List of works - Nikolai Kuhnert

A systematic study of carboxylic acids in negative ion mode electrospray ionisation mass spectrometry providing a structural model for ion suppression

article

Absolute bioavailability and dose-dependent pharmacokinetic behaviour of dietary doses of the chemopreventive isothiocyanate sulforaphane in rat

scientific article published on 10 September 2007

Analysis of minor low molecular weight carbohydrates in cocoa beans by chromatographic techniques coupled to mass spectrometry

scientific article published on 19 November 2018

Aseptic artificial fermentation of cocoa beans can be fashioned to replicate the peptide profile of commercial cocoa bean fermentations

scientific article published on 12 October 2016

Bioactivity in Rhododendron: A Systemic Analysis of Antimicrobial and Cytotoxic Activities and Their Phylogenetic and Phytochemical Origins

scientific article published on 13 April 2017

Biochemical fate of vicilin storage protein during fermentation and drying of cocoa beans.

scientific article published on 26 October 2016

Changes in low molecular weight carbohydrates in kale during development and acclimation to cold temperatures determined by chromatographic techniques coupled to mass spectrometry

scientific article published on 08 October 2019

Characterisation of "caramel-type" thermal decomposition products of selected monosaccharides including fructose, mannose, galactose, arabinose and ribose by advanced electrospray ionization mass spectrometry methods

scientific article published on 25 March 2013

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

scientific article published on 31 August 2011

Characterization by LC-MS(n) of four new classes of chlorogenic acids in green coffee beans: dimethoxycinnamoylquinic acids, diferuloylquinic acids, caffeoyl-dimethoxycinnamoylquinic acids, and feruloyl-dimethoxycinnamoylquinic acids

scientific article published in March 2006

Characterization by LC-MS(n) of four new classes of p-coumaric acid-containing diacyl chlorogenic acids in green coffee beans

scientific article published in June 2006

Characterization of commercial green tea leaves by the analysis of low molecular weight carbohydrates and other quality indicators

scientific article published on 15 March 2019

Characterization of triacylglycerols in unfermented cocoa beans by HPLC-ESI mass spectrometry

scientific article published on 02 February 2018

Chemistry inside molecular containers in the gas phase

scientific article published on 7 April 2013

Comparison and quantification of chlorogenic acids for differentiation of green Robusta and Arabica coffee beans

scientific article published on 02 September 2019

Comparison of the polyphenolic profile and antibacterial activity of the leaves, fruits and flowers of Rhododendron ambiguum and Rhododendron cinnabarinum.

scientific article published on 20 July 2017

Degradation of cocoa proteins into oligopeptides during spontaneous fermentation of cocoa beans

scientific article published on 01 May 2018

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

scientific article published on 30 March 2011

Differentiation of black tea infusions according to origin, processing and botanical varieties using multivariate statistical analysis of LC-MS data

scientific article published on 26 March 2018

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

scientific article published in April 2015

Discriminating between the six isomers of dicaffeoylquinic acid by LC-MS(n).

scientific article published in May 2005

Diversity of Kale (Brassica oleracea var. sabellica): Glucosinolate Content and Phylogenetic Relationships.

scientific article

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

scientific article published on 21 May 2018

Experimentally modelling cocoa bean fermentation reveals key factors and their influences

scientific article published on 08 August 2019

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

scientific article published on 07 June 2012

Fourier transform ion cyclotron resonance mass spectrometrical analysis of raw fermented cocoa beans of Cameroon and Ivory Coast origin

scientific article published on 01 August 2014

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

scientific article

Hierarchical scheme for LC-MSn identification of chlorogenic acids

scientific article (publication date: 7 May 2003)

Hierarchical scheme for liquid chromatography/multi-stage spectrometric identification of 3,4,5-triacyl chlorogenic acids in green Robusta coffee beans

scientific article published on August 2010

High molecular weight non-polar hydrocarbons as pure model substances and in motor oil samples can be ionized without fragmentation by atmospheric pressure chemical ionization mass spectrometry

scientific article

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

scientific article published on January 29, 2011

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

scientific article published on 01 September 2011

How to distinguish between feruloyl quinic acids and isoferuloyl quinic acids by liquid chromatography/tandem mass spectrometry

scientific article published in June 2010

How to identify and discriminate between the methyl quinates of chlorogenic acids by liquid chromatography-tandem mass spectrometry

scientific article published on 01 March 2011

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

scientific article published on 4 September 2014

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

scientific article published on 30 July 2014

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

scientific article published on 15 September 2014

Identification and characterization of five new classes of chlorogenic acids in burdock (Arctium lappa L.) roots by liquid chromatography/tandem mass spectrometry

scientific article published on 6 December 2010

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

scientific article published in April 2012

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

scientific article

Identification and characterization of two new derivatives of chlorogenic acids in Arnica (Arnica montana L.) flowers by high-performance liquid chromatography/tandem mass spectrometry

scientific article published on 31 March 2011

Identification of Products from Thermal Degradation of Tryptophan Containing Pentapeptides: Oxidation and Decarboxylation

scientific article published on 25 June 2019

Identification of novel homologous series of polyhydroxylated theasinensins and theanaphthoquinones in the SII fraction of black tea thearubigins using ESI/HPLC tandem mass spectrometry

scientific article published on 29 September 2014

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

scientific article published on 2 December 2013

Investigating the Thermal Decomposition of Starch and Cellulose in Model Systems and Toasted Bread Using Domino Tandem Mass Spectrometry ⬇️

scientific article published on January 11, 2013

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

scientific article published on 29 November 2012

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

scientific article published on 8 September 2014

Investigation of isomeric flavanol structures in black tea thearubigins using ultraperformance liquid chromatography coupled to hybrid quadrupole/ion mobility/time of flight mass spectrometry

scientific article published on November 2014

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.

scientific article published on 30 March 2015

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

scientific article

MALDI-TOF Mass Spectrometry: Avoidance of Artifacts and Analysis of Caffeine-Precipitated SII Thearubigins from 15 Commercial Black Teas ⬇️

scientific article published on April 27, 2012

Mass spectrometric characterization of black tea thearubigins leading to an oxidative cascade hypothesis for thearubigin formation ⬇️

scientific article published on December 15, 2010

Metabolome Comparison of Bioactive and Inactive Rhododendron Extracts and Identification of an Antibacterial Cannabinoid(s) from Rhododendron collettianum.

scientific article published on 13 June 2017

Model system-based mechanistic studies of black tea thearubigin formation

scientific article published on 12 February 2015

Modulation of hepatic cytochromes P450 and phase II enzymes by dietary doses of sulforaphane in rats: Implications for its chemopreventive activity

scientific article published in November 2005

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

scientific article

On the activation of valerolactam with triflic anhydride: the synthesis of omega-trifluorosulfonamido dipeptides using a transpeptidation reaction under mild conditions

scientific article published on 29 March 2005

One size does not fit all--bacterial cell death by antibiotics cannot be explained by the action of reactive oxygen species

scientific article published on 3 September 2013

Origin and varietal based proteomic and peptidomic fingerprinting of Theobroma cacao in non-fermented and fermented cocoa beans

scientific article published on 16 May 2018

Origin-based polyphenolic fingerprinting of Theobroma cacao in unfermented and fermented beans.

scientific article published on 03 June 2017

Oxidative cascade reactions yielding polyhydroxy-theaflavins and theacitrins in the formation of black tea thearubigins: Evidence by tandem LC-MS ⬇️

scientific article published on October 14, 2010

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.

scientific article published in February 2013

Probing the dynamic reversibility and generation of dynamic combinatorial libraries in the presence of bacterial model oligopeptides as templating guests of tetra-carbohydrazide macrocycles using electrospray mass spectrometry.

scientific article

Probing the mechanism and dynamic reversibility of trianglimine formation using real‐time electrospray ionization time‐of‐flight mass spectrometry ⬇️

scientific article published on May 15, 2012

Profile and characterization of the chlorogenic acids in green Robusta coffee beans by LC-MS(n): identification of seven new classes of compounds

scientific article published on August 2010

Profiling and Quantification of Phenolics in Stevia rebaudiana Leaves

scientific article published on 07 October 2015

Profiling and Quantification of Regioisomeric Caffeoyl Glucoses in Berry Fruits

scientific article

Profiling and characterisation by liquid chromatography/multi-stage mass spectrometry of the chlorogenic acids in Gardeniae Fructus

scientific article published on November 2010

Profiling and characterization by LC-MSn of the chlorogenic acids and hydroxycinnamoylshikimate esters in maté (Ilex paraguariensis).

scientific article published in May 2010

Profiling and quantification of regioisomeric caffeoyl glucoses in Solanaceae vegetables

scientific article

Profiling the chlorogenic acids and other caffeic acid derivatives of herbal chrysanthemum by LC-MSn

scientific article published on 01 February 2007

Profiling the chlorogenic acids of aster by HPLC-MS(n)

scientific article published on 01 November 2006

Profiling, quantification and classification of cocoa beans based on chemometric analysis of carbohydrates using hydrophilic interaction liquid chromatography coupled to mass spectrometry.

scientific article published on 8 March 2018

Quantification of microbial uptake of quercetin and its derivatives using an UHPLC-ESI-QTOF mass spectrometry assay

scientific article

Repeated oral administration modulates the pharmacokinetic behavior of the chemopreventive agent phenethyl isothiocyanate in rats

scientific article published in March 2010

Synthesis and capsule formation of upper rim substituted tetra-acrylamido calix[4]arenes

scientific article published on 04 May 2005

Synthesis of novel enantiomerically pure tetra-carbohydrazide cyclophane macrocycles

scientific article published on 01 May 2012

Synthesis of tri-substituted biaryl based trianglimines: formation of C3-symmetrical and non-symmetrical regioisomers

scientific article published on 23 March 2011

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

scientific article published on 14 September 2016

Tea and coffee time with bacteria - Investigation of uptake of key coffee and tea phenolics by wild type E. coli.

scientific article

The chemistry of low molecular weight black tea polyphenols.

scientific article published on 10 February 2010

The inhibition of the mammalian DNA methyltransferase 3a (Dnmt3a) by dietary black tea and coffee polyphenols.

scientific article

The synthesis and conformation of oxygenated trianglimine macrocycles.

scientific article

The synthesis of trianglimines: on the scope and limitations of the [3 + 3] cyclocondensation reaction between (1R,2R)-diaminocyclohexane and aromatic dicarboxaldehydes

scientific article published in April 2003

Thermally-induced formation of taste-active 2,5-diketopiperazines from short-chain peptide precursors in cocoa

scientific article published on 09 March 2019

Tuning the size of macrocyclic cavities in trianglimine macrocycles

scientific article published on 14 April 2005

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

scientific article published on 26 July 2012

Unraveling the chemical composition of caramel

scientific article published on 14 March 2012

Unraveling the structure of the black tea thearubigins

scientific article

Variation of triacylglycerol profiles in unfermented and dried fermented cocoa beans of different origins

scientific article published on 31 May 2018

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 ⬇️

scientific article published on August 1, 2013

[A century of aspirin. The history of the most successful drug of the last ry]

scientific article published on 01 January 2000

List of works by Nikolai Kuhnert

A systematic study of carboxylic acids in negative ion mode electrospray ionisation mass spectrometry providing a structural model for ion suppression

Absolute bioavailability and dose-dependent pharmacokinetic behaviour of dietary doses of the chemopreventive isothiocyanate sulforaphane in rat

Analysis of minor low molecular weight carbohydrates in cocoa beans by chromatographic techniques coupled to mass spectrometry

Aseptic artificial fermentation of cocoa beans can be fashioned to replicate the peptide profile of commercial cocoa bean fermentations

Bioactivity in Rhododendron: A Systemic Analysis of Antimicrobial and Cytotoxic Activities and Their Phylogenetic and Phytochemical Origins

Biochemical fate of vicilin storage protein during fermentation and drying of cocoa beans.

Changes in low molecular weight carbohydrates in kale during development and acclimation to cold temperatures determined by chromatographic techniques coupled to mass spectrometry

Characterisation of "caramel-type" thermal decomposition products of selected monosaccharides including fructose, mannose, galactose, arabinose and ribose by advanced electrospray ionization mass spectrometry methods

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

Characterization by LC-MS(n) of four new classes of chlorogenic acids in green coffee beans: dimethoxycinnamoylquinic acids, diferuloylquinic acids, caffeoyl-dimethoxycinnamoylquinic acids, and feruloyl-dimethoxycinnamoylquinic acids

Characterization by LC-MS(n) of four new classes of p-coumaric acid-containing diacyl chlorogenic acids in green coffee beans

Characterization of commercial green tea leaves by the analysis of low molecular weight carbohydrates and other quality indicators

Characterization of triacylglycerols in unfermented cocoa beans by HPLC-ESI mass spectrometry

Chemistry inside molecular containers in the gas phase

Comparison and quantification of chlorogenic acids for differentiation of green Robusta and Arabica coffee beans

Comparison of the polyphenolic profile and antibacterial activity of the leaves, fruits and flowers of Rhododendron ambiguum and Rhododendron cinnabarinum.

Degradation of cocoa proteins into oligopeptides during spontaneous fermentation of cocoa beans

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

Differentiation of black tea infusions according to origin, processing and botanical varieties using multivariate statistical analysis of LC-MS data

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

Discriminating between the six isomers of dicaffeoylquinic acid by LC-MS(n).

Diversity of Kale (Brassica oleracea var. sabellica): Glucosinolate Content and Phylogenetic Relationships.

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

Experimentally modelling cocoa bean fermentation reveals key factors and their influences

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

Fourier transform ion cyclotron resonance mass spectrometrical analysis of raw fermented cocoa beans of Cameroon and Ivory Coast origin

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

Hierarchical scheme for LC-MSn identification of chlorogenic acids

Hierarchical scheme for liquid chromatography/multi-stage spectrometric identification of 3,4,5-triacyl chlorogenic acids in green Robusta coffee beans

High molecular weight non-polar hydrocarbons as pure model substances and in motor oil samples can be ionized without fragmentation by atmospheric pressure chemical ionization mass spectrometry

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

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

How to distinguish between feruloyl quinic acids and isoferuloyl quinic acids by liquid chromatography/tandem mass spectrometry

How to identify and discriminate between the methyl quinates of chlorogenic acids by liquid chromatography-tandem mass spectrometry

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

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

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

Identification and characterization of five new classes of chlorogenic acids in burdock (Arctium lappa L.) roots by liquid chromatography/tandem mass spectrometry

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

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

Identification and characterization of two new derivatives of chlorogenic acids in Arnica (Arnica montana L.) flowers by high-performance liquid chromatography/tandem mass spectrometry

Identification of Products from Thermal Degradation of Tryptophan Containing Pentapeptides: Oxidation and Decarboxylation

Identification of novel homologous series of polyhydroxylated theasinensins and theanaphthoquinones in the SII fraction of black tea thearubigins using ESI/HPLC tandem mass spectrometry

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

Investigating the Thermal Decomposition of Starch and Cellulose in Model Systems and Toasted Bread Using Domino Tandem Mass Spectrometry ⬇️

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

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

Investigation of isomeric flavanol structures in black tea thearubigins using ultraperformance liquid chromatography coupled to hybrid quadrupole/ion mobility/time of flight mass spectrometry

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.

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

MALDI-TOF Mass Spectrometry: Avoidance of Artifacts and Analysis of Caffeine-Precipitated SII Thearubigins from 15 Commercial Black Teas ⬇️

Mass spectrometric characterization of black tea thearubigins leading to an oxidative cascade hypothesis for thearubigin formation ⬇️

Metabolome Comparison of Bioactive and Inactive Rhododendron Extracts and Identification of an Antibacterial Cannabinoid(s) from Rhododendron collettianum.

Model system-based mechanistic studies of black tea thearubigin formation

Modulation of hepatic cytochromes P450 and phase II enzymes by dietary doses of sulforaphane in rats: Implications for its chemopreventive activity

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

On the activation of valerolactam with triflic anhydride: the synthesis of omega-trifluorosulfonamido dipeptides using a transpeptidation reaction under mild conditions

One size does not fit all--bacterial cell death by antibiotics cannot be explained by the action of reactive oxygen species

Origin and varietal based proteomic and peptidomic fingerprinting of Theobroma cacao in non-fermented and fermented cocoa beans

Origin-based polyphenolic fingerprinting of Theobroma cacao in unfermented and fermented beans.

Oxidative cascade reactions yielding polyhydroxy-theaflavins and theacitrins in the formation of black tea thearubigins: Evidence by tandem LC-MS ⬇️

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.

Probing the dynamic reversibility and generation of dynamic combinatorial libraries in the presence of bacterial model oligopeptides as templating guests of tetra-carbohydrazide macrocycles using electrospray mass spectrometry.

Probing the mechanism and dynamic reversibility of trianglimine formation using real‐time electrospray ionization time‐of‐flight mass spectrometry ⬇️

Profile and characterization of the chlorogenic acids in green Robusta coffee beans by LC-MS(n): identification of seven new classes of compounds

Profiling and Quantification of Phenolics in Stevia rebaudiana Leaves

Profiling and Quantification of Regioisomeric Caffeoyl Glucoses in Berry Fruits

Profiling and characterisation by liquid chromatography/multi-stage mass spectrometry of the chlorogenic acids in Gardeniae Fructus

Profiling and characterization by LC-MSn of the chlorogenic acids and hydroxycinnamoylshikimate esters in maté (Ilex paraguariensis).

Profiling and quantification of regioisomeric caffeoyl glucoses in Solanaceae vegetables

Profiling the chlorogenic acids and other caffeic acid derivatives of herbal chrysanthemum by LC-MSn

Profiling the chlorogenic acids of aster by HPLC-MS(n)

Profiling, quantification and classification of cocoa beans based on chemometric analysis of carbohydrates using hydrophilic interaction liquid chromatography coupled to mass spectrometry.

Quantification of microbial uptake of quercetin and its derivatives using an UHPLC-ESI-QTOF mass spectrometry assay

Repeated oral administration modulates the pharmacokinetic behavior of the chemopreventive agent phenethyl isothiocyanate in rats

Synthesis and capsule formation of upper rim substituted tetra-acrylamido calix[4]arenes

Synthesis of novel enantiomerically pure tetra-carbohydrazide cyclophane macrocycles

Synthesis of tri-substituted biaryl based trianglimines: formation of C3-symmetrical and non-symmetrical regioisomers

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