Antinociceptive and anti-inflammatory kaempferol glycosides from Sedum dendroideum

Aim of the study

To identify the compounds responsible for the antinociceptive and anti-inflammatory effects previously described for Sedum dendroideum, through bioassay-guided fractionation procedures.

Materials and methods

Antinociceptive activity was evaluated through mouse acetic acid-induced writhing model. The anti-inflammatory activity was assessed through croton oil-induced mouse ear oedema and carrageenan-induced peritonitis.

Results

The Sedum dendroideum juice afforded seven known flavonoids identified with basis on NMR data. The oral administration of the major kaempferol glycosides kaempferitrin [1] (17.29 μmol/kg), kaempferol 3-O-β-glucopyranoside-7-O-α-rhamnopyranoside [2] (16.82 μmol/kg), kaempferol 3-O-neohesperidoside-7-O-α-rhamnopyranoside [3] (13.50 μmol/kg) or α-rhamnoisorobin [5] (23.13 μmol/kg) inhibited by 47.3%, 25.7%, 60.2% and 58.0%, respectively, the acetic acid-induced nociception (indomethacin: 27.95 μmol/kg, p.o.; 68.9%). Flavonoids 1, 2, 3 or 5, at the same doses, reduced by 39.5%, 46.5%, 35.6% and 33.3%, respectively, the croton oil-induced oedema (dexamethasone: 5.09 μmol/kg, s.c.; 83.7%) and impaired leukocyte migration by 42.9%, 46.3%, 50.4% and 49.6%, respectively (dexamethasone: 5.09 μmol/kg, s.c.; 66.1%).

Conclusions

Our findings show that the major kaempferol glycosides may account for the renowned medicinal use of Sedum dendroideum against pain and inflammatory troubles.     

The constituents of Cibotium barometz and their permeability in the human Caco-2 monolayer cell model

Ethnopharmacological relevance

Cibotium barometz (L.) J. Sm. (Dicksoniaceae) has been traditionally used as anti-inflammatory and anodyne.

Aim of the study

To investigate the constituents in the rhizomes of Cibotium barometz, and evaluate their permeability in the human Caco-2 model.

Materials and methods

The rhizomes extracts of Cibotium barometz were isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods. The permeability of the main constituents was evaluated using human Caco-2 cell monolayer as a model system.

Results

Three unusual sesquiterpenes having 1-indanone nucleus (1, 3 and 4) and an unusual orthoester spiropyranosyl derivative of protocatechuic acid (2) were isolated from the rhizomes of Cibotium barometz. Among these, the bilateral permeation of 1, 3 and 4 in Caco-2 model was examined. The apparent permeability coefficients (P_app) of 1 was identical with those of propranolol, which is often used as reference standard of high permeability. The P_app values of 3 and 4 were in agreement with those of atenolol, which is often used as reference standard of poor permeability. The permeation rates of 1, 3 and 4 increased linearly as a function of time up to 180 min and with the concentration within the test range of 25–200 μM.

Conclusions

This is the first report on the presence of compounds 2 and 3 in this plant and 4 was a new compound. Compound 1 is assigned for a well-absorbed, and 2 and 3 are assigned for the poorly absorbed compounds in human intestine. A passive diffusion mechanism for transport of 1, 3 and 4 in Caco-2 model was proposed. The results provided some useful information for predicting the oral bioavailability of 1, 3 and 4.     

Bioactivity-guided isolation of polyacetylenes with inhibitory activity against NO production in LPS-activated RAW264.7 macrophages from the rhizomes of Atractylodes macrocephala

Ethnopharmacological relevance

The rhizome of Atractylodes macrocephala (Compositae) is one of the most well-known traditional Chinese medicine in China, Japan and Korea, which has a long history of use for the treatment of splenic asthenia, edema, anorexia, and excessive perspiration, etc. As active compounds of anti-inflammatory activity of this medicinal plant have not been fully elucidated, the aim of this study was to isolate and identify the active constituents inhibiting nitric oxide (NO) production from the rhizomes of A. macrocephala.

Materials and methods

Inhibitory activity against NO production in lipopolysaccharide-activated RAW264.7 macrophages was evaluated by Griess reaction. Fifteen polyacetylenes were isolated from the active ethyl acetate extract using activity-guided screening. The structures of all compounds were elucidated by spectroscopic methods and comparison with published data. The compounds were further tested for their inhibitory activity against NO production.

Results

Seven new polyacetylenes, named atractylodemaynes A–G (1–7), along with eight known ones (8–15) were isolated. Compound 14 was isolated for the first time from the rhizomes of A. macrocephala. The study showed that the tested compounds exhibited inhibitory activity against NO production in a dose-dependent manner. Among them, compounds 10, 11 and 12 had relatively stronger inhibitory effect with IC₅₀ values of 28, 23 and 19 μM, respectively.

Conclusion

The results demonstrated that the polyacetylenes might greatly contribute to the anti-inflammatory activity of the rhizomes of A. macrocephala.     

Antimicrobial activities of methanol extract and compounds from stem bark of Vismia rubescens

Ethnopharmacological relevance

The plant, Vismia rubescens (Guttiferae) is popularly used in Cameroon and in several parts of Africa as febrifugal and for the treatment of various microbial infections (skin diseases, diarrhoea and venereal diseases).

Aim of the study

This study was mapped out to evaluate the antimicrobial activities of the methanol extract and compounds from the stem bark of Vismia rubescens.

Materials and methods

Structures of the compounds obtained after column chromatography of the methanol-soluble fraction were determined by spectroscopy and in comparison with published data. The broth micro-dilution method was used to evaluate the antimicrobial activities against three bacteria species (Salmonella typhi, Stahylococcus aureus and Pseudomonas aeruginosa) and four yeast species (Candida albicans, Candida tropicalis, Candida parapsilosis and Cryptococcus neoformans).

Results

Chemical analysis of the methanol extract from the stem bark of Vismia rubescens yielded five known compounds 1,4,8-trihydroxyxanthone (1), 1,7-dihydroxyxanthone (2), physcion (3), friedelin (4) and friedelanol (5). The crude extract and compounds 1, 2 and 3 exhibited both antibacterial and antifungal activities that varied between the microbial species (MIC = 3.12–1000 μg/ml). Compounds 2 and 3 were the most active (MIC = 3.12–100 μg/ml) while Stahylococcus aureus and Pseudomonas aeruginosa were sensitive to all the tested compounds. The antimicrobial activity of this plant as well as that of compounds 1 and 2 is being reported here for the first time.

Conclusion

These results provide promising baseline information for the potential use of this plant as well as some of the isolated compounds in the treatment of skin diseases and diarrhoea.     

In vitro relaxant and spasmolytic effects of constituents from Viburnum prunifolium and HPLC quantification of the bioactive isolated iridoids

Ethnopharmacological relevance

Viburnum prunifolium is a North America shrub used in ethnomedicine because of its spasmolytic, sedative, and anti-asthmatic properties.

Aim of the study

Contrasting results were reported in past literature about the active principles of this plant. Our aim was to clarify this matter by evaluating the relaxant and spasmolytic activities of the main constituents obtained from the drug.

Materials and methods

The pharmacological assays were carried out on rabbit jejunum spontaneous contractions and on guinea-pig carbachol-precontracted trachea.

Results

Cumulative concentration (1–100 μg/ml) of Viburnum prunifolium methanolic extract (MeOH extract), its purified fractions soluble in ethylacetate (EtOAc fraction) and in n-butanol (BuOH fraction), and the iridoid glucosides (2 × 10⁻⁵ to 4 × 10⁻⁴ M): 2′-O-acetyldihydropenstemide (1), 2′-O-trans-p-coumaroyldihydropenstemide (2), 2′-O-acetylpatrinoside (3), and patrinoside (4), isolated from EtOAc fraction (1 and 2) and BuOH fraction (3 and 4), induced both relaxant effect of rabbit jejunum spontaneous contractions and spasmolytic effect on guinea-pig carbachol (5.5 × 10⁻⁷ M)-precontracted trachea. Propranolol (10⁻⁶ M) antagonised all Viburnum prunifolium tested components relaxant and spasmolytic effects. At non-relaxing concentrations (0.5 μg/ml), MeOH extract and its fractions induced a potentiating effect of isoprenaline cumulative concentrations also in both isolated tissues.

Conclusion

In both tissues, the order of potency was EtOAc fraction > BuOH fraction > MeOH extract and 1 > 2 > 3 > 4 suggesting that the major iridoids of EtOAc fraction may be considered among the most active compounds.HPLC analysis of the bioactive iridoids indicates that 1 and 2 are present for 7.38% and 14.90% in EtOAc fraction, and 3 and 4 for 18.47% and 8.86% in BuOH fraction. By comparing the values of EC₅₀ of the fractions and compounds isolated from them, we may assume that the iridoids play a significant role in the biological activity of the corresponding fractions.     

Anti-inflammatory and immunosuppressive effect of flavones isolated from Artemisia vestita

Aim of the study

Artemisia vestita is a common traditional Tibetan medicinal plant which has been used widely in China for treating various inflammatory diseases. Since little is known about its active components, the purpose of this study was to isolate and identify the immunosuppressive compounds from Artemisia vestita.

Materials and methods

A bioassay-guided isolation was performed with picryl chloride-induced contact hypersensitivity in mice. MTT assay and Flow cytometric analysis were used for determining Con A-induced lymphocyte proliferation and CD25 expression in T cells, respectively.

Results

The ethanol extract of the Artemisia vestita was found to possess significant inhibitory activity against the picryl chloride-induced contact hypersensitivity in mice. Then 4 fractions were isolated by macroporous adsorption resin and one of these fractions (AV3), which showed the highest activity in in vivo test, was further subjected to column chromatography. Nine known flavones were isolated and identified as pectolinarigenin (1), jaceosidin (2), cirsilineol (3), cirsimaritin (4), hispidulin (5), quercetin (6), 6-methoxytricin (7), acacetin (8), and apigenin (9). The structures of the 9 flavones were elucidated by spectral techniques. All the compounds were evaluated for their inhibitory activity on the proliferation and activation of T cells in vitro. Among the 9 flavones, cirsilineol (3), 6-methoxytricin (7) and apigenin (9) significantly inhibited T cell proliferation and activation in the bioassays.

Conclusion

The result suggests that cirsilineol, 6-methoxytricin and apigenin are the major active components in Artemisia vestita.     

Bioactive styryllactones and alkaloid from flowers of Goniothalamus laoticus

Ethnopharmacological relevance

Goniothalamus laoticus (Annonaceae) is being used traditionally as a tonic and a febrifuge by the local people in the northeastern part of Thailand.

Aim of study

To investigate the Thai medicinal plant, Goniothalamus laoticus, for antiplasmodial, antimycobacterial and cytotoxicity activities.

Materials and methods

The flowers extracts of Goniothalamus laoticus were isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods. The antiplasmodial, antimycobacterial and cytotoxicity evaluation of styryllactone derivatives and alkaloid were also performed.

Results

Ten compounds, cinnamic acid (1); dihydrochrysine (2); β-sitosterol (3); six styryllactones, (+)-3-acetylaltholactone (4), goniotriol (5), (+)-altholactone (6), (+)-goniofufurone (7), 9-deoxygoniopypyrone (8), howiinin A (9); and an aporphine alkaloid; (−)-nordicentrine (10) were isolated from flowers of Goniothalamus laoticus. Among these, compounds 1, 3–5, 8–10 are first isolated from the Goniothalamus laoticus. Besides, compound 10 is the first report from the Goniothalamus genus. The isolated compounds were evaluated in antiplasmodial, antimycobacterial and anticancer cell lines tests. Compounds 4–6 and 10 exhibited antiplasmodial activity against Plasmodium falciparum (IC₅₀ 2.6, 7.9, 2.6 and 0.3 μg/mL, respectively), while 5, 6, 9 and 10 showed antimycobacterial activity against Mycobacterium tuberculosis (MIC 100, 6.25, 6.25 and 12.5 μg/mL, respectively). In addition, compounds 4–10 showed cytotoxicity against cancer cells, KB, BC1, NCI-H187, and MCF-7 with IC₅₀ ranging from 0.4 to 22.7 μg/mL.

Conclusion

This finding showed that the styryllactone derivatives and alkaloid isolated from the flowers of Goniothalamus laoticus exhibited antiplasmodial activity against Plasmodium falciparum, antimycobacterail against Mycobacterium tuberculosis and cytotoxicity against four cancer cell lines.     

Antitubercular activity of Arctium lappa and Tussilago farfara extracts and constituents

Ethnopharmacological relevance

Arctium lappa and Tussilago farfara (Asteraceae) are two plant species used traditionally as antitubercular remedies. The aim of this study was (i) to screen Arctium lappa and Tussilago farfara extracts for activity against Mycobacterium tuberculosis and (ii) to isolate and identify the compound(s) responsible for this reputed anti-TB effect.

Materials and methods

The activity of extracts and isolated compounds was determined against Mycobacterium tuberculosis H₃₇R_v using a high throughput spot culture growth inhibition (HT-SPOTi) assay.

Results

The n-hexane extracts of both plants, the ethyl acetate extract of Tussilago farfara and the dichloromethane phase derived from the methanol extract of Arctium lappa displayed antitubercular activity (MIC 62.5 μg/mL). Further chemical investigation of Arctium lappa led to the isolation of n-nonacosane (1), taraxasterol acetate (2), taraxasterol (3), a (1:1) mixture of β sitosterol/stigmasterol (4), isololiolide (5), melitensin (6), trans-caffeic acid (7), kaempferol (8), quercetin (9), kaempferol-3-O-glucoside (10). Compounds isolated from Tussilago farfara were identified as a (1:1) mixture of β sitosterol/stigmasterol (4), trans-caffeic acid (7), kaempferol (8), quercetin (9), kaempferol-3-O-glucoside (10), loliolide (11), a (4:1) mixture of p-coumaric acid/4-hydroxybenzoic acid (12), p-coumaric acid (13). All compounds were identified following analyses of their physicochemical and spectroscopic data (MS, ¹H and ¹³C-NMR) and by comparison with published data. This is the first report of the isolation of n-nonacosane (1), isololiolide (5), melitensin (6) and kaempferol-3-O-glucoside (10) from Arctium lappa, and of loliolide (11) from Tussilago farfara. Amongst the isolated compounds, the best activity was observed for p-coumaric acid (13) (MIC 31.3 μg/mL or 190.9 μM) alone and in mixture with 4-hydroxybenzoic acid (12) (MIC 62.5 μg/mL).

Conclusions

The above results provide for the first time some scientific evidence to support, to some extent, the ethno-medicinal use of Arctium lappa and Tussilago farfara as traditional antitubercular remedies.     

In vitro estrogenic activity of Asplenium trichomanes L. extracts and isolated compounds

Ethnopharmacological relevance

Asplenium trichomanes was used as an expectorant, anti-cough remedy, laxative, emmenagogue, abortifacient and for irregular menses.

Aim of the study

To investigate the in vitro estrogenic activity of Asplenium trichomanes extracts and isolated compounds and their ability to activate ERα and ERβ.

Materials and methods

Leaves infusion (IF), decoction (DC) and methanol extract (ME) were prepared. MCF7/EREluc cell line which expresses endogenous ERα, and SK-NBE cells transiently transfected with the estrogen receptors (ERα and ERβ) were used for the estrogenic activity assays. Phytochemical investigations were performed (CC, HPLC, etc.) and structure of isolated compounds were achieved on the basis of 1D and 2D NMR techniques and HR-MS spectrometry.

Results

IF and ME were active in our MCF7 model; selectivity for the ERβ receptor was observed in the SK-NBE test. Two new phenol derivatives, 4-vinyl-phenol-1-O-[α-l-rhamno(1 → 6)-β-d-glucopyranosyde] (1) and kaempferol-3-O-α-[2′acetyl]-arabinofuranosyl-7-O-α-l-rhamnopyranoside (2) were isolated with six known compounds (3–8). Compounds 2–4, 7 and 8 showed selectivity for the activation of the ERβ receptor although with a moderate activity compared with 17-β-estradiol.

Conclusion

Further investigations about the estrogenic effects of this plant are needed but our data can, at least in part, explain some of its traditional use as emmeagogue.     

Antimicrobial activity of the methanolic extract and compounds from Morus mesozygia stem bark

Aim of the study

This study was aimed at investigating the antimicrobial activity of the methanolic extract (MMB) and compounds isolated from the stem bark of Morus mesozygia, namely 3β-acetoxyurs-12-en-11-one (1), moracin Q (2), moracin T (3), artocarpesin (4), cycloartocarpesin (5), moracin R (6), moracin U (8), moracin C (9), and moracin M (10).

Materials and Methods

The liquid microdilution assay was used in the determination of the minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC), against nine bacterial and two fungal species.

Results

The results of the MIC determination showed that the compounds 3, 4, 8 and 9 were able to prevent the growth of all tested microbial species. All other samples showed selective activities. Their inhibitory effects were noted on 90.9% studied organisms for the crude extract, 81.8% for compound 6, 72.7% for compound 10, 63.6% for compound 1, 54.5% for compound 5, and 45.5% for compound 2. The lowest MIC value of 39 μg/ml was obtained with the crude extract against Escherichia coli. The corresponding value for compounds (5 μg/ml) was registered with compound 9 on Shigella dysenteriae and compound 3 on E. coli, S. dysenteriae, Pseudomonas aeruginosa, Salmonella typhi and Bacillus cereus. The lowest MIC value (39 μg/ml) observed with the crude extract (on E. coli) was only eightfold greater than that of gentamycin used as reference antibiotic (RA) while the corresponding value (5 μg/ml) recorded with compounds 3 and 9 was equal to that of RA on the corresponding microorganisms.

Conclusions

The obtained results highlighted the interesting antimicrobial potency of M. mesozygia as well as that of the studied compounds, and provided scientific basis for the traditional use of this species.     

Estrogenic and serotonergic butenolides from the leaves of Piper hispidum Swingle (Piperaceae)

Ethnopharmacological relevance

Our previous work has demonstrated that several plants in the Piperaceae family are commonly used by the Q’eqchi Maya of Livingston, Guatemala to treat amenorrhea, dysmenorrhea, and pain. Extracts of Piper hispidum Swingle (Piperaceae), bound to the estrogen (ER) and serotonin (5-HT7) receptors.

Aim of the study

To investigate the estrogenic and serotonergic activities of Piper hispidum extracts in functionalized assays, identify the active chemical constituents in the leaf extract, and test these compounds as agonists or antagonists of ER and 5-HT7.

Materials and methods

The effects of the Piper hispidum leaf extracts were investigated in estrogen reporter gene and endogenous gene assays in MCF-7 cells to determine if the extracts acted as an estrogen agonist or antagonist. In addition, the active compounds were isolated using ER- and 5-HT7 receptor bioassay-guided fractionation. The structures of the purified compounds were identified using high-resolution LC–MS and NMR spectroscopic methods. The ER- and 5-HT7-agonist effects of the purified chemical constituents were tested in a 2ERE-reporter gene assay in MCF-7 cells and in serotonin binding and functionalized assays.

Results

Three butenolides including one new compound (1) were isolated from the leaves of Piper hispidum, and their structures were determined. Compound 1 bound to the serotonin receptor 5-HT₇ with IC₅₀ values of 16.1 and 8.3 μM, respectively, and using GTP shift assays, Compound 1 was found to be a partial agonist of the 5-HT₇ receptor. The Piper hispidum leaf extracts, as well as Compounds 2 and 3 enhanced the expression of estrogen responsive reporter and endogenous genes in MCF-7 cells, demonstrating estrogen agonist effects.

Conclusions

Extracts of Piper hispidum act as agonists of the ER and 5-HT₇ receptors. Compound 1, a new natural product, identified as 9,10-methylenedioxy-5,6-Z-fadyenolide, was isolated as the 5-HT₇ agonist. Compounds 2 and 3 are reported for the first time in Piper hispidum, and identified as the estrogen agonists. No inhibition of CYP450 was observed for any of these compounds in concentrations up to 1 μM. These activities are consistent with the Q’eqchi traditional use of the plant for the treatment of disorders associated with the female reproductive cycle.     

Antimicrobial activity of the crude extract,fractions and compounds from stem bark of Ficus ovata (Moraceae)

Aim of the study

This study was designed to investigate the antimicrobial activities of the methanol extracts from the stem bark of Ficus ovata (FOB), fractions (FOB1–6) and compounds isolated following bio-guided fractionation [3-friedelanone (1), taraxeryl acetate (2), betulinic acid (3), oleanoïc acid (4), 2-hydroxyisoprunetin (5), 6,7-(2-isopropenyl furo)-5,2,4-trihydroxyisoflavone (6), Cajanin (7) and protocatechuic acid (8)].

Materials and Methods

The micro-dilution method was used for the determination of the minimal inhibition concentration (MIC) and the minimal microbicidal concentration (MMC) against fungi (two species), Gram-positive (three species) and Gram-negative bacteria (five species).

Results

The results of the MIC determinations indicated that the crude extract (FOB), fractions FOB2 and FOB4 as well as compound 5 were active on the entire studied organisms. Other samples showed selective activity, fractions FOB1, FOB3 and FOB5 being active against 50% of the tested microbial species while FOB6 was active on 40%. Compounds 8, 6, 2 and 7 prevented the growth of 80%, 70%, 50% and 20% of the organisms respectively. The lowest MIC value (156g/ml) observed with the crude extract was recorded on Streptococcus faecalis, Candida albicans and Microsporum audouinii. The corresponding value for fractions (39 μg/ml) was noted with FOB4 against Staphylococcus aureus, while that of the tested compounds (10 μg/ml) was observed with compound 8 on Microsporum audouinii. The results of the MMC determination suggested that the cidal effect of most of the tested samples on the studied microorganisms could be expected.

Conclusions

The overall results provided evidence that the studied plant extract, as well as some of the isolated compounds might be potential sources of new antimicrobial drug.     

In vitro activity of Tridax procumbens against promastigotes of Leishmania mexicana

Ethnopharmacological relevance

Tridax procumbens is an active herb against leishmaniasis.

Aim of the study

Leishmaniasis is a group of diseases caused by Leishmania protozoa. We investigated the antileishmanial activity of Tridax procumbens extracts and a pure compound against promastigotes of Leishmania mexicana, the causative agent of cutaneous leishmaniasis in the New World.

Materials and methods

Extracts and (3S)-16,17-didehydrofalcarinol (1) were obtained by chromatographic methods from Tridax procumbens, and the latter identified by spectroscopic analysis. The effect of these extracts and 1 on the growth inhibition of promastigotes of Leishmania mexicana was evaluated. In order to test the safety of extracts and 1, mammalian cells were treated with them, and cell viability was assessed using trypan blue and MTT.

Results

We demonstrated that extracts of Tridax procumbens and 1 showed a pronounced activity against Leishmania mexicana. The methanol extract inhibited promastigotes growth of Leishmania mexicana with a 50% inhibitory concentration (IC₅₀) of 3 μg/ml, while oxylipin 1 exhibited the highest inhibition at IC₅₀ = 0.478 μg/ml.

Conclusions

In this study we report the biological activity of extracts and (3S)-16,17-didehydrofalcarinol (1), obtained from Tridax procumbens, on the promastigote form of Leishmania mexicana, with no effect upon mammalian cells.     

Non-toxic melanin production inhibitors from Garcinia livingstonei (Clusiaceae)

Ethnopharmacological relevance

The stem bark of Garcinia livingstonei is used traditionally as a skin lightening agent.

Aim of the study

To isolate and identify compounds responsible for the observed skin lightening activity of Garcinia livingstonei and to evaluate their cytotoxicity.

Materials and methods

Constituents of the stem bark and fruits of Garcinia livingstonei were isolated using chromatographic techniques and structures were determined using 1D and 2D NMR and MS analysis. MeWo cells were used to evaluate the cytotoxicity and impact on melanin levels of extracts and compounds isolated, in vitro.

Results

Twelve known compounds, morelloflavone (1), morelloflavone-7″-sulphate (2), guttiferone A (3), sargaol (4), isojacareubin (5), 6-deoxyisojacareubin (6) and in addition to the common triterpenoids, betulin, betulin aldehyde, lupeol, lupenone, euphol and stigmasterol were isolated in this investigation. Morelloflavone, morelloflavone-7″-sulphate and sargaol, were found to be considerably less cytotoxic and more effective as skin lightening agents than hydroquinone.

Conclusions

A range of compounds was isolated from the stem bark and fruit of Garcinia livingstonei. Although the bark extract contained the cytotoxic guttiferone A, it was found to be less toxic than hydroquinone, and morelloflavone, the 7″-sulphate derivative and sargaol show potential for development as depigmentation/skin lightening agents.     

UPLC/MS/MS method for quantification and cytotoxic activity of sesquiterpene lactones isolated from Saussurea lappa

Ethnopharmacological relevance

Saussurea lappa (Asteraceae) roots have been reputed for the usage in traditional medicinal systems of India, China and Japan for the treatment of various kinds of disorders such as anti-ulcer, anti-convulsant, anti-cancer, hepatoprotective, anti-arthritic and anti-viral activities.

Materials and methods

Compounds were isolated using a column chromatographic technique. The root extract, fractions and isolated compounds were tested for cytotoxicity against A549 (human lung carcinoma) and C-6 (rat glioma) cells using the Sulphorhodamine B assay. Chromatographic separations of active sesquiterpene lactones were accomplished on BEH-HSS-T3 column at 25 °C.

Results

Phytochemical investigation of Saussurea lappa root extract resulted in the isolation of isoalantolactone (1), β-cyclocostunolide (2) α-cyclocostunolide (3), 4-hydroxy-3,5-dimethoxycinnamyl-9-O-β-d-glucopyranoside (4), sucrose (5), and alantolactone (6). Their structures were determined by spectroscopic means. Ethanolic extract, chloroform fraction, compounds 1, 2, 3 and 6 possessed significant activity against both tested cells. The quantification was performed using the transitions of m/z 233/105 for isoalantolactone and m/z 233/105 for alantolactone respectively. Costunolide and dehydrocostus lactone were also characterised by comparison of MS/MS fragmentation pattern.

Conclusions

This is the first study on simultaneous quantification of isoalantolactone and alantolactone by the UPLC/MS/MS method in Saussurea lappa. Our study against A549 and C-6 cells showed higher cytotoxicity. It is suggested that roots of Saussurea lappa might be a potential source of anticancer compounds.     

Antiangiogenic activity of Tripterygium wilfordii and its terpenoids

Ethnopharmacological relevance

Tripterygium wilfordii Hook. f. (Celastraceae) has been traditionally used as folk medicine for centuries in China for the treatment of immune-inflammatory diseases.

Aim of the study

This study aimed to assess the antiangiogenic activities which support the therapeutic use of Tripterygium wilfordii and its terpenoids for angiogenesis disease such as cancer.

Materials and methods

The ethanol extract of Tripterygium wilfordii and subsequent fractions were evaluated on an in vivo antiangiogenic zebrafish embryo model.

Results

Three antiangiogenic terpenoids were isolated by bioassay-guided purification, namely, celastrol (4), cangoronine (5) and triptolide (7). Among them, triptolide manifested the most potent antiangiogenic activity against vessel formation by nearly 50% at 1.2 μM. Semi-quantitative RT-PCR analysis revealed that triptolide dose- and time-dependently reduced the mRNA expression of angiopoietin (angpt)2 and tie2 in zebrafish, indicating the involvement of angpt2/tie2 signaling pathway in the antiangiogenic action of triptolide.

Conclusions

The discovery of an alternative pathway further confirms the value of ethnopharmacological investigations into traditional botanicals for leads for potential drug development.     

Antifungal activity of the benzo[c]phenanthridine alkaloids from Chelidonium majus Linn against resistant clinical yeast isolates

Ethnopharmacological relevance

The herb of Chelidonium majus Linn is known to possess a variety of biological activities and applied in the therapy of various infectious diseases.

Aim of the study

To evaluate the in vitro antifungal activity of the active components from Chelidonium majus against clinical drug-resistant yeast isolates.

Materials and methods

Active compounds were obtained using bioassay-guided method. Six species of yeast fungi were exposed to the compounds. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined according to the standard broth microdilution method.

Results

Of the six compounds determined, 8-hydroxydihydrosanguinarine (1) and 8-hydroxydihydrochelerythrine (2) demonstrated potent activity with the MIC ranges of 2–80 and 4–100 μg/mL, respectively. Dihydrosanguinarine (3), dihydrochelerythrine (4), sanguinarine (5) and chelerythrine (6) had some degree of antifungal activity.

Conclusions

The overall results provided important information for the potential application of the 8-hydroxylated alkaloids from Chelidonium majus in the therapy of serious infection caused by drug-resistant fungi.     

Sedative activity of hexane extract of Keampferia galanga L. and its active compounds

Ethnopharmacological relevance

It is well known that fragrance impacts behaviors and autonomic functions, and is increasingly used as relaxant, carminative, as well as sedative in aromatherapy. Kaempferia galanga L. is one of the popular traditional aromatic medicinal plants used in tropics and subtropics of Asia including China, Japan and Indochina.

Aim of the study

The aim of present study was to investigate sedative effects of hexane extract of Kaempferia galanga L.and 2 active aromatic compounds (compound 1: ethyl trans-p-methoxycinnamate and compound 2: ethyl cinnamate ) included in the extyract by means of inhalation in mice.

Materials and methods

Sedative activity was assessed by inhalation of the hexane extract and two major aromatic compounds.

Results

Inhalation of hexane extract at the doses of 1.5 and 10 mg showed significant reduction of locomotor activity, indicating considerable sedative and relaxant effects. Compound 1 and 2 were proved to possess sedative effects at 0.0014 mg and 0.0012 mg respectively.

Conclusions

These results suggest the promising application of Kaempferia galanga L. and its constituents in aromatherapy.     

Phenological and geographical influence in the concentration of selected bioactive 4-phenylcoumarins and chlorogenic acid in Hintonia latiflora leaves

Ethnopharmacological relevance

Hintonia latiflora is a Mexican medicinal plant with well-documented ethnomedical record comprising more than 400 years; in modern Mexico is used for treating several maladies such as diabetes and gastric ulcers. Although the pharmacological actions of the stem-bark and leaves have been demonstrated, the phenological and geographical effect on the concentration of active principles remains unexplored.

Aim of the study

The main goals of this study were to analyze the amount of selected 4-phenylcoumarins and chlorogenic acid in the leaves in order to assess the best harvesting period, and consequently their pharmacological efficacy. In addition, the preclinical antidiabetic efficacy of the infusion of the leaves was corroborated using standard pharmacological tests.

Materials and methods

The aqueous extracts from the leaves of Hintonia latiflora were prepared by infusion. For phenological and geographical comparison, leaves of Hintonia latiflora were collected in two different regions in Chihuahua and Michoacán. The material was analyzed by UPLC applying an analytical method that developed and validated for this purpose following the ICH guidelines. Investigation of the antidiabetic action was accomplished using an acute hypoglycemic test and oral glucose and sucrose tolerance tests.

Results

The validated analytical method was successfully applied for quantifying chlorogenic acid (1) and 4-phenylcoumarins (2–5) in the leaves of 12 different batches (1–12) during one-year period, and seven different batches for each geographical region; the concentration of the metabolites at the phenological cycle was significantly different, their concentration increased during the pre-senescence phase whereas in the leaf renovation stage the highest concentration of 2–5 was reached. The overall analysis of the active compounds concentration between the two populations investigated seems to be less important than the phenological variations. The aqueous extract of the leaves of Hintonia latiflora exerted its antidiabetic effect by different mechanisms showing comparable effect to the organic extract.

Conclusions

The findings of the present investigation reveal that the best harvest season for the leaves of Hintonia latiflora is between the leaves renovation and senescence stages avoiding the flowering period. In addition, no significant differences were found among the two different geographical populations analyzed. The infusions of the leaves, rich in 4-phenylcoumarins and chlorogenic acid, showed comparable antidiabetic action than the organic extract.