Atractylodes macrocephala Rhizomes Contain Anti-inflammatory Sesquiterpenes.

Two new compounds, named eudesm-4(15),7-diene-3α,9ß,11-triol (1) and eudesm-4(15),7-diene-1ß,3α,9ß,11-tetraol (2) together with three known sesquiterpene lactones (1S,5R,7R,10R)-secoatractylolactone (3), (1S,5R,7R,10R)-secoatractylolactone-11-O-ß-D-glucopyranoside (4) atractylenolide III (5) were isolated from the rhizomes of Atractylodes macrocephala. Their structures were elucidated by using one-dimensional (1D) and 2D-NMR spectra and high resolution electrospray ionization (HR-ESI)-MS data. Compound 5 exhibited the most active anti-inflammatory activity with IC50 values of 27.5 µM in inhibiting of nitric oxide production. Compounds 1, 2, and 3 showed moderate effects while compound 4 was inactive.

Essential Oils from Vietnamese Asteraceae for Environmentally Friendly Control of Aedes Mosquitoes.

Mosquitoes, in addition to being a biting nuisance, are vectors of several pathogenic viruses and parasites. As a continuation of our work identifying abundant and/or invasive plant species in Vietnam for use as ecologically friendly pesticidal agents, we obtained the essential oils of Blumea lacera, Blumea sinuata, Emilia sonchifolia, Parthenium hysterophorus, and Sphaeranthus africanus; analyzed the essential oils using gas chromatographic techniques; and screened the essential oils for mosquito larvicidal activity against Aedes aegypti and Aedes albopictus. The most active larvicidal essential oils were B. sinuata, which was rich in thymohydroquinone dimethyl ether (29.4%), (E)-ß-caryophyllene (19.7%), α-pinene (8.8%), germacrene D (7.8%), and α-humulene (4.3%), (24-h LC50 23.4 and 29.1 µg/mL) on Ae. aegypti and Ae. albopictus, respectively, and Emilia sonchifolia, dominated by 1-undecene (41.9%) and germacrene D (11.0%), (24-h LC50 30.1 and 29.6 µg/mL) on the two mosquito species. The essential oils of P. hysterophorus and S. africanus were also active against mosquito larvae. Notably, B. sinuata, P. hysterophorus, and S. africanus essential oils were not toxic to the non-target water bug, Diplonychus rusticus. However, E. sonchifolia essential oil showed insecticidal activity (24-h LC50 48.1 µg/mL) on D. rusticus. Based on these results, B. sinuata, P. hysterophorus, and S. africanus essential oils appear promising for further investigations.

Essential Oil Compositions of Three Invasive Conyza Species Collected in Vietnam and Their Larvicidal Activities against Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus.

Mosquito-borne infectious diseases are a persistent problem in tropical regions of the world, including Southeast Asia. Vector control has relied principally on synthetic insecticides, but these have detrimental environmental effects and there is an increasing demand for plant-based agents to control insect pests. Invasive weedy plant species may be able to serve as readily available sources of essential oils, some of which may be useful as larvicidal agents for control of mosquito populations. We hypothesize that members of the genus Conyza (Asteraceae) may produce essential oils that may have mosquito larvicidal properties. The essential oils from the aerial parts of Conyza bonariensis, C. canadensis, and C. sumatrensis were obtained by hydrodistillation, analyzed by gas chromatography-mass spectrometry, and screened for mosquito larvicidal activity against Aedes aegypti, Ae. albopictus and Culex quinquefasciatus. The essential oils of C. canadensis and C. sumatrensis, both rich in limonene (41.5% and 25.5%, respectively), showed notable larvicidal activities against Ae. aegypti (24-h LC50 = 9.80 and 21.7 µg/mL, respectively) and Ae. albopictus (24-h LC50 = 18.0 and 19.1 µg/mL, respectively). These two Conyza species may, therefore, serve as sources for alternative, environmentally-benign larvicidal control agents.

Antioxidant, Xanthine Oxidase, α-Amylase and α-Glucosidase Inhibitory Activities of Bioactive Compounds from Rumex crispus L. Root.

The root of Rumex crispus L. has been shown to possess anti-gout and anti-diabetic properties, but the compounds responsible for these pharmaceutical effects have not yet been reported. In this study, we aimed to isolate and purify active components from the root of R. crispus, and to evaluate their anti-radical, anti-gout and anti-diabetic capacities. From the ethyl acetate (EtOAc) extract, two compounds, chrysophanol (1) and physcion (2), were isolated by column chromatography with an elution of hexane and EtOAc at a 9:1 ratio. Their structures were identified by spectrometric techniques including gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), X-ray diffraction analyses and nuclear magnetic resonance (NMR). The results of bioassays indicated that (1) showed stronger activities than (2). For antioxidant activity, (1) and (2) exhibited remarkable DPPH radical scavenging capacity (IC50 = 9.8 and 12.1 µg/mL), which was about two times stronger than BHT (IC50 = 19.4 µg/mL). The anti-gout property of (1) and (2) were comparable to the positive control allopurinol, these compounds exerted strong inhibition against the activity of xanthine oxidase (IC50 = 36.4 and 45.0 µg/mL, respectively). In the anti-diabetic assay, (1) and (2) displayed considerable inhibitory ability on α-glucosidase, their IC50 values (IC50 = 20.1 and 18.9 µg/mL, respectively) were higher than that of standard acarbose (IC50 = 143.4 µg/mL). Findings of this study highlight that (1) and (2) may be promising agents to treat gout and diabetes, which may greatly contribute to the medicinal properties of Rumex crispus root.

Undescribed chalcone and stilbene constituents from Lysimachia baviensis and their anti-inflammatory effect.

The chemical composition and anti-inflammatory activity of the endemic Lysimachia baviensis were investigated for the first time in this study. A phytochemical fractionation of the methanol extract of L. baviensis resulted in the isolation of a new stilbene (bavienside A, 1) and two new chalcone glycosides (baviensides B and C, 2 and 3). Their structures were elucidated via the interpretation of NMR and HRESIMS spectroscopic data. Compounds 1-3 strongly inhibited the production of nitric oxide in LPS-induced RAW264.7 cells with the IC50 values of 6.23, 2.86 and 3.51 µM, respectively. The C-acetylstilbene and carbomethyl chalcone structures in compound 1 and 3 were found for the first time from natural source and could be important markers for chemotaxonomy of Lysimachia baviensis.

Pro-apoptoticeffect of diterpenoids from Fokienia hodginsii on acute myeloid leukemia cells.

Previously, we isolated four known diterpenoids, trans-communic acid (1), 13-oxo-15,16-dinor-labda-8(17), 11E-diene-19-oic acid (2), 3ß-hydroxytotarol (3), and totarolone (4) from Fokienia hodginsii leaves. Further study demonstrated the antiproliferative activity of all four compounds in acute myeloid leukemia (OCI-AML) cells due to impaired cell cycle progression. Interestingly, 3ß-hydroxytotarol (3) had very powerful bioactivity at low concentrations (5 µg/mL).

Anti-proliferative diterpenes from Dacrycarpus imbricatus.

A new diterpene, cassipouryl hexadecanoate (2), in addition to the cassipourol (1) and four terpenes (3-6) were isolated from the twigs and leaves of Dacrycarpus imbricatus (Blume) de Laub. The structures of the two monocyclic diterpenes (1, 2), were elucidated on the basic of 1D and 2D NMR spectroscopic data and compared with the literature. These two monocyclic diterpenes (1, 2) were tested for their anti-proliferative activity on acute myeloid leukemia (OCI-AML) cells. The results showed that 1 had significantly anti-proliferative activity whereas 2 was weakly active.

20-Hydroxyecdysone from Dacrycarpus imbricatus bark inhibits the proliferation of acute myeloid leukemia cells.

OBJECTIVE: To investigate the anti-proliferative effects of 20-hydroxyecdysone isolated from the bark of Dacrycarpus imbricatus (Blume) de Laub. METHODS: Column chromatography was used for isolation of compounds from plant material. The structure of the isolated compound was identified by mass spectrometry and nuclear magnetic resonance techniques, including HSQC, HMBC, NOE-difference experiments. The isolated compound was tested for its anti-proliferative activity in acute myeloid leukemia (AML) and OCI-AML cells. RESULTS: Compound 1 was isolated from the ethyl acetate fraction of Dacrycarpus imbricatus barks by column chromatography. Its chemical structure was identified as 20-hydroxyecdysone (20HE), a cholestane-type ecdysteroid, by a combination of mass spectrometry and nuclear magnetic resonance spectrometric analyses. Our goal was to test the anti-proliferative activity of 20HE using the OCI-AML cell line. 20HE significantly decreased OCI cell number at a concentration of 1 mg/mL, whereas lower concentrations were ineffective. Moreover, this decrease was due to partial blockage of the G1/S phase of the cell cycle, with a reduction of cells in the G2M phase, not due to increased apoptosis. CONCLUSIONS: This indicates that 20HE significantly decreases the number of cells in the G1/S phase of the cell cycle in human AML cells. This is the first time that the anti-proliferative activity of 20HE against a human tumor cell line has been reported.