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Two new iridoids (1, 2), along with one known iridoid (3), two known triterpenoid saponins (4, 5), and one known flavonoid (6), were isolated from the whole plant of Patrinia heterophylla Bunge. Their structures were elucidated on the basis of extensive spectroscopic data analysis, especially by means of 1D and 2D NMR and HR-ESI-MS analyses. The cytotoxic activity of the isolated compounds against human leukemic cells was evaluated using CCK-8 assay. Compounds 1 and 2 showed cytotoxic activities against HL-60, K562, and Jurkat cells, and compounds 3 and 5 showed cytotoxic activity against HL-60. Among them, compound 1 showed slightly stronger cytotoxic activity against K562 cells than the positive control.

Lonimacranaldes A and B (1 and 2), along with one biogenetically related intermediate, lonimacranalde C (3), were isolated from the flower buds of Lonicera macranthoides. Characterized by an iridoid structure and an additional C-6 unit with an aldehyde group, compounds 1 and 2 are the first examples of hybrid iridoids possessing an unexpected 6/5/6 fused tricyclic ring system, while compound 3 serves as an important precursor for their generation. The structures of lonimacranaldes A–C (1–3) were revealed by extensive spectroscopic and X-ray diffraction analyses. A plausible biogenetic pathway for them was proposed. Compound 3 showed anti-inflammatory activities by inhibiting the production of IL-6 on LPS-induced RAW 264.7 cells with an IC50 value of 6.33 μM.

Ethnopharmacological relevance The Vha-Venda people living in rural areas of Limpopo Province of South Africa regularly use traditional plant-based medicines to treat malaria. In our earlier publication, twenty indigenous plant species used to treat malaria or its symptoms by Vha-Venda people were evaluated for antiplasmodial activity. The main objective of the current study was to assess the robustness of NMR-based metabolomics in discriminating classes of secondary compounds that are responsible for the observed antimalarial activity and the isolation of antiplasmodial compounds. Materials and methods Twenty dichloromethane extracts were reconstituted in CDCl3, subjected to 1H NMR-based metabolomic analysis on a Varian 600 MHz spectrometer and the acquired 1H NMR spectra were then evaluated collectively using multivariate data analysis (MDA). Principal Component Analysis (PCA) and Orthogonal Projections to Latent Structures–Discriminant Analysis (OPLS-DA) were used to ‘globally’ discern antiplasmodial profiles. A contribution plot was then generated from the OPLS-DA scoring plot in an attempt to determine the classes of compounds that are responsible for the observed grouping. Further phytochemical analyses were conducted on the lipophilic extracts of Tabernaemontana elegans and Vangueria infausta subsp. infausta. These best candidates were fractionated, purified and their isolated compounds identified based on conventional chromatographic and spectroscopic techniques. Results The PCA did not separate the acquired profiles according to the detected antiplasmodial bioactivity. Application of a supervised OPLS-DA on the 1H NMR profiles resulted in a discrimination pattern that could be correlated to the observed antimalarial bioactivity. A contribution plot generated from the OPLS-DA scoring plot illustrated the classes of compounds responsible for the observed grouping. Prominent peaks were observed in the aromatic, sugar-based/N-containing and aliphatic spectral regions of the contribution plot. Two known indole alkaloids were isolated from T. elegans, and identified as tabernaemontanine (IC50 = 12.0 ± 0.8 µM) and dregamine (IC50 = 62.0 ± 2.4 µM). Friedelin (IC50 = 7.20 ± 0.5 µM) and morindolide (IC50 = 107.1 ± 0.6 µM) were isolated from V. infausta subsp. infausta. This is the first report of the rare iridoid lactone, morindolide's antimalarial activity. While these two compounds have been previously identified, this is the first account of their occurrence in the genus Vangueria. Conclusion The study illustrated the potential of NMR-based metabolomics in discriminating classes of compounds that may be attributed to antiplasmodial activity. Additionally, the study demonstrated the potential of discovering novel antiplasmodial scaffolds from medicinal plants and the rationale for the bioprospecting antimalarial plant species used by Vha-Venda people.

A simple and modular one-step synthesis of diversely substituted pyridines from readily available α,β-unsaturated carbonyl compounds and propargylic amines has been developed. The present protocol has a broad substrate scope and allows access to multi-substituted pyridines with select control of the substitution pattern under mild and metal-free conditions. The reaction involves imine formation followed by concomitant cyclization through an allenyl intermediate to afford pyridines in excellent yields, with water as the sole by-product. This mild strategy is also suitable for functionalization of natural products or other advanced intermediates having α,β-unsaturated carbonyl functionality. The utility of the present protocol was showcased with the synthesis of the monoterpene alkaloid, (-)-actinidine, an ant-associated iridoid.

Narjatamanins A (1) and B (2), a pair of epimers possessing a novel 2,3-seco-iridoid skeleton with an unusual 1,10-oxygen bridge, were isolated from the whole plants of Nardostachys jatamansi. Their structures were elucidated by a combination of various spectroscopic methods, including HRESIMS, IR and 1D and 2D NMR techniques. The absolute configurations of 1 and 2 were established by electronic circular dichroism (ECD) calculations. The pharmacological activities of 1 and 2 to alleviate AD-like symptoms were also evaluated using the Caenorhabditis elegans Alzheimer's disease (AD) pathological model, and narjatamanins A (1) and B (2) showed statistically significant delay in the worm paralysis phenotype of AD-like symptoms.

Background Although fruit and vegetable-rich diets have beneficial effects on cardiovascular diseases, we have little knowledge of the impact of fruits and their constituents, iridoids and anthocyanins, on the l -arginine-ADMA-DDAH pathway. Our previous study demonstrated the modulation of those factors by the oral administration of the cornelian cherry fruit. Hypothesis/purpose We have assessed the effects of the oral administration of two main constituents isolated from the cornelian cherry fruit, iridoid loganic acid and anthocyanins, on l -arginine, its derivatives (ADMA, SDMA), metabolites (DMA, l -citrulline), and the hepatic DDAH activity and its isoform expression in rabbits fed a high-cholesterol diet. We have also analyzed eNOS expression in the thoracic aorta as well as the redox status in blood. Study Design In the present study, we used an animal model of diet induced atherosclerosis. For 60 days, white New Zealand rabbits were fed a standard diet, a 1% cholesterol enriched diet, or concomitantly with the investigated substances. l -arginine, ADMA, SDMA, DMA, and l -citrulline were assessed using the LC-MS/MS method. DDAH activity and redox parameters were analyzed spectrophotometrically. DDAH1 and DDAH2 isoform expressions were assessed by western blotting, mRNA expression of eNOS was quantified by real-time PCR. Results We demonstrated that the administration of loganic acid (20 mg/kg b.w.), and to a lesser extent of anthocyanins (10 mg/kg b.w.), caused an increase in the l -arginine level and the l -arginine/ADMA ratio. Also, both substances decreased ADMA, DMA, and l -citrulline, but not SDMA levels. Anthocyanins, but not loganic acid, enhanced the activity of DDAH in the liver. Anthocyanins also significantly enhanced both DDAH1 and DDAH2 expression, while loganic acid to a lesser extent enhanced DDAH1 but not DDAH2 expression. Both loganic acid and anthocyanins pronouncedly increased mRNA expression of eNOS in thoracic aortas. Both loganic acid and anthocyanins reversed the blood glutathione level depleted by dietary cholesterol. Cholesterol feeding decreased the blood GPx level, and the change was not reversed by anthocyanins or loganic acid. We did not observe any significant differences in the blood levels of MDA or SOD among the groups. Conclusion Iridoids and anthocyanins may modulate the l -arginine-ADMA pathway in subjects fed a high-cholesterol diet.

Three phenylpropanoid-conjugated iridoid glucosides, acetylgaertneric acid (1), acetyldehydrogaertneroside (2), and dehydrogaertneric acid (10), together with nine known related iridoid glucosides (3–9, 11, and 12), two coumaroyl alkaloids, one benzenoid, and three flavonoid glucosides were isolated from leaves of Morinda morindoides (Rubiaceae). Structures of these isolated compounds were determined using spectroscopic analysis. Compounds 1–18 and previously isolated compounds (19–29) were evaluated for anti-trypanosomal activity against Trypanosoma cruzi Tulahuen strain (trypomastigote and amastigote) together with cytotoxicity against host cells, new-born mouse heart cells. Among them, molucidin (21) and prismatomerin (22) exhibited good anti-trypanosomal activity (IC50 of 4.67 and 5.70 µM, respectively), together with cytotoxicity (CC50 of 2.76 and 3.22 μM, respectively). Compounds 1–18 did not show anti-malarial activity against a chloroquine/mefloquine-sensitive strain of Plasmodium falciparum.

The aim of the research was the analysis of yoghurts enriched with blue honeysuckle berries dry polyphenolic extract and new preparation of resistant starch. The additives were introduced individually at concentration 0.1% (w/v) and in mixture at final concentration of 0.1 and 0.2% of both components. Yogurt microflora, pH, and its physicochemical and antioxidant properties were examined over 14 days of storage under refrigerated conditions. Studies showed that both substances can be successfully used in yoghurt production. Yoghurt microflora es. S. thermophilus and Lb. delbrueckii subsp. bulgaricus counts appeared to be higher in samples supplemented with these additives comparing to control yoghurt by 3–8%. More stimulating effect on their growth, especially on S. thermophilus, revealed resistant starch. Addition of this polysaccharide improved also the rheological properties of yogurts, which showed higher viscosity than samples produced without it. Addition of honeysuckle berries preparation significantly influenced the yogurts’ color, giving them deep purple color, and their antioxidant potential. During storage, contents of anthocyanin and iridoid compounds were decreasing, but antioxidant activity in the products remained stable.

Two Balkan Peninsula endemics, Nepeta rtanjensis and N. argolica subsp. argolica, both characterized by specialized metabolite profiles predominated by iridoids and phenolics, are differentiated according to the stereochemistry of major iridoid aglycone nepetalactone (NL). For the first time, the present study provides a comparative analysis of antimicrobial and immunomodulating activities of the two Nepeta species and their major iridoids isolated from natural sources—cis,trans-NL, trans,cis-NL, and 1,5,9-epideoxyloganic acid (1,5,9-eDLA), as well as of phenolic acid rosmarinic acid (RA). Methanol extracts and pure iridoids displayed excellent antimicrobial activity against eight strains of bacteria and seven strains of fungi. They were especially potent against food-borne pathogens such as L. monocytogenes, E. coli, S. aureus, Penicillium sp., and Aspergillus sp. Targeted iridoids were efficient agents in preventing biofilm formation of resistant P. aeruginosa strain, and they displayed additive antimicrobial interaction. Iridoids are, to a great extent, responsible for the prominent antimicrobial activities of the two Nepeta species, although are probably minor contributors to the moderate immunomodulatory effects. The analyzed iridoids and RA, individually or in mixtures, have the potential to be used in the pharmaceutical industry as potent antimicrobials, and in the food industry to increase the shelf life and safety of food products.

Picrorhiza kurroa is a medicinal herb rich in hepatoprotective iridoid glycosides , picroside-I (P-I) and picroside-II (P-II). The biosynthetic machinery of picrosides is poorly understood, therefore, ‘no-direction’ gene co-expression networks were used to extract linked/closed and separated interactions in terpenoid glycosides-specific sub-networks. Transcriptomes generated from different organs, varying for P-I and P-II contents such as shoots grown at 15 and 25 °C and nursery-grown shoots, stolons, and roots resulted in 47,726, 44,958, 40,117, 66,979, and 55,578 annotated transcripts, respectively. Occurrence of 2810 ± 136 nodes and 15,626 ± 696 edges in these networks indicated intense, co-expressed, closed loop interactions. Either deregulation/inhibition of abscisic acid (ABA) biosynthesis/signaling or constitutive degradation of ABA resulted in organ-specific accumulation of P-I and P-II. Biosynthesis, condensation and glucosylation of isoprene units may occur in shoots, roots or stolons; but addition of phenylpropanoid moiety and further modification/s of the iridoid backbone occurs mainly inside vacuoles in roots.

Phlomis bruguieri is a native plant in Iran, which deserves phytochemical study. The aim of this study was evaluation of its iridoid contents along with its antioxidant capacity. Aerial parts of the plant material were extracted with methanol and applied on repeated normal column chromatography using hexane: chloroform (70:30), chloroform: methanol (90:10), and methanol (100%). The fraction eluted with methanol (100%) containing polar glycosides was selected and medium pressure liquid chromatography (MPLC) on a RP-18 cartridge. Fraction elute by MeOH: water 30:70 was loaded on HPLC on RP-18 column for final purification. Structure elucidation was done using 1D and 2D NMR, and mass spectra. Antioxidant activity including total antioxidant capacity, DPPH and FRAP methods were designated to assess the in vitro antioxidant capacities. This study indicated the presence of lamiide as iridoid compound in the aerial parts of Phlomis bruguieri for the first time in this plant [350 mg/2 kg; 0.0175 % (w/w)]. Lamiide showed moderate antioxidant activity using TAC (EC50: 55 μg/mL; ascorbic acid EC50: 7.5 μg/mL), DPPH (EC50: 116.2 ± 3.51 μg/mL; ascorbic acid:34.7 ± 0.97 μg/mL), and FRAP (EC50:>200 μg/mL; quercetin: 7.5 ± 0.68 μg/mL) methods.

Green Cavendish banana peel and pulp flours were obtained by three drying methods: oven dryer at 70 °C; air fryer at 180 °C and domestic oven at 180 °C, being the latter two new possibilities. Bioactive constituents using paper spray ionization mass spectrometry (PS-MS), phenolic identification and quantification by ultra-performance liquid chromatography with UV-Visible detection (UPLC/UV-Vis) and antioxidant capacity were evaluated. Phenolic acids showed distinct thermal stability between the treatments. Gallic acid was the predominant compound, ranging from (29.56 to 1211.74 mg 100 g−1) and had higher concentration than that found in other bananas described in literature. Green Cavendish banana flour is an advantageous source of bioactive compounds and antioxidant capacity, especially its peel. 26 compounds were identified by PS-MS: phenolics,organic acids, sugars, amino acid, phytosterol, iridoid and coumarin derivatives. Green Cavendish banana flour has great functional potential, and the air fryer can be a promising alternative for drying.

Basic helix‐loop‐helix (bHLH) transcription factors (TFs) are key regulators of plant specialized metabolites, including terpenoid indole alkaloids (TIAs) in Catharanthus roseus. Two previously characterized subgroup‐IVa bHLH TFs, BIS1 (bHLH Iridoid Synthesis 1) and BIS2 regulate iridoid biosynthesis in the TIA pathway. We reanalyzed the recently updated C. roseus genome sequence and discovered that BIS1 and BIS2 are clustered on the same genomic scaffold with a previously uncharacterized bHLH gene, designated as BIS3. Only a few bHLH gene clusters have been studied to date. Comparative analysis of 49 genome sequences from different plant lineages revealed the presence of analogous bHLH clusters in core angiosperms, including the medicinal plants Calotropis gigantea (giant milkweed) and Gelsemium sempervirens (yellow jessamine), but not in the analyzed basal angiosperm and lower plants. Similar to the iridoid pathway genes, BIS3 is highly expressed in roots and induced by methyl jasmonate. BIS3 activates the promoters of iridoid branch genes, geraniol synthase (GES), geraniol 10‐hydroxylase (G10H), 8‐hydroxygeraniol oxidoreductase (8HGO), iridoid synthase (IS), 7‐deoxyloganetic acid glucosyl transferase (7‐DLGT), and 7‐deoxyloganic acid hydroxylase (7DLH), but not iridoid oxidase (IO). Transactivation of the promoters was abolished when BIS3 is converted to a dominant repressor by fusing with the ERF‐associated amphiphilic repression (EAR) sequence. In addition, BIS3 acts synergistically with BIS1 and BIS2 to activate the G10H promoter in tobacco cells. Mutation of the known bHLH TF binding motif, G‐box (CACGTG) in the G10H promoter significantly reduced but did not abolish the transactivation by BIS3. Promoter deletion analysis of G10H suggests that the sequences adjacent to the G‐box are also involved in the regulation by BIS3. Overexpression of BIS3 in C. roseus flower petals significantly upregulated the expression of iridoid biosynthetic genes and increased loganic acid accumulation. BIS2 expression was significantly induced by BIS3 although BIS3 did not directly activate the BIS2 promoter. Our results advance our understanding of the regulation of plant specialized metabolites by bHLH TF clusters.

For the first time, the cytotoxic and phytochemical investigation of the leaves of Stereospermum binhchauensis V.S. Dang, a new species discovered in Viet Nam were finalized and led to purify nine compounds, including one furancoumarin (1), one chromone (3), two triterpenoids (2, 4), two flavonoids (5, 8), two flavanoids (6, 7) and one iridoid (9) using various chromatography methods. Their structures were verified by HR-ESI-MS, NMR experiments and compared with previous literatures. For the first time, compounds (5–8) were realized from the genus Stereospermum, while compounds (1, 2, 3, 4 & 9) were designated from the species S. binhchauensis. Furthermore, the furancoumarin, chromone and flavanoid classes were notified for the first time from the genus Stereospermum.

Food industries produce a high amount of waste every year. These wastes represent a source of bioactive compounds to be used to produce cosmetic and nutraceutical products. In this study, the possibility to retrain food waste as a potential source of bioactive metabolites is evaluated. In particular, metabolite profiles of different parts (bulb, leaves, stems and little stems) of fennel waste were investigated by liquid chromatography coupled with mass spectrometry (LC-ESI/LTQ Orbitrap MS). To discriminate the different plant parts, a Multivariate Data Analysis approach was developed. Metabolomic analysis allowed the identification of different metabolites mainly belonging to hydroxycinnamic acid derivatives, flavonoid glycosides, flavonoid aglycons, phenolic acids, iridoid derivatives and lignans. The identification of compounds was based on retention times, accurate mass measurements, MS/MS data, exploration on specific metabolites database and comparison with data reported in the literature for F. vulgare. Moreover, the presence of different oxylipins was relieved, these metabolites for the first time were identified in fennel. Most of the metabolites identified in F. vulgare possess anti-inflammatory, antioxidant and/or immunomodulatory properties. Considering that polyphenols are described to possess antioxidant activity, spectrophotometric tests were performed to evaluate the antioxidant activity of each part of the fennel.

A new acylated iridoid, valejatadoid H (1), along with fourteen known compounds, were obtained from the n-BuOH extract of the roots and rhizomes of Valeriana jatamansi, and their structures were elucidated by various spectroscopic methods. Among them, compounds 8, 11 and 13 exhibited potent inhibition on NO production, with IC50 values of 4.21, 6.08 and 20.36 μM, respectively. In addition, compounds 14 and 15 showed anti-influenza virus activities, among which compound 14 exhibited significant effect with an IC50 value of 0.99 μM.

Microbial production of monoterpenes has attracted increasing attention in recent years. Up to date, there are only few reports on the biosynthesis of the monoterpene alcohol citronellol that is widely used as fragrant and pharmaceutical intermediates. Here, we engineered Saccharomyces cerevisiae by employing a “push-pull-restrain” strategy to improve citronellol production based on the reduction of geraniol. Starting from a engineered geraniol-producing strain, different reductases were investigated and the best performing iridoid synthase from Catharanthus roseus (CrIS) resulted in 285.89 mg/L enantiomerically pure S-citronellol in shake flasks. Geranyl diphosphate (GPP), the most important precursor for monoterpenes, was enhanced by replacing the wild farnesyl diphosphate synthase (Erg20) with the mutant Erg20F96W, increasing the citronellol titer to 406.01 mg/L without negative influence on cell growth. Moreover, we employed synthetic protein scaffolds and protein fusion to colocalize four sequential enzymes to achieve better substrate channeling along with the deletion of an intermediate degradation pathway gene ATF1, which elevated the citronellol titer to 972.02 mg/L with the proportion of 97.8% of total monoterpenes in YPD medium. Finally, the engineered strain with complemented auxotrophic markers produced 8.30 g/L of citronellol by fed-batch fermentation, which was the highest citronellol titer reported to date. The multi-level engineering strategies developed here demonstrate the potential of monoterpenes overproduction in yeast, which can serve as a generally applicable platform for overproduction of other monoterpenes.

Medicinal plants play an important role in traditional medicine and new drug development, but the increased use of wild plant-based traditional medicine presents a potential biodiversity conservation threat. A better understanding of environmental factors on bioactive compounds in medicinal plants is necessary to ensure the suitability of cultivation location, the sustainability of market supply, and the future conservation of the wild populations. Gentiana rigescens Franch. ex Hemsl. has been used as a medicinal plant in China for hundreds of years due to containing iridoid glycoside compounds, but we knew little about how these compounds respond to environmental changes. We therefore investigated the accumulation and distribution of four iridoid glycosides (loganic acid, sweroside, swertiamarin, and gentiopicroside) in G. rigescens individuals from 28 wild populations in the elevation range of 1260–2978 m in southwest China. We also analyzed the impact of environmental factors (geography, climate, and soil) on the content of gentiopicroside (the dominant compound) in this species. We found significant variations of the contents of the four iridoid glycosides in each part of G. rigescens among populations (p

The root of Phlomis umbrosa has traditionally been used as a medicine in South Asian nations to treat colds and bone fractures, to staunch bleeding, and as an anti-inflammatory, and such use continues today. We identified 10 genes that are involved in terpenoid biosynthesis, while using the Illumina/Solexa HiSeq2000 platform. We investigated the transcript levels of the 10 genes using quantitative real-time PCR and quantified the level of terpenoid accumulation in different organs of P. umbrosa while using high-performance liquid chromatography. The transcript levels of PuHDR and PuHMGR1 were the highest among the studied genes. Sesamoside, an iridoid glycoside, appeared in higher quantity than shanzhiside methylester, umbroside (8-O-acetyl shanzhiside methyl ester), and acteoside. We speculate that PuHDR and PuHMGR1 may contribute to terpenoid biosynthesis in P. umbrosa. This study highlights the molecular mechanisms that underlie iridoid glycoside biosynthesis in P. umbrosa.

Monoterpenoid alkaloids are well known for their broad and excellent biological activities, but their extremely low content and complex chemical structure limit their practical application. This study used the biosynthetic precursor genipin as a basic material to conduct a biomimetic synthesis of iridoid alkaloids. The structures of the iridoid alkaloids were characterized by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry, and their fungicidal and insecticidal activities were evaluated. Bioassay results indicated that iridoid alkaloids possess good to excellent activities against phytopathogenic fungi, diamondback moth, bean aphid, and spider mite. Compound 3s had the most promising activity against three important phytopathogenic fungi Fusarium graminearum (LC50 value of 34.5 μg/mL with a 95% confidence interval of 33.4-35.5 μg/mL), Rhizoctonia solani (18 μg/mL, 15.7-20.8 μg/mL), and Botrytis cinerea (26 μg/mL, 22.4-30.4 μg/mL), thereby emerging as a potential new fungicidal lead. The structure-activity relationship research has shown that the electrical property and steric hindrance sizes of iridoid alkaloids apparently influence fungicidal activity. Moreover, compound 3n exhibited good insecticidal activity against diamondback moth with an LC50 (35.6 μg/mL, 95% confidence interval 19.0-66.6 μg/mL) comparable to that of the commercial insecticide rotenone (35.4 μg/mL, 95% confidence interval 22.2-56.4 μg/mL). This outcome indicates that this compound deserves further study as a potential lead for development of new insecticides.

A variety of drugs are widely used to treat fungal infections. Mostly they are products of chemical synthesis, but recently, due to the increased resistance of fungi to many synthetic drugs, the relevance of the use of herbal remedies in the complex treatment of both skin infections and deep mycoses has been increasing. The aim of our research was to study the chemical composition of the lyophilic extracts of Plantago media and Plantago altissima of the flora of Ukraine by HPLC and GLC-MS methods and also mycostatic activity of ethanol and lyophilic extracts of the studied plants. As a result of the research, aucubin iridoid was detected in the lyophilic extracts of both species. There were also detected 15 polyphenolic compounds among which prevails acteoside, plantamayoside, ferulic and chlorogenic acid. Alcohol and lyophilic extracts of P. media and P. altissima showed mycostatic activity to all studied strains of yeast, dermatophytic fungi and aspergillus. The mycostatic effect of alcoholic extracts of P. media and P. altissima was more evident in comparison with the mycostatic effect of lyophilic extracts. The most evident antifungal effect was presented by alcoholic extract of P. media in relation to the clinical strain of Aspergillus oryzae (18.0±1.0 mm), and alcoholic extract of P. altissima to the clinical strain of Malassezia sp. (18.0±0.5 mm). The data obtained indicate a wide range of mycostatic effects of Plantago media and Plantago altissima extracts and the prospectivity of these objects for practical use in medicine.

Seven undescribed (valejatadoids A−G) and 26 known iridoids were obtained from the roots and rhizomes of Valeriana jatamansi. Their structures were determined based on extensive spectroscopic data, especially 1D and 2D NMR, along with HRESIMS. Valejatadoid B is a monoene-type iridoid with a unique double bond between C-4 and C-5. Valejatadoids D−G, jatamanin U, jatamanin O, jatamanvaltrate E, valeriotetrate C, IVHD-valtrate, 10-isovaleroxy-valtrathydrin, jatamanvaltrate Q, valeriandoid F, jatamanvaltrate K, jatamanvaltrate W and isovaltrate were more potent than the positive control when evaluated for inhibition of NO production. Among them, valeriandoid F and jatamanvaltrate K exhibited the most significant inhibitory effects with IC50 values of 0.88 and 0.62 μM, respectively. In addition, valeriandoid F selectively inhibited the proliferation of human glioma stem cell lines, GSC-3# and GSC-18#, with IC50 values of 7.16 and 5.75 μM, respectively.

Ethnopharmacological relevance Chilean population relies on medicinal plants for treating a wide range of illnesses, especially those of the gastrointestinal system. Junellia spathulata (Gillies & Hook.) Moldenke var. spathulata (Verbenaceae), called as “verbena-azul-de-cordilleira”, is a medicinal plant native to Argentina and Chile traditionally used for treating digestive disorders. Although the species of the genus are important as therapeutic resources for the Andean population, the plants are very scarcely studied. Aims of the study The purpose of the present study was to find out the main constituents and investigate the protective effect of J. spathulata against oxidative stress induced by the potent oxidant 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH) in human hepatoblastoma cells. Materials and methods The crude methanol extract of J. spathulata and an iridoid obtained by chromatographic processes were tested to access the hepatoprotective effect and cytotoxicity in HepG2 cell. In addition, the reducing power of the samples and their ability to scavenge free radicals were evaluated using FRAP and ORAC assay systems. Results The iridoid asperuloside, the main compound of the crude methanol extract of J. spathulata, was isolated and identified by means of NMR analysis. The crude methanol extract of J. spathulata and asperuloside protected HepG2 cells against oxidative damage triggered by AAPH-derived free radicals. This effect can be credited to the ability of the extract and asperuloside to protect the liver cells from chemical-induced injury, which might be correlated to their free radical scavenging potential. Conclusions This study experimentally evidenced the ethnopharmacological usefulness of J. spathulata as a treatment of digestive disorders. Our result could stimulate further investigations of hepatoprotective agents in other Chilean Junellia species.

Introduction Verbascum betonicifolium (V. betonicifolium) is a plant used in traditional medicine for several ailments. The objective of this study was to determine the antioxidant activity and acetylcholinesterase inhibitory activity of the aqueous extract together with the metabolites responsible for these activities. This paper presents the first phytochemical characterization and bioactivities of aqueous extracts from aerial parts. Methods The compounds present in the aerial part aqueous extract were identified by high performance liquid chromatography, coupled to a diode-array detector (HPLC-DAD) and by high-resolution mass spectrometry (HRMS), using LC–MS/MS analyses. Antioxidant activity was measured as the capacity to scavenge the free radical DPPH and the AChE activity was determined using the Ellman test. The cytotoxicity was determined used HepG2 cell lines. Results Several types of metabolites were found, primary metabolites (malic, citric and gluconic acids), phenolic compounds (verbascoside, luteolin), terpenoids (iridoid glycoside, unedide), among others. The total phenol content of 28 μg of gallic acid equivalents/mg of extract was determined. The aqueous extract antioxidant activity had and EC50 of 70 μg/mL and the AChE inhibitory activity an IC50 of 750 μg/mL. No cytotoxicity towards HepG2 cells was detected, even using a concentration of 1 mg/mL. Conclusions The phenolic compounds present in the extract may be the main contributors to the bioactivities of V. betonicifolium. These results show for the first time the richness of phytochemicals and the strong bioactivities of V. betonicifolium and that the aqueous extract could be used as new natural sources of bioactive molecules.

Traditional medicine is still widely practiced in Iraqi Kurdistan, especially by people living in villages on mountainous regions, medicinal plants are also sold in the markets of the large towns, such as at Erbil, the capital of the Kurdistan Autonomous Region. About a dozen of Verbascum species (Scrophulariaceae) are commonly employed in the Kurdish traditional medicine, especially for treating burns and other skin diseases. However, the isolation of bioactive secondary metabolites from these plants has not been the subject of intense scientific investigations in Iraq. Therefore, the information reported in the literature about the species growing in Kurdistan has been summarized in the first part of this paper, although investigations have been performed on vegetable samples collected in neighbouring countries, such as Turkey and Iran. In the second part of the work, we have investigated, for the first time, the contents of a methanol and a hydromethanol extract of V. calvum flowers. The extracts exhibited weak antimicrobial activities, whereas the methanol extract showed significant antiproliferative effects against an A549 lung cancer cell line. Moreover, both extracts exhibited a significant dose-dependent free radical scavenging action against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, comparable to that of ascorbic acid. In the subsequent phytochemical study, a high phenolic content was determined in both extracts by the Folin&ndash, Ciocalteu assay and medium-pressure liquid chromatographic (MPLC) separation led to the isolation of iridoid glucosides ajugol and aucubin from the methanol extract. In conclusion, the high anti-inflammatory effects of aucubin and the remarkable antioxidant (antiradical) properties of the extracts give scientific support to the traditional use of V. calvum flowers for the preparation in Kurdistan of remedies to cure skin burns and inflammations.

The purpose of this study was to develop a method for simultaneous analysis of aucubin, catalpol, and geniposide, which are representative iridoid glycoside constituents of Rehmannia glutinosa, in rat plasma, urine, and feces using hydrophilic interaction ultra high-performance liquid chromatography with tandem mass spectrometry. The three components were separated using 10 mmol/L aqueous ammonium formate containing 0.01% (v/v) formic acid and acetonitrile as a mobile phase by gradient elution at a flow rate of 0.2 mL/min, equipped with a Kinetex® HILIC column (50 × 2.1 mm, 2.6 μm). Quantitation of this analysis was performed on a triple quadrupole mass spectrometer employing electrospray ionization and operated in multiple reaction monitoring mode. The chromatograms showed high resolution, sensitivity, and selectivity with no interference with plasma constituents. In all three iridoid glycosides, both the intra- and interbatch precisions (coefficient of variation %) were less than 4.81%. The accuracy was 96.56-103.55% for aucubin, 95.23-106.21% for catalpol, and 94.50-104.16% for geniposide. The developed analytical method satisfied the criteria of international guidance and was successfully applied to pharmacokinetic studies including oral bioavailability of aucubin, catalpol, and geniposide, and their urinary and fecal excretion ratios after oral or intravenous administration to rats. The new method was also applied to measure plasma protein binding ratios in vitro.

Gentiana rigescens Franch. ex Hemsl. is an important medicinal plant in China and the over exploitation of wild resources has affected its quality and clinical efficacy. The accumulation of plant secondary metabolites is not only determined by their genetic characteristics but also influenced by environmental factors. At present, many studies on evaluating the environmental conditions of its planting area are still in the qualitative stage. Therefore, it is necessary to establish a systematic evaluation method to deeply analyze the impact of environmental factors on the quality of medicinal materials and quickly verify the geographical origin. In this study, the contents of five iridoids (loganic acid, swertiamarin, sweroside, gentiopicroside and 6'-O-β-D-glucopyranosylgentiopicroside) of G. rigescens from 45 different origins (including 441 individuals) of Yunnan Province in China were analyzed by high performance liquid chromatography. Analytical procedures of one-way analysis of variance, correlation analysis, principal components analysis, and hierarchical cluster analysis were employed to interpret the correlation of iridoid content and environmental factors. Fourier transform infrared spectroscopy (FT-IR) combined with two multivariate analysis methods (partial least squares discriminant analysis; support vector machines, SVM) was used to discriminate four major producing areas (158 individuals). The combination of SVM with grid search algorithm achieved an accuracy of 100% in the test set. One-way analysis of variance showed that the contents of five iridoids in root tissues of G. rigescens varied significantly among different origins, which was also verified by the chemometrics analysis results of hierarchical cluster analysis. The results of correlation analysis indicated that the high value of altitude and precipitation were unfavorable for the accumulation of these five iridoids. A correlation between increase of temperature and iridoid accumulation was observed. This study provided a certain theoretical basis for the resource protection and development of G. rigescens based on the correlation analysis between the ecological environment factors and quality.

The conditions to efficiently and reproducibly extract geniposide and genipin in Gardenia fruit powders were established using Taguchi experimental design approaches to improve extraction recovery. Geniposide, the major iridoid glycoside component of Gardenia fruits, which has been recognized to have choleretic effects, is transformed to Genipin in animals. In this study, the extraction conditions of geniposide and genipin such as solvent types, solvent acidities and boiling times were investigated under the guidance of experimental designs to obtain the highest content in extracts determined with liquid chromatography-mass spectrometry (LC-MS) methods. Herbal powders ground from Gardenia fruits, Gardenia jasminoides Ellis and Gardenia jasminoides Ellis var. grandiflora Nakai, were used. This paper has successfully demonstrated the use of Taguchi orthogonal arrays to obtain proper extraction conditions of geniposide and genipin in the above fruits. These design methods are capable of obtaining the optimum extraction conditions in only nine trials in which three factors, namely solvent type, boiling time and solvent acidity are investigated. The results show that solvent acidity is the influencing factor in achieving adequate contents and the other factors only have minor influences. The highest content obtained is similar to the reported data. In addition, using Taguchi orthogonal arrays within four experimental trials has identified that the extraction of ground fine powders results in more reproducible recovery than that of coarse ones.

Fourteen undescribed diterpenoids caryopterisoids D - Q, three undescribed iridoid glucoside derivatives caryopterisides F - H, and 8 known diterpenoids were isolated from the 95% aqueous ethanolic extract of Caryopteris glutinosa. Their structures were elucidated on the basis of spectroscopic data analysis and chemical derivation studies. The structure and absolute configuration of caryopterisoid D were confirmed by X-ray crystallographic analysis. Caryopterisoids K and R, royleanone, 6α-hydroxydemethylcryptojaponol, and teuvincenone E were shown to reduce the biosynthesis of estrogen E2 with IC50 values from 0.25 to 3.06 μM in cell-based estrogen biosynthesis assays system.

The trunk bark of Tabebuia caraiba Bignoniaceae was found to contain four novel iridoids, 6-O-E-p-coumaroyljioglutin D (2), 6-O-E-p-coumaroyl-3-demethyl-3-O-ethyljioglutin D (3), 6-O-E-p-coumaroyl-1-demethyl-1-O-ethyljioglutin D (4), 7-O-E-p-coumaroyljiofuranaldehyde (5), three known iridoids, including one iridoid glucoside, jioglutin D (1), rehmaglutin D (6), 6-O-E-p-coumaroylcatalpol (7). From the flowers were obtained six triterpenes, betulinic acid (8), olean-12-en-3-one (9), β-amyrin (10), oleanolic acid (11), ursolic acid (12), 3-O-E-p-coumaroylursolic acid (13), 2α-hydroxyursolic acid (14), 6β,19α-dihydroxyursolic acid (15), and one phenylethanoid, tyrosol (16), in addition to β-sitosterol, β-sitosterol-3-O-β-D-glucopyranoside and β-sitosterol-3-O-β-D-(6´-O-acyl)-glucopyranoside and E-p-coumaric acid. The structures of the isolated compounds were established on the basis of 1D and 2D NMR spectroscopic techniques. The chemical profile of the trunk bark of the plant was determined by HPLC/DAD/HRESIMS and did not present a good correlation with the phytochemical study. It did not detect most of the isolated substances and allowed to propose the presence of some non-isolated compounds.

Ethnopharmacological significance Gmelina arborea Roxb.ex Smith, a fast-growing deciduous tree belongs to the family Lamiaceae, and is an important plantation species in many tropical areas around the world. The species is naturally distributed in semi-deciduous forests in tropical/subtropical regions of South East Asia. The tree is also an important medicinal plant in the Indian Systems of Medicine. The whole plant is used in medicine. It is astringent, bitter, digestive, cardiotonic, diuretic, laxative and pulmonary and nervine tonic. It improves digestion, memory, helps overcome giddiness and is useful in burning sensation, fever, thirst, emaciation, heart diseases, nervous disorders and piles. The roots are acrid, bitter-sweet in taste, stomachic, tonic, laxative, galactagogue and antihelmintic. The flowers are sweet, refrigerant, bitter, astringent and acrid, and are used in treating leprosy and skin diseases. The fruits are acrid, sour, sweet, refrigerant, bitter, astringent, aphrodisiac, trichogenous, alterant and tonic. Fruits are edible and also used for promoting hair growth and in treating anaemia, leprosy, ulcers, constipation, leucorrhoea and colitis. The leaves are a good fodder also. The major bioactive compounds extracted from different parts of G. arborea are arboreal, verbascoside, tyrosol, iridoids, phenylpropanoid glycoside, premnazole, martynoside, iridoid glycosides, balanophonin, gmelinol, isoarboreol apigenin, umbelliferone etc. Aim of the review This review provides an insight into the medicinal aspects of G. arborea. It provides the latest information on phytochemistry, pharmacological activities and traditional uses of G.arborea. Materials and methods Information on G. arborea was gathered from various sources like textbooks, literature, databases such as PubMed, Science Direct, Wiley, Springer, Taylor and Francis, Scopus, Inflibnet, Sci-Finder and Google Scholar. Results Sixty-nine phytochemicals which include lignans, acylated iridoid glycosides, acylated rhamnopyranoses, flavonoids, flavones, flavone glycosides have been isolated. Many of them have been characterized for their pharmacological activity. Several researchers have identified bioactive phytochemicals like luteolin, iridoid alkaloids from the leaves, hentriacontanol and lignans such as arboreol, isoarboreol, arborone, gmelanone, gummadiol from the heartwood, flavon glycosides in roots. The extracts are reported to have wound-healing and antidiarrheal properties. Various studies demonstrated that G.arborea and its constituents possess several pharmacological activities like anti-oxidant, anti-diabetic, anti-inflammatory, antiulcer, analgesic, anti-nociceptive, anticancer and wound healing activities. Conclusion G. arborea is a valuable medicinal plant used traditionally in the Indian Systems of Medicine (ISM - Ayurveda and Unani) to treat a wide variety of ailments. These phytochemicals are highly bioactive and exhibit various pharmacological activities. However, pharmacological activities of many compounds which have been identified, are yet to be understood.

A series of iridoid glycosides were isolated from the leaves of Lasianthus verticillatus (Lour.) Merr., belonging to family Rubiaceae. A new iridoid glycoside, lasianoside F (1), and three new bis-iridoid glycosides, lasianosides G&ndash, I (2&ndash, 4), together with four known compounds (5&ndash, 8) were isolated. The structures were established by spectroscopic methods, including 1D and 2D NMR experiments (1H, 13C, DEPT, COSY, HSQC, HMBC, and NOESY) in combination with HR-ESI-MS and CD spectra.

Background:: Catalpol, an iridoid glycoside, is one of the richest bioactive components present in Rehmannia glutinosa. More and more metabolites of drugs have exhibited various pharmacological effects, thus providing guidance for clinical application. However, few researches have paid attention to the metabolism of catalpol. Objective:: This study aimed to establish a rapid and effective method to identify catalpol metabolites and evaluate the biotransformation pathways of catalpol in rats. Methods:: In this study, catalpol metabolites in rat urine, plasma and faeces were analyzed by UHPLC-Q-Exactive MS for the characterization of the metabolism of catalpol. Based on high-resolution extracted ion chromatograms (HREICs) and parallel reaction monitoring mode (PRM), metabolites of catalpol were identified by comparing the diagnostic product ions (DPIs), chromatographic retention times, neutral loss fragments (NLFs) and accurate mass measurement with those of catalpol reference standard. Results: A total of 29 catalpol metabolites were detected and identified in both negative and positive ion modes. Nine metabolic reactions, including deglycosylation, hydroxylation, dihydroxylation, hydrogenation, dehydrogenation, oxidation of methylene to ketone, glucuronidation, glycine conjugation and cysteine conjugation, were proposed. Conclusion:: A rapid and effective method based on UHPLC-Q-Exactive MS was developed to mine the metabolism information of catalpol. Results of metabolites and biotransformation pathways of catalpol suggested that when orally administrated, catalpol was firstly metabolized into catalpol aglycone, after which phase I and phase II reactions occurred. However, hydrophilic chromatography-mass spectrometry is still needed to further find the polar metabolites of catalpol.

The authors are grateful to the Cyprus University of Technology Open Access Author Fund. Sideritis species are recognized as important medicinal plants and their commercial demand is continuously on the rise both in the European and in the global market. Consequently, the cultivation of Sideritis species has been occurred to successfully meet the need for mass production of high-quality plant material. The present study was undertaken in order to investigate the chemical composition of cultivated S. cypria. Infusions of flowers and leaves were prepared separately, according to the European Medicine Agency (EMA) monograph. The infusion of the flowers revealed the presence of four flavones, isoscutellarein-7-O-[6'″-O-acetyl-β-D-allopyranosyl-(1→2)-β-D-glucopyranoside, its 4'-O-methyl-derivative, 4'-O-methyl-hypolaetin-7-O-[6'″-O-acetyl-β-D-allopyranosyl-(1→2)-β-D-glucopyranoside, and isoscutellarein-7-O-[6'″-O-acetyl-β-D-allopyranosyl-(1→2)]-6″-O-acetyl-β-D-glucopyranoside; four phenylethanoid glucosides, acteoside, leucosceptoside A, lamalboside, and leonoside A; one iridoid, melittoside, and one phenolic acid, chlorogenic acid, while the infusion of the leaves of the same population afforded the same first two flavones; five phenylethanoid glucosides, acteoside, leucosceptoside A, lavandulifolioside, leonoside A, and lamalboside; melittoside and chlorogenic acid. The structural elucidation of the isolated compounds was undertaken by high-field NMR spectroscopy. Moreover, the essential oils of the flowers and leaves were studied by GC-MS, separately. In addition, the mineral, bioactive compounds, protein and carbohydrate contents were evaluated for both plant materials.