Study of new sources of six chlorogenic acids and caffeic acid

Development of an ic-CLEIA for precise detection of 3-CQA in herbs and patent medicines: ensuring quality control and therapeutic efficacy

Background

3-caffeoylquinic acid (3-CQA), a member of the chlorogenic acid family, possesses diverse pharmacological properties, such as scavenging, antioxidant, and antiapoptotic activity, rendering substantial value to alimentary consumables and therapeutic substances. However, the pervasiveness of non-standard practices, notably the misuse and abuse of indigenous botanicals, coupled with the inherent susceptibility of 3-CQA to degradation under light and heat exposure, engenders discernible disparateness in the quality profiles of the same kinds of herbs. Consequently, precise quantification of 3-CQA becomes imperative.

Methods

In this context, an artificial antigen was synthesized as a specific conjugate of 3-CQA and bovine serum albumin (3-CQA-BSA), followed by the generation of a monoclonal antibody (mAb) against the conjugate. Through optimization, a mAb-based indirect competitive chemiluminescence enzyme immunoassay (ic-CLEIA) was developed.

Results

It demonstrated an IC50 and the calibration range of 2.97 ng/mL and 0.64-13.75 ng/mL, respectively, outperforming the conventional enzyme-linked immunosorbent assay (ELISA). Notably, the ic-CLEIA displayed 10.71% cross-reactivity with 3,5-dicaffeoylquinic acid, alongside minimal cross-reactivity toward other isomeric counterparts and analogs. Validation experiments on herbs and Chinese patent medicines using ic-CLEIA, confirmed by high-performance liquid chromatography (HPLC) analysis, revealed a robust correlation coefficient of 0.9667 between the two modalities.

Conclusion

These findings unequivocally demonstrated that the proposed ic-CLEIA represents a viable and reliable analytical method for 3-CQA determination. This method holds significant potential for ensuring the quality control and therapeutic efficacy germane to herbs and patent medicines, spanning diverse therapeutic milieus and applications.

Adjuvant Properties of Caffeic Acid in Cancer Treatment

Caffeic acid (CA) is a polyphenol belonging to the phenylpropanoid family, commonly found in plants and vegetables. It was first identified by Hlasiwetz in 1867 as a breakdown product of caffetannic acid. CA is biosynthesized from the amino acids tyrosine or phenylalanine through specific enzyme-catalyzed reactions. Extensive research since its discovery has revealed various health benefits associated with CA, including its antioxidant, anti-inflammatory, and anticancer properties. These effects are attributed to its ability to modulate several pathways, such as inhibiting NFkB, STAT3, and ERK1/2, thereby reducing inflammatory responses, and activating the Nrf2/ARE pathway to enhance antioxidant cell defenses. The consumption of CA has been linked to a reduced risk of certain cancers, mitigation of chemotherapy and radiotherapy-induced toxicity, and reversal of resistance to first-line chemotherapeutic agents. This suggests that CA could serve as a useful adjunct in cancer treatment. Studies have shown CA to be generally safe, with few adverse effects (such as back pain and headaches) reported. This review collates the latest information from Google Scholar, PubMed, the Phenol-Explorer database, and ClinicalTrials.gov, incorporating a total of 154 articles, to underscore the potential of CA in cancer prevention and overcoming chemoresistance.

Characterization of ultrasound-assisted covalent binding interaction between β-lactoglobulin and dicaffeoylquinic acid: Great potential for the curcumin delivery

The low bioavailability and poor gastrointestinal instability of curcumin hampers its application in pharmaceutical and food industries. Thus, it is essential to explore efficient carrier (e.g. a combination of polyphenols and proteins) for food systems. In this study, covalent β-lactoglobulin (LG)-dicaffeoylquinic acids (DCQAs) complexes were prepared by combining ultrasound and free radical induction methods. Covalent interactions between LG and DCQAs were confirmed by analyzing reactive groups. Variations in secondary or tertiary structure and potential binding sites of covalent complexes were explored using Fourier transform infrared spectroscopy and circular dichroism. Results showed that the β-sheet content decreased and the unordered content increased significantly (P < 0.05). The embedding rate of curcumin in prepared LG-DCQAs complexes using ultrasound could reach 49 % - 62 %, proving that complexes could embed curcumin effectively. This study highlights the benefit of ultrasound application in fabrication of protein-polyphenol complexes for delivering curcumin.

Comparison of Physicochemical, Antioxidant, and Cytotoxic Properties of Caffeic Acid Conjugates

Spectroscopic studies (FT-IR, Raman, 1H, and 13C NMR, UV-VIS) of caffeic acid (CFA) and its conjugates, i.e., caftaric acid (CTA), cichoric acid (CA), and cynarin (CY), were carried out. The antioxidant activity of these compounds was determined by a superoxide dismutase (SOD) activity assay and the hydroxyl radical (HO•) inhibition assay. The cytotoxicity of these compounds was performed on DLD-1 cell lines. The molecules were theoretically modeled using the B3LYP-6-311++G(d,p) method. Aromaticity indexes (HOMA, I6, BAC, Aj), HOMO and LUMO orbital energies and reactivity descriptors, NBO electron charge distribution, EPS electrostatic potential maps, and theoretical IR and NMR spectra were calculated for the optimized model systems. The structural features of these compounds were discussed in terms of their biological activities.

Therapeutic Potential of Chlorogenic Acid in Chemoresistance and Chemoprotection in Cancer Treatment

Chemotherapeutic drugs are indispensable in cancer treatment, but their effectiveness is often lessened because of non-selective toxicity to healthy tissues, which triggers inflammatory pathways that are harmful to vital organs. In addition, tumors' resistance to drugs causes failures in treatment. Chlorogenic acid (5-caffeoylquinic acid, CGA), found in plants and vegetables, is promising in anticancer mechanisms. In vitro and animal studies have indicated that CGA can overcome resistance to conventional chemotherapeutics and alleviate chemotherapy-induced toxicity by scavenging free radicals effectively. This review is a summary of current information about CGA, including its natural sources, biosynthesis, metabolism, toxicology, role in combatting chemoresistance, and protective effects against chemotherapy-induced toxicity. It also emphasizes the potential of CGA as a pharmacological adjuvant in cancer treatment with drugs such as 5-fluorouracil, cisplatin, oxaliplatin, doxorubicin, regorafenib, and radiotherapy. By analyzing more than 140 papers from PubMed, Google Scholar, and SciFinder, we hope to find the therapeutic potential of CGA in improving cancer therapy.

Smartphone-based electrochemical sensor for cost-effective, rapid and on site detection of chlorogenic acid in herbs using biomass-derived hierarchically porous carbon synthesized by a soft-hard dual template method

To achieve excellent germplasm resource screening and ensure the quality control of herbal tea raw material, it is important to establish a cost-effective, rapid, and on site quantitative detection method for their bioactive constituents. We developed a smartphone-operated sensor for electrochemical detection of chlorogenic acid (CGA) using hierarchically porous carbon (DSiFPC), synthesized through a soft-hard dual template strategy with tannin acid as a carbon source, silica colloid as a hard template, and Pluronic F127 as a soft template. The DSiFPC modified glassy carbon electrode sensor showed excellent electrocatalytic ability towards CGA, with a wide linear range of 0.03-1 μM and a low limit of detection of 6.2 nM. It was successfully applied for detecting CGA in dried flowers of Lonicera japonica. Furthermore, a portable sensor utilizing a DSiFPC modified screen-printed electrode was employed for on site detection of CGA in fresh Eucommia ulmoides leaves, yielding satisfactory recoveries.

Chlorogenic acid: a review on its mechanisms of anti-inflammation, disease treatment, and related delivery systems

Chlorogenic acid is a bioactive compound ubiquitously present in the natural realm, lauded for its salient anti-inflammatory and antioxidant attributes. It executes its anti-inflammatory function by moderating the synthesis and secretion of inflammatory mediators, namely, TNF-α, IL-1β, IL-6, IL-8, NO, and PGE2. Concurrently, it modulates key signaling pathways and associated factors, including NF-κB, MAPK, Nrf2, and others, bestowing protection upon cells and tissues against afflictions such as cardio-cerebrovascular and diabetes mellitus. Nevertheless, the inherent low bioavailability of chlorogenic acid poses challenges in practical deployments. To surmount this limitation, sophisticated delivery systems, encompassing liposomes, micelles, and nanoparticles, have been devised, accentuating their stability, release mechanisms, and bioactivity. Given its innate anti-inflammatory prowess and safety profile, chlorogenic acid stands as a promising contender for advanced biomedical investigations and translational clinical endeavors.

Degradation, isomerization and stabilization of three dicaffeoylquinic acids under ultrasonic treatment at different pH

Dicaffeoylquinic acids (diCQAs) are found in a variety of edible and medicinal plants with various biological activities. An important issue is the low stability of diCQAs during extraction and food processing, resulting in the degradation and transformation. This work used 3,5-diCQA as a representative to study the influence of different parameters in ultrasonic treatment on the stability of diCQAs, including solvent, temperature, treatment time, ultrasonic power, duty cycle, and probe immersion depth. The generation of free radicals and its influence were investigated during the treatment. The stability of three diCQAs (3,5-diCQA, 4,5-diCQA and 3,4-diCQA) under the certain ultrasonic condition at different pH conditions was evaluated and found to decrease with the increase of pH, further weakened by ultrasonic treatment. Ultrasound was found to accelerate the degradation and isomerization of diCQAs. Different diCQAs showed different pattern of degradation and isomerization. The stability of diCQAs could be improved by adding epigallocatechin gallate and vitamin C.

Optimization of a New Ultrasound-Assisted Extraction Method of Caffeic Acid from the Aerial Parts of Coriandrum sativum by Using Experimental Design and Ultra-Performance Liquid Chromatography

Coriander (Coriandrum sativum L.) is among the most widely used medicinal and aromatic plants. It is well known for its multiple health benefits, most of which are correlated with its phenolic composition. Four phenolic compounds were identified in the extracts of aerial parts of coriander extracts, including caffeic acid, isoquercitrin, quercetin-3-O-glucuronide, and rutin. Caffeic acid was the major compound in the extracts. A Box–Behnken Design (BBD) was employed in conjunction with the response surface methodology (RSM) to develop an ultrasound-assisted extraction method for the determination of phenolic compounds in the aerial parts of coriander using the level of caffeic acid as the target response. The following working variables were evaluated: methanol level in the extraction solvent, temperature, sonication time, and liquid-to-solvent ratio. It was found that the methanol concentration is the most significant factor that influences the recovery of caffeic acid. The optimal extraction conditions were: 10 min as the extraction time, 70 °C as the temperature, 50% for methanol in water as the solvent, and 6.51 mL of solvent per gram of sample. The repeatability and reproducibility were calculated and RSD values below 6% were obtained in both cases. The new method was employed for the extraction of real coriander samples and it is suggested that this method could potentially be applied for quality control analyses.

Advances in Production of Hydroxycinnamoyl-Quinic Acids: From Natural Sources to Biotechnology

Hydroxycinnamoyl-quinic acids (HCQAs) are polyphenol esters formed of hydroxycinnamic acids and (-)-quinic acid. They are naturally synthesized by plants and some micro-organisms. The ester of caffeic acid and quinic acid, the chlorogenic acid, is an intermediate of lignin biosynthesis. HCQAs are biologically active dietary compounds exhibiting several important therapeutic properties, including antioxidant, antimicrobial, anti-inflammatory, neuroprotective, and other activities. They can also be used in the synthesis of nanoparticles or drugs. However, extraction of these compounds from biomass is a complex process and their synthesis requires costly precursors, limiting the industrial production and availability of a wider variety of HCQAs. The recently emerged production through the bioconversion is still in an early stage of development. In this paper, we discuss existing and potential future strategies for production of HCQAs.

Effects of Different Processing Methods of Coffee Arabica on Colour, Acrylamide, Caffeine, Chlorogenic Acid, and Polyphenol Content

An effect of a processing method (dry and wet) and a degree of roasting (light, medium, and dark) of 15 coffee (Coffea arabica) samples on the content of caffeine, chlorogenic acid (CQA), total polyphenols (TPP), acrylamide (AA), and on the colour parameters L*, a*, and b* was evaluated. Neither processing nor roasting affected caffeine content (p > 0.05). The degree of roasting accounted for 46% and 72% of explained variability of the CQA content and AA content, respectively (p < 0.05). AA content was in the range from 250 (wet-processed, light-roasted samples) to 305 µg·kg-1 (wet-processed, dark-roasted coffees), but the dark roasting only tended (p > 0.05) to increase AA content. Wet-processed, dry-roasted coffee had higher (p < 0.05) TPP content (48.5 mg·g-1) than its dry-processed, dry-roasted counterpart (42.5 mg·g-1); the method of processing accounted for 70% of explained variability of TPP. Both the method of processing and the degree of roasting affected the L*, a*, and b* values (p < 0.01), but the lower values (p < 0.05) of these parameters in the dark-roasted samples were found only within the wet processing. A negative correlation between the AA content and lightness (L*) was established (r = -0.39, p < 0.05). It was concluded that from the consumers' viewpoint, the results of the present study indicate relatively small differences in quality parameters of coffee irrespective of the method of processing or degree of roasting.

Coffee Chlorogenic Acids Incorporation for Bioactivity Enhancement of Foods: A Review

The demand of foods with high antioxidant capacity have increased and research on these foods continues to grow. This review is focused on chlorogenic acids (CGAs) from green coffee, which is the most abundant source. The main CGA in coffee is 5-O-caffeoylquinic acid (5-CQA). Coffee extracts are currently the most widely used source to enhance the antioxidant activity of foods. Due to the solubility of CGAs, their extraction is mainly performed with organic solvents. CGAs have been associated with health benefits, such as antioxidant, antiviral, antibacterial, anticancer, and anti-inflammatory activity, and others that reduce the risk of cardiovascular diseases, type 2 diabetes, and Alzheimer's disease. However, the biological activities depend on the stability of CGAs, which are sensitive to pH, temperature, and light. The anti-inflammatory activity of 5-CQA is attributed to reducing the proinflammatory activity of cytokines. 5-CQA can negatively affect colon microbiota. An increase in anthocyanins and antioxidant activity was observed when CGAs extracts were added to different food matrices such as dairy products, coffee drinks, chocolate, and bakery products. The fortification of foods with coffee CGAs has the potential to improve the functionality of foods.

New Approaches and advancement in drug development from phenolic p-coumaric acid

P-coumaric acid occurs as a common dietary polyphenol distributed in fruits, vegetables, and cereals in associated and free form. The toxicity profile of the drug is very low and it exhibits many pharmacological actions (antihypertensive, anti-inflammatory, anticancer, antimicrobial activity, antidiabetic, anticancer, and antioxidant effect). P-coumaric acid also acts as a free radical scavenger and inhibits various enzymes which generate free radicals. It is also used as the raw material for the preparation of preservatives, vanillin, sports foods, skin defense agents, and as a cross-linker for the formation of edible films and food gels. The current study is based upon biological effectiveness, molecular docking, SAR, sources of p-coumaric acid, and related derivatives.

1H-NMR and LC-MS Based Metabolomics Analysis of Potato (Solanum tuberosum L.) Cultivars Irrigated with Fly Ash Treated Acid Mine Drainage

1H NMR and LC-MS, commonly used metabolomics analytical platforms, were used to annotate the metabolites found in potato (Solanum tuberosum L.) irrigated with four different treatments based on FA to AMD ratios, namely: control (0% AMD; tap water), 1:1 (50% AMD), 3:1 (75% AMD is 75% FA: AMD), and 100% AMD (untreated). The effects of stress on plants were illustrated by the primary metabolite shifts in the region from δH 0.0 to δH 4.0 and secondary metabolites peaks were prominent in the region ranging from δH 4.5 to δH 8.0. The 1:3 irrigation treatment enabled, in two potato cultivars, the production of significantly high concentrations of secondary metabolites due to the 75% FA: AMD content in the irrigation mixture, which induced stress. The findings suggested that 1:1 irrigation treatment induced production of lower amounts of secondary metabolites in all crops compared to crops irrigated with untreated acid mine drainage treatment and with other FA-treated AMD solutions.

Caffeic acid modulates methane production and rumen fermentation in an opposite way with high-forage or high-concentrate substrate in vitro

BACKGROUND

Plant secondary metabolites, including tannins, saponins and phenolic acids, possess potential methane (CH₄ ) inhibition bioactivity. Caffeic acid (CA), as one of the typical phenolic acids, serves as a promising rumen CH₄ inhibitor, but the underlying mechanisms and investigations with typical formulated rations are still not well documented. Therefore, a batch culture study was conducted to investigate the effects of CA on methanogenesis, rumen fermentation and growth of ruminal microorganisms when high-forage or high-concentrate substrates are fermented.

RESULTS

After 48 h incubations, adding CA up to 40 g kg^-1 dry matter linearly reduced (P < 0.05) the disappearance of dry matter, neutral detergent fiber (NDFD), total gas, methanogenesis, total volatile fatty acid and 16S rDNA copy numbers of Ruminococcus albus and Butyrivibrio fibrisolvens, and increased 16S rDNA copy numbers of methanogens for the high-forage treatment. For the high-concentrate treatment, CA exerted opposite effects (P < 0.05) on the above variables, except that CA did not affect (P > 0.05)16S rDNA copy numbers of methanogens or R. albus.

CONCLUSION

Caffeic acid inhibited in vitro methanogenesis and rumen fermentation with high-forage substrate incubation. Contrarily, CA benefited in vitro fermentation and enhanced methanogenesis with high-concentrate substrate incubation. It suggests that CA modulates methanogenesis and rumen fermentation mainly by affecting the growth of cellulolytic bacteria in vitro. © 2020 Society of Chemical Industry.

Characterization and quantification of bioactive compounds from Ilex paraguariensis residue by HPLC-ESI-QTOF-MS from plants cultivated under different cultivation systems

Ilex paraguariensis is a perennial plant used in the production of mate tea, "chimarrão" and "tererê," cosmetics, and other food products. Its leaves are harvested every 12 or 18 months. Approximately 2 to 5 tons of residue are generated per hectare during the harvest. The bioactive composition of this residue has not been characterized to date. Therefore, this paper presents for the first time, the simultaneous characterization of the bioactive compounds of the leaves, thin branches, and thick branches (residue) from I. paraguariensis grown under two cultivation systems: "full sun" and "shaded." The identification and quantification of the compounds was performed using high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometer (HPLC-ESI-QTOF-MS). Consequently, 35 compounds were identified. The average dry weight of phenolic compounds in the residue was 4.1 g/100 g, whereas that in the bark of the residue was 12.9 g/100 g, which was similar to the content found in leaves. The same compounds were identified in the two cultivation systems but with a difference in their contents. While the "full sun" cultivation had a higher content of phenolic acids, the "shaded" cultivation had a higher content of flavonoids and saponins. It was found that the I. paraguariensis residue, particularly the bark, is rich in bioactive compounds, such as quinic, 3-caffeoylquinic, 5-cafefoylquinic, 3,5-dicaffeoylquinic, and 4,5-dicaffeoylquinic acids as well as rutin, and their contents vary according to the cultivation system. Therefore, this residue is an underutilized natural resource with a potential for industrial applications. PRACTICAL APPLICATION: Yerba mate producers will be able to choose the best cultivation system ("full sun" or "shaded") to increase the content of bioactive compounds. New products may be developed with yerba mate residue due to its high concentration of compounds that are beneficial to the human health. New destinations may be applied to yerba mate residue from the harvest pruning, adding commercial value to this unexplored natural resource.

A high-quality genome assembly of the eggplant provides insights into the molecular basis of disease resistance and chlorogenic acid synthesis

The eggplant (Solanum melongena L.) is one of the most important Solanaceae crops, ranking third for total production and economic value in its genus. Herein, we report a high-quality, chromosome-scale eggplant reference genome sequence of 1155.8 Mb, with an N50 of 93.9 Mb, which was assembled by combining PacBio long reads and Hi-C sequencing data. Repetitive sequences occupied 70.1% of the assembly length, and 35,018 high-confidence protein-coding genes were annotated based on multiple sources. Comparative analysis revealed 646 species-specific families and 364 positive selection genes, conferring distinguishing traits on the eggplant. We performed genome-wide comparative identification of disease resistance genes and discovered an expanded gene family of bacterial spot resistance in eggplant and pepper, but not in tomato and potato. The genes involved in chlorogenic acid synthesis were comprehensively characterized. Highly similar chromosomal distribution patterns of polyphenol oxidase genes were observed in the eggplant, tomato, and potato genomes. The eggplant reference genome sequence will not only facilitate evolutionary studies of the Solanaceae but also facilitate their breeding and improvement.

Chemical Composition, Nutritional Value, and Biological Evaluation of Tunisian Okra Pods (Abelmoschus esculentus L. Moench)

The aim of this work was to perform an unprecedented in-depth study on the bioactive phytochemicals of Abelmoschus esculentus L. Moench Tunisian landrace (Marsaouia). For this purpose, its nutritional, aroma volatile, and phenolic profiles were characterized, and sundry biological activities were assessed in vitro. The approximate composition revealed that total dietary fiber as the most abundant macronutrient, mainly insoluble dietary fiber, followed by total carbohydrates and proteins. In addition, okra pods were rich in K, Ca, Mg, organic acids, tocopherols, and chlorophylls. Gas Chromatography-Electron Impact Mass Spectrometry (GC-EIMS) analysis showed that oxygenated monoterpenes, sesquiterpene hydrocarbons, and phenylpropanoids were the predominant essential volatile components in A. esculentus pods. A total of eight flavonols were detected by High-Performance Liquid Chromatography coupled to a DAD detector and mass spectrometry by electrospray ionization (HPLC-DAD-MS/ESI); with quercetin-3-O-glucoside being the majority phenolic component, followed by quercetin-O-pentosyl-hexoside and quercetin-dihexoside. This pioneering study, evidences that Tunisian okra display promising antioxidant and cytotoxic actions, in addition to relevant inhibitory effects against α-amylase and α-glucosidase enzymes, and interesting analgesic activity.

Effects of chlorogenic acid on thermal stress tolerance in C. elegans via HIF-1, HSF-1 and autophagy

BACKGROUND

Chlorogenic acid (CGA) is a polyphenol widely distributed in plants and plant-derived food with antioxidant and protective activities against cell stress. Caenorhabditis elegans is a model organism particularly useful for understanding the molecular and biochemical mechanisms associated with aging and stress in mammals. In C. elegans, CGA was shown to improve resistance to thermal, while the underlying mechanisms that lead to this effect require further understanding.

PURPOSE

The present study was conducted to investigate the underlying molecular mechanisms behind CGA response conferring thermotolerance to C. elegans.

METHODS AND RESULTS

Signaling pathways that could be involved in the CGA-induced thermotolerance were evaluated in C. elegans strains with loss-of-function mutation. CGA-induced thermotolerance required hypoxia-inducible factor HIF-1 but no insulin pathway. CGA exposition (1.4 µM CGA for 18 h) before thermal stress treatment increased HIF-1 levels and activity. HIF-1 activation could be partly attributed to an increase in radical oxygen species and a decrease in superoxide dismutase activity. In addition, CGA exposition before thermal stress also increased autophagy just as hormetic heat condition (HHC), worms incubated at 36 °C for 1 h. RNAi experiments evidenced that autophagy was increased by CGA via HIF-1, heat-shock transcription factor HSF-1 and heat-shock protein HSP-16 and HSP-70. In contrast, autophagy induced by HHC only required HSF-1 and HSP-70. Moreover, suppression of autophagy induction showed the significance of this process for adapting C. elegans to cope with thermal stress.

CONCLUSION

This study demonstrates that CGA-induced thermotolerance in C. elegans is mediated by HIF-1 and downstream, by HSF-1, HSPs and autophagy resembling HHC.