recently published research on the green synthesis of nanoparticles. The conditions of biosynthesis and possible mechanisms of nanoparticle formation with the participation of bacteria are presented. The potential of natural extracts for biogenic synthesis depends on the content of reducing substances. The assessment of the antioxidant activity of extracts as multicomponent mixtures is still a challenge for analytical chemistry. There is still no universal test for measuring total antioxidant capacity (TAC). There are many in vitro chemical tests that quantify the antioxidant scavenging activity of free radicals and their ability to chelate metals and that reduce free radical damage. This paper presents the classification of antioxidants and non-enzymatic methods of testing antioxidant capacity in vitro, with particular emphasis on methods based on nanoparticles. Examples of recent studies on the antioxidant activity of natural extracts obtained from different species such as plants, fungi, bacteria, algae, lichens, actinomycetes were collected, giving evaluation methods, reference antioxidants, and details on the preparation of extracts.

Bioactive Compounds from Leaves and Twigs of Guayule Grown in a Mediterranean Environment

Guayule (Parthenium argentatum) is one of the most promising alternatives to produce natural rubber. As the guayule leaves represent a waste byproduct in the rubber extraction process, their exploitation might contribute to the valorization of the whole plant biomass. The specific aim of our study was to determine the antioxidant capacity and the content of phenolic compounds in leaves and twigs of different guayule lines cultivated in a Mediterranean environment. The antioxidant capacity and the contents of phenolic were affected significantly by guayule accession and harvest time. Overall means in twigs represented about 60% of the corresponding leaf values for antioxidant capacity as DPPH (1,1-diphenyl-2-picrylhydrazyl) and not tannic phenolic and about 55% as ABTS (2,2′-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt), total phenolic, tannic phenolic and total flavonoid contents. Five individual phenolic compounds were identified in methanolic extracts of leaves. Neochlorogenic acid (62.5–174.8 mg g⁻¹ DW) and chlorogenic acid (28.6–41.1 mg g⁻¹ DW) were the most abundant phenolic acids. In addition to the compounds quantified in leaves, cynarin was identified only in twigs and for the first time in guayule biomass. Our results indicate that guayule leaves and twigs represent a rich source of antioxidants for potential applications in fodder, nutraceutical and pharmacological sectors.

The strengths and weaknesses of NMR spectroscopy and mass spectrometry with particular focus on metabolomics research

Mass spectrometry (MS) and nuclear magnetic resonance (NMR) have evolved as the most common techniques in metabolomics studies, and each brings its own advantages and limitations. Unlike MS spectrometry, NMR spectroscopy is quantitative and does not require extra steps for sample preparation, such as separation or derivatization. Although the sensitivity of NMR spectroscopy has increased enormously and improvements continue to emerge steadily, this remains a weak point for NMR compared with MS. MS-based metabolomics provides an excellent approach that can offer a combined sensitivity and selectivity platform for metabolomics research. Moreover, different MS approaches such as different ionization techniques and mass analyzer technology can be used in order to increase the number of metabolites that can be detected. In this chapter, the advantages, limitations, strengths, and weaknesses of NMR and MS as tools applicable to metabolomics research are highlighted.

NMR Studies of Hetero-Association of Caffeine with di-O-Caffeoylquinic Acid Isomers in Aqueous Solution

Caffeine hetero-association with 3,5-di-O-caffeoylquinic acid, 3,4-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid in aqueous solution has been investigated by one-dimensional (1D) and two-dimensional (2D) high resolution ¹H and ¹³C NMR spectroscopy. Self-association of the di-O-caffeoylquinic acid isomers has been studied as well. Caffeine-di-O-caffeoylquinic acid isomers association constants were measured. The value of the association constant of the caffeine-di-O-caffeoylquinic acid complexes is compatible with previous studies and within the typical range of reported association constants for other caffeine-polyphenols complexes. Structural features of the three different complexes have also been investigated by NMR spectroscopy combined with quantum chemical calculations, and the complex conformation is discussed. Our results show that stacking interactions drive the formation of the complexes and that multiple equilibria are present in the interaction of caffeine with 3,4-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid while the complex with 3,5-di-O-caffeoylquinic acid seems to be better defined.

Genesis and development of DPPH method of antioxidant assay

α, α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging method offers the first approach for evaluating the antioxidant potential of a compound, an extract or other biological sources. This is the simplest method, wherein the prospective compound or extract is mixed with DPPH solution and absorbance is recorded after a defined period. However, with the advancement and sophistication in instrumental techniques, the method has undergone various modifications to suit the requirements, even though the basic approach remains same in all of them. This article presents a critical review on various developments to the DPPH method.

Determination of the hydroxycinnamate profile of 12 members of the Asteraceae family

The hydroxycinnamates of the leaves of 12 plants of the Astreraceae family, Achillea millefolium, Arnica montana, Artemesia dracunculus, Cichorium intybus, Cnicus benedictus, Cynara scolymus, Echinops humilis, Inula helenium, Lactuca sativa, Petasites hybridus, Solidago virgaurea, and Tanacetum parthenium were investigated qualitatively by LC-MS(n). Thirty-nine chlorogenic acids were detected and all characterized to regioisomeric level on the basis of their fragmentation pattern in the tandem MS spectra, most of them for the first time from these sources with two of them previously not reported in nature. Both chlorogenic acids based on trans and cis-cinnamic acid substituents were identified. Assignment to the level of individual regioisomers was possible for seven caffeoylquinic acids (1-7), 11 dicaffeoylquinic acids (17-27), six feruloylquinic acids (9-14), two p-coumaroylquinic acids (15-16), two caffeoyl-feruloylquinic acids (28 and 29), four caffeoyl-p-coumaroylquinic acids (30-33), three dicaffeoyl-succinoylquinic acids (34-36), two dicaffeoyl-methoxyoxaloylquinic acids (37 and 38), and one tricaffeoylquinic acid (39). Furthermore, one caffeoylshikimic acid (40), one caffeoyltartaric acid (41), three dicaffeoyltartaric acids (42-44), and three caffeoyl-feruloyltartaric acids (45-47) were detected and shown to possess characteristic tandem MS spectra and were tentatively assigned on the basis of their retention time and previously developed hierarchical keys.

Recent advances on HPLC/MS in medicinal plant analysis

With gaining popularity of herbal remedies worldwide, the need of assuring safety and efficacy of these products increases as well. By nature they are complex matrices, comprising a multitude of compounds, which are prone to variation due to environmental factors and manufacturing conditions. Furthermore, many traditional preparations compose of multiple herbs, so that only highly selective, sensitive and versatile analytical techniques will be suitable for quality control purposes. By hyphenating high performance liquid chromatography and mass spectrometry (LC-MS) these high demands are fulfilled, providing the user with a multitude of technical options and applications. This review intends to reflect the impact of LC-MS for medicinal plant analysis focusing on most relevant reports published within the last five years. Commenced by introductory remarks to the different MS approaches most commonly used (e.g. ion trap and time of flight mass analyzers, fragmentation and ionization modes), respective LC-MS applications on the analysis of natural products in medicinal plants, commercial products and biological samples are presented. Methodological aspects like stationary and mobile phase selection or MS settings are discussed, and advantages or limitations of the described techniques are highlighted.

Antioxidant Principles of Tanacetum vulgare L. Aerial Parts

The methanolic extract of aerial parts of Tanacetum vulgare L. (Asteraceae) and its fractions were investigated for antioxidant activity. The crude extract displayed DPPH radical scavenging effects with an EC50 value of 37 ± 1.2 μg/mL (n=3). Activity-guided fractionations of the crude extract resulted in the isolation of three antioxidant compounds; 3,5-O-dicaffeoylquinic acid (3,5-DCQA), axillarin and luteolin. 3,5-DCQA was the major constituent with antioxidant activity (IC50 = 9.7 μM) comparable with that of the standard quercetin (IC50 = 8.8 μM). Though the isolated compounds were previously known for their antioxidant effects, this is the first report on the identification of 3,5-DCQA from Tanacetum vulgare. The displayed potent antioxidant activity of the crude extract and isolated active principles is in support of the traditional medicinal uses of the plant for disease conditions such as wound healing, rheumatic arthritis and other inflammatory conditions.

Analysis of caffeic acid derivatives from Osmanthus yunnanensis using electrospray ionization quadrupole time-of-flight mass spectrometry

A series of six caffeic acid derivatives (1-6) in Osmanthus yunnanensis were investigated by electrospray quadrupole time-of-flight tandem mass spectrometry (ESI-QToF-MS/MS) in both negative- and positive-ion modes. High-quality MS/MS spectra of [M + H](+) are generated from high-abundance protonated parent ions obtained by addition of ammonium chloride to the solutions. Fragmentation mechanisms of [M - H](-) and [M + H](+) precursor ions were proposed and elemental compositions of most of the product ions were confirmed on the basis of the high-resolution ESI-collision-induced dissociation (CID)- MS/MS spectra. It was found that the fragment ions at m/z 179, m/z 161, m/z 135 and m/z 134 in negative-ion mode and at m/z 163, m/z 145 and m/z 135 in positive mode should be the characteristic ions of caffeic acid. In addition, the radical fragment ions with high abundance were observed for many caffeic acid derivatives especially for 4. The structural elements of unknown compounds 7 and 8 were tentatively identified on based on tandem mass spectra of known ones.

Complete Characterization of Extracts of Onopordum illyricum L. (Asteraceae) by HPLC/PDA/ESIMS and NMR

The aerial parts of Onopordum illyricum L. (Asteraceae) are eaten raw in salad in the Mediterranean area, representing a food of good nutritional value. Extracts of different parts of this plant have been analyzed by HPLC/DAD/ESIMS and the major compounds identified by NMR spectroscopy. Fatty acids, sesquiterpene lactones, triterpenes and polyphenols (flavones and caffeoyl quinic acids) fully describe the plant metabolism during the vegetation year. All the metabolites are non toxic nutrients, and are reported in the literature to possess biological activities positive for health, confirming the beneficial use in the diet of this thistle