Chronic inflammation on gingiva-derived mesenchymal stem cells.

The impact of inflammatory response on the biological characteristics of GMSCs has been the subject of studies, with conflicting findings. In order to more fully understand the effects of the localized inflammatory environment, the current study assessed the intensity and differentiating capacity of GMSCs derived from healthy periodontal tissues (H-GMSC) and GMSC derived from inflamed periodontal tissues (I-GMSC) tissues. Cells from every well were taken out and counted using a hemocytometer every three days for a total of 12 days.

Energy resolved mass spectrometry of chlorogenic acids and its application to isomer quantification by direct infusion tandem mass spectrometry.

Introduction: With the advent of high-perfomance liquid chromatography (HPLC)-tandem mass spectrometry (MS) using ion trap mass analysers it is possible to acquire unambigious structural information in particular with respect to aspects of regiochemistry and stereochemistry of organic compounds present in complex mixtures such as coffee extracts. However, HPLC-MS methods are resource extensive, laborious and lacking user friendliness.

Objective: To introduce a simple parameter - the energy threshhold for fragmentation - determined using energy resolved MS and demonstrate its value for the complete structural characterisation and even relative quantification of individual isomeric chlrogenic acids in direct infusion experiments.

LC-MS study of the chemical transformations of hydroxycinnamates during yerba maté (Ilex paraguariensis) tea brewing.

Yerba maté is one of the most popular beverages in South American countries and its consumption is associated with a wide array of health effects. In this study, we used advanced HPLC-ESI-MS and HPLC-ESI-HRMS methods for the identification and characterization of hydroxycinnamates and their derivatives formed during the brewing process of yerba maté. We report on the hydroxylation of the hydroxycinnamates cinnamoyl substituent by conjugate addition of water to form 3-hydroxy-dihydrocinnamic acid derivatives using a series of model compounds, including caffeoylglucoses, dicaffeoylquinic acids, methyl caffeoylquinate and mono caffeoylquinic acids.

Profiling and Quantification of Regioisomeric Caffeoyl Glucoses in Berry Fruits.

On the basis of a recently developed tandem mass spectrometry-based hierarchical scheme for the identification of regioisomeric caffeoyl glucoses, selected berry fruits were profiled for their caffeoyl glucose ester content. Fresh edible berries profiled, including strawberries, raspberries, blueberries, blackberries, red currant, black currant, lingonberries, gooseberries, and juices of elderberries, goji berries, chokeberries, cranberries, açai berries, sea buckthorn berries, Montmorency sour cherries, and pomegranates, were investigated. 1-Caffeoyl glucose was found to be the predominant isomer in the majority of samples, with further profiling revealing the presence of additional hydroxycinnamoyl glucose esters and O-glycosides with p-coumaroyl, feruloyl, and sinapoyl substituents.

Profiling and quantification of regioisomeric caffeoyl glucoses in Solanaceae vegetables.

Based on the recently developed tandem MS based hierarchical scheme for the identification of regioisomeric caffeoyl glucoses, selected vegetables were profiled with respect to their caffeoyl glucose content. The dietary plants profiled were tomato, pepper, chilli and aubergine, all members of the Solanaceae family. 6-O-caffeoyl glucose was found to be the predominant isomer.

Synthesis, Structure, and Tandem Mass Spectrometric Characterization of the Diastereomers of Quinic Acid.

(-)-Quinic acid possess eight possible stereoisomers, which occur both naturally and as products of thermal food processing. In this contribution, we have selectively synthesized four isomers, namely, epi-quinic acid, muco-quinic acid, cis-quinic acid, and scyllo-quinic acid, to develop a tandem LC-MS method identifying all stereoisomeric quinic acids. Four derivatives have been unambiguously characterized by single-crystal X-ray crystallography.

Neuraminidase inhibition of Dietary chlorogenic acids and derivatives - potential antivirals from dietary sources.

Plants rich in chlorogenic acids (CGAs), caffeic acids and their derivatives have been found to exert antiviral effects against influenza virus neuroaminidase. In this study several dietary naturally occurring chlorogenic acids, phenolic acids and derivatives were screened for their inhibitory activity against neuroaminidases (NAs) from C. perfringens, H5N1 and recombinant H5N1 (N-His)-Tag using a fluorometric assay.

Differentiation of prototropic ions in regioisomeric caffeoyl quinic acids by electrospray ion mobility mass spectrometry.

Rationale: A series of dietary important regioisomeric chlorogenic acids were investigated by ion mobility mass spectrometry (IM-MS). The existence of prototropic isomers separated in the drift dimension was observed and investigated further using tandem mass spectrometry (MS/MS) and compared with suitable synthetic analogues.

Methods: Using a quadrupole ion mobility time-of-flight mass spectrometer, the IM-MS and IM-MS/MS spectra of selected chlorogenic acids were recorded in the negative ion mode and compared with synthetic analogues.

Investigation of the photochemical changes of chlorogenic acids induced by ultraviolet light in model systems and in agricultural practice with Stevia rebaudiana cultivation as an example.

Mono- and diacyl chlorogenic acids undergo photochemical trans-cis isomerization under ultraviolet (UV) irradiation. The photochemical equilibrium composition was established for eight selected derivatives. In contrast to all other dicaffeoylquinic acid derivatives, cynarin (1,3-dicaffeoylquinic acid) undergoes a [2 + 2] photochemical cycloaddition reaction, constituting a first example of Schmidt's law in a natural product family.

Identification and characterization of chlorogenic acids, chlorogenic acid glycosides and flavonoids from Lonicera henryi L. (Caprifoliaceae) leaves by LC-MSn.

The chlorogenic acids, chlorogenic acid glycosides and flavonoids of the leaves of Lonicera henryi L. (Caprifoliaceae) were investigated qualitatively by liquid chromatography tandem mass spectrometry. Thirty-one chlorogenic acids and their glycosides were detected and characterized to their regioisomeric level on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra.

Identification and characterisation of phenolics from Ixora coccinea L. (Rubiaceae) by liquid chromatography multi-stage mass spectrometry.

Introduction: Ixora coccinea L. leaves and stem are used in traditional Sudanese and Ayurvedic medicinal systems for the treatment of diarrhoea, fever, headache, skin diseases, eye trouble, wounds, sores and ulcers. Recent studies show that I.

Hierarchical key for the LC-MSn identification of all ten regio- and stereoisomers of caffeoylglucose.

A chromatographic method was developed to separate all 10 regio- and stereoisomers of caffeoylglucose. Following chromatographic separation on reversed phase, the fragmentation behavior of all 10 regio- and stereoisomers of caffeoylglucose has been investigated using LC-MS(n). It is possible to discriminate between each of the isomers based on their characteristic fragment spectra and order of elution, including those for which commercial standards are not available.

Investigation of acyl migration in mono- and dicaffeoylquinic acids under aqueous basic, aqueous acidic, and dry roasting conditions.

Acyl migration in chlorogenic acids describes the process of migration of cinnamoyl moieties from one quinic acid alcohol group to another, thus interconverting chlorogenic acid regioisomers. It therefore constitutes a special case of transesterification reaction. Acyl migration constitutes an important reaction pathway in both coffee roasting and brewing, altering the structure of chlorogenic acid initially present in the green coffee bean.

Identification and characterisation of the phenolics of Ilex glabra L. Gray (Aquifoliaceae) leaves by liquid chromatography tandem mass spectrometry.

The phenolics of the leaves of Ilex glabra L. Gray (Aquifoliaceae) were investigated qualitatively by LC-MS(n). Thirty-two phenolics were detected and characterised on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra.

Identification and characterization of the phenolic glycosides of Lagenaria siceraria Stand. (bottle gourd) fruit by liquid chromatography-tandem mass spectrometry.

Bottle gourd, Lagenaria siceraria Stand. (Cucurbitaceae), fruit is used in folk medicines and for culinary purposes in Asia. The phenolics of bottle gourd fruit were investigated qualitatively by LC-MS(n).

Identification of phenolic compounds in plum fruits (Prunus salicina L. and Prunus domestica L.) by high-performance liquid chromatography/tandem mass spectrometry and characterization of varieties by quantitative phenolic fingerprints.

Plums (Prunus domestica L. and Prunus salicina L.) are edible fruits mostly consumed in America, China, and Europe.

What is under the hump? Mass spectrometry based analysis of complex mixtures in processed food--lessons from the characterisation of black tea thearubigins, coffee melanoidines and caramel.

In this contribution we review our work on the characterisation of processed food. We review novel methods and analysis strategies developed to account for the composition of extraordinarily complex materials such as black tea thearubigins, coffee melanoidines and thermally treated carbohydrates. Our methods are mainly based on modern mass spectrometry and are introduced and critically discussed.

Phenolic promiscuity in the cell nucleus--epigallocatechingallate (EGCG) and theaflavin-3,3'-digallate from green and black tea bind to model cell nuclear structures including histone proteins, double stranded DNA and telomeric quadruplex DNA.

Flavanols from tea have been reported to accumulate in the cell nucleus in considerable concentrations. The nature of this phenomenon, which could provide novel approaches in understanding the well-known beneficial health effects of tea phenols, is investigated in this contribution. The interaction between epigallocatechin gallate (EGCG) from green tea and a selection of theaflavins from black tea with selected cell nuclear structures such as model histone proteins, double stranded DNA and quadruplex DNA was investigated using mass spectrometry, Circular Dichroism spectroscopy and fluorescent assays.

Investigating the chemical changes of chlorogenic acids during coffee brewing: conjugate addition of water to the olefinic moiety of chlorogenic acids and their quinides.

Coffee is one of the most popular and consumed beverages in the world and is associated with a series of benefits for human health. In this study we focus on the reactivity of chlorogenic acids, the most abundant secondary metabolites in coffee, during the coffee brewing process. We report on the hydroxylation of the chlorogenic acid cinnamoyl substituent by conjugate addition of water to form 3-hydroxydihydrocaffeic acid derivatives using a series of model compounds including monocaffeoyl and dicaffeoylquinic acids and quinic acid lactones.

Understanding the fate of chlorogenic acids in coffee roasting using mass spectrometry based targeted and non-targeted analytical strategies.

Coffee is one of mankind's most popular beverages obtained from green coffee beans by roasting. Much effort has been expended towards the chemical characterisation of the components of the roasted coffee bean, frequently termed melanoidines, which are dominated byproducts formed from its most relevant secondary metabolites - chlorogenic acids. However, impeded by a lack of suitable authentic reference standards and analytical techniques sufficiently powerful for providing insight into an extraordinarily complex enigmatic material, unsurprisingly little structural and mechanistic information about the products of coffee roasting is available.

Identification and characterization of proanthocyanidins of 16 members of the Rhododendron genus (Ericaceae) by tandem LC-MS.

The proanthocyanidins of the leaves of 16 taxa of the Rhododendron genus (Ericaceae) [Rhododendron 'Catawbiense Grandiflorum', Rhododendron 'Cunningham's White', Rhododendron smirnowii Trautv., Rhododendron calophytum Franch., Rhododendron dichroanthum ssp.

First diastereoselective synthesis of methyl caffeoyl- and feruloyl-muco-quinates.

We report on a diastereoselective synthesis of six derivatives of caffeoyl- and feruloyl-muco-quinic acids. All the muco-quinic acid derivatives were obtained in excellent yield in five steps starting from quinic acid, caffeic acid and ferulic acid. Allyl ether protection of trans-hydroxy cinnamic acids was here introduced to chlorogenic acids synthesis.

Hill coefficients of dietary polyphenolic enzyme inhibitiors: can beneficial health effects of dietary polyphenols be explained by allosteric enzyme denaturing?

Inspired by a recent article by Prinz, suggesting that Hill coefficients, obtained from four parameter logistic fits to dose-response curves, represent a parameter allowing distinction between a general allosteric denaturing process and real single site enzyme inhibition, Hill coefficients of a number of selected dietary polyphenol enzyme inhibitions were compiled from the available literature. From available literature data, it is apparent that the majority of polyphenol enzyme interactions reported lead to enzyme inhibition via allosteric denaturing rather than single site inhibition as judged by their reported Hill coefficients. The results of these searches are presented and their implications discussed leading to the suggestion of a novel hypothesis for polyphenol biological activity termed the insect swarm hypothesis.

How to distinguish between cinnamoylshikimate esters and chlorogenic acid lactones by liquid chromatography-tandem mass spectrometry.

In this study, liquid chromatography-tandem mass spectrometry (LC-MS(n); n = 2-3) has been used to characterize and distinguish chlorogenic acid lactones from cinnamoylshikimate esters. This is the first time when an LC-MS(n) method has been developed to distinguish between these two isomeric classes of compounds formed in particular in food processing from chlorogenic acids at elevated temperature through loss of water. The structures of regioisomeric chlorogenic acid lactones and shikimate esters have been assigned on the basis of LC-MS(n) patterns of fragmentation, relative hydrophobicity, and fragmentation analogy with the synthetic standards of dimethoxycinnamic, ferulic, and caffeic acid containing monoacyl chlorogenic acid lactones and shikimate esters.

Characterization and quantification of hydroxycinnamate derivatives in Stevia rebaudiana leaves by LC-MSn.

Stevia rebaudiana leaves are used as a zero-calorie natural sweetener in a variety of food products in Asian countries, especially in Japan. In this study, the hydroxycinnamate derivatives of S. rebaudiana have been investigated qualitatively and quantitatively by LC-MSn.