New coumarin from the roots of Prangos pabularia

Chemical profile of the roots of Clausena lansium and their inhibitory effects of the over-activation in BV-2 microglial cells

From the 95% ethanol aqueous extract of the roots of Clausena lansium, six previously undescribed alkaloids (1, 2a, 2b, 15, 24a, 24b), a pair of prenylated phenylpropenols (26a, 26b), two coumarins (27, 28), and two undescribed sesquiterpenes (37, 38) were isolated and identified using spectroscopic and electron circular dichroism data, together with thirty-two known compounds. The absolute configurations of three alkaloids (3a, 3b, 4a) were determined for the first time. In vitro assay showed that alkaloids 7, 10, 12, 19, and furanocoumarins 34, 35 displayed inhibitory effects on the production of nitric oxide in lipopolysaccharide (LPS)-induced BV-2 microglial cells, which were stronger than that of the minocycline (positive control). RT-PCR results indicated that indizoline (7) could inhibit the expression of pro-inflammatory factors (IL-1β, TNF-α, and IL-6) in LPS-treated BV-2 cells.

Isolation, characterization and evaluation of oxypeucedanin and osthol from local endemic Prangos aricakensis Behçet and Yapar root as antioxidant, enzyme inhibitory, antibacterial and DNA protection: molecular docking and DFT approaches

Prangos species were previously used against many disorders due to their chemical component. Prangos aricakensis Behçet & Yapar is a newly discovered local endemic species in Turkey's eastern region, and there is no research on P. aricakensis in the literature. In this work, oxypeucedanin and osthol molecules have been isolated from the root part of P. aricakensis for the first time. Oxypeucedanin and osthol structures were elucidated by 1D and 2D NMR analysis. For the bioactivities determination, antioxidant (DPPH· and ABTS·+ scavenging), enzyme inhibition (AChE, BChE, tyrosinase, and urease), antibacterial and DNA protection activity studies were applied for both molecules and compared with standard drug molecules, after applying enzyme kinetic assays and in silico approaches to clarify the mechanism of action for both molecules with enzymes, using molecular docking and density functional theory (DFT). Oxypeucedanin (2.19 ± 0.38 µg/mL) and osthol (4.57 ± 1.28 µg/mL) exhibited better activity than standards in DPPH∙ scavenging activity. Osthol (11.76 ± 0.59 µg/mL) showed a better tyrosinase inhibition effect than kojic acid (12.82 ± 0.91 µg/mL), and oxypeucedanin (3.03 ± 0.01 µg/mL) showed better urease inhibition effect than thiourea (5.37 ± 1.86 µg/mL). Our results showed that the osthol molecule was an excellent skin protective agent while the oxypeucedanin molecule could be a remarkable antiulcer agent. Therefore, although this study is the first in its field, it remained in the in vitro and in silico stages and is thought to pave the way for in vivo studies in the future.Communicated by Ramaswamy H. Sarma.

New coumarin from the roots of Prangos pabularia growing wild in Tajikistan

Dichloromethane and butanol extracts of the roots of Prangos pabularia were analyzed to determine chemical constituents and biological activity. The new coumarin 1, yuganin B ((5-(((2S,3R,4S,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-((2-oxo-2H-chromen-7-yl)oxy)tetrahydro-2H-pyran-3-yl)oxy)-3,4-dihydroxytetrahydrofuran-3-yl)methyl 4-hydroxy-3-methoxybenzoate) along with three phenolic and twenty-four known coumarins were isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by UV, HR-ESIMS, and 1 D and 2 D NMR spectroscopy. In addition, the anti-melanogenic effect of several of the isolated individual compounds and their inhibitory effect on B16 cells were evaluated. Isolating and testing compounds may proof to be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.

Mechanisms of anti-ulcer actions of Prangos pabularia (L.) in ethanol-induced gastric ulcer in rats

Peptic ulcer disease is the greatest digestive disorder that has increased incidence and recurrence rates across all nations. Prangos pabularia (L.) has been well documented as a folkloric medicinal herb utilized for multiple disease conditions including gastric ulcers. Hence, the target study was investigation the gastro-protection effects of root extracts of Prangos pabularia (REPP) on ethanol-mediated stomach injury in rats. Sprague Dawley rats were clustered in 5 cages: A and B, normal and ulcer control rats pre-ingested with 1 % carboxymethyl cellulose (CMC)); C, reference rats had 20 mg/kg omeprazole; D and E, rats pre-supplemented with 250 and 500 mg/kg of REPP, respectively. After one hour, group A was given orally 1 % CMC, and groups B-E were given 100 % ethanol. The ulcer area, gastric acidity, and gastric wall mucus of all stomachs were determined. The gastric tissue homogenates were examined for antioxidant and MDA contents. Moreover, the gastric tissues were analyzed by histopathological and immunohistochemically assays. Acute toxicity results showed lack of any toxic effects or histological changes in rats exposed to 2 and 5 g/kg of REPP ingestion. The ulcer controls had extensive gastric mucosal damage with lower gastric juice and a reduced gastric pH. REPP treatment caused a significant reduction of the ethanol-induced gastric lacerations represented by an upsurge in gastric mucus and gastric wall glycoproteins (increased PAS), a decrease in the gastric acidity, leukocyte infiltration, positively modulated Bax and HSP 70 proteins, consequently lowered ulcer areas. REPP supplementation positively modulated oxidative stress (increased SOD, CAT, PGE2, and reduced MDA) and inflammatory cytokines (decreased serum TNF-α, IL-6, and increased IL-10) levels. The outcomes could be scientific evidence to back-up the folkloric use of A. Judaica as a medicinal remedy for oxidative stress-related disorders (gastric ulcer).

New coumarin glycosides from endemic Prangos heyniae H. Duman & M.F. Watson

Two new coumarin glycosides, named 7-methoxy isoarnottinin 4'-O-β-ᴅ-glucopyranoside and 7-methoxy isoarnottinin 4'-O-rutinoside (1 and 2) along with six known compounds (3-8) were isolated from the roots of Prangos heyniae, an endemic plant of Turkey. 1-methylethyl 6-O-D-apio-β-ᴅ-furanosyl-β-ᴅ-glucopyranoside (7) and cnidioside A (8) have been obtained from the genus Prangos for the first time. Structures of isolated compounds were established using spectroscopic methods (1 D and 2 D NMR, HR-MS, UV and IR). Moreover, all extracts and isolated compounds were evaluated for their cytotoxic activity against NIH/3T3, HK-2, A-549, MCF-7, PC-3 and SH-SY5Y cell lines by WST-1 method. One of the new coumarin glycosides, 7-methoxy isoarnottinin 4'-O-β-ᴅ-glucopyranoside (1) exhibited selective cytotoxic activity against SH-SY5Y cells with IC₅₀ value of 31.41 ± 1.04 μM.

Phytochemical Screening, Antioxidant, and Enzyme Inhibitory Properties of Three Prangos Species (P. heyniae, P. meliocarpoides var. meliocarpoides, and P. uechtritzii) Depicted by Comprehensive LC-MS and Multivariate Data Analysis

The aim of the present study was to identify/quantify bioactive compounds and determine the antioxidant activity and enzyme inhibitory effects of various solvent extracts (n-hexane, ethyl acetate, methanol, and water) of Prangos heyniae H. Duman and M.F. Watson, Prangos meliocarpoides var. meliocarpoides, and Prangos uechtritzii Boiss. and Hausskn. This is the first time such a report has been designed to validate the phytochemical composition and bioactivity (especially enzyme inhibitory properties) of these plants. A combined approach of liquid chromatography (LC) with mass spectrometry (HR-MS and MSⁿ) allowed to identify that P. heyniae contains condensed tannins; P. meliocarpoides is rich in hydrolysable tannins; and P. uechtritzii possesses coumarins, flavonoids, and hydroxycinnamic acids. Different extracts were tested for antioxidant activities using a battery of assays, such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), total antioxidant capacity (TAC) (phosphomolybdenum), and metal chelating. Enzyme inhibitory effects were investigated using acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase as target enzymes. The obtained results depended on the extraction solvents used for each Prangos species. The methanol extract of P. meliocarpoides var. meliocarpoides exhibited significant radical scavenging activity (DPPH: 52.27 mg Trolox equivalent (TE)/g; ABTS: 92.84 mg TE/g), the most potent-reducing potential (CUPRAC: 154.04 mg TE/g; FRAP: 104.34 mg TE/g), and high TAC (2.52 mmol TE/g). Moreover, the strongest BChE (7.97 mg galantamine equivalent/g), α-amylase (0.46 mmol acarbose equivalent/g), and tyrosinase (81.15 mg kojic acid equivalent/g) inhibitory effects were observed for the hexane extract of P. meliocarpoides var. meliocarpoides. Correlation analysis showed a significant positive correlation between hydrolysable tannins and antioxidant activities. The same trend was also observed between the same class of compounds and the inhibitory effects on enzymatic activities. These results suggest a principal role of hydrolysable tannins in the observed bioactivities of Prangos. Our results suggested that the tested Prangos species could be valuable as sources of natural agents in the development of health-promoting applications.

Chemical Composition, Biological Activities and In Silico Analysis of Essential Oils of Three Endemic Prangos Species from Turkey

In this study, the essential oils (EOs) obtained from three endemic Prangos species from Turkey (P. heyniae, P. meliocarpoides var. meliocarpoides, and P. uechtritzii) were studied for their chemical composition and biological activities. β-Bisabolenal (12.2%) and caryophyllene oxide (7.9%) were the principal components of P. heyniae EO, while P. meliocarpoides EO contained sabinene (16.7%) and p-cymene (13.2%), and P. uechtritzii EO contained p-cymene (24.6%) and caryophyllene oxide (19.6%), as the most abundant components. With regard to their antioxidant activity, all the EOs were found to possess free radical scavenging potential demonstrated in both DPPH and ABTS assays (0.43–1.74 mg TE/g and 24.18–92.99 mg TE/g, respectively). Additionally, while no inhibitory activity was displayed by P. meliocarpoides and P. uechtritzii EOs against both cholinesterases (acetyl- and butyryl-cholinesterases). Moreover, all the EOs were found to act as inhibitors of tyrosinase (46.34–69.56 mg KAE/g). Molecular docking revealed elemol and α-bisabolol to have the most effective binding affinity with tyrosinase and amylase. Altogether, this study unveiled some interesting biological activities of these EOs, especially as natural antioxidants and tyrosinase inhibitors and hence offers stimulating prospects of them in the development of anti-hyperpigmentation topical formulations.

Comparative evaluation of relaxant effects of three prangos species on mouse corpus cavernosum: Chemical characterization and the relaxant mechanisms of action of P. pabularia and (+)-oxypeucedanin

ETHNOPHARMACOLOGICAL RELEVANCE

Erectile dysfunction (ED) is the most common form of sexual dysfunction which has been the topic of great interest through the history by all cultures. It is now among the most treated health problems in men of all ages that develop under the influence of lifestyle factors and some diseases. Plants are extensively used to cure sexual dysfunction for centuries. Roots of Prangos sp. have been used to improve sexual performance in Anatolian traditional medicine and are rich of coumarin, furanocoumarin and their derivatives. Scientific research is necessary to support and validate the ethno-traditional uses of these plants.

AIM OF THE STUDY

The aim of this study is to investigate the effects of the root extracts of P. pabularia, P. uechtritzii and P. heyniae on erectile function and to isolate and identify the chemical compounds of the most active extract and reveal possible pharmacological mechanism of the major compound of the extract with the strongest relaxant effect in mouse corpus cavernosum (MCC).

MATERIALS AND METHODS

The roots of plants were extracted with chloroform, n-hexane and methanol. The compounds were isolated from the extract by column chromatography and structures were identified by NMR and MS. The relaxant effects of extracts (10^-7-10^-4 g/mL), (+)-oxypeucedanin (10^-7-10^-4 M) and Na₂S (10^-7-3 × 10^-3 M) were tested in MCC strips by DMT myograph. To investigate the mechanism, the synthesis inhibitors of aminooxyacetic acid (AOAA, 10^-2 M) and nitro-L-arginine methyl ester (L-NAME, 10^-4 M) were used, respectively. H₂S formation was evaluated basal and L-cysteine (L-cyst)-stimulated conditions by H₂S microsensor.

RESULTS

All extracts relaxed MCC in a concentration dependent manner. The maximum relaxing effects were achieved with chloroform extracts. Chloroform extract of P. pabularia (Pp-CE) was more potent than the others. Pp-CE-induced relaxations were significantly decreased by AOAA and L-NAME. (+)-Oxypeucedanin, the major compound of Pp-CE, induced relaxant responses and this effect was inhibited by AOAA, but not L-NAME. The relaxation of (+)-oxypeucedanin was found to be similar in view of E_max to positive control H₂S donor Na₂S. (+)-Oxypeucedanin increased L-cyst-stimulated H₂S formation. Augmentation of H₂S synthesis with (+)-oxypeucedanin was inhibited by AOAA.

CONCLUSIONS

Pp-CE has the strongest effect on relaxation of MCC and this result supports the traditional aphrodisiac use of P. pabularia root extract in Anatolia. The pharmacological mechanisms of Pp-CE to relax MCC involve NO and H₂S formation. (+)-Oxypeucedanin could be responsible for the H₂S-mediated relaxations of Pp-CE in MCC.

Oxypeucedanin: Chemotaxonomy, Isolation, and Bioactivities

The present review comprehensively gathered phytochemical, bioactivity, and pharmacokinetic reports on a linear furanocoumarin, namely oxypeucedanin. Oxypeucedanin (OP), which structurally contains an epoxide ring, has been majorly isolated from ethyl acetate-soluble partitions of several genera, particularly Angelica, Ferulago, and Prangos of the Apiaceae family; and Citrus, belonging to the Rutaceae family. The methanolic extract of Angelica dahurica roots has been analytically characterized as the richest natural OP source. This naturally occurring secondary metabolite has been described to possess potent antiproliferative, cytotoxic, anti-influenza, and antiallergic activities, as assessed in preclinical studies. In order to explore potential drug candidates, oxypeucedanin, its derivatives, and semi-synthetically optimized analogues can be considered for the complementary assessments of biological assays.

Separation and anti-inflammatory evaluation of phytochemical constituents from Pleurospermum candollei (Apiaceae) by high-speed countercurrent chromatography with continuous sample load

Pleurospermum (Apiaceae) species possess a wide range of biological properties viz. analgesic, anti-inflammatory, antimalarial, and so on. Pleurospermum candollei (DC.) Benth. Ex C. B. Clark. is reported to cure diarrhea, gastric, respiratory, stomach, abdominal, joint, and back pain problems. In addition, it is also used for both male and female infertility. The present study deals with an efficient technique using high-speed countercurrent chromatography for separation of chemical components from the methanol extract of P. candollei. Notably, nine main compounds namely luteolin 7-O-glucoside (1), oxypeucedanin hydrate (2), pabulenol (3), bergapten (4), heptadecanoic acid (5), (E)-isoelemicin (6), trans-asarone (7), α-linolenic acid (8), and isoimperatorin (9) were very efficiently separated and isolated in pure form. Multiple injections were applied followed by two off-line recycling high-speed countercurrent chromatography. The inhibitory effect of nitric oxide production of all compounds was tested in the presence of 200 ng/mL lipopolysaccharide in RAW264.7 mice macrophage cells. The results demonstrated that compounds 7 and 8 effectively inhibited nitric oxide production, with IC₅₀ values of 28.44 and 53.18 μM, respectively. This study thus validates the traditional claim of using P. candollei. Taken together, these findings will be useful in future research to find a potential candidate with anti-inflammatory properties.

The celery genome sequence reveals sequential paleo-polyploidizations, karyotype evolution and resistance gene reduction in apiales

Celery (Apium graveolens L. 2n = 2x = 22), a member of the Apiaceae family, is among the most important and globally grown vegetables. Here, we report a high-quality genome sequence assembly, anchored to 11 chromosomes, with total length of 3.33 Gb and N50 scaffold length of 289.78 Mb. Most (92.91%) of the genome is composed of repetitive sequences, with 62.12% of 31 326 annotated genes confined to the terminal 20% of chromosomes. Simultaneous bursts of shared long-terminal repeats (LTRs) in different Apiaceae plants suggest inter-specific exchanges. Two ancestral polyploidizations were inferred, one shared by Apiales taxa and the other confined to Apiaceae. We reconstructed 8 Apiales proto-chromosomes, inferring their evolutionary trajectories from the eudicot common ancestor to extant plants. Transcriptome sequencing in three tissues (roots, leaves and petioles), and varieties with different-coloured petioles, revealed 4 and 2 key genes in pathways regulating anthocyanin and coumarin biosynthesis, respectively. A remarkable paucity of NBS disease-resistant genes in celery (62) and other Apiales was explained by extensive loss and limited production of these genes during the last ~10 million years, raising questions about their biotic defence mechanisms and motivating research into effects of chemicals, for example coumarins, that give off distinctive odours. Celery genome sequencing and annotation facilitates further research into important gene functions and breeding, and comparative genomic analyses in Apiales.

Sortase A-Inhibitory Coumarins from the Folk Medicinal Plant Poncirus trifoliata

Thirteen coumarins (1-13), including five new compounds (1-5), were isolated from the folk medicinal plant Poncirus trifoliata. Combined spectroscopic analyses revealed that coumarins 1-4 are bis-isoprenylated coumarins with diverse oxidation patterns, while 5 is an enantiomeric di-isoprenylated coumarin. The absolute configurations of the stereogenic centers in the isoprenyl chains were assigned through MTPA and MPA methods, and those of the known compounds triphasiol (6) and ponciol (7) were also assigned using similar methods. These coumarins inhibited significantly Staphylococcus aureus-derived sortase A (SrtA), a transpeptidase responsible for anchoring surface proteins to the peptidoglycan cell wall in Gram-positive bacteria. The present results obtained indicated that the bioactivity and underlying mechanism of action of these coumarins are associated with the inhibition of SrtA-mediated S. aureus adhesion to eukaryotic cell matrix proteins including fibrinogen and fibronectin, thus potentially serving as SrtA inhibitors.

The Prangos genus: a comprehensive review on traditional use, phytochemistry, and pharmacological activities

The members of the Prangos genus (Apiaceae) have been widely applied in the Iranian traditional medicine internally and externally for different purposes. The aim of this review is to summarize the ethnomedicinal and food applications of Prangos species and to gather the phytochemical and pharmacological data on this genus. Among the 129 constituents isolated from Prangos species, coumarin derivatives are the main compounds. Several papers report the compositions of essential oils obtained from different plant parts, mostly containing monoterpene and sesquiterpene hydrocarbons. Various pharmacological activities of essential oils, crude extracts or isolated compounds of the Prangos species have been observed, primarily in in vitro experiments. Antioxidant, antimicrobial, cytotoxic and anti-proliferative activities have been the most extensively studied. The efficacy and safety of Prangos plants have not been assessed in animal experiments or clinical trials. Although their furocoumarin content might be a source of adverse effects, toxic effects of Prangos species have not been reported. It can be concluded, that further preclinical and clinical data are necessary to assess the rationale and safety of the medicinal and food use of Prangos species.

Volatile Secondary Metabolites with Potent Antidiabetic Activity from the Roots of Prangos pabularia Lindl.—Computational and Experimental Investigations

(1) Background: Almost 500 million people worldwide are suffering from diabetes. Since ancient times, humans have used medicinal plants for the treatment of diabetes. Medicinal plants continue to serve as natural sources for the discovery of antidiabetic compounds. Prangos pabularia Lindl. is a widely distributed herb with large reserves in Tajikistan. Its roots and fruits have been used in Tajik traditional medicine. To our best knowledge, there are no previously published reports concerning the antidiabetic activity and the chemical composition of the essential oil obtained from roots of P. pabularia. (2) Methods: The volatile secondary metabolites were obtained by hydrodistillation from the underground parts of P. pabularia growing wild in Tajikistan and were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Protein tyrosine phosphatase 1B (PTP-1B) inhibition assay and molecular docking analysis were carried out to evaluate the potential antidiabetic activity of the P. pabularia essential oil. (3) Results: The main constituents of the volatile oil of P. pabularia were 5-pentylcyclohexa-1,3-diene (44.6%), menthone (12.6%), 1-tridecyne (10.9%), and osthole (6.0%). PTP-1B inhibition assay of the essential oil and osthole resulted in significant inhibitory activity with an IC50 value of 0.06 ± 0.01 and 0.93 ± 0.1 μg/mL. Molecular docking analysis suggests volatile compounds such as osthole inhibit PTP-1B, and the results are also in agreement with experimental investigations. (4) Conclusions: Volatile secondary metabolites and the pure isolated compound (osthole) from the roots of P. pabularia exhibited potent antidiabetic activity, twenty-five and nearly two times more than the positive control (3-(3,5-dibromo-4-hydroxybenzoyl)-2-ethylbenzofuran-6-sulfonic acid-(4-(thiazol-2-ylsulfamyl)-phenyl)-amide)) with an IC50 value of 1.46 ± 0.4 μg/mL, respectively.