Constituents of Leaves of Tetradium Glabrifolium

Indole alkaloids from the bark of Acacia confusa and their potential antinociceptive and anti-inflammatory activities

A pair of novel trimeric indole alkaloid enantiomers [(±)-8], five new bisindole alkaloids [4-7 and (±)-9], and three pairs of new monomeric indole alkaloid enantiomers [(±)-1-(±)-3], together with seven known alkaloids (10-16), were isolated from the bark of Acacia confusa. Their structures were determined on the basis of spectroscopic methods, especially by NMR data analyses combined with single-crystal X-ray diffraction and electronic circular dichroism analyses. Compounds 4 and 11-16 exhibited significant antinociceptive activities in an acetic acid-induced writhing test. Compounds (+)-9 and (-)-9 displayed anti-inflammatory activities through the inhibition of the NF-κB pathway, with inhibitory rates of 68.9% and 59.5%, respectively, at a concentration of 10 µM.

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).

Constituents of Aquilaria sinensis Leaves Upregulate the Expression of Matrix Metalloproteases 2 and 9

In this novel study, we isolated 28 compounds from the leaves of Aquilaria sinensis (Lour.) Gilg based on a bioassay-guided procedure and also discovered the possible matrix metalloprotease 2 (MMP-2) and 9 (MMP-9) modulatory effect of pheophorbide A (PA). To evaluate the regulatory activity on MMP-2 and MMP-9, the HT-1080 human fibrosarcoma cells were treated with various concentrations of extracted materials and isolated compounds. PA was extracted by methanol from the leaves of A. sinensis and separated from the fraction of the partitioned ethyl acetate layer. PA is believed to be an active component for MMP expression since it exhibited significant stimulation on MMP-2 and proMMP-9 activity. When treating with 50 μM of PA, the expression of MMP-2 and MMP-9 were increased 1.9-fold and 2.3-fold, respectively. PA also exhibited no cytotoxicity against HT-1080 cells when the cell viability was monitored. Furthermore, no significant MMP activity was observed when five PA analogues were evaluated. This study is the first to demonstrate that C-17 of PA is the deciding factor in determining the bioactivity of the compound. The MMP-2 and proMMP-9 modulatory activity of PA indicate its potential applications for reducing scar formation and comparative medical purposes.

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.

Constituents of the Fruits of Citrus medica L. var. sarcodactylis and the Effect of 6,7-Dimethoxy-coumarin on Superoxide Anion Formation and Elastase Release

Investigation of the chemical constituents from the fruits of Citrus medica L. var. sarcodactylis Swingle has led to the characterization of a new sesquiterpene 1 along with thirty-two known compounds. The structure of 1 was established on the basis of 2D NMR spectroscopic and mass spectrometric analyses, and the known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. In addition, most of the isolated compounds were evaluated for the activity assayed by the in vitro inhibition of superoxide anion generation and elastase release by human neutrophils. The results showed that only 6,7-dimethoxycoumarin (5) exhibited significant inhibition of superoxide anion generation, with IC₅₀ value of 3.8 ± 1.4 μM.

Larvicidal activity of the essential oil from Tetradium glabrifolium fruits and its constituents against Aedes albopictus

BACKGROUND

In our screening programme for new agrochemicals from wild plants, the essential oil of Tetradium glabrifolium (Champ. ex Benth.) T.G. Hartley fruits was found to possess strong larvicidal activity against the Asian tiger mosquito, Aedes albopictus L. The essential oil was extracted via hydrodistillation, and the constituents were determined by GC-MS analysis. The active compounds were isolated and identified by bioassay-directed fractionation.

RESULTS

GC-MS analyses revealed the presence of 19 components with 2-tridecanone (43.38%), 2-undecanone (24.09%), D-limonene (13.01%), caryophyllene (5.04%) and β-elemene (4.07%) being the major constituents. Bioactivity-directed chromatographic separation of the oil led to the isolation of 2-tridecanone, 2-undecanone and D-limonene as active compounds. The essential oil of T. glabrifolium exhibited larvicidal activity against the early fourth-instar larvae of A. albopictus, with an LC50 value of 8.20 µg mL(-1). The isolated constituent compounds, 2-tridecanone, 2-undecanone and D-limonene, possessed strong larvicidal activity against the early fourth-instar larvae of A. albopictus, with LC50 values of 2.86, 9.95 and 41.75 µg mL(-1) respectively.

CONCLUSION

The findings indicated that the essential oil of T. glabrifolium fruits and the three constituents have an excellent potential for use in control of A. albopictus larvae and could be useful in the search for newer, safer and more effective natural compounds as larvicides.

The constituents of roots and stems of Illigera luzonensis and their anti-platelet aggregation effects

Phytochemical investigation of the roots and stems of Illigera luzonensis afforded two new aporphine alkaloids (1) and (2), one new bisdehydroaporphine alkaloid (3), and one new benzenoid (4), along with 28 known structures. The structures of new compounds were elucidated by spectral and MS analysis. Among the isolated compounds, (1) and (4–13) were subjected into the examination for their inhibitory effects on the aggregation of washed rabbit platelets.

Secondary metabolites from the stems of Engelhardia roxburghiana and their antitubercular activities

Bioassay-guided fractionation of stems of Engelhardia roxburghiana led to isolation of: four diarylheptanoids, engelheptanoxides A-D (1-4); two cyclic diarylheptanoids, engelhardiols A (5) and B (6); one naphthoquinone dimer, engelharquinonol (7); and one 1-tetralone, (4S)-4,6-dihydroxy-1-tetralone (8), along with 24 known compounds (9-32). The structures of 1-8 were by spectroscopic analysis. Compounds 5, 6, 13, 22, and 23 showed antitubercular activity against Mycobacterium tuberculosis H(37)Rv with MIC values of 72.7, 62.1, 9.1, 15.3, and 70.1μM, respectively.

Chemical constituents from Lobelia chinensis and their anti-virus and anti-inflammatory bioactivities

In total, forty six compounds, including the novel compound lobechine (1), were characterized from the methanol extracts of Lobelia chinensis. The chemical structures of known metabolites were identified by comparing their spectroscopic and physical data with compounds reported in the literature. The structure of lobechine (1) was comprehensively established with the aid of 1D and 2D NMR spectroscopic analyses. In addition, selected isolates were screened for their inhibition of HSV-1 replication, superoxide anion generation, and elastase release. Among the tested compounds, scoparone (10) exhibited significant inhibition of superoxide anion generation with IC(50) of 6.14 ± 1.97 μM and lobechine (1) exhibited moderate inhibition of elastase release with IC(50) of 25.01 ± 6.95 μM, respectively.

Gastroprotective activities of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) on the growth of the stomach cancer AGS cell line and indomethacin-induced gastric ulcers

Adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) seeds have long been used to treat warts, chapped skin, rheumatism, and neuralgia in traditional Chinese medicine (TCM). Recently, studies demonstrated its anti-inflammatory, antiproliferative, antitumor, and antiallergic activities. In the present study, we first report the gastroprotective effects of dehulled adlay (DA) seeds, which consist of bran (AB) and endosperm (AE). The DA ethanolic extract (DAE) was prepared, along with the AB and AE ethanolic extracts (ABE and AEE), and the inhibitory effects of these extracts were tested on the AGS gastric cancer cell line. Results indicated that the ABE showed better antiproliferative activity, and 19 compounds were purified from AB in a further phenolic-compound-guided separation. Among the isolated compounds, caffeic and chlorogenic acids significantly suppressed the growth of AGS cells. In addition, the antiulcer activity of DA was examined in an indomethacin-induced gastric lesion model. The ulcer index (UI) and oxidative biomarkers in animals decreased, while the non-protein sulfhydryl (NPSH) groups were elevated when given DA. This is the first investigation of antiulcer activity of adlay, and we demonstrated that the antioxidative-active phenolic acids in DA contribute to some portion of the gastroprotective effects.

Anti-inflammatory and antioxidant components from Hygroryza aristata

Twenty-six known compounds and two new compounds, including a new lignan, (7S*,8R*,7’R*,8’S*)-icariol A₂-9-O-β-xylopyranoside (1), and a new indole alkaloid, hygarine (2), were isolated from the extracts of Hygroryza aristata (Gramineae). The structures of all compounds were elucidated on the basis of NMR spectral analysis. The compounds (-)-epigallocatechin-3-O-gallate (4) and (-)-epicatechin-3-O-gallate (5) possess free radical scavenging activities and compound 1 could inhibit superoxide anion generation and elastase release by fMLP/CB-induced human neutrophils with IC50 values of 19.33 ± 0.86 and 24.14 ± 1.59 μM, respectively.

Secondary metabolites from the red mould rice of Monascus purpureus BCRC 38113

One new tetralone, monaspurpurone (1), was isolated from the EtOH extract of a yellow mutant of the fungus Monascus purpureus BCRC 38113 (Eurotiaceae) grown on rice, along with five known compounds, β-sitosteryl palmitate (2), ergosterol (3), ankaflavin (4), monascin (5) and p-nitrophenol (6). They were characterised on the basis of spectral analysis and comparison with literature data. All the isolates were also evaluated for the scavenging properties towards the DPPH in TLC autographic and spectroscopic assays.

Secondary metabolites from the roots of Litsea hypophaea and their antitubercular activity

Bioassay-guided fractionation of the roots of Litsea hypophaea led to the isolation of seven new butanolides, namely, litseakolides H-N (1-7), all with the 3R,4S configuration, as well as three new biarylpropanoids, hypophaone (8), hypophaol (9), and hypophane (10), and 15 known compounds. The structures of 1-10 were determined by means of spectroscopic analysis. Litseakolide L (5) and N-trans-feruloylmethoxytyramine (11) showed antitubercular activity against Mycobacterium tuberculosis strain H(37)Rv, with MIC values of 25 and 1.6 microg/mL, respectively.

Chemical constituents from Abutilon indicum

The investigation on the chemical constituents of the whole plant of Abutilon indicum has resulted in the isolation of two new compounds, abutilin A (1) and (R)-N-(1'-methoxycarbonyl-2'-phenylethyl)-4-hydroxybenzamide (2), as well as 28 known compounds. The structures of the two new compounds were established on the basis of the spectroscopic analysis, and the known compounds were identified by comparison of their spectroscopic and physical data with those reported in the literature.

Chemical constituents of Nouelia insignis Franch

Two new diterpenes and ent-15alpha-hydroxykaur-16-en-19-oic acid 11,12-acetonide (3), together with 23 known compounds were isolated from the dried aerial parts of Nouelia insignis Franch. The structures of new compounds were determined to be ent-14beta,15alpha-dihydroxykaur-16-en-19-oic acid (1), ent-14beta-hydroxy-15-oxokaur-16-en-19-oic acid (2) on the basis of spectral and chemical evidence. The structure of ent-11alpha,16alpha-epoxy-15alpha-hydroxy-16S-kaur-19-oic acid (4) was confirmed by X-ray crystallographic analysis.

Chemical investigation of Phyllanthus reticulatus by HPLC-SPE-NMR and conventional methods

Eight compounds, including two flavonoid glycosides, were isolated from the butanol-soluble fraction of the methanolic extract of the leaves of Phyllanthus reticulatus by conventional methods. A polyphenol rich fraction, obtained by Sephadex LH-20 fractionation, was also studied using an HPLC-SPE-NMR technique leading to the characterization of six compounds including three additional flavonoid glycosides. The latter approach used only 1 mg of samples, theoretically equivalent to 0.3 g of dry leaves. This study demonstrates that HPLC-SPE-NMR is very useful for thorough chemical investigation and also offers the advantages of saving time, plant materials and consumables over more conventional methods.

Constituents from the Leaves of Phellodendron amurense and Their Antioxidant Activity

Three new coumarins, phellodenols F-H (1-3) and a new glutaric acid derivative, phellodendric acid-A (4) were isolated from the leaves of Phellodendron amurense together with twenty-nine known compounds. Extensive 1D and 2D NMR experiments and other spectroscopic studies were employed to determine the structures of 1-4. The isolated compounds were screened for their antioxidant activity through DPPH (alpha,alpha-diphenyl-beta-picrylhydrazyl) radical scavenging assay. Compounds quercetin, quercetin-3-O-beta-D-glucoside, quercetin-3-O-beta-D-galactoside and kaempferol-3-O-beta-D-glucoside demonstrated significant radical scavenging activity comparable to vitamin E.

Constituents of Leaves of Phellodendron japonicum MAXIM. and Their Antioxidant Activity

Three new flavonoid derivatives, 6'''-O-acetyl amurensin (1), 6'''-O-acetyl phellamurin (3) and (2R)-phellodensin-F (5), together with thirty known compounds have been isolated from the leaves of Phellodendron japonicum MAXIM. Their structures were established by means of spectroscopic analysis, including extensive 2D NMR and Mass spectra. The known compounds were identified by comparison with published physical and spectral data. The isolated compounds were screened for their in vitro antioxidant activity through DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. Compounds quercetin and phellodenin-A demonstrated significant radical scavenging activity.

New Neolignans from Spiraea formosana

Phytochemical investigation on the ethanol extract from the stems of Spiraea formosana has resulted in the isolation of four new neolignans, named spiraformin-A, -B, -C and -D (1-4), together with thirty five known compounds. Their structures were established primarily on the basis of 1D and 2D NMR spectral and chemical transformation methods.

Cytotoxic and Anti-HIV Principles from the Rhizomes of Begonia nantoensis

Three new compounds: begonanline (1). nantoamide (2). and methyl (S)-glycerate (3). as well as forty-four known compounds have been isolated and characterized from the rhizomes of Begonia nantoensis. The structures of these compounds were determined by spectral analyses and/or X-ray crystallography. Among them, cucurbitacin B (4). dihydrocucurbitacin B (5). cucurbitacin E (6). dihydrocucurbitacin E (7). cucurbitacin I (8). and (-)-auranamide (9). showed cytotoxicity against four human cancer cell lines. 3beta,22alpha-Dihydroxyolean-12-en-29-oic acid (10), indole-3-carboxylic acid (11), 5,7-dihydroxychromone (12), and (-)-catechin (13) demonstrated significant activity against HIV replication in H9 lymphocyte cells.