An Unambiguous Nomenclature for the Acyl-quinic Acids Commonly Known as Chlorogenic Acids

The history of the acyl-quinic acids is briefly reviewed, the merits and limitations of the various nomenclature systems applicable are critically compared, and their limitations are highlighted, in particular their inability to provide an unambiguous description of all quinic acid enantiomers and diastereoisomers and associated acyl-quinic acids. Recommendations are made for a nomenclature system that in combination with IUPAC numbering achieves this objective. A comprehensive set of structures for the quinic acid enantiomers and diastereoisomers is presented. The Supporting Information provides an explanation of trivial names and a decision tree to determine which quinic acid isomer a structure represents.

Comparative metabolite and genome analysis of tuber-bearing potato species

The cultivated potato Solanum tuberosum is unrivalled among crop plants for its wild relatives, which potentially represent an important source of genetic diversity to improve the nutritional value of potato varieties and understand metabolism regulation. The main aim of this research was to profile human health-related metabolites in a number of clones from 13 Solanum species. Results from HPLC-DAD and LC-ESI-MS analyses highlighted a high interspecific variability in the level of metabolites analysed. Ascorbic acid was confirmed to be the most abundant antioxidant in potato and chlorogenic acid the primary polyphenol. Generally, metabolite-based hierarchical clustering (HCL) and correlation networks did not group clones of identical species in the same cluster. This might be due to various factors, including the outcrossing nature of potato species, gene expression level and metabolic profiling techniques. Access to the genome sequence of S. tuberosum and S. commersonii allowed comparison of the genes involved in ascorbic acid, aromatic amino acid, phenylpropanoid and glycoalkaloid biosynthesis and helped interpret their respective pathways.

Neuroprotective Caffeoylquinic Acid Derivatives from the Flowers of Chrysanthemum morifolium

Three new caffeoylquinic acid derivatives, chrysanthemorimic acids A-C (1-3), and 11 known compounds (4-14) were isolated and characterized from the flowers of Chrysanthemum morifolium. Their structures were confirmed by spectroscopic data as well as by comparison of the experimental and calculated electronic circular dichroism spectra. Chrysanthemorimic acids A-C possess a rare 8-oxa-bicyclo[3.2.1]oct-3-en-2-one ring that is formed through a [5+2] cycloaddition of caffeoylquinic acid with a d-glucose derivative. Compounds 1-3, 6-8, 12, and 13 displayed significant effects against hydrogen peroxide-induced neurotoxicity in SH-SY5Y cells at 10 μM.

Chemical Constituents of Smilax china L. Stems and Their Inhibitory Activities against Glycation, Aldose Reductase, α-Glucosidase, and Lipase

The search for natural inhibitors with anti-diabetes properties has gained increasing attention. Among four selected Smilacaceae family plants, Smilax china L. stems (SCS) showed significant in vitro anti-glycation and rat lens aldose reductase inhibitory activities. Bioactivity-guided isolation was performed with SCS and four solvent fractions were obtained, which in turn yielded 10 compounds, including one phenolic acid, three chlorogenic acids, four flavonoids, one stilbene, and one phenylpropanoid glycoside; their structures were elucidated using nuclear magnetic resonance and mass spectrometry. All solvent fractions, isolated compounds, and stem extracts from plants sourced from six different provinces of South Korea were next tested for their inhibitory effects against advanced glycation end products, as well as aldose reductase. α-Glucosidase, and lipase assays were also performed on the fractions and compounds. Since compounds 3, 4, 6, and 8 appeared to be the superior inhibitors among the tested compounds, a comparative study was performed via high-performance liquid chromatography with photodiode array detection using a self-developed analysis method to confirm the relationship between the quantity and bioactivity of the compounds in each extract. The findings of this study demonstrate the potent therapeutic efficacy of SCS and its potential use as a cost-effective natural alternative medicine against type 2 diabetes and its complications.

Urea-Driven Epigallocatechin Gallate (EGCG) Permeation into the Ferritin Cage, an Innovative Method for Fabrication of Protein-Polyphenol Co-assemblies

The 8 nm diameter cavity endows the ferritin cage with a natural space to encapsulate food components. In this work, urea was explored as a novel medium to facilitate the formation of ferritin-polyphenol co-assemblies. Results indicated that urea (20 mM) could expand the 4-fold channel size of apo-red bean ferritin (apoRBF) with an increased initial iron release rate υ₀ (0.22 ± 0.02 μM min^-1) and decreased α-helix content (5.6%). Moreover, urea (20 mM) could facilitate the permeation of EGCG into the apoRBF without destroying the ferritin structure and thus form ferritin-EGCG co-assemblies (FECs) with an encapsulation ratio and loading capacity of 17.6 and 2.1% (w/w), respectively. TEM exhibited that FECs maintained a spherical morphology with a 12 nm diameter in size. Fluorescence analysis showed that urea intervention could improve the binding constant K [(1.22 ± 0.8) × 10⁴ M^-1] of EGCG to apoRBF. Furthermore, the EGCG thermal stability was significantly improved (20-60 °C) compared with free EGCG. Additionally, this urea-involved method was applicable for chlorogenic acid and anthocyanin encapsulation by the apoRBF cage. Thus, urea shows potential as a novel potential medium to encapsulate and stabilize bioactive polyphenols for food usage based on the ferritin protein cage structure.

Therapeutic mechanism of Yīn-Chén-Hāo decoction in hepatic diseases

Yīn-Chén-Hāo decoction (YCHD) is a traditional Chinese medicine formula composed of capillaris (Artemisia capillaris), gardenia (Gardenia jasminoides), and rhubarb (Rheum rhabarbarum) that is used for the treatment of damp-heat jaundice. In modern clinics, YCHD is mostly used for hepatic diseases. This review summarizes the biological activities of YCHD and its medical applications. The main active compounds of YCHD are chlorogenic acid, rhein, geniposide, emodin, and scoparone. The pharmacological actions of YCHD include inhibition of hepatic steatosis, apoptosis, necrosis, anti-inflammation, and immune regulation. YCHD could be developed as a new therapeutic strategy for the treatment of hepatic diseases.

Anti-Osteoclastic Activity of Artemisia capillaris Thunb. Extract Depends upon Attenuation of Osteoclast Differentiation and Bone Resorption-Associated Acidification Due to Chlorogenic Acid, Hyperoside, and Scoparone

The present study attempts to elucidate the anti-osteoporotic activity of Artemisia capillaris Thunb. in the form of anti-osteoclastic effect and responsible bioactive compounds. The contents of chlorogenic acid, caffeic acid, hyperoside, isoquercitrin, isochlorogenic acid A, and scoparone in Artemisia capillaris hydroethanolic extract (ACHE) were 38.53, 0.52, 4.07, 3.03, 13.90, and 6.59 mg/g, respectively. ACHE diminished osteoclast differentiation and bone resorption due to chlorogenic acid, hyperoside, and scoparone. In addition, ACHE attenuated acidification as well as reducing tumor necrosis factor receptor-associated factor 6 (TRAF6) expression and its association with vacuolar H⁺-adenosine triphosphatase (V-ATPase). Furthermore, chlorogenic acid, hyperoside, and scoparone from A. capillaris abrogated the association of V-ATPase with TRAF6, suggesting that the blockage of bone resorption by A. capillaris was partially mediated by reducing acidification through down-regulating interaction of V-ATPase with TRAF6 due to scoparone as well as chlorogenic acid and hyperoside. These results imply that the anti-osteoclastic effect of A. capillaris through down-regulating osteoclast differentiation and bone resorption may contribute to its anti-osteoporotic effect.

Sphingosine Kinase-1 Involves the Inhibitory Action of HIF-1α by Chlorogenic Acid in Hypoxic DU145 Cells

Hypoxia enhances cancer development in a solid tumor. Hypoxia-inducible factor-1 α (HIF-1α) is a transcription factor that is dominantly expressed under hypoxia in solid tumor cells and is a key factor that regulates tumor. HIF-1α regulates several target genes involved in many aspects of cancer progression, including angiogenesis, metastasis, anti-apoptosis and cell proliferation as well as imparts resistance to cancer treatment. In this study, we assessed Crataegus Pinnatifida Bunge var. typical Schneider ethanol extract (CPE) for its anti-cancer effects in hypoxia-induced DU145 human prostate cancer cell line. CPE decreased the abundance of HIF-1α and sphingosine kinase-1 (SPHK-1) in hypoxia-induced prostate cancer DU145 cells. CPE decreased HIF-1α and SPHK-1 as well as SPHK-1 activity. Chlorogenic acid (CA) is one of four major compounds of CPE. Compared to CPE, CA significantly decreased the expression of HIF-1α and SPHK-1 as well as SPHK-1 activity in hypoxia-induced DU145 cells. Furthermore, CA decreased phosphorylation AKT and GSK-3β, which are associated with HIF-1α stabilization and affected SPHK-1 in a concentration-dependent manner. We confirmed the mechanism of CA-induced inhibition of HIF-1α by SPHK-1 signaling pathway using SPHK-1 siRNA and SPHK inhibitor (SKI). CA decreased the secretion and cellular expression of VEGF, thus inhibiting hypoxia-induced angiogenesis. Treatment of DU145cells with SPHK1 siRNA and CA for 48 h decreased cancer cell growth, and the inhibitory action of SPHK siRNA and CA on cell growth was confirmed by decrease in the abundance of Proliferating cell nuclear antigen (PCNA).

Equilibrium adsorption of caffeic, chlorogenic and rosmarinic acids on cationic cross-linked starch with quaternary ammonium groups

In the present study, the equilibrium adsorption of caffeic acid (CA) and its derivatives, namely, chlorogenic (CGA) and rosmarinic (RA) acids on cationic cross-linked starch (CCS) with degree of substitution of quaternary ammonium groups of 0.42 have been investigated in relation to the structure and acidity of phenolic acids. The Langmuir, Freundlich and Dubinin-Radushkevich adsorption models have been used to describe the equilibrium adsorption of CA, CGA and RA from their initial solutions and solutions having the equimolar amount of NaOH at different temperatures. In the case of adsorption from the initial solutions of acids the values of adsorption parameters were closely related to the dissociation constants of investigated acids. According to the increasing effectiveness of adsorption, phenolic acids could be arranged in the following order: CA Collapse

Key Words

• Caffeic acid
• Cationic cross-linked starch
• Chlorogenic acid
• Equilibrium adsorption
• Rosmarinic acid

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MESH Headings

• Adsorption
• Caffeic Acids/chemistry
• Chlorogenic Acid/chemistry
• Cinnamates/chemistry
• Depsides/chemistry
• Hydrogen-Ion Concentration
• Quaternary Ammonium Compounds/chemistry
• Sodium Hydroxide/chemistry
• Solanum tuberosum/chemistry
• Starch/chemistry
• Temperature
• Rosmarinic Acid

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Grants Collapse

Characterization of Protein Tyrosine Phosphatase 1B Inhibition by Chlorogenic Acid and Cichoric Acid

Protein tyrosine phosphatase 1B (PTP1B) is a known regulator of the insulin and leptin signaling pathways and is an active target for the design of inhibitors for the treatment of type II diabetes and obesity. Recently, cichoric acid (CHA) and chlorogenic acid (CGA) were predicted by docking methods to be allosteric inhibitors that bind distal to the active site. However, using a combination of steady-state inhibition kinetics, solution nuclear magnetic resonance experiments, and molecular dynamics simulations, we show that CHA is a competitive inhibitor that binds in the active site of PTP1B. CGA, while a noncompetitive inhibitor, binds in the second aryl phosphate binding site, rather than the predicted benzfuran binding pocket. The molecular dynamics simulations of the apo enzyme and cysteine-phosphoryl intermediate states with and without bound CGA suggest CGA binding inhibits PTP1B by altering hydrogen bonding patterns at the active site. This study provides a mechanistic understanding of the allosteric inhibition of PTP1B.

Effects of thinned young apple polyphenols on the quality of grass carp (Ctenopharyngodon idellus) surimi during cold storage

The aim of this study was to investigate the effects of young apple polyphenols (YAP) on the quality of grass cap surimi (GCS) during storage at 4°C. The addition of YAP into GCS was found to be effective in delaying lipid oxidation, soluble myofibrillar protein (SMP) degradation and changes of L^∗, a^∗ and b^∗ values of GCS. Chlorogenic acid was screened to be the primary component showing preservative effects. YAP was shown to protect the functional properties of SMP during cold storage, retarding both the decrease in emulsifying activity and stability, and the increase in surface hydrophobicity of SMP. Additionally, the loss of gel strength and texture of GCS with YAP were significantly (P<0.05) lower than that of GCS without YAP during cold storage. Therefore, YAP may be developed as a natural antioxidant to maintain the quality and to extend the shelf life of freshwater fish surimi.

Reversal of Trimethyltin-Induced Learning and Memory Deficits by 3,5-Dicaffeoylquinic Acid

The antiamnesic effect of 3,5-dicaffeoylquinic acid (3,5-diCQA) as the main phenolic compound in Artemisia argyi H. extract on cognitive dysfunction induced by trimethyltin (TMT) (7.1 μg/kg of body weight; intraperitoneal injection) was investigated in order to assess its ameliorating function in mice. In several behavioral tests, namely, the Y-maze, passive avoidance, and Morris water maze (MWM) test, 3,5-diCQA significantly ameliorated learning and memory deficits. After the behavioral tests, brain tissues from the mice were analyzed to characterize the basis of the neuroprotective effect. Acetylcholine (ACh) levels increased, whereas the activity of acetylcholinesterase (AChE) decreased upon administration of 3,5-diCQA. In addition, 3,5-diCQA effectively protected against an increase in malondialdehyde (MDA) content, an increase in the oxidized glutathione (GSH) ratio, and a decline of total superoxide dismutase (SOD) level. 3,5-diCQA may prevent neuronal apoptosis through the protection of mitochondrial activities and the repression of apoptotic signaling molecules such as p-Akt, BAX, and p-tau (Ser 404).

Chlorogenic Acid Combined with Lactobacillus plantarum 2142 Reduced LPS-Induced Intestinal Inflammation and Oxidative Stress in IPEC-J2 Cells

This study was carried out to investigate protective effect of chlorogenic acid against lipopolysaccharide-induced inflammation and oxidative stress in intestinal epithelial cells. As a marker of inflammatory response, IL-6, IL-8, TNF-α mRNA and protein levels, furthermore, COX-2 mRNA level were followed up. Intracellular redox status and extracellular H2O2 level were also monitored by two fluorescent assays (DCFH-DA, Amplex Red). Moreover, the effect of gut microbiota metabolites in the above mentioned processes was taken into account in our model using Lactobacillus plantarum 2142 bacterial strain. Our data revealed that chlorogenic acid had significant lowering effect on the inflammatory response. Treatment with chlorogenic acid (25-50 μM) significantly decreased gene expression and concentration of proinflammatory cytokines IL-6 and IL-8 compared to LPS-treated cells. COX-2 and TNF-α mRNA levels were also reduced. Furthermore, chlorogenic acid reduced the level of reactive oxygen species in IPEC-J2 cells. Simultaneous application of chlorogenic acid and Lactobacillus plantarum 2142 supernatant resulted protective effect against LPS-induced inflammation and oxidative stress as well.

p-Hydroxyphenyl-pyranoanthocyanins: An Experimental and Theoretical Investigation of Their Acid-Base Properties and Molecular Interactions

The physicochemical properties of the wine pigments catechyl-pyranomalvidin-3-O-glucoside (PA1) and guaiacyl-pyranomalvidin-3-O-glucoside (PA2) are extensively revisited using ultraviolet (UV)-visible spectroscopy, dynamic light scattering (DLS) and quantum chemistry density functional theory (DFT) calculations. In mildly acidic aqueous solution, each cationic pigment undergoes regioselective deprotonation to form a single neutral quinonoid base and water addition appears negligible. Above pH = 4, both PA1 and PA2 become prone to aggregation, which is manifested by the slow build-up of broad absorption bands at longer wavelengths (λ ≥ 600 nm), followed in the case of PA2 by precipitation. Some phenolic copigments are able to inhibit aggregation of pyranoanthocyanins (PAs), although at large copigment/PA molar ratios. Thus, chlorogenic acid can dissociate PA1 aggregates while catechin is inactive. With PA2, both chlorogenic acid and catechin are able to prevent precipitation but not self-association. Calculations confirmed that the noncovalent dimerization of PAs is stronger with the neutral base than with the cation and also stronger than π–π stacking of PAs to chlorogenic acid (copigmentation). For each type of complex, the most stable conformation could be obtained. Finally, PA1 can also bind hard metal ions such as Al³⁺ and Fe³⁺ and the corresponding chelates are less prone to self-association.

Interactions of β-Conglycinin (7S) with Different Phenolic Acids-Impact on Structural Characteristics and Proteolytic Degradation of Proteins

p-Coumalic acid (PCA), caffeic acid (CA), gallic acid (GA) and chlorogenic acid (CGA) are the major phenolic acids that co-exist with soy protein components in foodstuffs. Surprisingly, there are only a handful of reports that describe their interaction with β-Conglycinin (7S), a major soy protein. In this report, we investigated the interaction between phenolic acids and soy protein 7S and observed an interaction between each of these phenolic acids and soy protein 7S, which was carried out by binding. Further analysis revealed that the binding activity of the phenolic acids was structure dependent. Here, the binding affinity of CA and GA towards 7S was found to be stronger than that of PCA, because CA and GA have one more hydroxyl group. Interestingly, the binding of phenolic acids with soy protein 7S did not affect protein digestion by pepsin and trypsin. These findings aid our understanding of the relationship between different phenolic acids and proteins in complex food systems.

Combination of chlorogenic acid and salvianolic acid B protects against polychlorinated biphenyls-induced oxidative stress through Nrf2

Caffeic acid derivatives (CADs) are well-known phytochemicals with multiple physiological and pharmacological activities. This study aimed to investigate the combined protective effects of CADs on PCB126-induced liver damages and oxidative stress in mice. Here, we used chemiluminescence and chose chlorogenic acid (CGA), salvianolic acid B (Sal B) as the best antioxidants. Then, mice were intragastrically administered with 60mg/kg/d CGA, Sal B, and CGA plus Sal B (1:1) for 3 weeks before exposing to 0.05mg/kg/d PCB126 for 2 weeks. We found that pretreatment with CGA, Sal B, and CGA plus Sal B effectively attenuated liver injury and cytotoxicity caused by PCB126, but improved the expressions of superoxide dismutase (SOD), glutathione reduced (GSH), heme oxygenase-1 (HO-1) and nuclear factor E2-related factor 2 (Nrf2), CGA plus Sal B especially, was found to have the best effects that indicated a synergetic protective effect. Taken together, as the Nrf2 regulates the cyto-protective response by up-regulating the expression of antioxidant genes, we suggested that CGA plus Sal B had a combined protection on PCB126-induced tissue damages and that the Nrf2 signaling might be involved.

Extrication process of chlorogenic acid in Crofton weed and antibacterial mechanism of chlorogenic acid on Escherichia coli

Crofton weed is a perennial herb and a biological intruding species. The present study firstly used the orthogonal test to compare the differences in extraction of chlorogenic acid in leaves and stems of Crofton weed by using three kinds of solvents, namely water, ethanol and ethyl acetate. The best effect was found by using ethonolic extraction of chlorogenic acid in Crofton weed. Further, by choosing Escherichia coli as test object, in-vitro antibacterial test was conducted to study the antimicrobial activities of chlorogenic acid by testing a series of indexes before and after the interaction between chlorogenic acid and Escherichia coli, to clarify the antibacterial mechanism of chlorogenic acid on Escherichia coli. Finally, by comparing the antibacterial activities of isochlorogenic acid A on Escherichia coli, it was concluded that both chlorogenic acid and isochlorogenic acid A showed antibacterial activities against Escherichia coli, wherein chlorogenic acid had a better antibacterial effect on Escherichia coli than isochlorogenic acid A.

Synergic application of spectroscopic and theoretical methods to the chlorogenic acid structure elucidation

Although chlorogenic acid (5-O-caffeoylquinic acid, 5CQA) is a dietary polyphenol known for its pharmacological and nutritional properties, its structural features have not been completely elucidated. This is the first study whose aim is to contribute to clarification of the 5CQA structure by comparing the experimental and simulated IR, Raman, (1)H NMR, (13)C NMR, and UV spectra. For this purpose, a comprehensive conformational analysis of 5CQA was performed to reveal its most stable conformations in the gas-state and solution (DMSO and methanol). The lowest-energy conformers were used to predict the spectra at two levels of theory: B3LYP-D3/and M06-2X/6-311+G(d,p) in combination with the CPCM solvation model. Both methods provide very good agreement between all experimental and simulated spectra, thus indicating correct arrangement of the atoms in the 5CQA molecule. The quinic moiety is characterized with directed hydrogen bonds, where the carboxylic hydrogen is not oriented towards the carbonyl oxygen of the carboxylic group, but towards the oxygen of the proximate hydroxyl group. In the gas-state the lowest-energy conformers are characterized with the O4H4⋯O9' hydrogen bond, whereas in the solvated state the structures with the O4H4⋯O10' hydrogen bond prevail. Knowing the fine structural details, i.e. the proper conformation of 5CQA, provides a solid base for all further investigations related to this compound.

The roasting process does not influence the extent of conjugation of coffee chlorogenic and phenolic acids

Understanding the bioavailability and metabolism of coffee compounds will contribute to identify the unknown biological mechanism(s) linked to their beneficial effects. The influence of the roasting process on the metabolism of coffee chlorogenic acids in humans was evaluated. In a randomized, double-blind, crossover study, 12 healthy volunteers consumed four instant coffees namely, high roasted coffee (HRC), low roasted coffee (LRC), unroasted coffee (URC), and in vitro hydrolyzed unroasted coffee (HURC). The sum of areas under the curve (AUC) ranged from 8.65-17.6 to 30.9-126 µM/h (P < 0.05) for HRC, LRC, URC, and HURC, respectively. The AUC of HRC, LRC, and URC was correlated with the initial level of phenolic acids in the coffee drinks. Despite different absorption rates, the extent of conjugation was comparable between HRC, LRC, and URC coffees but different for HURC. The most abundant circulating metabolites during the first 5 H were dihydroferulic acid (DHFA), caffeic acid-3'-O-sulfate (CA3S) and isoferulic-3'-O-glucuronide (iFA3G). DHFA and 5-4-dihydro-m-coumaric acid (mDHCoA) were the main metabolites in the period of 5-24 H. The phenolic compounds after consumption of HURC were most rapidly absorbed (Tmax 1 H) compared with the other coffees (Tmax between 9 and 11 H). Using coffees with different degrees of roasting we highlighted that in spite of different absorption rates the extent of conjugation of phenolic acids was comparable. In addition, by using a hydrolyzed unroasted coffee we demonstrated an increased absorption of phenolic acids in the small intestine. © 2016 BioFactors, 42(3):259-267, 2016.

In situ Identification of Labile Precursor Compounds and their Short-lived Intermediates in Plants using in vivo Nanospray High-resolution Mass Spectrometry

INTRODUCTION

Many secondary metabolites in plants are labile compounds which under environmental stress, are difficult to detect and track due to the lack of rapid in situ identification techniques, making plant metabolomics research difficult. Therefore, developing a reliable analytical method for rapid in situ identification of labile compounds and their short-lived intermediates in plants is of great importance.

OBJECTIVE

To develop under atmospheric pressure, a rapid in situ method for effective identification of labile compounds and their short-lived intermediates in fresh plants.

METHODOLOGY

An in vivo nanospray high-resolution mass spectrometry (HR-MS) method was used for rapid capture of labile compounds and their short-lived intermediates in plants. A quartz capillary was partially inserted into fresh plant tissues, and the liquid flowed out through the capillary tube owing to the capillary effect. A high direct current (d.c.) voltage was applied to the plant to generate a spray of charged droplets from the tip of the capillary carrying bioactive molecules toward the inlet of mass spectrometer for full-scan and MS/MS analysis.

RESULTS

Many labile compounds and short-lived intermediates were identified via this method: including glucosinolates and their short-lived intermediates (existing for only 10 s) in Raphanus sativus roots, alliin and its conversion intermediate (existing for 20 s) in Allium sativum and labile precursor compound chlorogenic acid in Malus pumila Mill.

CONCLUSION

The method is an effective approach for in situ identification of internal labile compounds and their short-lived intermediates in fresh plants and it can be used as an auxiliary tool to explore the degradation mechanisms of new labile plant compounds. Copyright © 2016 John Wiley & Sons, Ltd.

Synthesis and Application of Novel 3D Magnetic Chlorogenic Acid Imprinted Polymers Based on a Graphene-Carbon Nanotube Composite

A novel three-dimensional (3D) magnetic chlorogenic acid (CGA) imprinted polymer (MMIP) was prepared with novel carbon hybrid nanocomposite as the carrier, chlorogenic acid as the template molecule, and methacrylic acid as the functional monomer. The 3D MMIPs were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometer, and UV spectrometry in detail. The results showed that the imprinted layer was attached successfully on the surface of a 3D magnetic carbon hybrid nanocomposite. The adsorption performance of the 3D MMIPs was investigated, and the results showed that the 3D MMIPs exhibited high adsorption capacity and fast adsorption rate toward CGA with a maximum adsorption capacity of 10.88 mg g(-1). The extraction conditions involving washing solvent, the pH of eluent solvent, elution volume, and desorption time were also investigated in detail. Combined with high-performance liquid chromatography, the 3D MMIPs have been applied to successfully extract CGA from Eucommia leaf extract samples.

Chemical partitioning and antioxidant capacity of green coffee (Coffea arabica and Coffea canephora) of different geographical origin

Green coffee beans of Coffea arabica and Coffea canephora accessions from different geographical origin (Brazil, Colombia, Ethiopia, Honduras, Kenya, Mexico, Peru, Uganda and Vietnam) were extracted and the extracts analyzed by HPLC-ESI-MS/MS for the identification and quantification of chlorogenic acids and caffeine content. Principal component and cluster analyses were used to identify chemical patterns separating the different species and accessions based on their geographical origin. C. canephora showed always a higher caffeine content with respect to C. arabica, whereas the C. arabica accessions from Kenya showed a higher chlorogenic acids and a lower caffeine content. The antioxidant capacity of green coffee extracts was assayed by the reducing power and DPPH assays. The antioxidant capacity correlated with the chlorogenic acids content. The results show that the C. arabica from Kenya possesses the highest chlorogenic acids/caffeine ratio and, among the C. arabica accessions, the highest antioxidant capacity. Therefore, the C. arabica from Kenya is the most suitable green coffee source for nutraceutical applications because of its high antioxidant capacity and low caffeine content.

Application of Attenuated Total Reflectance-Fourier Transformed Infrared (ATR-FTIR) Spectroscopy To Determine the Chlorogenic Acid Isomer Profile and Antioxidant Capacity of Coffee Beans

The chlorogenic acid isomer profile and antioxidant activity of both green and roasted coffee beans are reported herein using ATR-FTIR spectroscopy combined with chemometric analyses. High-performance liquid chromatography (HPLC) quantified different chlorogenic acid isomer contents for reference, whereas ORAC, ABTS, and DPPH were used to determine the antioxidant activity of the same coffee bean extracts. FTIR spectral data and reference data of 42 coffee bean samples were processed to build optimized PLSR models, and 18 samples were used for external validation of constructed PLSR models. In total, six PLSR models were constructed for six chlorogenic acid isomers to predict content, with three PLSR models constructed to forecast the free radical scavenging activities, obtained using different chemical assays. In conclusion, FTIR spectroscopy, coupled with PLSR, serves as a reliable, nondestructive, and rapid analytical method to quantify chlorogenic acids and to assess different free radical-scavenging capacities in coffee beans.

Chicoric acid binds to two sites and decreases the activity of the YopH bacterial virulence factor

Chicoric acid (CA) is a phenolic compound present in dietary supplements with a large spectrum of biological properties reported ranging from antioxidant, to antiviral, to immunostimulatory properties. Due to the fact that chicoric acid promotes phagocytic activity and was reported as an allosteric inhibitor of the PTP1B phosphatase, we examined the effect of CA on YopH phosphatase from pathogenic bacteria, which block phagocytic processes of a host cell. We performed computational studies of chicoric acid binding to YopH as well as validation experiments with recombinant enzymes. In addition, we performed similar studies for caffeic and chlorogenic acids to compare the results. Docking experiments demonstrated that, from the tested compounds, only CA binds to both catalytic and secondary binding sites of YopH. Our experimental results showed that CA reduces activity of recombinant YopH phosphatase from Yersinia enterocolitica and human CD45 phosphatase. The inhibition caused by CA was irreversible and did not induce oxidation of catalytic cysteine. We proposed that inactivation of YopH induced by CA is involved with allosteric inhibition by interacting with essential regions responsible for ligand binding.

Evidences for Chlorogenic Acid--A Major Endogenous Polyphenol Involved in Regulation of Ripening and Senescence of Apple Fruit

To learn how the endogenous polyphenols may play a role in fruit ripening and senescence, apple pulp discs were used as a model to study the influences of chlorogenic acid (CHA, a major polyphenol in apple pulp) on fruit ripening and senescence. Apple ('Golden Delicious') pulp discs prepared from pre-climacteric fruit were treated with 50 mg L(-1) CHA and incubated in flasks with 10 mM MES buffer (pH 6.0, 11% sorbitol). Compared to the control samples, treatment with CHA significantly reduced ethylene production and respiration rate, and enhanced levels of firmness and soluble solids content of the pulp discs during incubation at 25°C. These results suggested that CHA could retard senescence of the apple pulp discs. Proteomics analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometry (MALDI-TOF/TOF) revealed that the expressions of several key proteins correlated to fruit ripening and senescence were affected by the treatment with CHA. Further study showed that treating the pulp discs with CHA remarkably reduced levels of lipoxygenase, β-galactosidase, NADP-malic enzyme, and enzymatic activities of lipoxygenase and UDP-glucose pyrophosphorylase, all of which are known as promoters of fruit ripening and senescence. These results could provide new insights into the functions of endogenous phenolic compounds in fruit ripening and senescence.

[Degradation kinetics of chlorogenic acid, cryptochlorogenic acid, and neochlorogenic acid at neutral and alkaline pH values]

The degradation kinetics of chlorogenic acid (5-CQA), cryptochlorogenic acid (4-CQA), and neochlorogenic acid (3-CQA) in aqueous solution at 37 degrees C and different pH values (7.05, 7.96, 9.25) were investigated in the present work. The results indicated that 3-, 4- and 5-CQA tended to remain stable in acidic pH circumstance, and unstable in neutral and alkaline pH circumstance. With the increase of the alkalinity, the degradation of 3-, 4- and 5-CQA was increased leading to a less amount of total CQA and was satisfactorily described by the Weibull equation. Meanwhile, caffeic acid was not detected after the degradation of CQA. Moreover, the degradation of 3-CQA and 5-CQA tended to be converted to 4-CQA, and the degradation of 4-CQA tended to be converted to 3-CQA rather than 5-CQA. The comparison of the degradation kinetics parameters of 3-, 4- and 5-CQA at neutral and alkaline pH values showed that the orders of the rate constant (k) values were 4-CQA > 3-CQA > 5-CQA, while the orders of the degradation half life (t½) values were 4-CQA < 3-CQA < 5-CQA, indicating the orders of the stabilities of 3-, 4- and 5-CQA at 37 degrees C and neutral and alkaline pH values were 4-CQA < 3-CQA < 5-CQA.

Chemical Constituents and LC-profile of Fresh Formosan Lonicera japonica Flower Buds

One new secoiridoid glucoside, ethylsecologanin dimethyl acetal (1), along with 15 known compounds, comprising six iridoid glucosides (2-7), six flavonoids (8-13), two sterol glucosides (14 and 15), and chlorogenic acid (16) were isolated from the flower buds of Formosan Lonicera japonica. The structures of these isolates were determined on the basis of mass and spectroscopic analyzes. In addition, the chemical profiles of fresh Formosan honeysuckle buds and the dried Chinese one were compared by HPLC with a PDA detector. The calibration curve of the active component, chlorogenic acid, was also provided. As a result of the constituent similarity, Formosan L.japonica can be an alternative to the Chinese honeysuckles.

Bioactive Compound Content and Cytotoxic Effect on Human Cancer Cells of Fresh and Processed Yellow Tomatoes

Tomato, as a fresh or processed product, has a high nutritional value due to its content of bioactive components such as phenolic compounds. Few studies describe the effect of processing on antioxidant content and the cancer cell growth inhibition activity. In this study we determined the phenolic and ascorbic acid content of three yellow tomato varieties, before and after thermal processing. Moreover, we determined the antioxidative power and tested the effects of tomato extracts on three human cancer cell lines. We found that the amount of phenolic acids (chlorogenic acid and caffeic acid) decreased in all the samples after processing, whereas the flavonoid content increased after the heat treatment in two samples. A cytotoxic effect of tomato extracts was observed only after processing. This result well correlates with the flavonoid content after processing and clearly indicates that processed yellow tomatoes have a high content of bioactive compounds endowed with cytotoxicity towards cancer cells, thus opening the way to obtain tomato-based functional foods.

Metal Complex Pigment Involved in the Blue Sepal Color Development of Hydrangea

Anthocyanins exhibit various vivid colors from red through purple to blue and are potential sources of food colorants. However, their usage is restricted because of their instability, especially as a blue colorant. The blue sepal color of Hydrangea macrophylla is due to a metal complex named "hydrangea-blue complex" composed of delphinidin 3-O-glucoside, 1, 5-O-caffeoylquinic acid, 2, and/or 5-O-p-coumaroylquinic acid, 3, as copigments, and Al(3+) in aqueous solution at approximately pH 4.0. However, the ratio of each component ins not stoichiometric, but is fluctuates within a certain range. The hydrangea-blue complex exists only in aqueous solution, exhibiting a stable blue color, but attempts at crystallization have failed; therefore, the structure remains obscure. To clarify the basis of the character of the hydrangea-blue pigment and to obtain its structural information, we studied the mixing conditions to reconstruct the same blue color as observed in the sepals. In highly concentrated sodium acetate buffer (6 M, pH 4.0) we could measure (1)H NMR of both the hydrangea-blue complex composed of 1 (5 mM), 2 (10 mM), and Al(3+) (10 mM) and a simple 1-Al(3+) complex. We also recorded the spectra of complexes composed with structurally different anthocyanins and copigments. Comparison of those signals indicated that in the hydrangea-blue complex 1 might be under equilibrium between chelating and nonchelating structures having an interaction with 2.

How to eliminate the formation of chlorogenic acids artefacts during plants analysis? Sea sand disruption method (SSDM) in the HPLC analysis of chlorogenic acids and their native derivatives in plants

The analytical procedures for determining plant constituents involve the application of sample preparation methods to fully isolate and/or pre-concentrate the analyzed substances. High-temperature liquid extraction is still applied most frequently for this purpose. The present paper shows that high-temperature extraction cannot be applied for the analysis of chlorogenic acids (CQAs) and their derivatives in plants as it causes the CQAs transformation leading to erroneous quantitative estimations of these compounds. Experiments performed on different plants (black elder, hawthorn, nettle, yerba maté, St John's wort and green coffee) demonstrate that the most appropriate method for the estimation of CQAs/CQAs derivatives is sea sand disruption method (SSDM) because it does not induce any transformation and/or degradation processes in the analyzed substances. Owing to the SSDM method application we found that the investigated plants, besides four main CQAs, contain sixteen CQAs derivatives, among them three quinic acids. The application of SSDM in plant analysis not only allows to establish a true concentration of individual CQAs in the examined plants but also to determine which chlorogenic acids derivatives are native plant components and what is their concentration level. What is even more important, the application of SSDM in plant analysis allows to eliminate errors that may arise or might have arisen in the study of chlorogenic acids and their derivatives in plant metabolism.

Radioprotective effect of chicory seeds against genotoxicity induced by ionizing radiation in human normal lymphocytes

The search for less-toxic radioprotective agents has led to a growing trend towards natural products. Protective effect of the methanolic extract of chicory seeds (MCS) was investigated against genotoxicity induced by ionizing radiation in human lymphocytes. Human peripheral blood samples were collected and incubated with MCS at different concentrations (10, 50, 100, and 200 μg/mL) for two hours. The whole blood samples were exposed in vitro to X-ray at dose 2.5 Gy. Then, the lymphocytes were cultured with mitogenic stimulation to determine the micronucleus in cytokinesis blocked binucleated cell. The methanolic extract at all doses significantly reduced the frequency of micronuclei in binucleated lymphocytes, as compared with similarly irradiated lymphocytes without any extract treatment. The maximum protection was observed at 200 μg/mL of MCS, it completely protected genotoxicity induced by ionizing radiation in human lymphocytes. The extract exhibited a concentration-dependent radical scavenging activity on 1,1-diphenyl-2-picryl hydrazyl free radicals. HPLC analysis of MCS showed this extract is containing chlorogenic acid as a phenolic compound. These data suggest that the radioprotective effect of methanolic extract of chicory seeds can be attributed to the presence of phenolic compounds such as chlorogenic acid which act as antioxidant agents.

Chlorogenic acid stability in pressurized liquid extraction conditions

Chlorogenic acids (CQAs) are phenolic compounds naturally occurring in all higher plants. They are potentially useful in pharmaceuticals, foodstuffs, food additives, and cosmetics due to their recently suggested biomedical activity. Hence, research interest in CQA properties, their isomers, and natural occurrence has been growing. Pressurized liquid extraction (PLE) is regarded as an effective and quick sample preparation method in plant analysis. The short time of PLE decreases the risk of chemical degradation of extracted compounds, thus increasing the attractiveness of its application. However, PLE applied for plant sample preparation is not free from limitations. We found that trans-5-O-caffeoylquinic acid (trans-5-CQA), the main CQA isomer, isomerizes to 3- and 4-O-caffeoylquinic acids and undergoes transesterification, hydrolysis, and reaction with water even in rapid PLE. Moreover, the number and concentration of trans-5-CQA derivatives formed in PLE strongly depends on extractant composition, its pH, and extraction time and temperature. It was not possible to find the PLE conditions in which the transformation process of trans-5-CQA would be eliminated.

Antidiabetic Effects of Aqueous Infusions of Artemisia herba-alba and Ajuga iva in Alloxan-Induced Diabetic Rats

The aqueous infusions of the aerial parts of Artemisia herba-alba Asso and Ajuga iva Schreber, prepared in accordance with the traditional procedure used in the local folk medicine, have been analysed for their composition and content of phytochemical constituents and examined for their antidiabetic effectiveness in alloxan-induced diabetic rats. Oral administration of A. herba-alba and A. iva infusions was studied in normal and alloxan-induced diabetic rats, which were randomly divided into nine groups, each group consisting of six animals. The drug preparations (100, 200, and 300 mg/kg b. w.) of each plant were given orally to the rats of each group twice daily for 15 days. Compositional analysis of the aqueous infusions revealed the presence of several polyphenols as main components. A. herba-alba infusion was characterised by mono- and di-cinnamoylquinic acids, with 5-caffeoylquinic (chlorogenic) acid being the main compound, followed by 3,5-dicaffeoylquinic acid. Vicenin-2 (apigenin 6,8-di-C-glucoside) appeared to be the most abundant among flavonoids. On the other hand, A. iva showed the exclusive presence of flavonoids, with the flavanone naringin present in relatively high levels together with several apigenin (flavone) derivatives. Oral administration of 300 mg/kg b. w. of the aqueous infusions of A. herba-alba and A. iva exhibited a significant reduction in blood glucose content, showing a much more efficient antidiabetic activity compared to glibenclamide, the oral hypoglycaemic agent used as a positive control in this study. These results suggest that A. herba-alba and A. iva possess significant antidiabetic activity, as they were able to improve the biochemical damage in alloxan-induced diabetes in rats.

Effect of Processing on the Traditional Chinese Herbal Medicine Flos Lonicerae: An NMR-based Chemometric Approach

The processing of medicinal materials, known as Pao Zhi in traditional Chinese medicine, is a unique part of traditional Chinese medicine and has been widely used for the preparation of Chinese materia medica. It is believed that processing can alter the properties and functions of remedies, increase medical potency, and reduce toxicity and side effects. Both processed and unprocessed Flos Lonicerae (flowers of Lonicera japonica) are important drug ingredients in traditional Chinese medicine. To gain insights on the effect of processing factors (heating temperature and duration) on the change of chemical composition, nuclear magnetic resonance combined with chemometric analysis was applied to investigate the processing of F. Lonicerae. Nuclear magnetic resonance spectral data were analyzed by means of a heat map and principal components analysis. The results indicated that the composition changed significantly, particularly when processing at the higher temperature (210 °C). Five chemical components, viz. 3,4-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, chlorogenic acid, and myo-inositol, whose concentration changed significantly during the processing, were isolated and identified. The patterns for the concentration change observed from nuclear magnetic resonance analysis during the processing were confirmed and quantitatively determined by ultrahigh-performance liquid chromatography analysis. The study demonstrated that a nuclear magnetic resonance-based chemometric approach could be a promising tool for investigation of the processing of herbal medicines in traditional Chinese medicine.

Influence of coffee genotype on bioactive compounds and the in vitro capacity to scavenge reactive oxygen and nitrogen species

The influence of green coffee genotype on the bioactive compounds and the in vitro antioxidant capacity against the principal reactive oxygen (ROO(•), H2O2, HO(•), and HOCl) and nitrogen (NO(•) and ONOO(-)) species of biological relevance was investigated. This is the first report on the capacity of green coffee to scavenge H2O2, HOCl, and NO(•). Variations in the contents of total chlorogenic acids (22.9-37.9 g/100 g), cinnamoyl-amino acid conjugates (0.03-1.12 g/100 g), trigonelline (3.1-6.7 g/100 g), and caffeine (3.9-11.8 g/100 g) were found. Hydrophilic extracts of Coffea canephora and Coffea kapakata were the most potent scavengers of ROO(•), H2O2, HO(•), NO(•), and ONOO(-) due to their chlorogenic acid contents, which were, on average, 30% higher than those found in Coffea arabica and Coffea racemosa. The results showed that genotype is a determinant characteristic in the bioactive compound contents and consequently in the antioxidant capacity of green coffee.

Assessment of total (free and bound) phenolic compounds in spent coffee extracts

Spent coffee is the main byproduct of the brewing process and a potential source of bioactive compounds, mainly phenolic acids easily extracted with water. Free and bound caffeoylquinic (3-CQA, 4-CQA, 5-CQA), dicaffeoylquinic (3,4-diCQA, 3,5-diCQA, 4,5-diCQA), caffeic, ferulic, p-coumaric, sinapic, and 4-hydroxybenzoic acids were measured by HPLC, after the application of three treatments (alkaline, acid, saline) to spent coffee extracts. Around 2-fold higher content of total phenolics has been estimated in comparison to free compounds. Phenolic compounds with one or more caffeic acid molecules were approximately 54% linked to macromolecules such as melanoidins, mainly by noncovalent interactions (up to 81% of bound phenolic compounds). The rest of the quantitated phenolic acids were mainly attached to other structures by covalent bonds (62-97% of total bound compounds). Alkaline hydrolysis and saline treatment were suitable to estimate total bound and ionically bound phenolic acids, respectively, whereas acid hydrolysis is an inadequate method to quantitate coffee phenolic acids.

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. The relevance of photochemical isomerization in agricultural practice was investigated using 120 samples of Stevia rebaudiana leave samples grown under defined cultivation conditions. Ratios of cis to trans chlorogenic acids were determined in leaf samples and correlated with climatic and harvesting conditions. The data indicate a clear correlation between the formation of cis-caffeoyl derivatives and sunshine hours prior to harvesting and illustrate the relevance of UV exposure to plant material affecting its phytochemical composition.

Chlorogenic acid-enriched extract from Eucommia ulmoides leaves inhibits hepatic lipid accumulation through regulation of cholesterol metabolism in HepG2 cells

CONTEXT

Eucommia ulmoides Oliver (Eucommiaceae) leaf exhibits beneficial lipid-lowering and anti-obesity effects. However, the mechanisms remain unknown.

OBJECTIVE

The objective of this study is to investigate the lipid-lowering effects of chlorogenic acid (CGA)-enriched extract from this plant (CAEF) in human hepatoma HepG2 cells, focusing on cholesterol metabolism.

MATERIALS AND METHODS

HepG2 cells were treated with CAEF (10, 20, 25, 40, 60, and 80 mg/L), CGA (0.3, 3, 30, 300, and 600 μmol/L), and simvastatin (0.1, 1, 10, 50, and 100 μmol/L) for 24 or 48 h. The cytotoxicity, Oil red O staining, total cholesterol, and triacylglycerol in supernatants were determined. The mRNA expression of genes involved in cholesterol metabolism was determined with RT-PCR. The protein expression of HMG-CoA reductase (HMGCR) was examined by immunocytochemistry and western-blot.

RESULTS

The IC50 values were 59.2 mg/L for CAEF, 335.9 μmol/L for CGA, and 10.5 μmol/L for simvastatin. By treating cells with CAEF (25 mg/L), CGA (30 μmol/L), or simvastatin (10 μmol/L) for 48 h, the efflux of total cholesterol and triacylglycerol was increased (CAEF, 4.06- and 31.00-folds; CGA, 2.94- and 2.17-folds; and simvastatin, 3.94- and 24.67-folds), and the cellular lipid droplets were reduced in Oil red O staining. CAEF and CGA increased mRNA expression of ABCA1, CYP7A1, and AMPKα2, while CAEF and simvastatin decreased SREBP2. However, their effects on LXRα mRNA expression were variable. Importantly, all drugs significantly inhibited protein expression of HMGCR at mRNA and protein levels.

DISCUSSION AND CONCLUSION

CAEF is a promising dietary supplement to prevent obesity and dyslipidemia and the effects appear to be due, at least in part, to regulating cholesterol metabolism through inhibition of HMGCR in HepG2 cells.

Role of degradation products of chlorogenic acid in the antioxidant activity of roasted coffee

Antioxidant activities of brewed coffees prepared from six commercial brands ranged from 63.13 ± 1.01 to 96.80 ± 1.68% at the highest levels tested. Generally, the degree of antioxidant activity of the brewed coffee was inversely proportional to the total chlorogenic acid concentration. A sample obtained from the major chlorogenic acid, 5-caffeoylquinic acid (5-CQA), heated at 250 °C exhibited potent antioxidant activity (79.12 ± 2.49%) at the level of 10 μg/mL, whereas unheated 5-CQA showed only moderate antioxidant activity (44.41 ± 0.27%) at the level of 100 μg/mL. Heat produced relatively high levels of pyrocatechol (2,809.3 μg/g) and 2-methoxy-4-vinylphenol (46.4 μg/g) from 5-CQA, and their antioxidant activity levels were 76.57 ± 3.00 and 98.63 ± 0.01%, respectively. The results of the present study suggest that roasting degrades chlorogenic acids to form potent antioxidants and thus plays an important role in the preparation of high-antioxidant low-acid coffee.

Production of chlorogenic acid and its derivatives in hairy root cultures of Stevia rebaudiana

Chlorogenic acid and its derivatives (CADs) are valuable bioactive plant secondary metabolites with many health benefits. In the present study, Stevia rebaudiana hairy root cultures were established, and the culture conditions for the production of CADs were optimized. The hairy roots were induced by coculture of S. rebaudiana leaves and Agrobacterium rhizogenes (C58C1) after infection, which were further verified by PCR detection of rolB and rolC genes. HPLC-MS and HPLC analysis showed that chlorogenic acid (3-caffeoylquinic acid, 3-CQA), 3,5-dicaffeoylquinic acid (3,5-CQA), and 4,5-dicaffeoylquinic acid (4,5-CQA) were the major CADs in the hairy roots. Eight single roots with rapid growth rate were selected. Among them, T3 had the highest yield of CADs. B5 medium supplemented with 40 g/L sucrose was more suitable for the production of CADs than others. Under optimal culture conditions, the total content of these three compounds reached 105.58 mg/g and total yield was 234.40 mg/100 mL.

Metabolomic fingerprinting of primed tobacco cells provide the first evidence for the biological origin of cis-chlorogenic acid

Previous studies suggest that only trans-isomers of chlorogenic acid (CGA) are naturally produced. Cis-isomers have been noted in some plant tissues exposed to different mechanical processes as well as untreated tobacco leaves exposed to sunlight. Very little, however, is known about the biological significance and origin of cis-isomers. Here we show for the first time the accumulation of cis-5-caffeoylquinic acid in cultured tobacco cells treated with different inducers of plant defence (lipopolysaccharides, flagellin peptide-22, chitosan, acibenzolar-S-methyl and isonitrosoacetophenone), without exposure to UV light and with a 2-fold (on average) increase in the concentration of the pool in comparison to non-stimulated cells. Our UHPLC-Q-TOF-MS and multivariate statistical results suggest the presence of a possible biological pathway responsible for the production of cis-CGAs in tobacco plants.

Impact of pH on the phytochemical profile of pasteurized peach purée during storage

Peach purée was exposed to different pH (2.5, 3.0, 3.5, 4.0, and 4.5) conditions, and its phytochemical alteration was estimated after fruit pasteurization and over a 90 day storage period at both 4 and 23 °C. During the 90 day storage, the study demonstrated a decrease in total antioxidant activity of 34-40% and a decrease in total phenolics of 18-20% at 4 °C and the corresponding decreases at 23 °C were 55-56 and 30-40%, respectively. Neochlorogenic acid (34 and 27%) and chlorogenic acid (34 and 37%) presented lower retention at the higher pH (4.5) for both storage temperatures. The degradation of carotenoids was higher at pH of 4.0 and 4.5, and the highest retention was obtained at pH 3.0 and 3.5. Zeaxanthin was the carotenoid most affected with loses of 60-68% at 4 °C and 56-75% for 23 °C. Storage time and temperature were critical factors for peach purée phytochemical profile, more than pH variation.

A method for the simultaneous determination of chlorogenic acid and sesquiterpene lactone content in industrial chicory root foodstuffs

A method for the simultaneous determination of free chlorogenic acids (CGA) and sesquiterpene lactones (STL) in chicory root and its dried (flour) and roasted (grain) forms is described. The method uses one extraction and one analysis for all chicory root products. Various solvents with low to high polarity, such as methanol, chloroform, or n-hexane, were tested alone, in combination in different proportions or with acidified or neutral aqueous solvent. The water/chloroform/methanol (30/30/40, v/v/v) mixture generated the best extraction yield, 21% higher than alcohol mixtures. The profiling of CGA and STL content was performed through a conventional HPLC-DAD method using a PFP core shell column in a fast single run. Good retention time and area repeatability (RDD mean % 0.46 and 5.6, resp.) and linearity (R2≥0.96) were obtained. The STL and chlorogenic acids levels determined were 254.7 and 100.2 μg/g of dry matter in the root, 792.5 and 1,547 μg/g in flour, and 160.4 and 822.5 μg/g in the roasted grains, respectively. With an average recovery of 106% and precision of 90%, this method is rapid, reproducible, and straightforward way to quantify the chlorogenic acids and STL in chicory raw material and end products.

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. All of them were extracted for the first time from this source and thirteen of them were not reported previously in nature. For the positive identification of chlorogenic acid glycosides by LC-MS(n), multiple reaction monitoring and targeted MS(n) experiments were performed. We have developed an LC-MS(n) method for the systematic identification of chlorogenic acid glycosides and were also able to discriminate between chlorogenic acids and their isobaric glycosides. It was also possible to discriminate between 5-O-(3'-O-caffeoyl glucosyl)quinic acid and 5-O-(4'-O-caffeoyl glucosyl)quinic acid by LC-MS(n). This method can be applied for the rapid and positive identification of chlorogenic acids and their glycosides in plant materials, food and beverages.

Dual catalytic activity of hydroxycinnamoyl-coenzyme A quinate transferase from tomato allows it to moonlight in the synthesis of both mono- and dicaffeoylquinic acids

Tomato (Solanum lycopersicum), like other Solanaceous species, accumulates high levels of antioxidant caffeoylquinic acids, which are strong bioactive molecules and protect plants against biotic and abiotic stresses. Among these compounds, the monocaffeoylquinic acids (e.g. chlorogenic acid [CGA]) and the dicaffeoylquinic acids (diCQAs) have been found to possess marked antioxidative properties. Thus, they are of therapeutic interest both as phytonutrients in foods and as pharmaceuticals. Strategies to increase diCQA content in plants have been hampered by the modest understanding of their biosynthesis and whether the same pathway exists in different plant species. Incubation of CGA with crude extracts of tomato fruits led to the formation of two new products, which were identified by liquid chromatography-mass spectrometry as diCQAs. This chlorogenate:chlorogenate transferase activity was partially purified from ripe fruit. The final protein fraction resulted in 388-fold enrichment of activity and was subjected to trypsin digestion and mass spectrometric sequencing: a hydroxycinnamoyl-Coenzyme A:quinate hydroxycinnamoyl transferase (HQT) was selected as a candidate protein. Assay of recombinant HQT protein expressed in Escherichia coli confirmed its ability to synthesize diCQAs in vitro. This second activity (chlorogenate:chlorogenate transferase) of HQT had a low pH optimum and a high Km for its substrate, CGA. High concentrations of CGA and relatively low pH occur in the vacuoles of plant cells. Transient assays demonstrated that tomato HQT localizes to the vacuole as well as to the cytoplasm of plant cells, supporting the idea that in this species, the enzyme catalyzes different reactions in two subcellular compartments.

[Determination of eleven major components and fingerprint chromatography for Reduning injection by UPLC]

A reliable method for simultaneous determinition of eleven representative components (neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, shanzhiside, geniposidic acid, genipin-1-β-D-gentiobioside, geniposide and secoxyloganin) in combination of chromatographic fingerpint analysis for Reduning injection was developed by ultra high-performance liquid chromatography (UPLC). The method was performed on an Agilent ZORBAX SB-C18 anlytical column (3. 0 mm x 100 mm, 1. 8 µm) with a guard column of Agilent UPLC Guard ZORBAX SB-C18 (3.0 mm x 5 mm) at the column temperature of 30 °C. The gradient mobile phase consisted of acetonitrile (A)-0. 1% phosphoric acid (B) with a flow rate of 0. 4 mL . min-1. The injection volumn was 2 µL. The detection wavelengths were set at 324 nm and 238 nm for quantit tive analysis and 225 nm for fingerpint chromatography. Neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, shanzhiside, geniposidic acid, genipin-1-β-D-gentiobioside, geniposide and secoxyloganin were baseline seperated with good linearity relationships (r >0. 999) between concentration and peak areas over the linear ranges. The average recoverys of the investigated compounds were 103.5%, 100. 2%, 103. 3%, 102. 8%, 101. 3%, 102. 8%, 97. 36%, 99. 62%, 98. 16%, 102. 8%, 99. 27%, respectively. Reduning injection of forty-five batches was analyzed by UPLC finge print chromatography. Thirty batches were selected to generate the reference fringerprint chromatography with fourteen common peaks. The similarity values between the reference fringerprint chromatography and the remaining fifteen batches were higher than 0. 99. The developed method was fast, accurate and sensitive. It could be used as a reference for the quality control of multiple components determination and fingerprint chromatography for Reduning injection in future.

Transformation of 5-O-caffeoylquinic acid in blueberries during high-temperature processing

Chlorogenic acid (CQA), an ester of caffeic with quinic acid, is a natural compound found in a wide array of plants. Although coffee beans are most frequently mentioned as plant products remarkably rich in CQAs, their significant amounts can also be found in many berries, for example, blueberries. This paper shows and discusses the thermal stability of the main CQA representative, that is, 5-O-caffeoylquinic acid (5-CQA), during high-temperature processing of blueberries (as in the production of blueberry foods) in systems containing sucrose in low and high concentration. It has been found that up to 11 components (5-CQA derivatives and its reaction product with water) can be formed from 5-CQA during the processing of blueberries. Their formation speed depends on the sucrose concentration in the processed system, which has been confirmed in the artificial system composed of 5-CQA water solution containing different amounts of the sugar.

[Effects of interaction of genotypes with environments on major latently fragrant substances of flue-cured tobacco in Baoshan of Yunnan, Southwest China]

To study the stability of major latently fragrant substances of flue-cured tobacco of different varieties in Baoshan of Yunnan, three tobacco cultivars (K326, Y87 and Y99) in two soil types at three test sites with different altitudes were tested. The contents of major latently fragrant substances were measured and the effects of genotypes, environments and their interactions were analyzed by AMMI model. The results showed that genotypes, environments and their interactions had significant effects on the contents of lutein, β-carotene, and chlorogenic acid. The rutin content was mainly influenced by genotypes while the major latently fragrant substances and their stability were affected significantly by the interactions of genotypes and environments. The contents of lutein, β-carotene, and chlorogenic acid increased remarkably with altitude, and their stabilities were strengthened to different extents. K326 adapted well to middle-lower altitude, while Y87 and Y99 adapted well to middle-higher altitude.

[Simultaneous determination of seven constituents in Lamiophlomis rotata by HPLC]

OBJECTIVE

To establish a new method for simultaneous determination of shanzhiside methyl ester, chlorogenic acid, 8-O-acetyl shanzhiside methylester, forsythiaside B, rutin, acteoside and galuteolin in Lamiophlomis rotata.

METHOD

Separation was performed on a Welchrom-C18 chromatographic column with acetonitrile-0.1% orthophosphoric acid as mobile phasewith gradient elution. The flow rate was 1.0 mL x min(-1). The column temperature was 30 degrees C, and the detection wavelength was set at 238 nm, 330 nm and 350 nm.

RESULT

The seven compounds were well separated with good linear correlations. The mean recoveries of seven compounds were 96.47%-102.2% (RSD 0.70%-2.2%).

CONCLUSION

There were good correlations among the seven compounds in the samples of aerial parts. The mean sum of shanzhiside methyl ester and 8-O-acetyl shanzhiside methylester in samples of aerial parts is 1.44%. The aerial parts have more kinds of composition and with higher content than that of underground parts in L. rotata, which was reasonable for the resonable use of the aerial part as medicinal part. The method was simple, repeatable and stable, which could be used for identification and quality evaluation of L. rotata.

[Research on correlation between odor and chemical compounds of Lonicera japonica]

This study aims to investigate the relationship between odor and contents of the chemical compounds in Lonicera japonica, including chlorogenic acid, galuteolin and polyphenols. High performance liquid chromatography (HPLC) was applied to determine the contents of chlorogenic acid and galuteolin in L. japonica. The ponptent of polyphenols was determined by UV-Vis Spectrophotometry. Electronic nose was used to extract and measure the odor of L. japonica. Then SPSS 17.0 software was employed for data processing. There is a significant positive correlation between the comprehensive index value of aroma and the contents of chlorogenic acid and polyphenols. The regression equations have been established. However, the relationship between the comprehensive index value and the content of galuteolin is not obvious. This is proof that the odor of L. japonica has close connection with the chemical compounds. Therefore, this research offered a new method for initially determine or predict the content of the chemical composition in L. japonica,