Spectrum-effect relationship between ultra-performance liquid chromatography fingerprints and melanogenic effect of Vernonia anthelmintica effective part.

The fingerprint of Vernonia anthelmintica effective part (VAEP) from 15 different producing areas was established, followed by cluster analysis and principal component analysis. The relationship between the fingerprint and the melanogenesis-promoting activity of VAEP was then analyzed using the grey correlation degree and the orthogonal partial least square method. The characteristic peaks reflecting the pharmacodynamic effect of VAEP were identified as vernodalin, 3,5-O-dicaffeoyl quinic acid (3,5-diCQA), and butin. Based on the distribution characteristics of these components in plants from different habitats and the verification of results from the spectrum-effect relationship, vernodalin and 3,5-diCQA can be used as characteristic components for quality control and pharmacodynamic assessment of V. anthelmintica products. This research establishes a theoretical foundation for planting areas and provides a scientific evaluation of the melanogenesis-promoting effect of V. anthelmintica.

Identification of promising multi-targeting inhibitors of obesity from Vernonia amygdalina through computational analysis.

Vernonia amygdalina, a widely consumed West African food herb, can be a boon in the discovery of safe anti-obesity agents given the extensive reports on its anti-obesity and antidiabetic potentials. The main aim of this study was to screen 78 Vernonia-Derived Phytocompounds (VDPs) against the active site regions of Human Pancreatic Lipase (HPL), Human Pancreatic Amylase and Human Glucosidase (HG) as drug targets associated with obesity in silico. Structure-based virtual screening helped to identify Luteolin 7-O-glucuronoside and Andrographidoid D2 as hit compounds with dual targeting tendency towards the HPL and HG. Analysis of the molecular dynamic simulation trajectory files of the ligand-receptor complexes as computed from the thermodynamic parameters plots showed not only increased flexibility and greater interaction potential of the active site residues of the receptor towards the VDPs as indicated by the root mean square fluctuation but also higher stability as indicated by the root mean square deviation, radius of gyration and number of hydrogen bonds. The cluster analysis further showed that the interactions with important residues were preserved in the dynamic environment. These observations were further verified from Molecular Mechanics Generalized Born Surface Area Analysis, which also showed that residual contributions to the binding free energies were mainly from catalytic residues at the active sites of the enzymes. The hit compounds also feature desirable physicochemical properties and drug-likeness. This study provides in silico evidence for the inhibitory potential of phytochemicals from Vernonia amygdalina against two target enzymes in obesity.

Evaluation of the Antibacterial and Antibiofilm Effects of Ethyl Acetate Root Extracts from Vernonia adoensis (Asteraceae) against Pseudomonas aeruginosa.

There is an increase in mortality and morbidity in the health facilities due to nosocomial infections caused by multidrug-resistant nosocomial bacteria; hence, there is a need for new antibacterial agents. Vernonia adoensis has been found to possess medicinal value. Plant phytochemicals may have antimicrobial activity against some resistant pathogens. The antibacterial efficacy of root extracts against Staphylococcus aureus and Pseudomonas aeruginosa was investigated using the microbroth dilution method. All extracts from the roots had an inhibitory effect on the growth of both bacteria, with the most susceptible being P. aeruginosa. The most potent extract was the ethyl acetate extract which caused a percentage inhibition of 86% against P. aeruginosa. The toxicity of the extract was determined on sheep erythrocytes, and its effect on membrane integrity was determined by quantifying the amount of protein and nucleic acid leakage from the bacteria. The lowest concentration of extract used, which was 100 µg/ml, did not cause haemolysis of the erythrocytes, while at 1 mg/ml of the extract, 21% haemolysis was observed. The ethyl acetate extract caused membrane impairment of P. aeruginosa, leading to protein leakage. The effect of the extract on the biofilms of P. aeruginosa was determined in 96-microwell plates using crystal violet. In the concentration range of 0-100 µg/ml, the extract inhibited the formation of biofilms and decreased the attachment efficiency. The phytochemical constituents of the extract were determined using gas chromatography-mass spectrometry. Results of analysis showed the presence of 3-methylene-15-methoxy pentadecanol, 2-acetyl-6-(t-butyl)-4-methylphenol, 2-(2,2,3,3-tetrafluoropropanoyl) cyclohexane-1,4-dione, E,E,Z-1,3,12-nonadecatriene-5,14-diol, and stigmasta-5,22-dien-3-ol. Fractionation and purification will elucidate the potential antimicrobial compounds which are present in the roots of V. adoensis.

Polyoxygenated Stigmastane-Type Steroids from Vernonia kotschyana Sch. Bip. ex Walp. and Their Chemophenetic Significance.

Four polyoxygenated stigmastanes (1-4) alongside known analogues (7-8) and flavonoids (5-6) were isolated from a dichloromethane/methanol (1:1, v/v) extract of the whole plant of Vernonia kotschyana Sch. Bip. ex Walp. (Asteraceae). Their structures were determined by means of spectroscopic and spectrometric analysis. The relative stereochemistry of the new compounds was established and confirmed via biosynthesis evidence and cyclization of 1 under acidic conditions. A plausible biosynthetic pathway to the new compounds and the chemophenetic significance of the isolated constituents were also discussed. The crude extract, fractions, and compounds (1-3) were assessed for their antibacterial activity against five highly prevalent bacterial strains. The fractions and compounds showed low to moderate activity with minimal inhibitory concentrations (MICs) > 125 µg/mL.

[Melanogenesis of quality markers in Vernonia anthelmintica Injection based on UPLC-Q-TOF-MS combined network pharmacology].

This study aimed to evaluate the biological effect and mechanism of Vernonia anthelmintica Injection(VAI) on melanin accumulation. The in vivo depigmentation model was induced by propylthiouracil(PTU) in zebrafish, and the effect of VAI on melanin accumulation was evaluated based on the in vitro B16F10 cell model. The chemical composition of VAI was identified according to the high-performance liquid chromatography quadrupole-time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS). Network pharmaco-logy was applied to predict potential targets and pathways of VAI. A "VAI component-target-pathway" network was established, and the pharmacodynamic molecules were screened out based on the topological characteristics of the network. The binding of active molecules to key targets was verified by molecular docking. The results showed that VAI promoted tyrosinase activity and melanin production in B16F10 cells in a dose-and time-dependent manner and could restore the melanin in the body of the zebrafish model. Fifty-six compounds were identified from VAI, including flavonoids(15/56), terpenoids(10/56), phenolic acids(9/56), fatty acids(9/56), steroids(6/56), and others(7/56). Network pharmacological analysis screened four potential quality markers, including apigenin, chrysoeriol, syringaresinol, and butein, involving 61 targets and 65 pathways, and molecular docking verified their binding to TYR, NFE2L2, CASP3, MAPK1, MAPK8, and MAPK14. It was found that the mRNA expression of MITF, TYR, TYRP1, and DCT in B16F10 cells was promoted. By UPLC-Q-TOF-MS and network pharmacology, this study determined the material basis of VAI against vitiligo, screened apigenin, chrysoeriol, syringaresinol, and butein as the quality markers of VAI, and verified the efficacy and internal mechanism of melanogenesis, providing a basis for quality control and further clinical research.

Sesquiterpene Lactones from Vernonia tufnelliae: Structural Characterization and Biological Evaluation.

The genus Vernonia is an extremely rich source of biologically active sesquiterpene lactones. The present report describes the spectroscopic structure elucidation and the cytotoxic and antimicrobial properties of five hitherto unknown germacranolide-like sesquiterpenoids and several known compounds. These new derivatives include a compound (1) with an unprecedented 10/5/5/6 tetracyclic framework featuring a hexahydro-1H,3H,7H-furo[3',4':3,4]furo[3,2-c]pyridin-1-one core resulting from an intramolecular cyclization cascade involving a methacrylate substituent and a low molecular weight amine. Furthermore, an elemane-germacranolide hybrid (2) and three amino acid-derived lactones (3-5) were characterized. A plausible biosynthetic pathway to the key alkaloid is presented, while shielding tensor calculations using DFT in combination with the DP4+ method were applied to elucidate its stereostructure. The newly characterized compounds along with ten known sesquiterpene lactones and phenolic compounds have been isolated from Vernonia tufnelliae, a medicinal plant from the western region of Cameroon. Their structures were consistent with spectroscopic and spectrometric data recorded. The present report is the first investigation of the chemistry and biology of V. tufnelliae.

Tautomeric phytosterols from Vernonia amygdalina Delile and their anti-cervical cancer activity.

Vernonia amygdalina Delile is generally used as green vegetables for cuisine in Nigeria and health tea or products in southeast of china. It was also used as folk medicine for the treatment of anti-helminth, febrifuge, digestive tonic and wounds. In this study, eleven undescribed phytosterols (1-2, 4-12) and six known analogues (3, 13-17) were isolated from the stems of V. amygdalina. Their structures including absolute configurations were elucidated by comprehensive spectroscopic methods (1D and 2D NMR, HRESIMS), X-ray diffraction and comparison of their ECD spectra. Besides, the tautomerism of phytosterols (1, 3-6, 12-17) with hemiacetal moiety were analyzed by solution NMR with different deuterated solvent and variable-temperature experiments. In addition, the cytotoxic activities of isolates against HeLa cells were evaluated. As a result, compound 10 exhibited the most potent anti-cervical cancer activity with the IC50 of 22.44 µM. Mechanism studies indicated that 10 triggered HeLa cells apoptosis through activating caspase signaling pathway. Furthermore, 10 could arrest the cell cycle in S phase and suppress the activation of the PI3K/AKT/mTOR pathway, leading to the inhibition of HeLa cells proliferation.

Can Crude Oil Exploration Influence the Phytochemicals and Bioactivity of Medicinal Plants? A Case of Nigerian Vernonia amygdalina and Ocimum gratissimum.

The Nigerian Niger-Delta crude oil exploration often results in spills that affect indigenous medicinal plant biodiversity, likely changing the phytochemical profile of surviving species, their bioactivity or toxicity. In crude oil-rich Kokori and crude oil-free Abraka, classic examples of indigenous plants occupying the medicine-food interface include Vernonia amygdalina (VAL) and Ocimum gratissimum leaves (OGL). These plants are frequently utilised during pregnancy and in anaemia. To date, no scientific investigation has been reported on the potential changes to the phytochemical or bioactivity of the study plants. To discuss the similarities and dissimilarities in antisickling bioactivity and phytochemicals in VAL and OGL collected from Kokori (VAL-KK and OGL-KK) and Abraka (VAL-AB and OGL-AB), in silico, in vitro and comparative UPLC-QTOF-MS analysis was performed. Nine unique compounds were identified in OGL-KK, which have never been reported in the literature, while differences in antisickling potentials were observed in VAL-KK, OGL-KK and, VAL-AB, OGL-AB. Our findings show that VAL-AB and OGL-AB are richer and more diverse in phytochemicals and displayed a slightly higher antisickling activity than VAL-KK and OGL-KK. Ligand-based pharmacophore modelling was performed to understand the potential compounds better; this study may provide a basis for explaining the effect of crude oil spills on secondary metabolites and a reference for further research.

Secondary metabolite contents and antimicrobial activity of leaf extracts reveal genetic variability of Vernonia amygdalina and Vernonia calvoana morphotypes.

Vernonia species (Asteraceae) are indigenous medicinal and food leaf vegetables commonly consumed in some African countries like Cameroon where they constitute a staple dish called "ndolé." Previous studies have demonstrated the nutritional importance of Vernonia, but there is little knowledge of their agronomic value and genetic potentials. Wide genetic variability in the genus has been established earlier through the study of its pollen. However, to the best of our understanding, no such study has been undertaken on the genetic variability of Vernonia with respect to its secondary metabolites. This study was therefore aimed at evaluating the genetic variability of Vernonia amygdalina (VAA and VALF) and V. calvoana (VCAB, VCAV, VCSB, and VCSV) morphotypes in 2016 based on secondary metabolite content and antimicrobial properties. This involved phytochemical analysis by HPLC/MS for the detection of alkaloids, flavonoids, phenols, and tannins in leaves from each of the six genotypes. Results showed that all tested genotypes are rich in phenols (18 analyzed), flavonoids, and tannins with, VAA richer in phenols (206.1 ± 3.12 µg/g of dry extract), followed by VCAV (197.9 ± 18.03 µg/g). The lowest level of flavonoid was found in VCSV (81.6 ± 7.21 µg/g), while the highest was from VCAB (132.8 ± 31.5 µg/g). VCSV (56.3 ± 4.08 µg/g) had the lowest level of tannins, while VCAB (97.8 ± 23.8 µg/g) had the highest levels. Assessment of antimicrobial activity of leaf extracts from the six genotypes was done by culture on Mueller Hinton (MH) agar and MH broth agar for bacteria and in Sabouraud dextrose agar and Sabouraud dextrose broth media for fungi, respectively. All morphotypes exhibited inhibitory activity on bacteria except VAA, with isoquercetin characteristic of VCSV. Chemotaxonomic analyses of Vernonia morphotypes highlighted the genetic diversity within species and variability of antimicrobial properties of ethanolic leaf extracts among morphotypes. These results provide baseline data in the valuation of genetic resources and the establishment of improvement programs.

Antinociceptive and sedative activity of Vernonia patula and predictive interactions of its phenolic compounds with the cannabinoid type 1 receptor.

When tested in the acetic acid-induced writhing and formalin-induced paw-licking tests, the ethanol extract of Vernonia patula (VP) aerial parts showed significant antinociceptive activity. In neuropharmacological tests, it also significantly delayed the onset of sleep, increased the duration of sleeping time, and significantly reduced the locomotor activity and exploratory behaviour of mice. Five phenolic compounds, namely gallic acid, vanillic acid, caffeic acid, quercetin and kaempferol, were detected in VP following HPLC-DAD analysis. The presence of these phenolic compounds in VP provides some support for the observed antinociceptive and sedative effects. A computational study was performed to predict the binding affinity of gallic acid, vanillic acid, caffeic acid, quercetin and kaempferol towards the cannabinoid type 1 (CB1) receptor. Caffeic and vanillic acid showed the highest probable ligand efficiency indices towards the CB1 target. Vanillic acid displayed the best blood-brain barrier penetration prediction score. These findings provide some evidence for the traditional use of VP to treat pain.

Repellent Effects of Selected Organic Leaf Extracts of Tithonia diversifolia (Hemsl.) A. Gray and Vernonia lasiopus (O. Hoffman) against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae).

INTRODUCTION: Sitophilus zeamais infestation is among the major setbacks to sustainable maize farming and availability. It causes an estimated annual loss of 5-10% and 20-30% of the total maize grains loss in the temperate and tropical zones, respectively. Although synthetic pesticides are quick and effective in managing crop pests, their overuse and misuse is discouraged due to their detrimental effects on human and environment. Natural pesticidal products that are extracted from plants are particularly gaining importance as an alternative to synthetic pesticides. They are available, easily biodegraded and have low toxicity to nontarget organisms. Most botanical pesticides act on insects by repelling them away from the crops in the field or in the stores. Therefore, this study aimed to determine repellency potential of organic leaf extracts of Tithonia diversifolia and Vernonia lasiopus on S. zeamais. Materials and methods. The phytochemical profile of T. diversifolia and V. lasiopus was determined using GC-MS. Laboratory-based experiments were carried out using area preference method to assess the efficacy of the extracts against weevils for a test period of 5 h. Six groups of experiments were set up with ten S. zeamais in each test: positive control (Actellic), negative control (solvent only), and four different experimental extract concentrations (25, 50, 75, and 100%). RESULTS: The results indicated that T. diversifolia and V. lasiopus leaf extracts possess potent repellency effect on weevils. All the extracts simply discouraged S. zeamais from the treated areas recording significantly good levels of repellent activities between 26 and 96%. Furthermore, the GC-MS analysis manifested the presence of bioactive compound in the extracts which are associated with the repellency effects. CONCLUSION: The study scientifically confirms the traditional use of the T. diversifolia and V. lasiopus and provides important platform for further study on the extracts as bioresource of botanical repellent.

Molecular Docking and Molecular Dynamics Simulation Studies of Triterpenes from Vernonia patula with the Cannabinoid Type 1 Receptor.

A molecular docking approach was employed to evaluate the binding affinity of six triterpenes, namely epifriedelanol, friedelin, α-amyrin, α-amyrin acetate, ß-amyrin acetate, and bauerenyl acetate, towards the cannabinoid type 1 receptor (CB1). Molecular docking studies showed that friedelin, α-amyrin, and epifriedelanol had the strongest binding affinity towards CB1. Molecular dynamics simulation studies revealed that friedelin and α-amyrin engaged in stable non-bonding interactions by binding to a pocket close to the active site on the surface of the CB1 target protein. The studied triterpenes showed a good capacity to penetrate the blood-brain barrier. These results help to provide some evidence to justify, at least in part, the previously reported antinociceptive and sedative properties of Vernonia patula.

The Great Capacity on Promoting Melanogenesis of Three Compatible Components in Vernonia anthelmintica (L.) Willd.

To investigate a possible methodology of exploiting herbal medicine and design polytherapy for the treatment of skin depigmentation disorder, we have made use of Vernonia anthelmintica (L.) Willd., a traditional Chinese herbal medicine that has been proven to be effective in treating vitiligo. Here, we report that the extract of Vernonia anthelmintica (L.) Willd. effectively enhances melanogenesis responses in B16F10. In its compound library, we found three ingredients (butin, caffeic acid and luteolin) also have the activity of promoting melanogenesis in vivo and in vitro. They can reduce the accumulation of ROS induced by hydrogen peroxide and inflammatory response induced by sublethal concentrations of copper sulfate in wild type and green fluorescent protein (GFP)-labeled leukocytes zebrafish larvae. The overall objective of the present study aims to identify which compatibility proportions of the medicines may be more effective in promoting pigmentation. We utilized the D-optimal response surface methodology to optimize the ratio among three molecules. Combining three indicators of promoting melanogenesis, anti-inflammatory and antioxidant capacities, we get the best effect of butin, caffeic acid and luteolin at the ratio (butin:caffeic acid:luteolin = 7.38:28.30:64.32) on zebrafish. Moreover, the effect of melanin content recovery in the best combination is stronger than that of the monomer, which suggests that the three compounds have a synergistic effect on inducing melanogenesis. After simply verifying the result, we performed in situ hybridization on whole-mount zebrafish embryos to further explore the effects of multi-drugs combination on the proliferation and differentiation of melanocytes and the expression of genes (tyr, mitfa, dct, kit) related to melanin synthesis. In conclusion, the above three compatible compounds can significantly enhance melanogenesis and improve depigmentation in vivo.

Structure-activity relationship and in vitro inhibition of human cytochrome CYP2A6 and CYP2A13 by flavonoids.

Cigarette smoking is one of the major risk factors of various diseases including respiratory diseases and lung cancer. While the liver-specific CYP2A6 is associated with the nicotine clearance and smoking addiction, the metabolic activation of the tobacco-specific nitrosamine by lung-specific CYP2A13 can lead to lung tumorigenesis.It has been reported that inhibition of CYP2A6 and CYP2A13 enzymes by flavonoids constituents could be an aids in smoking cessation. This study demonstrates the inhibition activity of kaempferol and myricetin and the structure-function relationship of these two flavonoids and previously isolated flavonoids from Vernonia cinerea and Pluchea indica against both enzymes.Kaempferol could inhibit CYP2A6 with Kic value of 1.77 ± 0.47 µM while inhibit CYP2A13 with Kic value of 0.12 ± 0.01 µM. Myricetin could inhibit CYP2A6 with Kic value of 4.06 ± 0.52 µM while inhibit CYP2A13 with Kic value of 1.88 ± 0.03 µM.Molecular docking indicated that CYP2A13 enzyme has strong hydrophobic interaction with ring B of flavonoids compared to CYP2A6 enzyme. The presence of the hydroxyl group at C3 position of ring C and the hydroxyl group at C5' of ring B affected inhibitory activity on both enzymes.

Antibacterial Flavonoids and Other Compounds from the Aerial Parts of Vernonia guineensis Benth. (Asteraceae).

An extensive phytochemical study of the aerial parts of Vernonia guineensis Benth. (Asteraceae) led to the isolation of a new flavone, vernoguinoflavone and a naturally isolated glycerol ester, eicosanoic acid 2-hydroxy-1,3-propanediyl ester, together with eighteen known secondary metabolites including quercetin, luteolin, vernopicrin, vernomelitensin, ß-amyrin, oleanolic acid, ursolic acid, lupeol, betulinic acid, ß-carotene, a mixture of stigmasterol and ß-sitosterol, ß-sitosterol-3-O-ß-D-glucoside, 2,3-dihydroxypropyl heptacosanoate, pentacosanoic acid, docosan-1-ol, tritriacontan-1-ol, and heptatriacontan-1-ol. Eleven compounds are reported herein for the first time from this species. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses, particularly 1D and 2D NMR, and HR-ESI-MS and by comparison of their data with those reported in the literature. The crude extract, fractions and some isolated compounds were evaluated for their antibacterial activity against Gram-negative bacteria: Escherichia coli (ATCC 25922), Shigella flexineri (NR 518), Salmonella muenchen, Salmonella typhimurium and Salmonella typhi (ATCC 19430). All the tested compounds demonstrated inhibitory activities against the tested enteric bacteria with MIC values ranging from 3.12 to 100 µg/ml. Three flavonoids isolated from the most active fraction demonstrated the best bioactivities against Escherichia coli, Salmonella muenchen and Salmonella typhimurium with MIC values ranging from 3.12 to 25 µg/mL.

Vernonia calvoana Shows Promise towards the Treatment of Ovarian Cancer.

The treatment for ovarian cancers includes chemotherapies which use drugs such as cisplatin, paclitaxel, carboplatin, platinum, taxanes, or their combination, and other molecular target therapies. However, these current therapies are often accompanied with side effects. Vernonia calvoana (VC) is a valuable edible medicinal plant that is widespread in West Africa. In vitro data in our lab demonstrated that VC crude extract inhibits human ovarian cancer cells in a dose-dependent manner, suggesting its antitumor activity. From the VC crude extract, we have generated 10 fractions and VC fraction 7 (F7) appears to show the highest antitumor activity towards ovarian cancer cells. However, the mechanisms by which VC F7 exerts its antitumor activity in cancer cells remain largely unknown. We hypothesized that VC F7 inhibits cell proliferation and induces DNA damage and cell cycle arrest in ovarian cells through oxidative stress. To test our hypothesis, we extracted and fractionated VC leaves. The effects of VC F7 were tested in OVCAR-3 cells. Viability was assessed by the means of MTS assay. Cell morphology was analyzed by acridine orange and propidium iodide (AO/PI) dye using a fluorescent microscope. Oxidative stress biomarkers were evaluated by the means of lipid peroxidation, catalase, and glutathione peroxidase assays, respectively. The degree of DNA damage was assessed by comet assay. Cell cycle distribution was assessed by flow cytometry. Data generated from the MTS assay demonstrated that VC F7 inhibits the growth of OVCAR-3 cells in a dose-dependent manner, showing a gradual increase in the loss of viability in VC F7-treated cells. Data obtained from the AO/PI dye assessment revealed morphological alterations and exhibited characteristics such as loss of cellular membrane integrity, cell shrinkage, cell membrane damage, organelle breakdown, and detachment from the culture plate. We observed a significant increase (p < 0.05) in the levels of malondialdhyde (MDA) production in treated cells compared to the control. A gradual decrease in both catalase and glutathione peroxidase activities were observed in the treated cells compared to the control. Data obtained from the comet assay showed a significant increase (p < 0.05) in the percentages of DNA cleavage and comet tail length. The results of the flow cytometry analysis indicated VC F7 treatment caused cell cycle arrest at the S-phase checkpoint. Taken together, our results demonstrate that VC F7 exerts its anticancer activity by inhibiting cell proliferation, inducing DNA damage, and causing cell cycle arrest through oxidative stress in OVAR-3 cells. This finding suggests that VC F7 may be a potential alternative dietary agent for the prevention and/or treatment of ovarian cancer.

[HPLC specific chromatogram of Vernonia anthelmintica and determination of six components].

This work aims to establish an HPLC specific chromatogram and determine six components of Vernonia anthelmintica with chlorogenic acid, isochlorogenic acid B, isochlorogenic acid A, isochlorogenic acid C, scutellarein and luteolin as index components. HPLC analysis was performed on a Waters Xbridge C_(18) column(4.6 mm×250 mm, 5 µm) with gradient elution of acetonitrile-0.05% trifluoroacetic acid solution at a flow rate of 1.0 mL·min~(-1). The detection wave length was 360 nm and the column temperature was 30 ℃. Chemometrics software Chempattern was employed to analyze the data. HPLC specific chromatogram of V. anthelmintica was established and six characteristic peaks were marked. Six characteristic peaks were simultaneously determined by HPLC within 50 min. The contents of the six components in 13 batch samples of V. anthelmintica were 0.14%-0.68%, 0.44%-0.74%, 0.63%-1.01%, 0.14%-0.71%, 0.15%-0.26% and 0.010%-0.030%, respectively. The HPLC specific chromatogram of V. anthelmintica, together with determination of six components showed strong specificity, and it can be used for the quality control of the crude drug.

Bioactive Sesquiterpene Lactones Isolated from the Whole Plants of Vernonia cinerea.

Twelve sesquiterpene lactones were isolated from the whole plants of Vernonia cinerea. These included eight new compounds, vercinolides A-H (1-8), along with four known substances (9-12). The structures of the new compounds were determined by 1D and 2D NMR experiments and mass spectrometric methods. The absolute configurations of compounds 1-8 were determined by Mosher experiments and ECD data. Compounds 1-8 are the first examples of a new class of sesquiterpene lactones possessing a rare 4α,10α-ether ring and a 2,14-ether ring. Compounds 1-4, 6, 8, 10, and 12 were evaluated for their cytotoxic and anti-inflammatory activities. Compounds 10 and 12 exhibited inhibitory effects against nitric oxide production in lipopolysaccharide-activated RAW 264.7 mouse macrophage cells with IC50 values of 21 and 23 µM, respectively. Both compounds were inactive for HeLa cells (IC50 > 10 µM).

Vernodalidimer L, a sesquiterpene lactone dimer from Vernonia extensa and anti-tumor effects of vernodalin, vernolepin, and vernolide on HepG2 liver cancer cells.

Vernonia extensa, known as "Phim Phai Lin" in Thai, is distributed in most regions of Thailand. The plant has been used in Ayurveda and traditionally used to treat malaria and cancer, and possesses several sesquiterpene lactones. This study aimed to investigate and identify the active constituents by bioactivity-based analysis, as well as to evaluate the cytotoxic activity of V. extensa by MTT or XTT assays in ten cancer cell lines (Liver HepG2 and S102; Bile duct HuCCA-1; Leukemia HL-60 and MOLT-3; Lung A549 and H69AR; Breast MDA-MB-231 and T47D; Cervical HeLa). Bioactivity-guided fractionation and semi-preparative HPLC purification were used to separate the bioactive constituents. Apoptosis-inducing activity and cell cycle inhibitory effect of selected active compounds were determined on HepG2 cells by flow cytometric analysis. Bioactivity-guided fractionation of the CH2Cl2 extract and chemical investigation of the cytotoxic fractions led to the isolation of a new sesquiterpenoid pseudo-dimer named vernodalidimer L, together with eight known sesquiterpenoids from the aerial part of V. extensa. The structures of the isolates were elucidated based on spectroscopic analysis, including 1D and 2D NMR and HRMS. Vernolide has potent broad-spectrum cytotoxicity with IC50 values in the range of 0.91-13.84 µM, against all ten cancer cell lines. The annexin-V flow cytometric analysis showed that vernodalin, vernolepin, and vernolide induced apoptosis on HepG2 cells in a dose dependent manner and these effects correlated with G2/M phase cell cycle arrest. Our results indicated that vernodalin, vernolepin, and vernolide have potential to be used as lead compounds in the development of a therapeutic natural product for treatment of liver cancer.

Natural product-based design, synthesis and biological evaluation of 2',3,4,4'-tetrahydrochalcone analogues as antivitiligo agents.

A bioactive component, 2',3,4,4'-tetrahydrochalcone (RY3-a) was first isolated from Vernohia anthelmintica (L.) willd seeds, and a set of its analogs, RY3-a-1-RY3-a-15 and RY3-c were designed and synthesized. Biological activity assays showed that RY3-c exhibited better melanogenesis and antioxidant activity and lower toxicity in comparison with RY3-a and butin. Further study tests showed that RY3-c exhibited better melanogenesis activity compared with the positive control 8-methoxypsoralan (8-MOP) in a vitiligo mouse model, suggesting that RY3-c is a good candidate antivitiligo agent. Mechanistic studies showed that RY3-c could repair cell damage induced by excessive oxidative stress and may exert melanin synthesis activity in the mouse melanoma B16F10 cell line by activating the mitogen-activated protein kinase (MAPK) pathway and the upregulation of c-kit.