Time filter

Source Type

Doylestown, PA, United States

Clement J.A.,Natural Products Discovery Institute | Clement J.A.,Western Carolina University | Clement E.S.H.,Western Carolina University
Current Topics in Medicinal Chemistry | Year: 2014

The genus Aralia contains many plants used medicinally in Asia and the Americas. Although many members of this genus are used medicinally, the vast majority of this genus has not been explored chemically. The species of Aralia that have been explored chemically have yielded compounds of several classes, including triterpenoid saponins, sterols, diterpenoids, and acetylenic lipids. Many of the biologically active components found in genus Aralia have been evaluated for their potential as lead compounds for drug discovery. This review will explore the medicinal chemistry of compounds reported from genus Aralia, and future prospects for this genus will be considered. © 2014 Bentham Science Publishers.

Kath G.S.,Design To Prototype LLC | Sigmund J.M.,Natural Products Discovery Institute | Masurekar P.,Rutgers University
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2012

Despite the availability of many culturebased antibiotic screening methods, the lack of sensitive automated methods to identify functional molecules directly from microbial cells still limits the search for new biologically active compounds. The effectiveness of antibiotic detection is influenced by the solubility of the assayed compounds, indicator strain sensitivity, culture media and assay configuration. We describe a qualitative high throughput screening system for detecting cell-perturbing molecules from bacterial colonies employing two opposed agar layers sequentially formed in prototype Society for Biomolecular Screening (SBS) plates, named Janus plates. Direct assay of microbial colonies against target organisms in opposed agar layers overcomes some of the limitations of agar overlay methods. The system enables the rapid detection of extracellular cell-perturbing molecules, e.g., antibiotics, excreted directly from environmental isolates. The source bacterial colonies remain separate from the target organism. The growth layer is prepared and grown independently, so environmental strains can be grown for longer intervals, at temperatures and in media that favor their growth and metabolite expression, while the assay layer with pathogens, usually requiring nutrient-rich medium and elevated temperatures, are added later. Colonies to be tested can be precisely arrayed on the first agar surface, thus avoiding dispersion and disturbance of potential antibiotic-producing colonies by overlaying agar with the target strain. The rectangular SBS configuration facilitates factorial replication of dense microbial colony arrays for testing with multiple assays and assay conditions employing robotic colony pickers and pin tools. Opposed agar layers only slightly reduced the effectiveness for detecting growth inhibition from pure antibiotics compared to single-layer agar diffusion assays. The Janus plate enabled an automation-Assisted workflow where a lone operator can effectively identify and accumulate bioactive soil bacterial strains within a few weeks. We also envisage the method's utility for functional prescreening colonies of clones from genomic and metagenomic libraries or improved strains originating from mutagenized cells. © The Author(s) 2012.

Su Q.,Virginia Polytechnic Institute and State University | Krai P.,Virginia Polytechnic Institute and State University | Goetz M.,Natural Products Discovery Institute | Cassera M.B.,Virginia Polytechnic Institute and State University | Kingston D.G.I.,Virginia Polytechnic Institute and State University
Planta Medica | Year: 2015

Bioassay-guided fractionation of an EtOH extract of the roots of the plant Apoplanesia paniculata (Fabaceae) led to the isolation of the three known compounds amorphaquinone (1), pendulone (2), and melilotocarpan C (3), and the two new pterocarpans 4 and 5. Compounds 1 and 2 exhibited good antiplasmodial activity with IC50 values of 5.7±1.5 and 7.0±0.8μM, respectively. Compound 3 exhibited weak antiplasmodial activity (41.8±5.2μM), while compounds 4 and 5 were inactive. Compound 6 was synthesized to confirm the structure of 5, and it showed enhanced antiplasmodial activity (15.8±1.4μM) compared to its analogues 3-5. © Georg Thieme Verlag KG Stuttgart · New York.

Liu Y.,Virginia Polytechnic Institute and State University | Rakotondraibe L.H.,Virginia Polytechnic Institute and State University | Rakotondraibe L.H.,Ohio State University | Brodie P.J.,Virginia Polytechnic Institute and State University | And 4 more authors.
Natural Product Communications | Year: 2014

Bioassay-directed fractionation of an antiproliferative ethanol extract of the leaves and twigs of Piptocoma antillana (Asteraceae) afforded two new goyazensolide-type sesquiterpene lactones named 5-O-methyl-5-epiisogoyazensolide (1) and 15-O-methylgoyazensolide (2), together with the known compounds 1-oxo-3,10-epoxy-8-(2-methylacryloxy)-15-acetoxygermacra-2,4,11(13)-trien-6(12)-olide (3) and 5-epiisogoyazensolide (4). The structure elucidation of all compounds was carried out based on NMR and mass spectroscopic data analyses. The relative and absolute configurations of all the isolated compounds were determined from their CD and NOESY NMR spectra. Compounds 1-4 showed moderately potent antiproliferative activities against A2780 ovarian cancer cells, with IC50 values of 1.5±0.5, 0.6±0.3, 1.62±0.05, and 1.56±0.04 μM, respectively. They also displayed antimalarial activity against Plasmodium falciparum, with IC50 values of 6.2± 0.5, 2.2 ± 0.5, 8.0 ± 0.4, and 9.0±0.6 μM, respectively.

Ren Y.,Ohio State University | Yuan C.,Ohio State University | Qian Y.,Ohio University | Chai H.-B.,Ohio State University | And 3 more authors.
Journal of Natural Products | Year: 2014

A new alkylated chalcone (1), a new 1,16-hexadecanediol diester (2), and eight known compounds were isolated from a dichloromethane-soluble repository extract of the leaves and twigs of Cryptocarya rubra collected in Hawaii. The structures of the new compounds were determined by interpretation of their spectroscopic data, and the absolute configurations of the two known cryptocaryanone-type flavonoid dimers, (+)-bicaryanone A (3) and (+)-chalcocaryanone C (4), were ascertained by analysis of their electronic circular dichroism and NOESY NMR spectra. All compounds isolated were evaluated against HT-29 human colon cancer cells, and, of these, (+)-cryptocaryone (5) was found to be potently cytotoxic toward this cancer cell line, with an IC 50 value of 0.32 μM. This compound also exhibited glucose transport inhibitory activity when tested in a glucose uptake assay. © 2013 The American Chemical Society and American Society of Pharmacognosy.

Discover hidden collaborations