Quantification and antioxidant and anti-HCV activities of the constituents from the inflorescences of Scabiosa comosa and S. tschilliensis

Pharmacological profile of dicaffeoylquinic acids and their role in the treatment of respiratory diseases

Dicaffeoylquinic acids (DCQAs) are polyphenolic compounds found in various medicinal plants such as Echinacea species and Hedera helix, whose multi-constituent extracts are used worldwide to treat respiratory diseases. Besides triterpenes, saponins, alkamides, and other constituents, DCQAs are an important group of substances for the pharmacological activity of plant-derived extracts. Therefore, the pharmacological properties of DCQAs have been studied over the last decades, suggesting antioxidative, anti-inflammatory, antimicrobial, hypoglycaemic, cardiovascular protective, neuroprotective, and hepatoprotective effects. However, the beneficial pharmacological profile of DCQAs has not yet been linked to their use in treating respiratory diseases such as acute or even chronic bronchitis. The aim of this review was to assess the potential of DCQAs for respiratory indications based on published in vitro and in vivo pharmacological and pre-clinical data, with particular focus on antioxidative, anti-inflammatory, and respiratory-related effects such as antitussive or antispasmodic properties. A respective literature search revealed a large number of publications on the six DCQA isoforms. Based on this search, a focus was placed on 1,3-, 3,4-, 3,5-, and 4,5-DCQA, as the publications focused mainly on these isomers. Based on the available pre-clinical data, DCQAs trigger cellular mechanisms that are important in the treatment of respiratory diseases such as decreasing NF-κB activation, reducing oxidative stress, or activating the Nrf2 pathway. Taken together, these data suggest an essential role for DCQAs within herbal medicines used for the treatment of respiratory diseases and highlights the need for the identifications of DCQAs as lead substances within such extracts.

Investigation of Phytochemical, Antioxidant and Antidiabetic Potentials of Scabiosa L. (Caprifoliaceae) Species with Chemometric Methods

In this research, the total phenolic and flavonoid amounts, phenolic compositions, in vitro antioxidant, antibacterial and antidiabetic properties of the methanol extracts obtained from Scabiosa L. (Caprifoliaceae) species distributed in the flora of Türkiye were investigated using chemometric methods. For this purpose, principal component (PCA) and agglomerative hierarchical clustering analysis were performed as chemometric methods. Chlorogenic acid, quinic acid and cyranoside were determined in the extracts. According to chemometric analysis, S. columbaria subsp. ochroleuca var. ochroleuca and S. triniifolia species were found to be valuable in terms of methanol extract yields, total phenolic and flavonoid contents, antioxidant and antidiabetic activities while S. columbaria subsp. ochroleuca var. webbiana species were found to be valuable in terms of phenolic composition. The methanol extracts of Scabiosa species showed high antioxidant activity, with high phenolic and flavonoid contents. Among the tested 13 bacteria, Scabiosa extracts showed only low activity against Klebsiella pneumoniae, Streptococcus pneumoniae and Pseudomonas aeruginosa. The extracts showed high α-amylase and α-glucosidase inhibitory activity. The results show that Scabiosa methanol extracts may be a source of alternative antioxidants that may be beneficial in slowing or preventing the progression of various oxidative stress-related diseases.

Medicinal plant molecules against hepatitis C virus: Current status and future prospect

Hepatitis C virus (HCV), a global malady, causes acute and chronic hepatitis leading to permanent liver damage, hepatocellular carcinoma, and death. Modern anti-HCV therapies are efficient, but mostly inaccessible for residents of underdeveloped regions. To innovate more effective treatments at affordable cost, medicinal plant-based products need to be explored. The aim of this article is to review plant constituents in the light of putative anti-HCV mechanisms of action, and discuss existing problems, challenges, and future directions for their potential application in therapeutic settings. One hundred sixty literatures were collected by using appropriate search strings via scientific search engines: Google Scholar, PubMed, ScienceDirect, and Scopus. Bibliography was prepared using Mendeley desktop software. We found a substantial number of plants that were reported to inhibit different stages of HCV life cycle. Traditional medicinal plants such as Phyllanthus amarus Schumach. and Thonn., Eclipta alba (L.) Hassk., and Acacia nilotica (L.) Delile exhibited strong anti-HCV activities. Again, several phytochemicals such as epigallocatechin-3-gallate, honokilol, punicalagin, and quercetin have shown broad-spectrum anti-HCV effect. We have presented promising phytochemicals like silymarin, curcumin, glycyrrhizin, and camptothecin for nanoparticle-based hepatocyte-targeted drug delivery. Nevertheless, only a few animal studies have been performed to validate the anti-HCV effect of these plant products. Again, insufficient clinical evaluation of the safety and effectiveness of herbal medications remain a problem. Selected plants products could be developed as novel therapeutics for HCV patients only after scrupulous evaluation of their safety and efficacy in a clinical set-up.

Dipsacus and Scabiosa Species-The Source of Specialized Metabolites with High Biological Relevance: A Review

The genera Dipsacus L. and Scabiosa L. of the Caprifoliaceae family are widely distributed in Europe, Asia, and Africa. This work reviews the available literature on the phytochemical profiles, ethnomedicinal uses, and biological activities of the most popular species. These plants are rich sources of many valuable specialized metabolites with beneficial medicinal properties, such as triterpenoid derivatives, iridoids, phenolic acids, and flavonoids. They are also sources of essential oils. The genus Dipsacus has been used for centuries in Chinese and Korean folk medicines to treat bone (osteoporosis) and joint problems (rheumatic arthritis). The Korean Herbal Pharmacopoeia and Chinese Pharmacopoeia include Dipsaci radix, the dried roots of D. asperoides C.Y.Cheng & T.M.Ai. In addition, S. comosa Fisch. ex Roem & Schult. and S. tschiliiensis Grunning are used in traditional Mongolian medicine to treat liver diseases. The current scientific literature data indicate that these plants and their constituents have various biological properties, including inter alia antiarthritic, anti-neurodegenerative, anti-inflammatory, antioxidant, anticancer, and antimicrobial activities; they have also been found to strengthen tendon and bone tissue and protect the liver, heart, and kidney. The essential oils possess antibacterial, antifungal, and insecticidal properties. This paper reviews the key biological values of Dipsacus and Scabiosa species, as identified by in vitro and in vivo studies, and presents their potential pharmacological applications.

Scabiosa atropurpurea: A rich source of iridoids with α-glucosidase inhibitory activity evaluated by in vitro and in silico studies

Scabiosa atropurpurea L. subsp. maritima (L.) Arc. (Caprifoliaceae) is a plant widely distributed in the Mediterranean region and represented by 32 taxa in the flora of Turkey. In the present study, an in-depth phytochemical investigation of S. atropurpurea methanol extract of the whole plant was carried out using a combination of LC-ESI-FT-MS and NMR analysis. This approach allowed the isolation and structural elucidation of 28 compounds: 17 iridoids, 7 flavonoids, and 4 phenolic acids. Among these compounds, three previously unreported iridoids named secologanin-methyl-hemiacetal, atropurpurin A, and atropurpurin B were identified. The methanol extract of S. atropurpurea was assayed for its antioxidant and antihyperglycemic activity, showing a potent α-glucosidase inhibitory activity (IC₅₀ = 100 μg/mL), higher than that exerted by acarbose (IC₅₀ = 196 μg/mL), used as the positive control. Thus, the most abundant iridoids were selected to be tested for their antihyperglycemic activity, and molecular docking experiments were carried out to assess the possibility for selected compounds to form complexes with α-glucosidase enzyme active site.

Methyl-β-D-glucopyranoside From Scabiosa comosa as a Quorum-Sensing Inhibitor

Quorum sensing (QS) is an important microbial signaling system that controls the expression of many virulence genes. Combination treatment with QS inhibitors and antibiotics may be the new treatment option for infectious diseases in the future. Therefore, there is an increasing need to discover anti-QS compounds to prevent antimicrobial resistance. We isolated methyl-β-D-glucopyranoside from Scabiosa comosa and found that it exerts an anti-QS activity against Chromobacterium violaceum CV026 without exhibiting any antimicrobial activity.

Potential Mechanisms Involved in the Protective Effect of Dicaffeoylquinic Acids from Artemisia annua L. Leaves against Diabetes and Its Complications

Diabetes mellitus is a chronic disease affecting the globe and its incidence is increasing pandemically. The use of plant-derived natural products for diabetes management is of great interest. Polar fraction of Artemisia annua L. leaves has shown antidiabetic activity in vivo. In the present study, three major compounds were isolated from this polar fraction; namely, 3,5-dicaffeoylquinic acid (1); 4,5-dicaffeoylquinic acid (2), and 3,4- dicaffeoylquinic acid methyl ester (3), using VLC-RP-18 and HPLC techniques. The potential protective effects of these compounds against diabetes and its complications were investigated by employing various in vitro enzyme inhibition assays. Furthermore, their antioxidant and wound healing effectiveness were evaluated. Results declared that these dicaffeoylquinic acids greatly inhibited DPPIV enzyme while moderately inhibited α-glucosidase enzyme, where compounds 1 and 3 displayed the most prominent effects. In addition, compound 3 showed pronounced inhibition of α-amylase enzyme. Moreover, these compounds markedly inhibited aldose reductase enzyme and exerted powerful antioxidant effects, among which compound 3 exhibited the highest activity implying a notable potentiality in impeding diabetes complications. Interestingly, compounds 2 and 3 moderately accelerated scratch wound healing. Our findings suggest that these dicaffeoylquinic acids can be promising therapeutic agents for managing diabetes and its complications.

Chemical compositions by using LC-MS/MS and GC-MS and antioxidant activities of methanolic extracts from leaf and flower parts of Scabiosa columbaria subsp. columbaria var. columbaria L

The members of the Scabiosa genus are one of the traditional medicinal plants used in the treatment of many diseases, in particular the treatment of scabies. In this study, it was aimed to determine antioxidant activities and chemical composition of methanolic extracts of leaves and flowers of Scabiosa columbaria subsp. columbaria var. columbaria. The phenolic contents of both parts of the plant were analyzed by LC-MS/MS. A total of 6 phenolic compounds were determined and chlorogenic acid was the major compound in both flower and leaf parts of the plants, with 5936.052 µg/g and 8021.666 µg/g, respectively. 6 different methods were used to determine the antioxidant activity of the plant parts. Both leaf and flower parts of the plant showed high antioxidant activity in all tested methods and the antioxidant activity values of the leaf part were measured higher than those of the flower part for four tests. The methanol extracts of the plant parts was analyzed with GC-MS and number of the essential oil compounds in the leaf and flower parts were determined as 17 and 13, respectively. Linalool compound was also found to be common in both parts of the plant. The major compounds of the essential oils were identified as 4-Octadecenal (30.01%) in the flower and carvone (35.44%) in the leaf. In addition, terpene derivatives was determined as 90.32% of the highest essential oil group in the leaf, while this value was determined as 1.42% in the flower. For the flower, aromatics were determined as the main component group with 21.31%.

UPLC-MS-Based Non-targeted Analysis of Endogenous Metabolite Changes in the Leaves of Scabiosa tschiliensis Grüning Induced by 6-Benzylaminopurine and Kinetin

In vitro propagation technology with plant growth regulators (PGRs) is generally applied in the cultivation of Scabiosa tschiliensis, which can solve collection difficulties and limited resources of S. tschiliensis. Nevertheless, comprehensive metabolomic evaluation on S. tschiliensis with PGR effects is still lacking. In this work, a non-targeted metabolomics approach, coupled with statistical and pathway enrichment analysis, was used to assess the regulatory influences of 6-benzylaminopurine (6-BA) and kinetin (KT) applied in S. tschiliensis. The results showed that the PGRs affect metabolism differentially, and the addition of 6-BA and KT can increase different secondary metabolites. In the two PGR groups, some primary metabolites such as L-phenylalanine, L-tyrosine, L-arginine, L-asparagine, and D-proline were significantly reduced. We suspect that under the action of PGRs, these decreased amino acids are derived into secondary metabolites such as umbelliferone, chlorogenic acid, and glutathione. Additionally, some of those secondary metabolites have a biological activity and can also promote the plant growth. Our results provide a basis for the targeted cultivation and utilization of S. tschiliensis, especially the expression of metabolites related to PGR application.

Systematic profiling of the effective ingredients and mechanism of Scabiosa comosa and S. tschilliensis against hepatic fibrosis combined with network pharmacology

Scabiosa comosa and S. tschilliensis (SCST) are traditionally used for liver diseases in Mongolian medicine. However, their active ingredients and molecular mechanisms are unknown. The present study employed network pharmacology and experimental verification approaches to decipher the common pharmacological mechanisms of SCST on liver fibrosis, which is the key step in liver diseases. We predicted the targets of all available SCST ingredients with the SWISS and SuperPred servers and clustered the targets related to liver fibrosis from DrugBank, the OMIM database and the literature. We further evaluated the links between the herbal ingredients and pharmacological actions to explore the potential mechanism of action of SCST. We found that the PPARG signalling pathway could be regulated by SCST for liver fibrosis through enrichment analysis. The key targets included 8 co-targets, including HSP90AA1, PPARG, HSP90AB1, STAT1, etc., which play pivotal roles in the pathogenesis of liver fibrosis. Additionally, the top 15 key compounds included flavonoids and phenylpropanoids. Central to the pathogenesis of liver fibrosis is trans-differentiation or activation of hepatic stellate cells (HSCs). Therefore, LX2 cells, an immortalized human HSC line, were studied. Here, a total 37 components were isolated and identified from the inflorescences of SCST, including the new compound tschilliensisin, and the first separated components, β-sitosterol and luteolin, and these compounds were assessed against anti-hepatic fibrosis. An MTT assay and quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analyses demonstrated that the flavonoids of SCST revealed anti-hepatic fibrosis effects via anti-proliferation and increases in the Stat1, Pparg, Hsp90aa1 genes and STAT1 and PPARG proteins in LX-2 cells. In conclusion, these results indicate that SCST has multi-targeted and multi-component synergistic anti-hepatic fibrosis effects.

Antiviral Role of Phenolic Compounds against Dengue Virus: A Review

Phenolic compounds have been related to multiple biological activities, and the antiviral effect of these compounds has been demonstrated in several viral models of public health concern. In this review, we show the antiviral role of phenolic compounds against dengue virus (DENV), the most widespread arbovirus globally that, after its re-emergence, has caused multiple epidemic outbreaks, especially in the last two years. Twenty phenolic compounds with anti-DENV activity are discussed, including the multiple mechanisms of action, such as those directed against viral particles or viral proteins, host proteins or pathways related to the productive replication viral cycle and the spread of the infection.

Rapid and comprehensive profiling of α-glucosidase inhibitors in Buddleja Flos by ultrafiltration HPLC-QTOF-MS/MS with diagnostic ions filtering strategy

Buddleja Flos is used as yellow rice colorant and a well-known traditional Chinese medicine. But its biochemical profiling is still lack due to complex matrix. Here, ultrafiltration high-performance liquid chromatograph-quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS/MS) with diagnostic ions filtering strategy was proposed for rapid and comprehensive investigation of its α-glucosidase inhibitors. As a result, 33 bioactive compounds (13 phenylethanoid glycosides and 20 flavonoids) were successfully screened and identified. In addition, α-glucosidase inhibitory activities of twenty-two references were verified. Six flavonoid aglycones (4, 28, and 30-33) showed excellent α-glucosidase inhibitory activities (IC₅₀, from 5.11 ± 0.85 to 32.49 ± 9.76 μg/mL), much higher than that of acarbose (IC₅₀, 195.49 ± 10.05 μg/mL). Five flavonoid-monoglycosides (7, 12, 13, 20, and 22) presented moderate inhibitory activities with IC₅₀ from 160.98 ± 23.19 to 249.37 ± 35.83 μg/mL. Results showcased the high efficiency of proposed strategy in profiling of bioactive compounds from natural products.

Phytochemical investigation of Scabiosa sicula guided by a preliminary HPLC-ESIMSn profiling

The genus Scabiosa (Caprifoliaceae) is represented by 80 species, widely used as medicinal plants for their positive effects on human diseases. On the basis of the interesting biological activity shown by Scabiosa spp., the phytochemical investigation of Scabiosa sicula L., never investigated before, was carried out. An initial LC-MS profile of the MeOH extract of S. sicula whole plant guided the isolation of 34 compounds, of which the structures were unambiguously elucidated by NMR analysis as phenolic compounds and triterpene saponins, among which eight undescribed compounds. Moreover, the total phenolic content of S. sicula methanol extract has been evaluated. On the basis of the pharmacological activities reported for Scabiosa species the antioxidant activity of the methanol extract was tested by TEAC and DPPH assays. Finally, the α-glucosidase inhibitory activity of the methanol extract was assayed, showing an IC₅₀ value (49 μg/mL) comparable to that exerted by acarbose (90 μg/mL), used as positive control.

Pharmacological action and potential targets of chlorogenic acid

Chlorogenic acid is a widely distributed natural compound with many important pharmacological effects, which are found in a variety of plants. It is also an important secondary metabolite in plants. As a natural plant extract from a wide range of sources, in vitro and in vivo studies have found that the main pharmacological effects of chlorogenic acid are antioxidant, antiinflammatory, antibacterial, antiviral, hypoglycemic, lipid lowering, anticardiovascular, antimutagenic, anticancer, immunomodulatory, etc. Therefore it may play an important role in promoting human health. For example, it can provide new ideas and new ways for the prevention and treatment of cardiovascular disease, cancer, diabetes, and other chronic diseases, but the specific mechanism of action is unclear. Due to the difficulty of extraction and purification, poor stability, poor solubility, low absolute bioavailability of oral administration, the possibility of allergies caused by injection, and so on, there are difficulties in its medicinal research and development. The further study of chlorogenic acid will provide an important theoretical basis for its rational use.

Scabiosa Genus: A Rich Source of Bioactive Metabolites

The genus Scabiosa (family Caprifoliaceae) is considered large (618 scientific plant names of species) although only 62 have accepted Latin binominal names. The majority of the Scabiosa species are widely distributed in the Mediterranean region and some Scabiosa species are used in traditional medicine systems. For instance, Scabiosa columbaria L. is used traditionally against diphtheria while S. comosa Fisch. Ex Roem. and Schult. is used in Mongolian and Tibetan traditional medical settings to treat liver diseases. The richness of Scabiosa species in secondary metabolites such as iridoids, flavonoids and pentacyclic triterpenoids may contribute to its use in folk medicine. Details on the most recent and relevant pharmacological in vivo studies on the bioactive secondary metabolites isolated from Scabiosa species will be summarized and thoroughly discussed.

Variation of active constituents and antioxidant activity in Scabiosa tschiliensis Grunning from different stages

It has been claimed that inflorescences of Scabiosa tschiliensis Grunning (ST) may prevent liver diseases because of its higher chlorogenic acid. There was scant information on the phytochemical profiles and antioxidant activities of the whole plant from different growing stages. The changes of active-compounds and antioxidant activities of ST from three growing stages were studied. Total phenolic and flavonoid contents were analyzed and ranged from 0.00 to 140.03 mg GAE/g and 9.10 to 460.01 mg RE/g, respectively. The pre-flowering stage ethyl acetate (PFSEA) fraction of ST appeared to contain the highest content of chlorogenic acid, and demonstrated the highest DPPH radical-scavenging activity with the IC₅₀ value of 8.47 ± 0.23 µg/mL which was nearly equal to the IC₅₀ value of vitamin C (7.60 ± 0.61 µg/mL). Principal component analysis suggested that the PFSEA fraction of ST might be a desirable antioxidant natural resource due to the highest potential antioxidant properties.

A New Secoiridoid Glucoside, and a Metabolite Profile of Scabiosa lucida

Fourteen secondary metabolites, including a new secoiridoid glucoside (1), were isolated from the aerial parts of Scabiosa lucida by a combination of column chromatography, preparative and semi-preparative HPLC. They were identified by extensive NMR, and ESI-MS experiments, and by comparison with literature data.

Hepato-protective effects and chemical constituents of a bioactive fraction of the traditional compound medicine-Gurigumu-7

BACKGROUND

Gurigumu-7 is an important traditional Mongolian medicine frequently used for liver diseases. However, the pharmacological effects and the bioactive constituents are not well understood.

METHOD

This research was to use CCl4-induced liver damage in mice to investigate the hepatoprotective effects of Gurigumu-7 and the methanol eluted fraction from a DIAION column of an extract of Gurigumu-7 (MF). The chemical constituents of MF were analyzed by UPLC-MS.

RESULTS

Pretreated orally with MF (66, 132 and 264 mg/kg) once a day for 4 days dose-dependently suppressed CCl4-induced mice liver histopathological changes and serum aminotransferase activities (alanine transaminase: 1144.0 ± 787.2 v.s. 2461.8 ± 1072.7 U/L, p < 0.05; aspartate transaminase: 1173 ± 785.3 v.s. 2506.6 ± 1140.7 U/L, p < 0.01). MF treated group demonstrated increased levels of SOD (108.19 ± 30.32 v.s. 75.75 ± 5.37 U/mg protein, p < 0.01) but decreased levels of malonyldialdehyde (7.68 ± 1.95 v.s. 44.32 ± 16.68 nmol/mg protein, p < 0.01) compared to the CCl4 control group. More than 30 chemical constituents were quantified, and MF was found to be rich in ellagic acid (297.97 mg/g), luteolin and its glucosides (35.10 mg/g), apigenin and its glucosides (>30 mg/g), ursolic acid (14.91 mg/g), bidenoside C (8.75 mg/g), and proanthocyanidins (15.64 mg/g in proanthocyanidin A2 equivalent).

CONCLUSION

The methanol eluted fraction (MF) from a DIAION column of an extract of the Mongolian medicine-Gurigumu-7 was found to be more hepatoprotective than Gurigumu-7. The results suggested that MF is a promising bioactive fraction for the development of new hepatoprotective medicine with better formulation and quality control properties.

Characterisation of phenolic antioxidants in Scabiosa arenaria flowers by LC-ESI-MS/MS and NMR

OBJECTIVES

This work describes the bioguided fractionation of the flower's ethyl acetate fraction of Scabiosa arenaria Forssk. (Dipsacaceae).

METHODS

The identification of the pure compound isolated has been studied by mono-dimensional NMR experiments. The mixture of phenolic compounds was analysed by LC-ESI-MS/MS. The antioxidant activity has been evaluated by the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.

KEY FINDINGS

The bioguided fractionation of the flower's ethyl acetate fraction of Scabiosa arenaria led to the isolation of a pure compound: luteolin. The mixture of three phenolic compounds was identified as: 1, 4-O-dicaffeoylquinic acid, apigenin 7-O-glucoside and luteolin-7-O-glucoside. Two of which are reported here for the first time in Scabiosa genus. Luteolin had the highest antioxidant activity with an IC50 value of 0.02 ± 0.007 mg/ml, followed by the three phenolic compounds with an IC50 value of 0.025 ± 0.008 mg/ml.

CONCLUSIONS

The results of the present work indicate that S. arenaria flower's ethyl acetate extract could be used as natural antioxidant agents in food preservation and human health.