Distribution of phytoecdysteroids in the Caryophyllaceae

Phytoecdysteroids from Dioscorea dumetorum (Kunth) Pax. and their antioxidant and antidiabetic activities

Diabetes is a significant global health challenge, affecting circa 540 million adults worldwide. Dioscorea dumetorum, a Nigerian folkloric antidiabetic plant is severely understudied in terms of its bioactive phytochemical constituents. Antidiabetic guided isolation of the tubers and peels of D. dumetorum afforded three phytoecdysteroids bearing a cis-fused A/B ring junction including two new ones: 24-hydroxymuristerone A (1) and 24-hydroxykaladasterone (2), alongside the known muristerone A (3). Additionally, 2,2',7,7'-tetramethoxy-[1,1'-biphenanthrene]-4,4',6,6'-tetraol (4), batatasin I (5), and dihydroresveratrol (6) were isolated. Structural elucidation relied on spectroscopic, spectrometric methods, and comparison with existing literature. The ethyl acetate extracts of both the tubers and peels of D. dumetorum exhibited the highest phenolic content, correlating with potent antioxidant activity. Compounds 4 (IC50 = 0.10 mg/mL) and 6 (IC50 = 0.22 mg/mL) demonstrated superior inhibitory effects against α-glucosidase compared to acarbose (IC50 = 0.63 mg/mL). In contrast, compounds 3, 4, and 5 showed reduced α-amylase inhibition, with IC50 values of 2.58, 3.78, and 1.12 mg/mL, respectively, compared to acarbose (IC50 = 0.42 mg/mL). These observed bioactivities validate the traditional use of D. dumetorum and contribute valuable phytochemical data to the scientific literature of the species.

The Distribution of Phytoecdysteroids among Terrestrial Vascular Plants: A Comparison of Two Databases and Discussion of the Implications for Plant/Insect Interactions and Plant Protection

Phytoecdysteroids are a class of plant secondary compounds which are present in a wide diversity of vascular plant species, where they contribute to a reduction in invertebrate predation. Over the past 55 years, a significant body of heterogeneous literature on the presence, identities and/or quantities of ecdysteroids in plant species has accumulated, resulting in the compilation of a first database, the Ecdybase Literature Survey (ELS; 4908 entries, covering 2842 species). A second extensive database on the distribution of ecdysteroids in vascular plants is available as the Exeter Survey (ES; 4540 entries, covering 4155 species), which used standardised extraction and analysis methods to survey seeds/spores. We compare the usefulness of these two databases to provide information on the occurrence of phytoecdysteroids at the order/family levels in relation to the recent molecular classifications of gymnosperms, pteridophytes/lycophytes and angiosperms. The study, in conjunction with the other published literature, provides insights into the distribution of phytoecdysteroids in the plant world, their role in plant protection in nature and their potential future contribution to crop protection. Furthermore, it will assist future investigations in the chemotaxonomy of phytoecdysteroids and other classes of plant secondary compounds.

Determination of Flavonoids in Selected Scleranthus Species and Their Anti-Collagenase and Antioxidant Potential

A new 5,7-dihydroxy-3′-methoxy-4′-acetoxyflavone-8-C-β-d-arabinopyranoside-2″-O-(4‴-acetoxy)-glucoside (6) and three known flavone C-glycosides—5,7,3′,4′-tetrahydroxyflavone-6-C-xyloside-8-C-β-d-glucoside (lucenin-1) (7), 5,7,3′-trihydroxyflavone-6-C-glucoside-8-C-β-d-glucoside (vicenin-2) (8), and 5,7,4′-trihydroxy-3′-methoxyflavone-6-C-β-d-glucopyranoside-8-C-α-arabinopyranoside (chrysoeriol-6-C-β-d-glucopyranoside-8-C-α-arabinopyranoside) (9)—were isolated from aerial parts of Scleranthus perennis L. (Caryophyllaceae). Their structures were determined through the use of comprehensive spectroscopic and spectrometric methods, and a method for the quantification of the major constituents of S. perennis and S. annuus L. was developed. Furthermore, the anti-collagenase and antioxidant activities of all isolated compounds obtained from extracts and fractions from both Scleranthus species were evaluated. The highest percentage of collagenase inhibition (at 400 µg/mL) was distinguished for methanolic extracts (22.06%, 32.04%) and ethyl acetate fractions (16.59%, 14.40%) from S. annuus and S. perennis. Compounds 6–9 displayed moderate inhibitory activity, with IC₅₀ values ranging from 39.59–73.86 µM.

De Novo Transcriptome Assembly of Two Microsorum Fern Species Identifies Enzymes Required for Two Upstream Pathways of Phytoecdysteroids

Microsorum species produce a high amount of phytoecdysteroids (PEs), which are widely used in traditional medicine in the Pacific islands. The PEs in two different Microsorum species, M. punctatum (MP) and M. scolopendria (MS), were examined using high-performance liquid chromatography (HPLC). In particular, MS produces a high amount of 20-hydroxyecdysone, which is the main active compound in PEs. To identify genes for PE biosynthesis, we generated reference transcriptomes from sterile frond tissues using the NovaSeq 6000 system. De novo transcriptome assembly after deleting contaminants resulted in 57,252 and 54,618 clean transcripts for MP and MS, respectively. The clean Microsorum transcripts for each species were annotated according to gene ontology terms, UniProt pathways, and the clusters of the orthologous group protein database using the MEGAN6 and Sma3s programs. In total, 1852 and 1980 transcription factors were identified for MP and MS, respectively. We obtained transcripts encoding for 38 and 32 enzymes for MP and MS, respectively, potentially involved in mevalonate and sterol biosynthetic pathways, which produce precursors for PE biosynthesis. Phylogenetic analyses revealed many redundant and unique enzymes between the two species. Overall, this study provides two Microsorum reference transcriptomes that might be useful for further studies regarding PE biosynthesis in Microsorum species.

Small-scale analysis of phytoecdysteroids in seeds by HPLC-DAD-MS for the identification and quantification of specific analogues, dereplication and chemotaxonomy

INTRODUCTION

Phytoecdysteroids are analogues of arthropod steroids occurring in plants. They contribute to invertebrate deterrence. A wide diversity of ecdysteroids occurs in phytoecdysteroid-containing plant species, sometimes in high amounts. Ecdysteroids demonstrate potentially useful pharmaceutical actions in mammals.

OBJECTIVES

Establish reversed-phase high-performance liquid chromatography with tandem mass spectrometry (RP-HPLC-MS/MS) and RP-HPLC-DAD-MS (diode array detector mass spectrometry) methods for the separation, identification and quantification of ecdysteroids to screen for species containing significant amounts of 20-hydroxyecdysone (20E) and other useful ecdysteroids.

MATERIALS AND METHODS

Micro-extracts of seed samples (ca. 30 mg) in 50% ethanol were subjected to RP-SPE (solid-phase extraction) purification prior to analysis by RP-HPLC-MS/MS and RP-HPLC-DAD-MS. The method was initially applied to genera (Amaranthus, Centaurea, Lychnis, Ourisia, Serratula, Silene and Trollius) where high-accumulating species had been previously encountered. Seeds of 160 randomly selected species, many of which have not previously been assessed, were then analysed. HPLC-MS/MS with a short analysis time initially identifies ecdysteroid-positive extracts and quantifies 20E. The positive extracts (20 ng 20E) are then analysed by HPLC-MS/MS with a longer analysis time to identify and quantify 17 common phytoecdysteroids and, finally, HPLC-DAD-MS (0.1-0.25 μg 20E) is used to obtain UV- and MS-spectra to confirm identifications or as a basis for characterisation of partially identified or novel analogues.

RESULTS

Lychnis coronaria, Silene fimbriata and Silene hookeri ecdysteroids are characterised for the first time and those of Cucubalus baccifer and Ipheion uniflorum are more extensively characterised.

CONCLUSIONS

The procedure provides a rapid/sensitive method for screening small plant samples for the presence, quantification and identification of ecdysteroids. It permits ready dereplication of samples, identifying extracts containing large amounts or novel analogues.

Antihyperglycaemic, haemorheological and antioxidant activities of Lychnis chalcedonica L. extract in a streptozotocin-induced rat model of diabetes mellitus

Background New therapeutic strategies, such as the use of agents to correct rheological disorders, are needed for the prevention and treatment of angiopathy in diabetic patients. The aim of this work was to study the antihyperglycaemic, haemorheologic and antioxidant activities of an extract from the flowering plant Lychnis chalcedonica L. (ELC) and 20-hydroxyecdysone using the streptozotocin-induced model of diabetic rats. Methods The streptozotocin-induced model of diabetes was produced using streptozotocin at a dose of 50 mg/kg (ip). Animals from the experimental groups were treated with ELC (150 mg/kg) or 20-hydroxyecdysone (1.1 mg/kg) intragastrically in 1% aqueous starch mucilage daily, for 14 days; rats of control groups received an equal volume of starch mucilage. The following parameters were measured: glucose concentration (GC) in blood, whole blood viscosity (WBV), conjugated dienes in RBC membranes. Macro- and microrheological indicators (viz. plasma viscosity, haematocrit, RBC aggregation (T1/2) and the RBC elongation index (EI)) were additionally measured in rats that received ELC, and in the control group. Results After treatment with ELC, the GC in rats was 19% lower than that in the control group (14.7 ± 0.9 mM compared to 18.2 ± 1.1 mM). Rats with streptozotocin-induced diabetes have hyperviscosity syndrome, which is characterized by increased WBV, increased RBC aggregation and decreased deformability. ELC treatment reduced WBV at shear rates of 10-90 s-1 by 5-8%, and T1/2 and EI in the experimental group were 31% and 5-10% higher compared to the control group. 20-Hydroxyecdysone decreased WBV at shear rates of 10-90 s-1 by 3-11%. Finally, ELC and 20-hydroxyecdysone lowered the content of conjugated dienes by 27% and by 26% compared to the control groups. Conclusion In the streptozotocin-induced diabetic rat model, ELC showed measurable antihyperglycaemic activity; ELC and 20-hydroxyecdysone demonstrated similar haemorheological, and antioxidant activities.

Effect of methyl jasmonate on production of 20-hydroxyecdysone and turkesterone in hairy roots of Silene linicola C.C.Gmelin

Methyl jasmonate (MeJ) affects the regulation of secondary metabolism, and it is considered to be a promising elicitor in the culture of cells, tissues and plant organs. High-performance liquid chromatography method was used to identify the composition of ecdysteroids in hairy roots of Silene linicola. MeJ was found to have a stimulating effect on ecdysteroid biosynthesis in this culture. Addition of MeJ at a concentration of 100 μM increased the biosynthesis of 20-hydroxyecdysone by 74% (day 3), and that of turkesterone by 35% (day 6). The share of turkesterone in total ecdysteroid content in the investigated samples was up to 60%, and the content of 20-hydroxyecdysone was up to 30%. The study shows that MeJ is a promising stimulator of ecdysteroid biosynthesis in hairy roots of S. linicola.

Ecdysteroids: production in plant in vitro cultures

Ecdysteroids are secondary metabolites, widely distributed in the animal and plant kingdoms. They have a wide range of pharmacological effects in vertebrates, including mammals, most of which are beneficial for humans. Therefore, they have become compounds of interest for the pharmaceutical industry due to their adaptogenic, anabolic, hypoglycaemic, hypocholesterolaemic and antimicrobial activities, which are still being researched. Nowadays, ecdysteroids are present as active ingredients in bodybuilding supplements. Because of their complex structures, their chemical synthesis seems unprofitable and impractical. Due to high content of ecdysteroids in many plants, they are primarily obtained by extraction of the plant material. Plant in vitro cultures provide an alternative source of these compounds, helping to avoid problems associated with field production-such as variable yield or dependence on environmental factors, as well as limited availability of natural resources. Plant cell and tissue cultures may be suggested as alternatives for the production of plant biomass rich in pharmaceutically active ecdysteroids. Moreover, the use of common biotechnological strategies, such as elicitation or precursor feeding, may further increase the yield and improve production of these compounds. In this paper, we describe general information about ecdysteroids: their structure, biosynthesis, distribution, role in plants, and we review recent studies on micropropagation of ecdysteroid-producing plants and cell cultures, and potential ability of ecdysteroids enhancement in in vitro cultures.

Medicinal plants of the family Caryophyllaceae: a review of ethno-medicinal uses and pharmacological properties

Several species of the family Caryophyllaceae are widely used by many ethnic communities as traditional medicine throughout the world. The highest number of plants of the family are used in Chinese traditional medicine. The ethnopharmacologial studies of this family indicate that plants of the family possess anticancer, antibacterial, antifungal, antiviral, antioxidant, and anti-inflammatory properties. Other miscellaneous properties reported are ribosome inactivation properties, inhibition of prostatic enlargement in rats, and inhibition of intestinal enzyme carboxyelasterase in rats, cerebro-protective activity, and antiobesity in rats. Few reviews have been published yet, providing information regarding medicinal plants of the family and their biomedical properties. All published reviews have focused either on a particular taxa or a few species. The present review is focused on the traditional medicinal uses of the plants of the family Caryophyllaceae along with phytochemical and pharmacological studies of the family. A study of the literature revealed significant traditional medicinal importance of the family. Major chemical constituents of Caryophyllceae are saponins, Phytoecdysteroids, benzenoids, phenyl propanoids, and nitrogen containing compounds. The most important property of plants of the family is anticancer activity and is shown by the large number of plant species studied. This review of traditional medicinal and pharmacological uses of plants of the family, provide a ground for future research in the family.

Phytoecdysteroids of the East Asian Caryophyllaceae

BACKGROUND

Occurrence of integristerone A (1), 20-hydroxyecdysone (2), ecdysone (3), 2-deoxy-20-hydroxyecdysone (4) has been analyzed in 64 species of the East Asian Caryophyllaceae.

MATERIALS AND METHODS

Ecdysteroid content was determinate by high-performance liquid chromatography (HPLC). HPLC with a high-resolution mass spectrometry was performed on Shimadzu LCMS-IT-TOF (Japan) system equipped with a LC-20A Prominence liquid chromatograph, a photodiode array detector SPD-M20A and ion-trap/time-of-flight mass spectrometer.

RESULTS

New sources of phytoecdysteroids: Melandrium sachalinense and Melandrium firmum have been revealed. It is the 1(st) time that two has been identified in M. sachalinense and M. firmum; 1 in the species: Lychnis fulgens, Silene repens, Silene foliosa, Silene stenophylla, Silene jenisseensis and M. sachalinense; 3 in Lychnis cognata; 4 in L. fulgens, S. stenophylla and S. jenisseensis (the tribe Lychnideae, the subfamily Caryophylloideae). Ecdysteroid-negative taxa are Spergularia rubra of the tribe Sperguleae; species of the genera Minuartia, Honckenya, Eremogone, Arenaria, Moehringia, Pseudostellaria, Fimbripetalum, Stellaria and Cerastium of the tribe Alsineae; Scleranthus annuus of the tribe Sclerantheae, as well as the East Asian representatives of the genera Gypsophila, Psammophiliela, Dianthus and Saponaria of the tribe Diantheae; Oberna and Agrostemma of the tribe Lychnideae.

CONCLUSION

This investigation shows the most promising sources of ecdysteriods are species of genera Silene and Lychnis.

Diversity of Secondary Metabolites in the Genus Silene L. (Caryophyllaceae)—Structures, Distribution, and Biological Properties

The genus Silene (family Caryophyllaceae) comprises more than 700 species, which are widely distributed in temperate zones of the Northern Hemisphere, but are also present in Africa and have been introduced in other continents. Silene produces a high diversity of secondary metabolites and many of them show interesting biological and pharmacological activities. More than 450 compounds have been isolated; important classes include phytoecdysteroids (which mimic insect molting hormones), triterpene saponins (with detergent properties), volatiles, other terpenoids and phenolics. This review focusses on the phytochemical diversity, distribution of Silene secondary metabolites and their biological activities.

A new iced tea base herbal beverage with Spergularia rubra extract: metabolic profile stability and in vitro enzyme inhibition

Beverages are an ideal format to offer nutrients, specific health-promoting functionality, and desirable sensory attributes to consumers. Taking into account previous research on Spergularia rubra (L.) J. Presl & C. Presl, the aim of this work was to describe the chemistry and biochemistry associated with the production of a new iced tea base herbal beverage containing a hydroethanolic extract of this species, including both naturally occurring and added components. Phenolic compounds of S. rubra hydroethanolic extract and of the iced tea base herbal beverage were determined by HPLC-DAD. Thirty compounds, comprising nonacylated C-glycosyl flavones, C-glycosyl flavones acylated with aromatic acids, and C-glycosyl flavones acylated with aliphatic acids, were identified, being essentially represented by apigenin derivatives. Organic acids of both samples were determined by HPLC-UV, malic acid being the major one. A strong inhibition of α-glucosidase, acetylcholinesterase, and butyrylcholinesterase was observed. Furthermore, the influence of the pH of the digestive tube on the chemical composition of both extract and iced tea base herbal beverage and, consequently, on their biological activity, was assessed. In a general way, pH variation significantly decreased (p < 0.05) the metabolites content and enzymes inhibitory capacity. Nevertheless, the beverage enriched with S. rubra extract represents a valuable addition to consumer's health and nutrition, once the loss of activity is lower than the one verified for the base iced tea. Thus, the results suggest that the ingestion of this beverage could be of potential interest for several chronic disorders, particularly Alzheimer's disease.

The phytoecdysteroid profiles of 7 species of Silene (Caryophyllaceae)

The phytoecdysteroid profiles of extracts of aerial parts of flowering plants of 7 ecdysteroid-containing species in the genus Silene (Caryophyllaceae; S. fridvaldszkyana Hampe, S. gigantea L., S. graminifolia Otth, S. mellifera Boiss. & Reuter, S. repens Patr., S. schmuckeri Wettst., and S. sendtneri Boiss.) have been examined and identified by HPLC and, in the case of two new compounds, by mass spectrometry and NMR. S. frivaldszkyana was found to contain predominantly 20-hydroxyecdysone (20E), with smaller amounts of 2-deoxyecdysone (2dE), 2-deoxy-20-hydroxyecdysone (2d20E), polypodine B (polB), integristerone A (IntA), 26-hydroxypolypodine B (26polB), and 20,26-dihydroxyecdysone (20,26E). Additionally, a new minor ecdysteroid, 26-hydroxyintegristerone A, has been identified from this species. S. gigantea contains 3 major ecdysteroids (2dE, 2d20E, and 20E) and much smaller amounts of intA and 2-deoxy-20-hydroxyecdysone 25-beta-D-glucoside, which is a new ecdysteroid. Ecdysteroids in the other 5 species have been identified by co-chromatography with reference compounds on RP- and NP-HPLC systems. There is considerable variability with regard to ecdysteroid profiles within the genus Silene. The chemotaxonomic value of ecdysteroid profiles within the genus Silene is discussed.

The Karlson Lecture. Phytoecdysteroids: what use are they?

Phytoecdysteroids are analogues of arthropod steroid hormones found in plants, where they deter predation by non-adapted predators. There is potential to exploit this to develop new strategies for pest control, either by using ecdysteroids as lead molecules for the design of novel pest control agents or by alteration of ecdysteroid levels/profiles in crop plants through plant breeding or genetic modification. However, it is other properties of phytoecdysteroids that have led to a rapid recent increase in scientific and commercial interest in these molecules. They are apparently non-toxic to mammals and a wide range of beneficial pharmacological (adaptogenic, anabolic, anti-diabetic, hepatoprotective, immunoprotective, wound-healing, and perhaps even anti-tumour) activities is claimed for them. In particular, this has led to a large (and unregulated) market for ecdysteroid-containing preparations for body-builders, sportsmen, and pets, among others. Ecdysteroids are also being considered as nutraceutical additives to food products. Further, ecdysteroids are good candidates as elicitors for gene-switch systems to be used in medical gene therapy and research applications. In this article, I review the applications of phytoecdysteroids and assess their future potential.

Preliminary phytochemical investigation of Lychnis flos-cuculi herbs

Five polyphenolic compounds were identified from the diethyl ether and ethyl acetate extracts of the herb of ragged robin, Lychnis flos-cuculi L. (Caryophyllaceae). The identified and isolated compounds were established as a caffeic acid, luteolin, apigenin, apigenin 8-C-beta-D-glucopyranoside (vitexin) and luteolin 8-C-beta-D-glucopyranoside (orientin) by means of extensive spectroscopic studies, including UV and NMR, and confirmed by their chromatographic behavior--TLC and HPLC analyses. This is the first report of occurrence of these compounds in L. flos-cuculi.

New Minor Ecdysteroids from Silene viridiflora

Two new minor ecdysteroids, the 2,22- and 3,22-diacetates of 20,26-dihydroxyecdysone have been isolated from the aerial part of Silene viridiflora L. (Caryophyllaceae).