Lignan Glycosides Research Articles

Three New Lignan Glycosides from the Firmiana simplex.

In our quest for structurally intriguing compounds from Korean medicinal plant sources, chromatographic separation of the 80% MeOH extract from Firmiana simplex resulted in the isolation and identification of three new lignan glycosides (1-3), together with six known lignan glycosides (4-9). The structures of 1-3 were determined on the basis of spectroscopic analyses, including extensive 2D-NMR and enzyme hydrolysis. Nitric oxide (NO) production was evaluated in the lipopolysaccharide-activated microglial cell line, BV-2 to investigate the anti-neuroinflammatory effects of the isolated compounds (1-9). Compound 7 marginally inhibited NO levels with IC50 values of 59.83 µM.

(+)‑pinoresinol‑O‑β‑D‑glucopyranoside from Eucommiaulmoides Oliver and its anti‑inflammatory and antiviral effects against influenzaA (H1N1) virus infection.

Eucommiaulmoides Oliver (Du-Zhong) is an ancient Chinese herbal remedy used for the treatment of various diseases. To date, the effects of its constituent lignans on influenza viruses remain to be elucidated. In the present study, a lignan glycoside was isolated and purified from Eucommiaulmoides Oliver. Its structures were identified via extensive spectroscopic analysis, and its antiviral and anti‑inflammatory activities, specifically against influenza viruses, were determined via a cytopathic effect (CPE) assay, plaque‑reduction assays, a progeny virus yield reduction assay, reverse transcription‑quantitative polymerase chain reaction analysis and a Luminex assay. Additionally, western blot analysis was performed to investigate the underlying mechanisms of its effects against influenza viruses. The chemical and spectroscopic methods determined the structure of lignan glycoside to be (+)‑pinoresinol‑O‑β‑D‑glucopyranoside. The CPE assay showed that (+)‑pinoresinol‑O‑β‑D‑glucopyranoside exerted inhibitory activities with 50% inhibition concentration values of 408.81±5.24 and 176.24±4.41µg/ml against the influenzaA/PR/8/34 (H1N1) and A/Guangzhou/GIRD07/09 (H1N1) strains, respectively. Its antiviral properties were confirmed by plaque reduction and progeny virus yield reduction assays. Additional mechanistic analyses indicated that the anti‑H1N1 virus‑induced effects of (+)‑pinoresinol‑O-β‑D-glucopyranoside were likely due to inactivation of the nuclear factor‑κB, p38 mitogen‑activated protein kinase and AKT signaling pathways. Furthermore, (+)‑pinoresinol‑O‑β‑D‑glucopyranoside exhibited pronounced inhibitory effects on the expression of influenza H1N1 virus‑induced pro‑inflammatory mediators, including tumor necrosis factor‑α, interleukin (IL)‑6, IL‑8 and monocyte chemoattractant protein1. The data obtained suggest that (+)‑pinoresinol‑O‑β‑D-glucopyranoside may be a candidate drug for treating influenza H1N1 virus infection.

Lignan Glycosides and Flavonoid Glycosides from the Aerial Portion of Lespedeza cuneata and Their Biological Evaluations.

Lespedeza cuneata (Fabaceae), known as Chinese bushclover, has been used in traditional medicines for the treatment of diseases including diabetes, hematuria, and insomnia. As part of a continuing search for bioactive constituents from Korean medicinal plant sources, phytochemical analysis of the aerial portion of L. cuneata led to the isolation of two new lignan glycosides (1,2) along with three known lignan glycosides (3–7) and nine known flavonoid glycosides (8–14). Numerous analysis techniques, including 1D and 2D NMR spectroscopy, CD spectroscopy, HR-MS, and chemical reactions, were utilized for structural elucidation of the new compounds (1,2). The isolated compounds were evaluated for their applicability in medicinal use using cell-based assays. Compounds 1 and 4–6 exhibited weak cytotoxicity against four human breast cancer cell lines (Bt549, MCF7, MDA-MB-231, and HCC70) (IC50 < 30.0 μM). However, none of the isolated compounds showed significant antiviral activity against PR8, HRV1B, or CVB3. In addition, compound 10 produced fewer lipid droplets in Oil Red O staining of mouse mesenchymal stem cells compared to the untreated negative control without altering the amount of alkaline phosphatase staining.

Novel sesquilignan and lignan glycoside from the twigs and leaves of Illicium majus

A novel sesquilignan compound (1), possesing an unusual carbon skeleton of aryltetralin unit linked with a C6-C3 unit and a five-membered ring by a C-7″ and C-4 linkage pattern via an oxygen atom, and a new lignan glycoside (2) have been isolated from the twigs and leaves of Illicium majus. Their structures were determined by spectroscopic analysis and chemical methods. The absolute configurations of 1 and 2 are confirmed by observing the circular dichroism. At 10 μM, Compounds 1 and 2 showed in Vitro inhibitory activity against the release of β-glucuronidase in rat polymorphonuclear leukocytes induced by platelet-activating factor.

Benzoxazinoid and indoxyl glycosides from Wrightia religiosa

A new class of secondary metabolites of the family Apocynaceae, benzoxazinoid, was reported for the first time from Wrightia religiosa. A new benzoxazinoid glycoside, (2S)-2-O-β-d-glucopyranosyl-2H-1,4-benzoxazin-3(4H)-one (2) and a new indole diglycoside, indoxyl 3-O-β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranoside (4) were isolated, together with twelve known compounds, including benzoxazinoid glycosides (1, 3), simple aromatic glycosides (5–8), a lignan glycoside (9), flavonol glycosides (10–13) and a megastigmane glucoside (14). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. A benzoxazinoid with (2S)-configuration was isolated for the first time from natural source.

Chemical Constituents from Cimicifuga dahurica and Their Anti-Proliferative Effects on MCF-7 Breast Cancer Cells

This study was designed to search for novel anti-cancer compounds from natural plants. The 70% ethanolic extract from the rizhomes of Cimicifuga dahurica (Turcz.) Maxim. (Ranunculaceae) was found to possess significant in vitro anti-proliferative effects on MCF-7 breast cancer cells. A phytochemical investigation using assay-guided fractionation of the ethanolic extract of C. dahurica resulted in the isolation of one new phenolic amide glycoside 3, two new lignan glycosides 4 and 7, one new 9,19-cycloartane triterpenoid glycoside 6, and thirteen known constituents 1, 2, 5, and 8–17. The structures of 3, 4, 6, and 7 were established using contemporary NMR methods and from their HRESIMS data. The anti-proliferative effects of isolated compounds were evaluated using the BrdU-proliferation kit. Five among the 17 isolated compounds showed significant anti-proliferative effects (p ≤ 0.05), wherein compound 7 showed the most significant anti-proliferative and cell cycle arresting effect (p ≤ 0.05) which followed a dose dependent manner. Western blot protein expression analysis showed a down expression of c-Myc and cyclin D1 which further elucidated the anti-proliferation mechanism of compound 7 while apoptotic effects were found in association with Bcl-2 family protein expression variations. Conclusively this study reports the isolation and identification of 17 compounds from C. dahurica, including four novel molecules, in addition to the fact that compound 7 possesses significant anti-proliferative and apoptotic effects in vitro that may require further exploration.

Anti-Inflammatory and Antinociceptive Studies of Hydroalcoholic Extract from the Leaves of Phyllanthus brasiliensis (Aubl.) Poir. and Isolation of 5-O-β-d-Glucopyranosyljusticidin B and Six Other Lignans.

The aim of this study was to investigate the chemical composition and the antiinflammatory/antinociceptive properties of the hydroalcoholic extract derived from the leaves of Phyllanthus brasiliensis (HEPB) in rodents. A new arylnaphthalene lignan glycoside, 5-O-β-d-glucopyranosyljusticidin B, together with six known lignans, were isolated from HEPB. 1D and 2D NMR experiments and HRMS were used to elucidate the structure of the new compound. HEPB toxicity and antinociceptive activity were evaluated through acute oral toxicity and formalin models in mice, respectively. The anti-inflammatory effects of HEPB were assessed using carrageenan- and dextran-induced paw edema models in rats. HEPB showed low toxicity. Oral administration of HEPB reduced paw edema induced by carrageenan, but not by dextran. HEPB and its fractions from FR6 to FR10 (FR6-10) inhibited the neurogenic and inflammatory phases of formalin-induced linking, demonstrating its antinociceptive activity. These results indicated that lignans from Phyllanthus brasiliensis exerted antinociceptive/anti-inflammatory effects not related to the histaminergic pathway.

New lignan glycosides from Cissus quadrangularis stems

Phytochemical investigation of Cissus quadrangularis stems led to the isolation of one new phenolic glycoside (1) and two new lignan glycosides (7 & 8) along with twelve known compounds (2–6 & 9–15). Their chemical structures were determined on the basis of extensive spectroscopic analysis using 1D, 2D NMR, and mass spectrometric analysis. Among the known compounds, 4–6, 9 and 12 were isolated for the first time from the genus Cissus whereas compounds 10, 11 and 13 for the first time from this plant.

Elucidation of micromolecular phenylpropanoid and lignan glycosides as the main antioxidants of Ginkgo seeds

Ginkgo biloba L. is a widely used medicinal plant that has a high concentration of its bioactive components, flavonoids and ginkgolides, in its leaves. Gingko seeds are also consumed as a functional food and medicine throughout the world to slow the ageing process. However, there have been few phytochemical studies of the phenylpropanoids from Ginkgo seeds. To elucidate the active components, we studied the antioxidant activities and related main compounds in Ginkgo seeds. Four main phenylpropanoids and lignans were isolated and identified from the antioxidative fraction and their antioxidant activities were measured. An HPLC/DAD-Q-TOF-MS/MS method was developed to identify the other minor phenylpropanoid and lignan glycosides to elucidate the antioxidant profile of Gingko seeds. Four compounds were identified by NMR and mass data, three of which (8, 17, and 28) exhibited substantial antioxidant activities (IC50: 67–100 μM). Sixteen minor compounds were tentatively identified based on their tandem mass spectrometry data and the fragmentation of four isolated standards from antioxidative n-butanol fraction. Fifteen compounds were reported in Ginkgo seeds for the first time, and compound 16 was tentatively identified as a new chemical structure. Thus, understanding their antioxidant profiles will lay the foundation for research and development of the health benefits of Ginkgo seeds.

A Strategy for Preparative Separation of 10 Lignans from Justicia procumbens L. by High-Speed Counter-Current Chromatography.

Ten compounds, including three lignan glycosides and seven lignans, were purified from Justicia procumbens L. in 8 h using an efficient strategy based on high-speed counter-current chromatography (HSCCC). The two-phase solvent system composed of petroleum–ethyl acetate–methanol–H2O (1:0.7:1:0.7, v/v) was firstly employed to separate the crude extract (320 mg), from which 19.3 mg of justicidin B (f), 10.8 mg of justicidin A (g), 13.9 mg of 6′-hydroxyjusticidin C (h), 7.7 mg of justicidin E (i), 6.3 mg of lignan J1 (j) were obtained with 91.3 mg of enriched mixture of compounds a–e. The enriched mixture (91.3 mg) was further separated using the solvent system consisting of petroleum–ethyl acetate–methanol–H2O (3:3.8:3:3.8, v/v), yielding 12.1 mg of procumbenoside E (a); 7.6 mg of diphyllin-1-O-β-d-apiofuranoside (b); 7.4 mg of diphyllin (c); 8.3 mg of 6′-hydroxy justicidin B (d); and 7.9 mg of diphyllin acetyl apioside (e). The purities of the 10 components were all above 94%, and their structures were identified by NMR and ESI-MS spectra. The results demonstrated that the strategy based on HSCCC for the separation of lignans and their glycosides was efficient and rapid.

Seven new lignan glycosides from the branches of Alangium kurzii Craib var. laxifolium

Seven new lignan glycosides (1–3, 8–10, and 14) and 17 known compounds were isolated from the branches of Alangium kurzii Craib var. laxifolium. Their structures were established by spectroscopic analysis and circular dichroism (CD) and X-ray analysis. The isolated compounds were evaluated for their antibacterial activities against Staphylococcus aureus CI1011, Streptococcus suis CI1608, Salmonella gallinarum CI0912, Enterococcus faecalis CI1304, Aeromonas hydrophila CI1008, Escherichia coli CI151012, Vibrio parahaemolyticus CI150506, Klebsiella pneumoniae CI131216, Pseudomonas aeruginosa CI1011, Staphylococcus epidermidis CI1110, and Streptococcus agalactiae CI1302. Their minimum inhibitory concentrations (MICs) were determined by serial dilution in 96-well culture plates.

Potent Inhibitor of Drug-Resistant HIV-1 Strains Identified from the Medicinal Plant Justicia gendarussa

Justicia gendarussa, a medicinal plant collected in Vietnam, was identified as a potent anti-HIV-1 active lead from the evaluation of over 4500 plant extracts. Bioassay-guided separation of the extracts of the stems and roots of this plant led to the isolation of an anti-HIV arylnaphthalene lignan (ANL) glycoside, patentiflorin A (1). Evaluation of the compound against both the M- and T-tropic HIV-1 isolates showed it to possess a significantly higher inhibition effect than the clinically used anti-HIV drug AZT. Patentiflorin A and two congeners were synthesized, de novo, as an efficient strategy for resupply as well as for further structural modification of the anti-HIV ANL glycosides in the search for drug leads. Subsequently, it was determined that the presence of a quinovopyranosyloxy group in the structure is likely essential to retain the high degree of anti-HIV activity of this type of compounds. Patentiflorin A was further investigated against the HIV-1 gene expression of the R/U5 and U5/gag transcripts, and the data showed that the compound acts as a potential inhibitor of HIV-1 reverse transcription. Importantly, the compound displayed potent inhibitory activity against drug-resistant HIV-1 isolates of both the nucleotide analogue (AZT) and non-nucleotide analogue (nevaripine). Thus, the ANL glycosides have the potential to be developed as novel anti-HIV drugs.

Lignan glycosides and sucrose esters from roots of Securidaca inappendiculata

Nine compounds, including five lignan glycosides (1-5), three sucrose esters (6-8), and one organic acid ester (9), were isolated from the ethanol extract of the roots of Securidaca inappendiculata by various chromatographic methods including silica gel, MPLC and preparative HPLC. Their structures were elucidated as acernikol-4″-O-β-D-glucopyranoside (1), (7R, 8S)-dihydrodehydrodiconiferyl alcohol 9-O-β-D-glucopyranoside (2), (7R, 8S)-dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside (3), (7R, 8S)-dihydrodehydrodiconiferyl alcohol 9'-O-β-D-glucopyranoside (4), (7R, 8S)-5-methoxydihydrodehy-drodiconiferyl alcohol 4-O-β-D-glucopyranoside (5), 3, 6'-O-diferuloylsucrose (6), 3-O-feruloyl-6'-O-sinapoylsucrose (7), sibricose A5 (8), and mehyl ferulate (9) on the basis of 1H-, 13C-NMR and MS experiments. Compounds 1-5, 8, and 9 were isolated from the Securidaca genus for the first time. Compounds 2, 3, and 7 exhibited weak cytotoxic activities against Hela and MCF-7 cell lines.

New lignan glycosides from the root barks of Litsea glutinosa

An investigation on the chemical constituents in the root barks of Litsea glutinosa was performed for the first time. Three new lignan glycosides named Litseasins A–C (1–3), together with a known one (4), were obtained. The structures of the new compounds were established through extensive spectroscopic analyses including HR-ESI–MS, NMR, and circluar dichroism (CD). The new compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induce nitric oxide (NO) production in RAW264.7 murine macrophage cells. However, these compounds showed no inhibition on LPS-induced NO productions.

Lignan glycosides from the Rhizomes of Smilax trinervula and their Biological activities

Phytochemical investigation of the rhizomes of Smilax trinervula led to isolation and structure elucidation of eight lignan glycosides, including five new lignans, namely, (7S, 8R, 8′R)-4, 4′, 9-trihydroxy-3, 3′, 5, 5′-tetramethoxy-7, 9′-epoxylignan-7′-one 4′-O-β-d-glucopyranoside (1), (7S, 8R, 8′R)-4, 4′, 9-trihydroxy-3, 3′, 5, 5′-tetramethoxy-7, 9′-epoxylignan-7′-one 4-O-β-d- glucopyranoside (2) (7S, 8R)-4, 9, 9′-trihydroxy-3, 3′, 5-trimethoxy-4′, 7-epoxy-8, 5′-neolignan 9′-O-β-d-glucopyranoside (3), (7R, 8R)-4, 9, 9′-trihydroxy-3, 5-dimethoxy-7.O.4′, 8.O.3′- neolignan 9′-O-β-d-glucopyranoside (4), and (7S, 8R)-4, 9, 9′-trihydroxy-3, 3′, 5-trimethoxy-8, 4′-oxy-neolignan 4-O-β-d-glucopyranoside (5), along with three known compounds (6-8). Their structures were established mainly on the basis of 1D and 2D NMR spectral data, ESI–MS and comparison with the literature. Compounds 1-8 were tested in vitro for their cytotoxic activity against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116, Lovo). Compounds 3 and 5 exhibited cytotoxic activity against Lovo cells, with IC50 value of 10.4μM and 8.5μM, respectively.

Evaluation of Antiulcer and Cytotoxic Potential of the Leaf, Flower, and Fruit Extracts of Calotropis procera and Isolation of a New Lignan Glycoside.

Calotropis procera is traditionally used for treating many diseases including ulcers and tumors. It was thus deemed of interest to investigate and compare the antiulcer and cytotoxic activities of C. procera leaf, flower, and fruit extracts in an attempt to verify its traditional uses. Phytochemical studies on the fruits, flowers, and leaves of C. procera, collected from the desert of Saudi Arabia, led to the isolation of one new lignan 7′-methoxy-3′-O-demethyl-tanegool-9-O-β-d-glucopyranoside and five known compounds from the flowers, four compounds from leaves, and a flavonoid glycoside and a lignan glycoside from the fruits. The structures of compounds were determined by spectroscopic techniques. Ethanol extracts of the three parts of C. procera were evaluated for their antiulcer activity and we found that the leaf extract possessed a powerful antiulcer activity which could be considered as a promising drug candidate. All the extracts and the isolated compounds were evaluated for their cytotoxic activity against MCF-7, HCT-116, HepG-2, and A-549 human cancer cell lines. Compound 2 was highly active on all the cell lines, whereas compounds 5 and 11 were more selective on colon and liver cell lines. Compound 10 demonstrated a significant activity on liver and lung cancer cell lines.

Antibacterial activities of chemical constituents from the aerial parts of Hedyotis pilulifera

Context: Hedyotis pilulifera (Pit.) T.N. Ninh (Rubiaceae) has been used in Vietnamese ethnomedicine; the methanol extract exhibited antibacterial activity in our preliminary screening. Objectives: In this study, compounds from H. pilulifera were isolated and their antibacterial activity in vitro was evaluated. Materials and methods: The aerial parts of H. pilulifera (1.4 kg) were extracted with MeOH, suspended in water and ethyl acetate extract was chromatographed on a silica gel column. The structures of isolated compounds were elucidated by the combination analyses of spectroscopy including 1D-, 2D-NMR, HRMS and in comparison with the reported NMR data in the literature. All isolated compounds were evaluated for inhibitory effect using the microdilution method toward Staphylococcus aureus, Bacillus subtilis and Mycobacterium smegmatis, and MIC values were determined. Results: Twenty compounds were isolated, including five triterpenoids, two steroids, two aromatic compounds, three fatty acids, one quinone derivative, one lignan glycoside, one ceramide and five glycolipids. Among these, oleanolic acid showed significant antibacterial activity against M. smegmatis with the MIC value of 2.5 μg/mL. Remarkably, rotungenic acid showed strong activity against S. aureus, B. subtilis, M. smegmatis with MIC values of 2.5, 2.5 and 1.25 μg/mL, respectively. Rotundic acid exhibited significant antibacterial activity against B. subtilis with the MIC value of 5 μg/mL. To the best of our knowledge, the antibacterial activity of rotungenic acid, stigmast-4-ene-3,6-dione and (2S,3S,4R,2′R)-2-(2′-hydroxytetracosanoylamino) octadecane-1,3,4-triol was reported for the first time. Conclusions: Oleanolic acid, rotungenic acid, and rotundic acid were considered to be useful for developing new antimicrobial therapeutic agents for human.

Biotransformation of lignan glycoside to its aglycone by Woodfordia fruticosa flowers: quantification of compounds using a validated HPTLC method

Context: Saraca asoca Linn. (Caesalpiniaceae) is an important traditional remedy for gynaecological disorders and it contains lyoniside, an aryl tetralin lignan glycoside. The aglycone of lyoniside, lyoniresinol possesses structural similarity to enterolignan precursors which are established phytoestrogens. Objectives: This work illustrates biotransformation of lyoniside to lyoniresinol using Woodfordia fruticosa Kurz. (Lythraceae) flowers and simultaneous quantification of lyoniside and lyoniresinol using a validated HPTLC method. Materials and methods: The aqueous extract prepared from S. asoca bark was fermented using W. fruticosa flowers. The substrate and fermented product both were simultaneously analyzed using solvent system:toluene:ethyl acetate:formic acid (4:3:0.4) at 254 nm. The method was validated for specificity, accuracy, precision, linearity, sensitivity and robustness as per ICH guidelines. Results: The substrate showed the presence of lyoniside, however, it decreased as the fermentation proceeded. On 3rd day, lyoniresinol starts appearing in the medium. In 8 days duration most of the lyoniside converted to lyoniresinol. The developed method was specific for lyoniside and lyoniresinol. Lyoniside and lyoniresinol showed linearity in the range of 250–3000 and 500–2500 ng. The method was accurate as resulted in 99.84% and 99.83% recovery, respectively, for lyoniside and lyoniresinol. Conclusion: Aryl tetralin lignan glycoside, lyoniside was successfully transformed into lyoniresinol using W. fruticosa flowers and their contents were simultaneously analyzed using developed validated HPTLC method.

New lignan glycosides from Justicia procumbens

Four new lignan glycosides (1–4), named procumbenosides I, K, L, and M, together with cleistanthin B (5) reported for the first time in the genus Justicia, and 5 other known arylnaphthalene lignan glycosides (6–10) were isolated from the whole plant of Justicia procumbens. The structures of the new compounds were elucidated by extensive one-dimensional (1D) and two-dimensional (2D) NMR experiments and mass spectrometry. Procumbenoside M (4) was a rare sesquilignan glycoside never previously reported in the species of Justicia. The paper also provided insight into the conformational equilibria existing in the lignan glycosides of the plant.

Wasabisides A-E, Lignan Glycosides from the Roots of Wasabia japonica.

Five new lignan glycosides, wasabisides A-E (1-5), and four known phenolic compounds (6-9), were isolated from the roots of Wasabia japonica. The chemical structures of the new compounds (1-5) were determined through spectroscopic analysis and chemical methods. All isolated compounds (1-9) were evaluated for their potential neuroprotective effects through induction of nerve growth factor in C6 glioma cells, for their effects on nitric oxide levels in lipopolysaccharide-stimulated murine microglia BV2 cells, and for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and BT549).