Search results for "lignans"
showing 10 items of 24 documents
Oxidative burst inhibitory and cytotoxic amides and lignans from the stem bark of Fagara heitzii (Rutaceae)
2009
Two amides, heitziamide A and heitziamide B and two phenylethanoids, heitziethanoid A and heitziethanoid B together with thirteen known compounds were isolated from F. heitzii (Letouzey). The structures of all compounds were established by spectroscopic analysis. Nine compounds were evaluated for oxidative burst inhibitory activity in a chemoluminescence assay and for cytotoxicity against PC-3 prostate cancer cells. All compounds exhibited a clear suppressive effect on phagocytosis response upon activation with serum opsonized zymosan at the range of IC50 = 2.0-6.5 mu M, but no cytotoxic effect was observed (IC50 > 100 mu M). (C) 2009 Elsevier Ltd. All rights reserved.
Dietary Polyphenol Intake is Associated with HDL-Cholesterol and A Better Profile of other Components of the Metabolic Syndrome: A PREDIMED-Plus Sub-…
2020
Dietary polyphenol intake is associated with improvement of metabolic disturbances. The aims of the present study are to describe dietary polyphenol intake in a population with metabolic syndrome (MetS) and to examine the association between polyphenol intake and the components of MetS. This cross-sectional analysis involved 6633 men and women included in the PREDIMED (PREvenció
Inverse association between habitual polyphenol intake and incidence of cardiovascular events in the PREDIMED study
2014
Background and aims: Epidemiologic and biological evidence supports an inverse association between polyphenol consumption and the risk of cardiovascular disease (CVD). However, no previous studies have prospectively evaluated the relationship between polyphenol intake and the incidence of CVD in such a comprehensive way. The aim was to evaluate the association between intakes of total polyphenol and polyphenol subgroups, and the risk of major cardiovascular events (myocardial infarction, stroke or death from cardiovascular causes) in the PREDIMED study. Methods and results: The present work is an observational study within the PREDIMED trial. Over an average of 4.3 years of follow-up, there…
Polyphenol intake and mortality risk: a re-analysis of the PREDIMED trial
2014
[Background] Polyphenols may lower the risk of cardiovascular disease (CVD) and other chronic diseases due to their antioxidant and anti-inflammatory properties, as well as their beneficial effects on blood pressure, lipids and insulin resistance. However, no previous epidemiological studies have evaluated the relationship between the intake of total polyphenols intake and polyphenol subclasses with overall mortality. Our aim was to evaluate whether polyphenol intake is associated with all-cause mortality in subjects at high cardiovascular risk.
Novel Domino Oxidative Coupling: C−C Bond Formation Sequence to Highly Functionalized Dibenzo[a,c]cycloheptenes
2011
A domino sequence involving various MoCl(5)-mediated oxidations followed by trapping and supposed [3,3]-sigmatropic rearrangement provides a fast access to the full carbon skeleton of metasequirin-B. A variety of different moieties R(1) and R(2) are tolerated.
Cytotoxic Compounds from the Fruits of Uapaca togoensis towards Multifactorial Drug-Resistant Cancer Cells
2014
Cancer cells may rapidly acquire multidrug resistance, mainly due to the presence of adenosine triphosphate-binding cassette transporters, epidermal growth factor receptor, or mutations in the p53 tumor suppressor gene. This work was designed to assess the cytotoxicity of the methanol crude extracts and compounds from the fruits of Uapaca togoensis, namely, β-amyryl acetate (1), 11-oxo-α-amyryl acetate (2), lupeol (3), pomolic acid (4), futokadsurin B (5), arborinin (6), and 3-O-β-D-glucopyranosyl sitosterol (7) against nine drug sensitive and multidrug-resistant cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of the fruits of U. togoensis and compound…
Phytotoxic Lignans from Artemisia arborescens
2018
A systematic bioassay-guided fractionation of methylene chloride extracts of the aerial part of Artemisia arborescens was performed in order to identify its phytotoxic compounds Two lignans were isolated, sesamin and ashantin, that inhibited growth of Agrostis stolonifera (bentgrass), a monocot, and Lactuca sativa (lettuce), a dicot, at 1 mg mL–1. In a dose-response screening of these lignans for growth inhibition against Lemna paucicostata (duckweed), ashantin was the most active with an IC50 of ca. 224 μM. The mode of action of these compounds is still unknown. In mosquito larvicidal bioassays the pure compounds sesamin and ashantin did not cause mortality at the highest dose of 125 mg/L…
Bioactivity of fractions and constituents of Piper capense fruits towards a broad panel of cancer cells.
2020
Abstract Ethnopharmacological relevance Piper capense is a medicinal spice whose fruits are traditionally used as aqueous decoction to heal several ailments such as trypanosomiasis, helminthic infections, and cancer. Aim of the study. (1) To perform phytochemical investigation of the methanol extract of Piper capense; (2) to evaluate the cytotoxicity of botanicals (PCF, fractions PCFa-e), isolated phytochemicals on a broad panel of animal and human cancer cell lines; (3) to evaluate the induction of apoptosis of the most active samples. Material and methods Resazurin reduction assay (RRA) was used to determine the cytotoxicity of the studied samples. Cell cycle distribution (PI staining), a…
Oxygen-assisted hydroxymatairesinol dehydrogenation: a selective secondary-alcohol oxidation over a gold catalyst.
2013
Selective dehydrogenation of the biomass-derived lignan hydroxymatairesinol (HMR) to oxomatairesinol (oxoMAT) was studied over an Au/Al(2)O(3) catalyst. The reaction was carried out in a semi-batch glass reactor at 343 K under two different gas atmospheres, namely produced through synthetic air or nitrogen. The studied reaction is, in fact, an example of secondary-alcohol oxidation over an Au catalyst. Thus, the investigated reaction mechanism of HMR oxidative dehydrogenation is useful for the fundamental understanding of other secondary-alcohol dehydrogenation over Au surfaces. To investigate the elementary catalytic steps ruling both oxygen-free- and oxygen-assisted dehydrogenation of HMR…
Phytochemical Profile and Apoptotic Activity of Onopordum cynarocephalum.
2012
A phytochemical investigation of acetone and chloroform extracts of the aerial parts of Onopordum cynarocephalum Boiss. et Blanche was carried out. It led to the isolation of two new sesquiterpenes, the elemane aldehyde (2) and the eudesmane (11), together with 15 known compounds: two lignans (1 and 15) and 13 sesquiterpenes (3–10, 12–14, 16, 17). The structures were elucidated by spectroscopic analyses, especially 1D and 2D NMR spectra. The anti-growth effect against three human melanoma cell lines, M14, A375, and A2058, of the different extracts and compounds of O. cynarocephalum was also investigated. Among them, the chloroform extract exhibited the strongest biological activity, while t…