A new phloroglucinol diglycoside derivative from Hypericum japonicum Thunb

Novel compounds of Djulis (Chenopodium formosanum Koidz) increases collagen, antioxidants, inhibits adipogenesis

Djulis (Chenopodium formosanum Koidz), is rich in nutrients and contains various bioactive components such as polyphenols and alkaloids. The new compound has a broad application prospect, including food additives, health products, drugs, etc. The purpose of this study was to find out new compounds from Djulis. It was found that 24 compounds including 7 phenols, 11 flavonoids, 4 plant alkaloids, 2 sterols. Among those, TCI-CF-22-S (Methyl 3,6-dihydroxy-2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxylate), TCI-CF-23-S (Methyl 6-hydroxy-2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxylate), TCI-CF-24-S (Kaempferol-3-O-b-D-apifuranosyl-(1→2)-a-L-arabinopyranoside) were isolated from djulis sources for the first time, and the structures of compounds were assigned by 1D, 2D NMR spectroscopy. TCI-CF-01(Caffeic acid), TCI-CF-02 (20-Hydroxyecdysone), TCI-CF-03 (Japonicone), TCI-CF-04 (3,4-Dihydroxyphenylacetiate), TCI-CF-05 (Quercetin-3-O-rutinoside-7-O-rhamnopyranoside), TCI-CF-06 (Guanosine), TCI-CF-07(Adenine), TCI-CF-08 (Coumaric acid) increased collagen production, and TCI-CF-03 (Japonicone), TCI-CF-04 (3,4-Dihydroxyphenylacetiate), TCI-CF-06 (Guanosine), TCI-CF-17 (Rutin), TCI-CF-20 (Protocatechuic acid) decreased advanced glycation end products (AGEs). In addition, TCI-CF-22-S (Methyl 6-hydroxy-2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxylate), TCI-CF-23-S (Methyl 3,6-dihydroxy-2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxylate) inhibited the formation of fatty oil droplets. Djulis has 24 compounds that may have various applications, including increasing collagen production and reducing advanced glycation end products and fatty oil droplets.

New 4',5'-methylenedioxyflavone derivatives from the whole plant of sarcandra glabra

Two new natural products named 5,7-dihydroxy-3,3',6,8-tetramethoxy-4',5'-methylenedioxyflavone (1) and 3,3',5,7-tetramethoxy-4',5'-methylenedioxyflavone (2), along with thirteen known compounds, β-sitosterol (3), desmethoxyyangonin (4), hexadecane (5), 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide (6), 2'6'-dihydroxy-4'-methoxydihydrochalcone (7), cardamonin (8), 3,3',5,6,7,8-hexamethoxy-4',5'-methylenedioxyflavone (9), isofraxidin (10), aniba dimer A (11), 3,3',4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (12), quercetin (13), quercitrin (14) and isoquercitrin (15) were isolated from Sarcandra glabra (Thunb.) Nakai by various chromatographic methods. Compounds 1, 2, 4, 6, 11, and 12 were isolated from S. glabra for the first time. Their chemical structures were identified through the analysis of NMR and HR-MS spectra. The anti-inflammatory and cytotoxic activities of compounds 1-15 were evaluated in cell assays. The results indicated that compounds 1, 7, 8, 10, 14, and 15 significantly inhibited the NO production in LPS-induced RAW 264.7 murine macrophage cells. Moreover, compounds 1, 3, 4, 7, 8, 9, 10 and 12 exhibited a cytotoxic effect on the human HepG2 cell line.

Euphormins A and B, New Pyranocoumarin Derivatives from Euphorbia formosana Hayata, and Their Anti-Inflammatory Activity

Euphormin-A (1) and euphormin-B (2), two new pyranocoumarin derivatives, and forty known compounds (3–42) were isolated from Euphorbia formosana Hayata (Euphorbiaceae). The chemical structures of all compounds were established based on spectroscopic analyses. Several isolates were evaluated for their anti-inflammatory activity. Compounds 1, 2, 10, 18, 25, and 33 significantly inhibited against superoxide anion generation and elastase release by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Furthermore, compounds 25 and 33 displayed the most potent effects with IC₅₀ values of 0.68 ± 0.18 and 1.39 ± 0.12 µM, respectively, against superoxide anion generation when compared with the positive control (2.01 ± 0.06 µM).

Structural characterization of three cytotoxic steroidal saponins from the leaves of Agave desmetiana hort

Three steroidal saponins detected by LC-MS were isolated from the leaves of Agave desmetiana hort. The three saponins were characterized as; Tigogenin 3 - [{O - β - D - xylopyranosyl (1 → 2) - α - L-rhamnopyranosyl (1 → 3)}-β-D- glucopyranoside), Tigogenin- 3 - ([O- α -L-rhamnopyranosyl (1 → 3) - β - D - glalactopyranosyl (1 → 2)] - β - D - glucopyranoside) and Tigogenin- 3 - ([{O - α - L - rhamnopyranosyl (1 → 4)} - β - D - galactopyranosyl (1 → 3) - β - D - xylopyranosyl (1 → 2)] - β - D - glucopyranoside). Identification and structure elucidation of the isolates were done via 1D and 2D NMR techniques, and chemical methods. Cytotoxic activity for the crude saponins and the three isolated compounds were evaluated against Hepg-2 and Mcf-7 cell lines. Compound 2 proved to be the most cytotoxic against tested cell lines with an IC₅₀ 2.97 and 2.49 μg/ml respectively.

New dimeric phloroglucinol derivatives from Agrimonia pilosa and their hepatoprotective activities

Five new dimeric phloroglucinol derivatives, agrimones A - E (1-5), were isolated from the whole plant of Agrimonia pilosa. Their structures including absolute configurations were determined by a series of spectroscopic data (UV, IR, HR-ESI-MS, 1D and 2D NMR), complemented with the comparison of the experimental and calculated ECD spectra, and gauge-independent atomic orbital (GIAO) NMR calculations. Notably, compounds 1 and 2 represent a highly oxidized 6/6/6 tricyclic ring skeleton based on the cis-fused paraquinone and chroman. Compounds 1a, 4, and 5 exhibited moderate hepatoprotective activities against APAP-induced HepG2 cell injury at 10 μM.

Investigation of Dalea parryi (Fabaceae) metabolites for anthelmintic activity against the human pathogenic hookworm Ancylostoma ceylanicum

The US Southwest plant Dalea parryi (Fabaceae) was investigated as part of an ongoing study of the potential of plant compounds for anthelmintic activity to the human pathogenic hookworm Ancylostoma ceylanicum. This has resulted in the isolation of three previously undescribed isoflavonoid metabolites, denoted parryans A-C, a chalcone, six pterocarpans, and three known compounds from the roots of D. parryi. Parryans A and B express a rarely-seen O-prenyl substituent. Structures of the previously undescribed compounds were established using 1D and 2D NMR spectroscopy and mass spectrometry. The relative and absolute configurations of the undescribed stereoisomers were assigned using chemical shift and coupling constant data and comparisons of specific rotations to published data. The most active of the isolated compounds only expressed a 17% reduction in survival of A. ceylanicum adult hookworm in an ex vivo assay at 50 μg/mL after 5 days exposure. Toxicity, ranging from 47 to 93% reduction in survival of mammalian splenocytes was expressed by four of the compounds.

Chemical Constituents of Stems and Leaves of Tagetespatula L. and Its Fingerprint

Tagetespatula L. is a widely cultivated herbal medicinal plant in China and other countries. In this study, two new 2, 3-dihydrobenzofuran glucosides (1, 2) and fourteen known metabolites (3–16) were isolated from the stems and leaves of T. patula (SLT). The chemical structures of the isolated compounds were characterized comprehensively based on one- and two-dimensional NMR spectroscopy and high resolution mass spectrometry. Absolute configurations of compounds 1 and 2 were determined by ECD calculations. Compounds 1 and 2 exhibited moderate in vitro inhibitory activities against human gastric cancer cell lines (AGS) with IC₅₀ values of 41.20 μmol/L and 30.43 μmol/L, respectively. The fingerprint profiles of stems and leaves of T. patula with three color types of flowers (Janie Yellow Bright, Jinmen Orange, Shouyao Red and Yellow color) were established by high-performance liquid chromatography (HPLC). Ten different batches of stems and leaves were examined as follow: Shouyao Red and Yellow color (1, 2, 3), Janie Yellow Bright (4, 5, 6, 7) and Jinmen Orange (8, 9, 10). Twenty-two common peaks were identified with similarity values ranging from 0.910 to 0.977. Meanwhile, the average peak area of SLT in the three types of flowers was different and it was the highest in Janie Yellow Bright.

Therapeutic Aspects of Squill; An Evidence-Based Review

From ancient times, medicinal plants have been usually utilized to treat many disorders, but today, interest in these herbs is again aroused, because of their fewer side effects and low-cost. In traditional medicine, for many diseases, various medicinal herbs have been suggested so far. Drimia maritime, also named squill, is an important medicinal plant for the treatment of many diseases, especially respiratory diseases. In the current evidence-based study, we conducted a review of the general characteristics, ingredients, administration form, and side effects of squill in traditional medicine. For this purpose, traditional Persian medicine literatures and electronic databases were examined including PubMed, Scopus, and Google Scholar. Many compounds are isolated from D.maritima, including scillaren, scillirubroside, scillarenin, and bufadienolide glycosides. Oxymel is the most commonly used form of squill for various diseases, especially respiratory diseases. Besides, squill has been used in the treatment of cardiovascular, digestive, and dermatological disorders, it is also used against various cancer cells for its antioxidant and cytotoxic properties. Moreover, there is relatively reliable evidence of its benefits for bacterial and helminthic infections, rheumatism, edema, gout, abortion induction, healing of wounds and urine induction. It seems that supplementary studies are required to explore the bioactive agents and their effective mechanisms.

Structural diversity and biological activities of phloroglucinol derivatives from Hypericum species

Plants of the genus Hypericum (Hypericaceae) are used in folk medicine all over the world, H. perforatum being the most well-known species. Standardized extracts of this plant are commercially-available to treat mild to moderate depression cases. The present review summarizes the literature published up to 2016 concerning the phloroglucinol derivatives isolated from Hypericum species, together with their structural features and biological activities. These phytochemical studies led to the isolation of 101 prenylated phloroglucinols, chromanes and chromenes, 35 dimeric acylphloroglucinols, 235 polycyclic polyprenylated acylphloroglucinols, 25 simple benzophenones and 33 phloroglucinol-terpene adducts. These compounds show a diverse range of biological activities, such as antimicrobial, cytotoxic, antinociceptive and antidepressant-like effects.

Phytochemical Composition, Hepatoprotective, and Antioxidant Activities of Phyllodium pulchellum (L.) Desv

Phyllodiumpulchellum has been traditionally used as a medicinal herb because of its health-promoting effects, such as its hepatoprotective and antioxidant activities. In the present study, the petroleum ether fraction, ethyl acetate fraction, n-butanol fraction, and aqueous fraction were successively obtained from the ethanol extract of P. pulchellum. Two fractions, ethyl acetate fraction and n-butanol fraction, were found to display hepatoprotective and antioxidant activities. Further chemical investigation of the active fractions led to the isolation of its main constituents, including 11 flavonoids (1⁻11) and 8 indole alkaloids (12⁻19). There were 9 flavonoids (1⁻9) that were obtained from the ethyl acetate fraction, and 2 flavonoids (10 and 11) and 8 alkaloids (12⁻19) from the n-butanol fraction. Compounds 1⁻11 and 16⁻19 were isolated for the first time from P. pulchellum, and 1, 2, 8, 11, and 18 were obtained from the genus Phyllodium initially. Subsequently, the isolated compounds were evaluated for their in vitro hepatoprotective effects on the human normal hepatocyte cell line L-O2 injured by d-galactosamine and radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH). The flavonoids (-)-epigallocatechin (5) and (-)-epicatechin (6) exhibited prominent hepatoprotective activities with higher cell viability values (65.53% and 62.40% at 10 μM·mL^-1, respectively) than the positive control, silymarin (61.85% at 10 μM·mL^-1). In addition, compared with the positive control of vitamin C (IC₅₀: 5.14 μg·mL^-1), (-)-gallocatechin (3) and (-)-epigallocatechin (5) exhibited stronger antioxidant activities with IC₅₀ values of 3.80 and 3.97 μg·mL^-1, respectively. Furthermore, the total flavonoids from P. pulchellum were characterized using a high-performance liquid chromatography-linear ion trap quadrupole-Orbitrap-mass spectrometry (HPLC-LTQ-Orbitrap-MS). In total, 34 flavonoids were tentatively identified, which had not been previously reported from P. pulchellum. In addition, we performed a semi-quantitative analysis of the isolated flavonoids. The contents of compounds 1⁻11 were 3.88, 17.73, 140.35, 41.93, 27.80, 4.34, 0.01, 0.20, 9.67, 795.85, and 5.23 μg·g^-1, respectively. In conclusion, this study revealed that the flavonoids that were isolated from P. pulchellum showed hepatoprotective and antioxidant activities, indicating that, besides alkaloids, the flavonoids should be the potential pharmacodynamic ingredients that are responsible for the hepatoprotective and antioxidant activities of P. pulchellum.

Hyperjaponol H, A New Bioactive Filicinic Acid-Based Meroterpenoid from Hypericum japonicum Thunb. ex Murray

Hyperjaponol H (1), a new filicinic acid-based meroterpenoid, with a 6/6/10 ring system trans-fused by hetero-Diels–Alder cycloaddition between a germacrane sesquiterpenoid and a filicinic acid moiety, was isolated from aerial parts of Hypericum japonicum. The elucidation of its structure and absolute configuration were accomplished by the analyses of extensive spectroscopic data and the comparison of Cotton effects of electron circular dichroism (ECD) with previously reported ones. The bioactivity assay showed that hyperjaponol H exhibited a moderate inhibitory efficacy on lytic Epstein-Barr virus (EBV) DNA replication in B95-8 cells.

Chemical Constituents of the Ethyl Acetate Extract from Diaphragma juglandis Fructus and Their Inhibitory Activity on Nitric Oxide Production In Vitro

Diaphragma juglandis fructus contains various bioactive constituents. Fourteen compounds were isolated from Diaphragma juglandis fructus by preparative high performance liquid chromatography (pre-HPLC) and high-speed counter-current chromatography (HSCCC). Their structures were identified by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). Compounds (+)-dehydrovomifoliol (12), (6R,9R)-9-hydroxymegastigman-4-en-3-one (13) and (6R,9S)-9-hydroxymegastigman-4-en-3-one (14) are found from Juglans regia L. for the first time. Compounds dihydrophaseic acid (2), blumenol B (3) and (4S)-4-hydroxy-1-tetralone (11) are isolated from Diaphragma juglandis fructus for the first time. The anti-inflammatory effects of isolated compounds were evaluated by an in vitro model of lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Compounds gallic acid (1), ethyl gallate (9) and (+)-dehydrovomifoliol (12) exhibited inhibitory activity on the nitric oxide production of RAW 264.7 at a concentration of 25 μM. The result indicated that the combination HSCCC with pre-HPLC is an effective way for compound separation and purification. And Diaphragma juglandis fructus constituents have the potential for the treatment of inflammatory-related diseases.

Two New Bioactive α-Pyrones from Hypericum japonicum

Hypericum japonicum (Guttiferae), a type of annual or perennial herb, has been historically applied to cure infectious hepatitis, acute and chronic hepatitis, gastrointestinal disorder, and internal hemorrhage. In our successive studies on the genus Hypericum, two new α-pyrones termed japopyrones A and B (1 and 2) were isolated from H. japonicum. Their structures and absolute configurations were established by the comprehensive analyses of spectroscopic data, the application of the Single-crystal X-ray diffraction structural analysis, and the experimental electronic circular dichroism (ECD) spectra. Bioactivity screenings suggested that compound 2 possessed the potential inhibition efficacy on lytic replication of Kaposi’s sarcoma associated herpesvirus (KSHV) with an IC₅₀ 29.46 μM and a selective index of higher than 6.79, respectively.

Two novel prenylated kaempferol derivatives from fresh bud's fur of Platanus acerifolia and their anti-proliferative activities

Two novel prenylated kaempferol derivatives (1, 2), together with seven known metabolites were isolated from ethanol extract of fresh Platanus acerifolia bud's fur by multistep chromatographic processing. Structure of compounds 1 and 2 was confirmed by 1D, 2D NMR spectra and HR-ESI-MS. In addition, compound 1 was further analysed by X-ray crystallography. Anti-proliferative activities in vitro against human breast carcinoma (MCF-7) and human hepatocellular carcinoma (Hep-G2) cell lines for compound 1, 2 and 8 were evaluated. Compound 1 exhibited cytotoxic activity towards MCF-7 and Hep-G2 cell lines with the IC₅₀ values 38.2 and 39.5 μM, respectively. Moreover, compound 2 showed weak cytotoxic activities against the two cell lines.

Phenolic Derivatives from Hypericum japonicum

Three new acylphloroglucinol glycosides, hypericumols A - C, together with fifteen known phenolic derivatives, were isolated from the total phenolic extract of Hypericum japonicum. Hypericumols A, B, and C were characterized as 4,6-dimethyl-2-methylpropanoylphloroglucinol-1- O-β-D-glucopyranoside (1), 4-methyl-2-methylpropanoylphloroglucinol-1- O-β-D-glucopyranoside (2), and (2′ S)-4,6-dimethyl-2-methylbutyrylphloroglucinol-1- O-β-D-glucopyranoside (3), respectively, on the basis of spectroscopic data interpretation and chemical degradation reaction.

Simultaneous determination and pharmacokinetic study of eight components in rat plasma by UHPLC-MS/MS after oral administration of Hypericum japonicum Thunb extract

A rapid and sensitive assay based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was established and validated for the simultaneous determination of gallic acid, protocatechuic acid, vanillic acid, caffeic acid, epicatechin, isoquercitrin, vincetoxicoside B and quercetin in rat plasma using catechin and daidzein as the internal standards (IS). Plasma samples added internal standards were acidified with formic acid then pretreated by direct protein precipitation with acetonitrile. The separation of eight constituents was achieved on a C18 column with gradient elution using methanol and 0.2% acetic acid aqueous solution as the mobile phase and detected by multiple reaction monitoring using electrospray ionization source in the positive-negative ionization mode. The method was validated for sufficient specificity, precision, accuracy, and sensitivity over the concentration range of 10-6000 ng mL(-1) for gallic acid, 1.5-3000 ng mL(-1) for protocatechuic acid, 10-15000 ng mL(-1) for vanillic acid, 2-3600 ng mL(-1) for caffeic acid, 1.5-3600 ng mL(-1) for epicatechin, 4-6000 ng mL(-1) for isoquercitrin, 2-9000 ng mL(-1) for vincetoxicoside B, and 20-18000 ng mL(-1) for quercetin. The overall intra‑run precision and the inter‑run precision were showed in the range of 1.0-14.2% and 2.8-12.9%, respectively, and the accuracy was no more than 12.8%. This analytical method was successfully applied to investigate the pharmacokinetics of eight ingredients in rats after oral administration of Hypericum japonicum Thunb extract.

Flavonol dimers from callus cultures of Dysosma versipellis and their in vitro neuraminidase inhibitory activities

A chemical investigation of callus cultures of Dysosma versipellis led to the isolation of five new flavonol dimers, dysoverines A-E (1-5), together with 12 known compounds (6-17). The structures of new compounds were determined by the extensive spectroscopic data analyses. The biosynthetic pathway of the new compounds was proposed to involve O-methylation, prenylation, and Diels-Alder cycloaddition, which successively occurred in cultured plant cells. Compounds 1-17 exhibited in vitro neuraminidase inhibitory activities with the IC50 values of 31.0-93.9μM.

Jacarelhyperol A induced apoptosis in leukaemia cancer cell through inhibition the activity of Bcl-2 proteins

Background

Hypericum japonicum Thunb. ex Murray is widely used as an herbal medicine for the treatment of hepatitis and tumours in China. However, the molecular mechanisms of its effects are unclear. Our previous research showed that extracts of H. japonicum can induce apoptosis in leukaemia cells. We also previously systematically analysed and isolated the chemical composition of H. japonicum.

Methods

The fluorescence polarisation experiment was used to screen for inhibitors of Bcl-2 proteins which are proved as key proteins in apoptosis. The binding mode was modelled by molecular docking. We investigated the proliferation attenuating and apoptosis inducing effects of active compound on cancer cells by MTT assay and flow cytometry analysis. Activation of caspases were tested by Western blot. A broad-spectrum caspase inhibitor Z-VAD-FMK was used to investigate the caspases-dependence. In addition, co-immunoprecipitation was performed to analyse the inhibition of heterodimerization between anti-apoptotic Bcl-2 proteins with pro-apoptotic proteins. Moreover, in vivo activity was tested in a mouse xenograph tumour model.

Result

Jacarelhyperol A (Jac-A), a characteristic constituent of H. japonicum, was identified as a potential Bcl-2 inhibitor. Jac-A showed binding affinities to Bcl-x_L, Bcl-2, and Mcl-1 with K_i values of 0.46 μM, 0.43 μM, and 1.69 μM, respectively. This is consistent with computational modelling results, which show that Jac-A presents a favorable binding mode with Bcl-x_L in the BH3-binding pocket. In addition, Jac-A showed potential growth inhibitory activity in leukaemia cells with IC₅₀ values from 1.52 to 6.92 μM and significantly induced apoptosis of K562 cells by promoting release of cytochrome c and activating the caspases. Jac-A also been proved that its effect is partly caspases-dependent and can disrupt the heterodimerization between anti-apoptotic Bcl-2 proteins with pro-apoptotic proteins. Moreover, Jac-A dose-dependently inhibited human K562 cell growth in a mouse xenograph tumour model with low toxicity.

Conclusion

In this study, a characteristic constituent of H. japonicum, Jac-A, was shown to induce apoptosis in leukaemia cells by mediating the Bcl-2 proteins. Therefore, we propose a new lead compound for cancer therapy with a low toxicity, and have provided evidence for using H. japonicum as an anti-cancer herb.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-689) contains supplementary material, which is available to authorized users.

Hypericum japonicum Thunb. ex Murray: phytochemistry, pharmacology, quality control and pharmacokinetics of an important herbal medicine

Hypericum japonicum Thunb. ex Murray is mainly distributed throughout Asia, Oceania and North America and is used as an important herbal medicine. H. japonicum contains many valuable secondary metabolites, such as flavonoids, phloroglucinols and xanthones and has hepatoprotective, anti-tumor, antibacterial, antiviral, and antioxidant activities and effects on the cardiovascular system and immunity. Coupled with phytochemical and pharmacological research, a series of analytical methods have been developed to evaluate the quality of H. japonicum based on its bioactive components. A pharmacokinetics study involved the absorption of two main flavonoids of H. japonicum in rats. This review aims to present an up-to-date and comprehensive overview of the phytochemistry, pharmacology, quality control and pharmacokinetics of H. japonicum, which should be useful for the greater development of H. japonicum, especially in the development of new drugs and therapeutics for various diseases.

Urgineaglyceride A: a new monoacylglycerol from the Egyptian Drimia maritima bulbs

One new compound, (2S)-1-O-(Z)-tetracos-6-enoate glycerol (1) named urgineaglyceride A, along with six known compounds, 3,5,7,3',5'-pentahydroxydihydroflavonol (2), stigmasterol (3), (25S)-5β-furostane-3β-22α-26-triol (4), scillaridin A (5), (2S)-(+)-2-hydroxynaringenin-4'-O-β-D-glucopyranoside (6) and quercetin-3'-O-β-D-glucopyranoside (7), were isolated from the EtOAc fraction of Drimia maritima (L.) Stearn bulbs. Their structures were secured based on their IR, UV, 1D and 2D NMR data, in addition to HR-MS data and comparison with the literature data. The isolated compounds were evaluated for their in vitro growth inhibitory activity against A549 non-small cell lung cancer (NSCLC), U373 glioblastoma (GBM) and PC-3 prostate cancer cell lines. Compounds 2 and 3 displayed variable activities against the tested cancer cell lines. Compound 2 was a selective inhibitor of the NSCLC cell line with an IC₅₀ of 2.3 μM, whereas 3 was selective against GBM with IC₅₀ of 0.5 μM and against PC-3 with 2.0 μM.

Inhibitory effects of the constituents of Hippophae rhamnoides on 3T3-L1 cell differentiation and nitric oxide production in RAW264.7 cells

Three new flavonol glycosides, hippophaeosides A-C (1-3), together with 27 known constituents, were isolated from Hippophae rhamnoides L. leaves. Their structures were determined by spectroscopic analyses. Their inhibitory activities on 3T3-L1 preadipocyte differentiation and triglyceride accumulation in maturing adipocytes, and nitric oxide production in RAW264.7 cells were examined.

The effect-enhancing and toxicity-reducing activity of Hypericum japonicum Thunb. extract in murine liver cancer chemotherapy

Chinese herbs are potential sources of antitumor drugs with immunoregulatory activity and few adverse effects. In the present study, we investigated whether the Hypericum japonicum Thunb. (HJT) extract enhanced the efficacy of 5-fluorouracil (5-FU) treatment in murine liver tumor xenografts and reduced toxicity of chemotherapy in hepatoma H22-bearing mice. Tumor weight and inhibition rate, thymus and spleen indices, as well as white blood cell (WBC) count were calculated. The phagocytic function of macrophages was assessed by observing peritoneal macrophages phagocytized chicken red blood cells (RBC). Body weight and toxic reactions of the chemotherapeutic and life prolongation rate were investigated in the mice. Results demonstrated that the HJT extract significantly enhanced the tumor inhibition rate of 5-FU, improved the immune function, reduced the toxic effects and prolonged the survival time in the tumor-bearing mice. Taken together, these results indicated that the HJT extract has a synergistic tumor-inhibiting effect with 5-FU, is able to reduce the toxic side effects and is likely to be safe and efficacious for use in antitumor therapy.

A new auronol from Cudrania cochinchinensis

A new auronol, cudrauronol (1), was isolated from the roots of Cudrania cochinchinensis along with 10 known compounds, 1,3,5-trihydroxy-4-prenylxanthone (2), 1,3,7-trihydroxy-4-prenylxanthone (3), 3,4',5,7-tetrahydroxydihydroflavonol (4), kaempferol (5), 3,6-dihydroxy-1,5-dimethoxyxanthone (6), 2',4',5,7-tetrahydroxyflavanolol (7), 3,7-dihydroxy-1-methoxyxanthone (8), 1,3,5-trihydroxyxanthone (9), cudraflavone B (10), and 2'-oxyresveratrol (11). Compounds 1-8 were evaluated for anti-inflammatory activity on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages. Compounds 2-5 were more active than aminoguanidine, with IC(50) values of 8.8, 23.2, 27.1, and 11.9 μM, respectively.

Caucasicosides E-M, furostanol glycosides from Helleborus caucasicus

Nine furostanol glycosides, namely caucasicosides E-M, were isolated from the MeOH extract of the leaves of Helleborus caucasicus, along with 11 known compounds including nine furostanol glycosides, a bufadienolide and an ecdysteroid. Their structures were established by the extensive use of 1D and 2D NMR experiments along with ESIMS(n) analyses. The steroidal composition of leaves of H. caucasicus shows as particular feature the occurrence of steroidal compounds belonging to the 5β series, unusual for Helleborus species, and in particular, caucasicosides F-H are based on a 5β-polyhydroxylated steroidal aglycon never reported before.

Steroidal glycosides from Ruscus ponticus

A comparative metabolite profiling of the underground parts and leaves of Ruscus ponticus was obtained by an HPLC-ESIMS(n) method, based on high-performance liquid chromatography coupled to electrospray positive ionization multistage ion trap mass spectrometry. The careful study of HPLC-ESIMS(n) fragmentation pattern of each chromatographic peak, in particular the identification of diagnostic product ions, allowed us to get a rapid screening of saponins belonging to different classes, such as dehydrated/or not furostanol, spirostanol and pregnane glycosides, and to promptly highlight similarities and differences between the two plant parts. This approach, followed by isolation and structure elucidation by 1D- and 2D-NMR experiments, led to the identification of eleven saponins from the underground parts, of which two dehydrated furostanol glycosides and one new vespertilin derivative, and nine saponins from R. ponticus leaves, never reported previously. The achieved results highlighted a clean prevalence of furostanol glycoside derivatives in R. ponticus leaves rather in the underground parts of the plant, which showed a wider structure variety. In particular, the occurrence of dehydrated furostanol derivatives, for the first time isolated from a Ruscus species, is an unusual finding which makes unique the saponins profile of R. ponticus.

Flavonoids from eight tropical plant species that inhibit the multidrug resistance transporter ABCG2

Overexpression of ABCG2, a membrane-bound multi-drug transporter, can make tumor cells resistant to treatment with conventional chemotherapeutic agents. A high-throughput screening effort with the NCI repository of natural product extracts revealed that eight tropical plant extracts significantly inhibited the function of ABCG2. This activity was tracked throughout the extract fractionation process to a series of ABCG2 inhibitory flavonoids (1-13). Their structures were identified by a combination of NMR, mass spectrometry, and circular dichroism studies, and this resulted in the elucidation of (2S)-5,7,3'-trihydroxy-4'-methoxy-8-(3''-methylbut-2''-enyl)-flavonone (1), (2S)-5,7,3',5'-tetrahydroxy-8-[3'',8''-dimethylocta-2''(E),7''-dienyl]flavonone (3), and 5,7,3'-trihydroxy-3,5'-dimethoxy-2'-(3'-methylbut-2-enyl)flavone (12) as new compounds.

Steroidal saponins from Yucca gloriosa L. rhizomes: LC-MS profiling, isolation and quantitative determination

The occurrence of steroidal saponins in the rhizomes of Yucca gloriosa has been detected by LC-MS. On the basis of the LC-MS analysis, five steroidal glycosides, including three spirostane, one furostane and one cholestane glycosides, along with seven known compounds have been isolated and characterized by ESI-MS and by the extensive use of 1D- and 2D-NMR experiments. Quantitative analysis of the steroidal glycosides in Y. gloriosa rhizomes was performed by an LC-MS method validated according to European Medicines Agency (EMEA) guidelines. The dried BuOH extract obtained from rhizomes contains more than 25% w/w of glycosides, thus Y. gloriosa rhizomes can be considered a rich source of steroidal glycosides.

Antioxidant Effects of Secondary Metabolites from Geranium psilostemon

An investigation was made of the effects on endogenous antioxidant enzyme activities and H2O2-induced lipid peroxidation inhibition in human red blood cells of the crude MeOH extract and its EtOAc, n-BuOH, and H2O sub-extracts obtained from aerial parts of Geranium psilostemon Ledeb., as well as compounds isolated from the most active EtOAc extract. Gallic acid (1), methyl gallate (2), pusilagin (3), 1,3,6-tri- O-galloyl-β-glucopyranoside (4), 1,2,3,4,6-penta- O-galloyl-β-glucopyranoside (5), kaempferol (6), quercetin (7), kaempferol 7- O-α-rhamnopyranoside (8), and quercetin 7- O-α-rhamnopyranoside (9) were isolated from the aerial parts of the title plant, and their structures identified from spectroscopic (UV, 1D- and 2D- NMR) and spectrometric (TOF-MS) data. All extracts and isolated compounds inhibited H2O2-induced lipid peroxidation and also enhanced the activity of superoxide dismutase (SOD) and catalase (CAT).