Anti-human immunodeficiency virus activity of 3,4,5-tricaffeoylquinic acid in cultured cells of lettuce leaves

Mechanism of PRRSV infection and antiviral role of polyphenols

Porcine reproductive and respiratory syndrome (PRRS) is associated with the endemic outbreak of fever, anorexia, and abortion in pregnant sows, resulting in an enormous economic impact on the global swine industry. Current mainstream prophylactic agents and therapies have been developed to prevent PRRSV infection; however, they have limited efficacy. Therefore, there is an urgent need to develop novel antiviral strategies to prevent PRRSV infection and transmission. The identification of new PRRSV entry mediators, such as MYH9 and HSPA8; viral apoptotic mimicry; and TIM-induced macropinocytosis, to facilitate infection has led to a novel molecular understanding of the PRRSV infection mechanism, which can be utilized in the development of prophylactic agents and therapies for PRRSV infection. Polyphenols, complex chemical molecules with abundant biological activities derived from microorganisms and plants, have demonstrated great potential for controlling PRRSV infection via different mechanisms. To explore new possibilities for treating PRRSV infection with polyphenols, this review focuses on summarizing the pathogenesis of PRRSV, reviewing the potential antiviral mechanisms of polyphenols against PRRSV, and addressing the challenges associated with the widespread use of polyphenols.

The role and mechanism of TCM in the prevention and treatment of infectious diseases

The constant presence of infectious diseases poses an everlasting threat to the entire world. In recent years, there has been an increased attention toward the application of traditional Chinese medicine (TCM) in the treatment of emerging infectious diseases, as it has played a significant role. The aim of this article is to provide a concise overview of the roles and mechanisms of TCM in treating infectious diseases. TCM possesses the ability to modulate relevant factors, impede signaling pathways, and inhibit microbial growth, thereby exhibiting potent antiviral, antibacterial, and anti-inflammatory effects that demonstrate remarkable efficacy against viral and bacterial infections. This article concludes that the comprehensive regulatory features of Chinese herbal medicines, with their various components, targets, and pathways, result in synergistic effects. The significance of Chinese herbal medicines in the context of infectious diseases should not be underestimated; however, it is crucial to also acknowledge their underutilization. This paper presents constructive suggestions regarding the challenges and opportunities faced by Chinese medicines. Particularly, it emphasizes the effectiveness and characteristics of Chinese medicines in the treatment of infectious diseases, specifying how these medicines' active substances can be utilized to target infectious diseases. This perspective is advantageous in facilitating researchers' pharmacological studies on Chinese medicines, focusing on the specific points of action. The mechanism of action of Chinese herbal medicines in the treatment of infectious diseases is comprehensively elucidated in this paper, providing compelling evidence for the superior treatment of infectious diseases through Chinese medicine. This information is favorable for advancing the development of TCM and its potential applications in the field of infectious diseases.

AlZain M, Noman O, Parvez MK, Bousta D, Bari A. Phytochemical, Morphological and Genetic Characterisation of Anacyclus pyrethrum var. depressus (Ball.) Maire and Anacyclus pyrethrum var. pyrethrum (L.) Link

The present study is based on a multidisciplinary approach carried out for the first time on Anacyclus pyrethrum var. pyrethrum and Anacyclus pyrethrum var. depressus, two varieties from the endemic and endangered medicinal species listed in the IUCN red list, Anacyclus pyrethrum (L.) Link. Therefore, morphological, phytochemical, and genetic characterisations were carried out in the present work. Morphological characterisation was established based on 23 qualitative and quantitative characters describing the vegetative and floral parts. The phytochemical compounds were determined by UHPLC. Genetic characterisation of extracted DNA was subjected to PCR using two sets of universal primers, rbcL a-f/rbcL a-R and rpocL1-2/rpocL1-4, followed by sequencing analysis using the Sanger method. The results revealed a significant difference between the two varieties studied. Furthermore, phytochemical analysis of the studied extracts revealed a quantitative and qualitative variation in the chemical profile, as well as the presence of interesting compounds, including new compounds that have never been reported in A. pyrethrum. The phylogenetic analysis of the DNA sequences indicated a similarity percentage of 91%. Based on the morphological characterisation and congruence with the phytochemical characterisation and molecular data, we can confirm that A. pyrethrum var. pyrethrum and A. pyrethrum var. depressus represent two different taxa.

Phenolic Compounds in Salicornia spp. and Their Potential Therapeutic Effects on H1N1, HBV, HCV, and HIV: A Review

Despite public health risk mitigation measures and regulation efforts by many countries, regions, and sectors, viral outbreaks remind the world of our vulnerability to biological hazards and the importance of mitigation actions. The saltwater-tolerant plants in the Salicornia genus belonging to the Amaranthaceae family are widely recognized and researched as producers of clinically applicable phytochemicals. The plants in the Salicornia genus contain flavonoids, flavonoid glycosides, and hydroxycinnamic acids, including caffeic acid, ferulic acid, chlorogenic acid, apigenin, kaempferol, quercetin, isorhamnetin, myricetin, isoquercitrin, and myricitrin, which have all been shown to support the antiviral, virucidal, and symptom-suppressing activities. Their potential pharmacological usefulness as therapeutic medicine against viral infections has been suggested in many studies, where recent studies suggest these phenolic compounds may have pharmacological potential as therapeutic medicine against viral infections. This study reviews the antiviral effects, the mechanisms of action, and the potential as antiviral agents of the aforementioned phenolic compounds found in Salicornia spp. against an influenza A strain (H1N1), hepatitis B and C (HBV/HCV), and human immunodeficiency virus 1 (HIV-1), as no other literature has described these effects from the Salicornia genus at the time of publication. This review has the potential to have a significant societal impact by proposing the development of new antiviral nutraceuticals and pharmaceuticals derived from phenolic-rich formulations found in the edible Salicornia spp. These formulations could be utilized as a novel strategy by which to combat viral pandemics caused by H1N1, HBV, HCV, and HIV-1. The findings of this review indicate that isoquercitrin, myricetin, and myricitrin from Salicornia spp. have the potential to exhibit high efficiency in inhibiting viral infections. Myricetin exhibits inhibition of H1N1 plaque formation and reverse transcriptase, as well as integrase integration and cleavage. Isoquercitrin shows excellent neuraminidase inhibition. Myricitrin inhibits HIV-1 in infected cells. Extracts of biomass in the Salicornia genus could contribute to the development of more effective and efficient measures against viral infections and, ultimately, improve public health.

Identification and evaluation of a novel tribenzamide derivative as an inhibitor targeting the entry of the respiratory syncytial virus

Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract infections in infants, the elderly, and the immunocompromised, yet no licensed vaccine and only limited therapeutic options for prevention and treatment are available, which poses a global health challenge and emphasizes the urgent medical need for novel antiviral agents. In the current study, a novel potent small molecule inhibitor of RSV was identified by performing a screening and structure optimization campaign, wherein a naturally occurring dicaffeoylquinic acid (DCQA) compound served as a chemical starting point. The reported benzamide derivative inhibitor, designated as 2f, was selected for its improved stability and potent antiviral activity from a series of investigated structurally related compounds. 2f was well tolerated by cells and able to inhibit RSV infection with a half maximal inhibitory concentration (IC₅₀) of 35 nM and a favorable selectivity index (SI) of 3742. Although the exact molecular target for 2f is not known, in vitro mechanism of action investigations revealed that the compound inhibits the early stage of infection by interacting with RSV virion and interferes primarily with the attachment and potentially with the virus-cell fusion step. Moreover, intranasal administration of 2f to mice simultaneously or prior to intranasal infection with RSV significantly decreased viral load in the lungs, pointing to the in vivo potential of the compound. Our results suggest that 2f is a viable candidate for further preclinical development and evaluation as an antiviral agent against RSV infections.

Identification of Anti-HIV Biomarkers of Helichrysum Species by NMR-Based Metabolomic Analysis

Several species of the Helichrysum genus have been used ethnobotanically to treat conditions that we today know have been caused by viral infections. Since HIV is a modern disease with no ethnobotanical history, we commenced with a study on the anti-HIV activity of several Helichrysum species. Drug discovery of small molecules from natural resources that is based on the integration of chemical and biological activity by means of metabolomical analyses, enables faster and a more cost-effective path to identify active compounds without the need for a long process of bioassay-guided fractionation. This study used metabolomics to identify anti-HIV compounds as biomarkers from 57 Helichrysum species in a combined study of the chemical and biological data of two previous studies. In the OPLS-DA and hierarchical cluster analyses, anti-HIV activity data was included as a secondary observation, which assisted in the correlation of the phytochemical composition and biological activity of the samples. Clear grouping revealed similarity in chemical composition and bioactivity of the samples. Based on the biological activity of polar extracts, there was a distinct phytochemical difference between active and non-active groups of extracts. This NMR-based metabolomic investigation showed that the chlorogenic acids, compounds with cinnamoyl functional groups, and quinic acid were the most prominent compounds in the Helichrysum species with anti-HIV activity. This study further revealed that the chlorogenic acid type compounds and quinic acid are biomarkers for anti-HIV activity.

Exploring phytochemical constituents of Achillea arabica Kotschy. ethanolic flower extract by LC-MS/MS and its possible antioxidant and antidiabetic effects in diabetic rats

The aim of this study was to reveal the antidiabetic and antioxidant effects of ethanolic lyophilized extract of Achillea arabica flower extract against streptozotosine (STZ)-induced in diabetic rats and to determine its phytochemical content by liquid chromatography with tandem mass spectrometry (LC-MS/MS). After toxicity test, 35 female rats were divided into five groups. Control, diabetes mellitus (DM), A.arabica (400 mg/kg) extract, DM + A. arabica (400 mg/kg) extract and DM + Glibenclamide (2 mg/kg). It was determined that while diabetic rats treated A.arabica plant extract significantly decreased blood glucose level, serum glucose, HbA1c, liver and kidney damage biomarker levels, and malondialdehyde (MDA) content compared to the DM group, it caused fluctuations in antioxidant enzyme levels. According to LC-MS/MS results of A. arabica flower extract, quinic acid (2439.9 μg/g), cyranoside (858.4 μg/g), chlorogenic acid (698.7 μg/g), and cosmosiin (347.8 μg/g) were determined as major compounds, respectively. In addition, two new compounds were determined in this extract according to nuclear magnetic resonance (NMR) and Mass analyses and these compounds were named edremitine and achillosine, respectively. Thus, A.arabica flower extract has possible therapeutic effects to prevent high blood glucose level and oxidative stress caused by DM in liver and kidney via its high phenolic content.

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.

In silico evaluation of COVID-19 main protease interactions with honeybee natural products for discovery of high potential antiviral compounds

This research investigates antiviral potential of extracted honeybee products against COVID-19 main protease (Mpro) by computational methods. The crystal structure of COVID-19 Mpro was obtained from the protein data bank. Six synthetic drugs with antiviral properties were used as control samples in order to compare the results with those of natural ligands. The six honeybee components, namely 3,4,5-Tricaffeoylquinic acid, Kaempferol-3-O-glucoside, (E)-2'-Geranyl-3',4',7-Trihydroxyflavanone, 6-Cinnamylchrysin, (+)-Pinoresinol, and (24E)-3-Oxo-27,28-dihydroxycycloart-24-en-26-oic acid, have represented the lowest binding energies of -9.0, -8.5, -8.2, -7.8, -7.7, -7.3 and -6.7 Kcal/mol, respectively. These natural inhibitors were then picked for further investigations on their pharmacokinetic features. Also a 150 ns of Molecular dynamics simulations were carried out in order to evaluate their effects on protein structure and dynamics. The 3, 4, 5-Tricaffeoylquinic acid is hopefully proposed for COVID-19 Mpro inhibition if further in vitro, in vivo, and clinical trial studies will approve its effectiveness against COVID-19.

Chlorogenic acid is a positive regulator of MDA5, TLR7 and NF-κB signaling pathways mediated antiviral responses against Gammacoronavirus infection

Chlorogenic acid (CGA) is a phenolic compound that has been well studied for its antiviral, anti-inflammatory and immune stimulating properties. This research was aimed to focus on the antiviral properties of CGA on infectious bronchitis virus (IBV) in vivo and in vitro for the very first time. The outcome of in vitro experiments validated that, out of five previously reported antiviral components, CGA significantly reduced the relative mRNA expression of IBV-N in CEK cells. At high concentration (400 mg/kg), CGA supplementation reduced IBV-N mRNA expression levels and ameliorated the injury in trachea and lungs. The mRNA expression levels of IL-6, IL-1β, IL-12, and NF-κB were considerably turned down, but IL-22 and IL-10 were enhanced in trachea. However, CGA-H treatment had considerably increased the expression levels of MDA5, MAVS, TLR7, MyD88, IRF7, IFN-β and IFN-α both in trachea and lungs. Moreover, CGA-H notably induced the CD3+, CD3+ CD4+ and CD4+/CD8+ proliferation and significantly increased the IgA, IgG, and IgM levels in the serum. In conclusion, these results showed that at high concentration CGA is a strong anti-IBV compound that can effectively regulate the innate immunity through MDA5, TLR7 and NF-κB signaling pathways and have the potential to induce the cell mediated and humoral immune response in IBV infected chickens.

In vitro cultivation of tansy (Tanacetum vulgare L.): a tool for the production of potent pharmaceutical agents

In this study, tansy (Tanacetum vulgare L.) in vitro culture was established from seeds collected from natural populations. The multiplication of plantlets was conducted through shoot tips that exhibited potent apical growth and regeneration capacities on basal medium (BM), without the addition of any plant growth regulators (PGRs). PGRs were also omitted for the establishment and cultivation of tansy root cultures. Both abaxial and adaxial leaf surfaces of in vitro micropropagated plantlets were covered with glandular biseriate trichomes. Histochemical staining showed that glandular secretions were rich in lipid and terpene compounds, confirmed by GC-MS analysis of essential oil (EO). In the total EO, similar portions of oxygenated monoterpenes (38.5% m/m) and oxygenated sesquiterpenes (22.6% m/m) were detected. Chemical profiles of methanol extracts of in vitro cultured tansy shoots and roots varied in quantity and quality from those obtained from wild-growingtansy. HPLC analysis indicated that the methanol extracts of in vitro cultured roots were the richest in 3,5-O-dicaffeoylquinic acid (3,5-O-DCQA), in which the concentration was 6 times higher (10.220 mg/g DW) than that in the extract obtained from roots of wild-growing tansy (1.684 mg/g DW). This result is noticeable in the manner of industrial production of biologically active 3,5-O-DCQA that has been shown to have antioxidant, hepatoprotective, antiviral, antimutagenic, and immunomodulatory activity. Biotechnological interventions on secondary metabolite production taking place in trichomes could further enhance the production of some important tansy metabolites and further investigation will be directed toward the elucidation of the pharmaceutical potential of tansy in vitro obtained metabolites, as mixtures or single moieties.

Compounds with Antiviral, Anti-Inflammatory and Anticancer Activity Identified in Wine from Hungary's Tokaj Region via High Resolution Mass Spectrometry and Bioinformatics Analyses

(1) Background: Wine contains a variety of molecules with potential beneficial effects on human health. Our aim was to examine the wine components with high-resolution mass spectrometry including high-resolution tandem mass spectrometry in two wine types made from grapes with or without the fungus Botrytis cinerea, or "noble rot". (2) For LC-MS/MS analysis, 12 wine samples (7 without and 5 with noble rotting) from 4 different wineries were used and wine components were identified and quantified. (3) Results: 288 molecules were identified in the wines and the amount of 169 molecules was statistically significantly different between the two wine types. A database search was carried out to find the molecules, which were examined in functional studies so far, with high emphasis on molecules with antiviral, anti-inflammatory and anticancer activities. (4) Conclusions: A comprehensive functional dataset related to identified wine components is also provided highlighting the importance of components with potential health benefits.

Current Advances in Naturally Occurring Caffeoylquinic Acids: Structure, Bioactivity, and Synthesis

Caffeoylquinic acids (CQAs) are a broad class of secondary metabolites that have been found in edible and medicinal plants from various families. It has been 100 years since the discovery of chlorogenic acid in 1920. In recent years, a number of naturally derived CQAs have been isolated and structurally elucidated. Accumulated evidence demonstrate that CQAs have a wide range of biological activities, such as antioxidation, antibacterial, antiparasitic, neuroprotective, anti-inflammatory, anticancer, antiviral, and antidiabetic effects. Up to date, some meaningful progresses on the biosynthesis and total synthesis of CQAs have also been made. Therefore, it is necessary to comprehensively summarize the structure, biological activity, biosynthesis, and chemical synthesis of CQAs. This review provides extensive coverage of naturally occurring CQAs discovered from 1990 until 2020. Modern isolation techniques, chemical data (including structure, biosynthesis, and total synthesis), and bioactivity are summarized. This would be helpful for further research of CQAs as potential pharmaceutical agents.

Metabolomics Reveals Distinct Metabolites between Lonicera japonica and Lonicera macranthoides Based on GC-MS

Lonicera japonica Thunb. (LJ) and Lonicera macranthoides Hand. -Mazz. (LM) have been widely used in Chinese medicine for thousands of years. Although the morphological characteristics of LJ and LM are quite similar, there are significant distinctions of medicinal ingredients (mainly the secondary metabolites) and clinical indications between them. However, the in-depth differences of primary metabolites have not thoroughly been studied yet. Therefore, gas chromatography-mass spectrometry- (GC-MS-) based metabolomics method combined with chemometric methods were performed to analyze the distinction in this study. The results showed that LJ and LM were obviously classified into two groups. 10 metabolites were obtained as biomarkers on account of their p values, pcorr values, and differing variable importance in projection (VIP) values. Metabolic pathway analysis showed that the galactose metabolism and starch and sucrose metabolism gathered as potential pathways caused these extraordinary differences of primary metabolites between LJ and LM. Further, we found that the differences of main medicinal ingredients between LJ and LM could be interpreted from these metabolites according to the analysis of mainly related pathways. The metabolites involved in the starch and sucrose metabolism presented upregulated in LJ, while almost all metabolites in the galactose metabolism, the TCA cycle, and the phenolic acid part of phenylpropanoid metabolism were downregulated in LJ. Therefore, the energy stored in the starch and sucrose metabolism may be saved to produce flavonoid, which could be the reason that the level of flavonoid of phenylpropanoid metabolism is higher in LJ compared to LM. Consequently, this study presented an effective tool for quality evaluation of LJ and LM and laid a foundation for further studies of the metabolic mechanisms and high-quality manufacturing of them.

Caffeoylquinic Acids with Potential Biological Activity from Plant In vitro Cultures as Alternative Sources of Valuable Natural Products

BACKGROUND

For a long time, the researchers have been looking for new efficient methods to enhance production and obtain valuable plant secondary metabolites, which would contribute to the protection of the natural environment through the preservation of various plant species, often rare and endangered. These possibilities offer plant in vitro cultures which can be performed under strictly-controlled conditions, regardless of the season or climate and environmental factors. Biotechnological methods are promising strategies for obtaining the valuable plant secondary metabolites with various classes of chemical compounds including caffeoylquinic acids (CQAs) and their derivatives. CQAs have been found in many plant species which are components in the daily diet and exhibit a wide spectrum of biological activities, including antioxidant, immunomodulatory, antihypertensive, analgesic, anti-inflammatory, hepato- and neuroprotective, anti-hyperglycemic, anticancer, antiviral and antimicrobial activities. They have also been found to offer protection against Alzheimer's disease, and play a role in weight reduction and lipid metabolism control, as well as modulating the activity of glucose-6-phosphatase involved in glucose metabolism.

METHODS

This work presents the review of the recent advances in use in vitro cultures of various plant species for the alternative system to the production of CQAs and their derivatives. Production of the secondary metabolites in in vitro culture is usually performed with cell suspension or organ cultures, such as shoots and adventitious or transformed roots. To achieve high production of valuable secondary metabolites in in vitro cultures, the optimization of the culture condition is necessary with respect to both biomass accumulation and metabolite content. The optimization of the culture conditions can be achieved by choosing the type of medium, growth regulators or growth conditions, selection of high-productivity lines or culture period, supplementation of the culture medium with precursors or elicitor treatments. Cultivation for large-scale in bioreactors and genetic engineering: Agrobacterium rhizogenes transformation and expression improvement of transcriptional factor or genes involved in the secondary metabolite production pathway are also efficient strategies for enhancement of the valuable secondary metabolites.

RESULTS

Many studies have been reported to obtain highly productive plant in vitro cultures with respect to CQAs. Among these valuable secondary metabolites, the most abundant compound accumulated in in vitro cultures was 5-CQA (chlorogenic acid). Highly productive cultures with respect to this phenolic acid were Leonurus sibiricus AtPAP1 transgenic roots, Lonicera macranthoides and Eucomia ulmoides cell suspension cultures which accumulated above 20 mg g-1 DW 5-CQA. It is known that di- and triCQAs are less common in plants than monoCQAs, but it was also possible to obtain them by biotechnological methods.

CONCLUSION

The results indicate that the various in vitro cultures of different plant species can be a profitable approach for the production of CQAs. In particular, an efficient production of these valuable compounds is possible by Lonicera macranthoides and Eucomia ulmoides cell suspension cultures, Leonurus sibiricus transformed roots and AtPAP1 transgenic roots, Echinacea angustifolia adventitious shoots, Rhaponticum carthamoides transformed plants, Lavandula viridis shoots, Sausera involucrata cell suspension and Cichorium intybus transformed roots.

Consumption of Chlorogenic Acids through Coffee and Health Implications

Chlorogenic acids (CGA) are the main antioxidant compounds in the Western diet, due to their high concentrations in coffee associated with the high consumption of the beverage. Until about 10 years ago, like many other phenolic compounds, CGA were thought to be poorly absorbed in the human digestive system. Along the years, large amounts of information on the absorption and metabolism of these compounds have been unveiled, and today, it is known that, on average, about one third of the consumed CGA from coffee is absorbed in the human gastrointestinal tract, although large inter-individual variation exists. Considering results from in vitro animal and human studies, it is possible to conclude that the antioxidant and anti-inflammatory effects of coffee CGA are responsible for, at least to a certain extent, the association between coffee consumption and lower incidence of various degenerative and non-degenerative diseases, in addition to higher longevity.

Potential nutraceutical and food additive properties and risks of coffee: a comprehensive overview

Coffee is a composite mixture of more than a thousand diverse phytochemicals like alkaloids, phenolic compounds, vitamins, carbohydrates, lipids, minerals and nitrogenous compounds. Coffee has multifunctional properties as a food additive and nutraceutical. As a nutraceutical, coffee has anti-inflammatory, anti-oxidant, antidyslipidemic, anti-obesity, type-2 diabetes mellitus (DM), and cardiovascular diseases (CVD), which can serve for the treatment and prevention of metabolic syndrome and associated disorders. On the other hand, as a food additive, coffee has antimicrobial activity against a wide range of microorganisms, inhibits lipid peroxidation (LPO), and can function as a prebiotic. The outcomes of different studies also revealed that coffee intake may reduce the incidence of numerous chronic diseases, like liver disease, mental health, and it also overcomes the all-cause mortality, and suicidal risks. In some studies, high intake of coffee is linked to increase CVD risk factors, like cholesterol, plasma homocysteine and blood pressure (BP). There is also a little evidence that associated the coffee consumption with increased risk of lung tumors in smokers. Among adults who consume the moderate amount of coffee, there is slight indication of health hazards with strong indicators of health benefits. Moreover, existing literature suggests that it may be cautious for pregnant women to eliminate the chances of miscarriages and impaired fetal growth. The primary purpose of this narrative review is to provide an overview of the findings of the positive impacts and risks of coffee consumption on human health. In conclusion, to date, the best available evidence from research indicates that drinking coffee up to 3-4 cups/day provides health benefits for most people.

Identifying anti-HSV compounds from unrelated plants using NMR and LC-MS metabolomic analysis

INTRODUCTION

Plants have been used to treat various ailments and diseases, including viral infections. Often activity is reported after screening plants traditionally used, without identifying the active principles.

OBJECTIVES

This study investigated the use of metabolomics to identify common compound groups or compounds from unrelated plants, but with similar reported biological activity. Plants with anti-viral activities against Herpes Simplex Virus (HSV), Cytomegalovirus (CMV) and Human Immunodeficiency Virus (HIV) were collected and analysed. A few non-active plants, with no reported anti-viral activity were included as control samples.

METHODS

1H-NMR and LC-MS metabolomic analysis were conducted, to determine the chemical similarity between plants with similar activity using SIMCA and XCMS online.

RESULTS

Plants with anti-HSV, anti-HIV and anti-CMV activity, presented specific clusters, with the non-active samples separating from the active samples. The anti-HSV group presented a clear contribution plot and chlorogenic acid was identified by NMR. LC-MS metabolomic analysis confirmed the NMR results and furthermore identified several chlorogenic acid isomers including the main substructures of chlorogenic acids.

CONCLUSION

Metabolomic analysis on unrelated plants with similar activity can be used to identify the active compound groups or compounds, thereby eliminating the need for screening of plants to determine biological activity, additionally providing information on possible active principles. The two analytical methods identified chlorogenic acids and its building blocks as common and important compounds within plants with anti-HSV activity. Intensified research on plants containing chlorogenic acids should be the focus of future research for development of accessible anti-HSV treatments.

Metabolomics-guided investigations of unintended effects of the expression of the hydroxycinnamoyl quinate hydroxycinnamoyltransferase (hqt1) gene from Cynara cardunculus var. scolymus in Nicotiana tabacum cell cultures

Chlorogenic acids (CGAs) are phenolic compounds biosynthesized in the phenylpropanoid pathway, with hydroxycinnamoyl quinate hydroxycinnamoyltransferase (HQT) as the key enzyme. Variation of CGAs has been noted in different plants, with globe artichoke (Cynara cardunculus var. scolymus L.) producing high amounts and a diverse spectrum of CGAs in its leaves. In the current study, the effect of overexpression of the hqt1 transgene from globe artichoke in tobacco was evaluated at the metabolome level. Here, metabolomic approaches based on ultra-high performance liquid chromatography coupled to mass spectrometry, together with chemometric models such as principal component analysis and orthogonal partial least square discriminant analysis, were employed to evaluate altered metabolic changes due to hqt1 overexpression. CGA profiles (caffeoylquinic acids: 3-CQA, 4-CQA and 5-CQA; p-coumaroylquinic acids: 4-pCoQA and 5-pCoQA; and 4,5-di-caffeoylquinic acid) of transgenic tobacco cell cultures were detected at lower concentrations than in the wild type. Interestingly, the cells were found to rather accumulate, as an unintended effect, abscisic acid - and benzoic acid derivatives. The results suggest that insertion of hqt1 in tobacco, and overexpression in undifferentiated cells, led to rechannelling of the phenylpropanoid pathway to accumulate benzoic acids. These findings proved to be contrary to the results shown elsewhere in leaf tissues, thus indicating differential metabolic control and regulation in the undifferentiated cell culture system.

Anti-HIV activity of southern African plants: Current developments, phytochemistry and future research

ETHNOPHARMACOLOGICAL RELEVANCE

The African continent is home to a large number of higher plant species used over centuries for many applications, which include treating and managing diseases such as HIV. Due to the overwhelming prevalence and incidence rates of HIV, especially in sub-Saharan Africa, it is necessary to develop new and affordable treatments.

AIM OF THE STUDY

The article provides an extensive overview of the status on investigation of plants from the southern African region with ethnobotanical use for treating HIV or HIV-related symptoms, or the management of HIV. The review also provide an account of the in vitro assays, anti-viral activity and phytochemistry of these plants.

MATERIALS AND METHODS

Peer-reviewed articles investigating plants with ethnobotanical information for the treatment or management of HIV or HIV-related symptoms from the southern African region were acquired from Science Direct, PubMed central and Google Scholar. The selection criteria was that (1) plants should have a record of traditional/popular use for infectious or viral diseases, HIV treatment or symptoms similar to HIV infection, (2) if not traditionally/popularly used, plants should be closely related to plants with popular use and HIV activity identified by means of in vitro assays, (3) plants should have been identified scientifically, (4) should be native to southern African region and (5) anti-HIV activity should be within acceptable ranges.

RESULTS

Many plants in Africa and specifically the southern African region have been used for the treatment of HIV or HIV related symptoms and have been investigated suing various in vitro techniques. In vitro assays using HIV enzymes such as reverse transcriptase (RT), integrase (IN) and protease (PR), proteins or cell-based assays have been employed to validate the use of these plants with occasional indication of the selectivity index (SI) or therapeutic index (TI), with only one study, that progressed to in vivo testing. The compounds identified from plants from southern Africa is similar to compounds identified from other regions of the world, and the compounds have been divided into three groups namely (1) flavonoids and flavonoid glycosides, (2) terpenoids and terpenoid glycosides and (3) phenolic acids and their conjugated forms.

CONCLUSIONS

An investigation of the plants from southern Africa with ethnobotanical use for the treatment of HIV, management of HIV or HIV-related symptoms, therefore provide a very good analysis of the major assays employed and the anti-viral compounds and compound groups identified. The similarity in identified anti-viral compounds worldwide should support the progression from in vitro studies to in vivo testing in development of affordable and effective anti-HIV agents for countries with high infection and mortality rates due to HIV/AIDS.

Regulation of chlorogenic acid biosynthesis by hydroxycinnamoyl CoA quinate hydroxycinnamoyl transferase in Lonicera japonica

For many centuries, Lonicera japonica has been used as an effective herb for the treatment of inflammation and swelling because of the presence of bioactive components such as chlorogenic acid (CGA). To clarify the relationship between L. japonica hydroxycinnamoyl CoA quinate hydroxycinnamoyl transferase (HQT) gene expression and CGA content, an HQT eukaryotic expression system was constructed using Gateway cloning. L. japonica callus transformed with HQT was obtained using Agrobacterium tumefaciens-mediated transformation. We found a positive correlation between CGA content, determined by High-Performance Liquid Chromatography (HPLC), and the expression of HQT, analyzed by semi-quantitative RT-PCR. This study demonstrates that the HQT gene positively regulates CGA synthesis and lays the foundation for further study into enhancing efficacious components of medicinal plants.

Chlorogenic acid (CGA): A pharmacological review and call for further research

Phenolic acids have recently gained substantial attention due to their various practical, biological and pharmacological effects. Chlorogenic Acid (CGA, 3-CQA) is a most abundant isomer among caffeoylquinic acid isomers (3-, 4-, and 5-CQA), that currently known as 5-CQA as per guidelines of IUPAC. It is one of the most available acids among phenolic acid compounds which can be naturally found in green coffee extracts and tea. CGA is an important and biologically active dietary polyphenol, playing several important and therapeutic roles such as antioxidant activity, antibacterial, hepatoprotective, cardioprotective, anti-inflammatory, antipyretic, neuroprotective, anti-obesity, antiviral, anti-microbial, anti-hypertension, free radicals scavenger and a central nervous system (CNS) stimulator. In addition, it has been found that CGA could modulate lipid metabolism and glucose in both genetically and healthy metabolic related disorders. It is speculated that CGA can perform crucial roles in lipid and glucose metabolism regulation and thus help to treat many disorders such as hepatic steatosis, cardiovascular disease, diabetes, and obesity as well. Furthermore, this phenolic acid (CGA) causes hepatoprotective effects by protecting animals from chemical or lipopolysaccharide-induced injuries. The hypocholesterolemic influence of CGA can result from the altered metabolism of nutrients, including amino acids, glucose and fatty acids (FA). The purpose of this review was to broaden the scope of knowledge of researchers to conduct more studies on this subject to both unveil and optimize its biological and pharmacological effects. As a result, CGA may be practically used as a natural safeguard food additive to replace the synthetic antibiotics and thereby reduce the medicinal cost.

Antiviral activity of chlorogenic acid against influenza A (H1N1/H3N2) virus and its inhibition of neuraminidase

Lonicera japonica Thunb, rich in chlorogenic acid (CHA), is used for viral upper respiratory tract infection treatment caused by influenza virus, parainfluenza virus, and respiratory syncytial virus, ect in China. It was reported that CHA reduced serum hepatitis B virus level and death rate of influenza virus-infected mice. However, the underlying mechanisms of CHA against the influenza A virus have not been fully elucidated. Here, the antiviral effects and potential mechanisms of CHA against influenza A virus were investigated. CHA revealed inhibitory against A/PuertoRico/8/1934(H1N1) (EC₅₀ = 44.87 μM), A/Beijing/32/92(H3N2) (EC₅₀ = 62.33 μM), and oseltamivir-resistant strains. Time-course analysis showed CHA inhibited influenza virus during the late stage of infectious cycle. Indirect immunofluorescence assay indicated CHA down-regulated the NP protein expression. The inhibition of neuraminidase activity confirmed CHA blocked release of newly formed virus particles from infected cells. Intravenous injection of 100 mg/kg/d CHA possessed effective antiviral activity in mice, conferring 60% and 50% protection from death against H1N1 and H3N2, reducing virus titres and alleviating inflammation in the lungs effectively. These results demonstrate that CHA acts as a neuraminidase blocker to inhibit influenza A virus both in cellular and animal models. Thus, CHA has potential utility in the treatment of the influenza virus infection.

The Effect of Geometrical Isomerism of 3,5-Dicaffeoylquinic Acid on Its Binding Affinity to HIV-Integrase Enzyme: A Molecular Docking Study

A potent plant-derived HIV-1 inhibitor, 3,5-dicaffeoylquinic acid (diCQA), has been shown to undergo isomerisation upon UV exposure where the naturally occurring 3 ^trans ,5 ^trans -diCQA isomer gives rise to the 3 ^cis ,5 ^trans -diCQA, 3 ^trans ,5 ^cis -diCQA, and 3 ^cis ,5 ^cis -diCQA isomers. In this study, inhibition of HIV-1 INT by UV-induced isomers was investigated using molecular docking methods. Here, density functional theory (DFT) models were used for geometry optimization of the 3,5-diCQA isomers. The YASARA and Autodock VINA software packages were then used to determine the binding interactions between the HIV-1 INT catalytic domain and the 3,5-diCQA isomers and the Discovery Studio suite was used to visualise the interactions between the isomers and the protein. The geometrical isomers of 3,5-diCQA were all found to bind to the catalytic core domain of the INT enzyme. Moreover, the cis geometrical isomers were found to interact with the metal cofactor of HIV-1INT, a phenomenon which has been linked to antiviral potency. Furthermore, the 3 ^trans ,5 ^cis -diCQA isomer was also found to interact with both LYS156 and LYS159 which are important residues for viral DNA integration. The differences in binding modes of these naturally coexisting isomers may allow wider synergistic activity which may be beneficial in comparison to the activities of each individual isomer.

Preferential alkali metal adduct formation by cis geometrical isomers of dicaffeoylquinic acids allows for efficient discrimination from their trans isomers during ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

RATIONALE

Caffeoylquinic acid (CQA) derivatives are a group of structurally diverse phytochemicals that have attracted attention due to their many health benefits. The structural diversity of these molecules is due in part to the presence of regio- and geometrical isomerism. This structural diversity hampers the accurate annotation of these molecules in plant extracts. Mass spectrometry (MS) is successfully used to differentiate between the different regioisomers of the CQA derivatives; however, the accurate discrimination of the geometrical isomers of these molecules has proven to be an elusive task.

METHODS

UV-irradiated methanolic solutions of diCQA were analyzed using an ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOFMS) method in negative ionisation mode. An in-source collision-induced dissociation (ISCID) method was optimized by varying both the capillary and cone voltages to achieve differential fragmentation patterns between UV-generated geometrical isomers of the diCQAs during MS analyses.

RESULTS

Changes in the capillary voltage did not cause a significant difference to the fragmentation patterns of the four geometrical isomers, while changes in the cone voltage resulted in significant differences in the fragmentation patterns. The results also show, for the first time, the preferential formation of alkali metal (Li(+), Na(+) and K(+)) adducts by the cis geometrical isomers of diCQAs, compared to their trans counterparts.

CONCLUSIONS

Optimized QTOFMS-based methods may be used to differentiate the geometrical isomers of diCQAs. Finally, additives such as metal salts to induce adduct formation can be applied as an alternative method to differentiate closely related isomers which could have been difficult to differentiate under normal MS settings.

Identification of anti-HIV active dicaffeoylquinic- and tricaffeoylquinic acids in Helichrysum populifolium by NMR-based metabolomic guided fractionation

South Africa being home to more than 35% of the world's Helichrysum species (c.a. 244) of which many are used in traditional medicine, is seen potentially as a significant resource in the search of new anti-HIV chemical entities. It was established that five of the 30 Helichrysum species selected for this study had significant anti-HIV activity ranging between 12 and 21 μg/mL (IC50) by using an in-house developed DeCIPhR method on a full virus model. Subsequent toxicity tests also revealed little or no toxicity for these active extracts. With the use of NMR-based metabolomics, the search for common chemical characteristics within the plant extract was conducted, which resulted in specific chemical shift areas identified that could be linked to the anti-HIV activity of the extracts. The NMR chemical shifts associated with the activity were identified to be 2.56-3.08 ppm, 5.24-6.28 ppm, 6.44-7.04 ppm and 7.24-8.04 ppm. This activity profile was then used to guide the fractionation process by narrowing down and focusing the fractionation and purification processes to speed up the putative identification of five compounds with anti-HIV activity in the most active species, Helichrysum populifolium. The anti-HIV compounds identified for the first time from H. populifolium were three dicaffeoylquinic acid derivatives, i.e. 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid as well as two tricaffeoylquinic acid derivatives i.e. 1,3,5-tricaffeoylquinic acid and either 5-malonyl-1,3,4-tricaffeoylquinic or 3-malonyl-1,4,5-tricaffeoylquinic acid, with the latter being identified for the first time in the genus.

Long-term cultured hairy roots of chicory-a rich source of hydroxycinnamates and 8-deoxylactucin glucoside

A 12-year-old hairy root culture of Cichorium intybus L., a callus culture of the plant as well as roots and leaves of a wild plant of chicory, and roots of two C. intybus L. var. sativum cultivars were examined in respect of their hydroxycinnamate and sesquiterpene lactone compositions and contents. Total phenolics and diphenylpicrylhydrazyl radical scavenging activity of the examined plant tissues were also analyzed. The most active in radical scavenging were extracts from the hairy roots and leaves of chicory. 3,5-Dicaffeoylquinic acid was the major antioxidant present in the hairy roots. Its content in the root biomass reached 5.5 %, calculated on a dry weight basis. 8-Deoxylactucin glucoside (crepidiaside A) was the major sesquiterpene lactone in the hairy roots. Its content reached 1.4 %, calculated on a dry weight basis, and was nearly two orders of magnitude higher than that in the roots of wild chicory plant. The glucosidic derivative of 8-deoxylactucin constituted over 85 % of the total sesquiterpene lactone content in the long-term cultured hairy roots of chicory. Aglycone of this compound was reported to possess anti-inflammatory activity. The qualitative and quantitative analyses of hydroxycinnamates in callus and hairy root cultures of C. intybus were undertaken for the first time.

Chlorogenic acid inhibits the replication and viability of enterovirus 71 in vitro

Enterovirus 71 (EV71) is an etiology for a number of diseases in humans. Traditional Chinese herbs have been reported to be effective for treating EV71 infection. However, there is no report about the antiviral effects of CHA against EV71. In this study, plaque reduction assay demonstrated that the inhibitory concentration 50% (IC50) of CHA on EV71 replication is 6.3 µg/ml. When both CHA (20 µg/ml) and EV71 were added, or added post-infection at different time points, CHA was able to effectively inhibit EV71 replication between 0 and 10 h. In addition, CHA inhibited EV71 2A transcription and translation in EV71-infected RD cells, but did not affect VP1, 3C, and 3D expression. Furthermore, CHA inhibited secretions of IL-6, TNF-α, IFN-γ and MCP-1 in EV71-infected RD cells. Altogether, these results revealed that CHA may have antiviral properties for treating EV71 infection.

Inhibition of platelet aggregation by chlorogenic acid via cAMP and cGMP-dependent manner

In this study, we investigated the effect of chlorogenic acid, a phenolic acid, on collagen (10 μg/ml)-stimulated platelet aggregation. Chlorogenic acid dose-dependently inhibited collagen-induced platelet aggregation, and suppressed the production of thromboxane A2 (TXA2), an intracellular Ca-agonist as an aggregation-inducing autacoidal molecule, which was associated with the strong inhibition of cyclooxygenase (COX)-1 in platelet microsomes having cytochrome c reductase activity. In addition, chlorogenic acid increased significantly the formation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), intracellular Ca-antagonists as aggregation-inhibiting molecules. These results suggest that chlorogenic acid has antiplatelet activity through the reduction of TXA2 and the increase of cAMP and cGMP levels. Therefore, our data demonstrate that chlorogenic acid is a potent inhibitor of collagen-stimulated platelet aggregation, and may be a crucial tool for a negative regulator during platelet activation in thrombotic diseases.

Content of antioxidative caffeoylquinic acid derivatives in field-grown Ligularia fischeri (Ledeb.) Turcz and responses to sunlight

Ligularia fischeri (Ledeb.) Turcz, a commercial leafy vegetable, contains caffeoylquinic acid derivatives (CQAs) as major phenolic constituents. The HPLC chromatograms of leaf extracts collected from different areas in Korea showed a significant variation in CQA amount, and two tri-O-caffeoylquinic acids (triCQAs) were purified and structurally identified by NMR and MS from this plant. Radical scavenging activities among CQAs were found to be increased in proportion to the number of caffeoyl groups. Since this plant prefers damp and shady growth conditions, the effects of sunlight were investigated by growing plantlets in sunlight and shade for four weeks. Greater leaf thickness and higher phenolic contents were found for leaves grown in sunlight than in shade. Four major CQAs-5-mono-O-caffeoylquinic acid (5-monoCQA), and 3,4-, 3,5-, and 4,5-di-O-caffeoylquinic acid (diCQA)-were induced by solar irradiation, whereas the content of these compounds decreased steadily in shade leaves. The leaves of L. fischeri clearly showed adaptation responses to sunlight, and these characteristics can be exploited for cultivation of this plant for potential use as a nutraceutical and functional food.

Anti-hepatitis B virus activity of chlorogenic acid, quinic acid and caffeic acid in vivo and in vitro

Chlorogenic acid and its related compounds are abundant plant polyphenols that have a diverse antiviral activity. In this study, HepG2.2.15 cells and duck hepatitis B virus infection model were used as in vitro and in vivo models to evaluate their anti-HBV activity. In the cell model, all the three compounds inhibited HBV-DNA replication as well as HBsAg production. Chlorogenic acid and caffeic acid also reduced serum DHBV level in DHBV-infected duckling model. Moreover, the anti-HBV activity of crude extracts of coffee beans, which have a high content of chlorogenic acid, was studied. Both the extracts of regular coffee and that of decaffeinated coffee showed inhibitory effect on HBV replication.

Identification of hydroxycinnamoylquinic acids of arnica flowers and burdock roots using a standardized LC-DAD-ESI/MS profiling method

A screening method using LC-DAD-ESI/MS was developed for the identification of common hydroxycinnamoylquinic acids based on direct comparison with standards. A complete standard set for mono-, di-, and tricaffeoylquinic isomers was assembled from commercially available standards, positively identified compounds in common plants (artichokes, asparagus, coffee bean, honeysuckle flowers, sweet potato, and Vernonia amygdalina leaves) and chemically modified standards. Four C18 reversed phase columns were tested using the standardized profiling method (based on LC-DAD-ESI/MS) for 30 phenolic compounds, and their elution order and retention times were evaluated. Using only two columns under standardized LC condition and the collected phenolic compound database, it was possible to separate all of the hydroxycinnamoylquinic acid conjugates and to identify 28 and 18 hydroxycinnamoylquinic acids in arnica flowers (Arnica montana L.) and burdock roots (Arctium lappa L.), respectively. Of these, 22 are reported for the first time.

AtMYB12 regulates caffeoyl quinic acid and flavonol synthesis in tomato: expression in fruit results in very high levels of both types of polyphenol

Plant polyphenolics exhibit a broad spectrum of health-promoting effects when consumed as part of the diet, and there is considerable interest in enhancing the levels of these bioactive molecules in plants used as foods. AtMYB12 was originally identified as a flavonol-specific transcriptional activator in Arabidopsis thaliana, and this has been confirmed by ectopic expression in tobacco. AtMYB12 is able to induce the expression of additional target genes in tobacco, leading to the accumulation of very high levels of flavonols. When expressed in a tissue-specific manner in tomato, AtMYB12 activates the caffeoyl quinic acid biosynthetic pathway, in addition to the flavonol biosynthetic pathway, an activity which probably mirrors that of the orthologous MYB12-like protein in tomato. As a result of its broad specificity for transcriptional activation in tomato, AtMYB12 can be used to produce fruit with extremely high levels of multiple polyphenolic anti-oxidants. Our data indicate that transcription factors may have different specificities for target genes in different plants, which is of significance when designing strategies to improve metabolite accumulation and the anti-oxidant capacity of foods.