Search results for "Helichrysum"
showing 10 items of 17 documents
Tiliroside and gnaphaliin inhibit human low density lipoprotein oxidation.
2004
Two flavonoids, gnaphaliin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation. LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavon…
A new dual inhibitor of arachidonate metabolism isolated from Helichrysum italicum.
2003
Six acetophenones (1-6) and one gamma-pyrone (7), previously isolated from Helichrysum italicum, were tested for their ability to inhibit enzymatic and non-enzymatic lipid peroxidation, the stable 1,1-diphenyl-2-pycryl-hydrazyl free radical, superoxide scavenging and arachidonic acid metabolism. In addition, they were studied in different experimental models such as the chronic inflammation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA), the phospholipase A(2)-induced mouse paw oedema test, the carrageenan-induced mouse paw oedema test, and the writhing induced by acetic acid in the mouse. Of the assayed compounds, only 1 inhibited enzymatic lipid peroxidation but had no effect on no…
Assessment of the anti-inflammatory activity and free radical scavenger activity of tiliroside
2003
Three flavonoids, gnaphaliin, pinocembrin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their antioxidant and/or scavenger properties and in vivo in different models of inflammation. In vitro tests included lipid peroxidation in rat liver microsomes, superoxide radical generation in the xanthine/xanthine oxidase system and the reduction of the stable radical 1,1-diphenyl-2-pycryl-hydrazyl (DPPH). Acute inflammation was induced by application of 12-O-tetradecanoylphorbol 13-acetate (TPA) to the mouse ear or by subcutaneous injection of phospholipase A(2) or serotonin in the mouse paw. Eczema provoked on the mouse ear by repeated administration of TPA was selec…
Anti-inflammatory and antioxidant properties of Helichrysum italicum.
2002
Abstract The anti-inflammatory and antioxidant activities of the aerial part of Helichrysum italicum extracts have been established in various in-vivo and in-vitro experimental models. The results obtained on the acute oedemas induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) and ethyl phenylpropiolate in the mouse ear, by serotonin and phospholipase A2 (PLA2) in the mouse paw, on chronic inflammation induced by repeated application of TPA in the mouse ear and on the delayed-type hypersensitivity induced by sheep red blood cells suggest that said anti-inflammatory activity is due to the effects of compounds expressed via a corticoid-like mechanism. In addition, the antioxidant activity …
Assessment of genetic variation in SicilianHelichrysum(Asteraceae) and implication to germplasm conservation
2008
Some taxa of Sicilian Helichrysum related to sect. Stoeachadina have an uncertain systematic position; moreover, they are rare and endangered. In order to preserve these taxa in a genebank, a strategy to keep their genetic variation as high as possible is required. The high informative content of AFLP markers was used to assess genetic variations within and between populations and their relationships. The results show that all populations are genetically similar, even though there are two distinct groups: the first is the population referred to H. pendulum, and the second is represented by other populations belonging to several different specific and intraspecific taxa. The H. pendulum popu…
Constituents of leaves and flowers essential oils of Helichrysum pallasii (Spreng.) Ledeb. growing wild in Lebanon.
2009
The chemical compositions of the essential oils obtained from leaves and flowers of Helichrysum pallasii were analyzed by gas chromatography and gas chromatography-mass spectrometry. Among the 102 identified constituents, hexadecanoic acid (16.2%), (Z,Z)-9,12-octadecadienoic acid (6.8%), tetradecanoic acid (2.6%), and (Z)-caryophyllene (4.2%) were the main constituent of the oil from leaves, while in the oil from flowers hexadecanoic acid (14.7%), (Z,Z)-9,12-octadecadienoic acid (14.2%), (Z)-caryophyllene (3.6%), and delta-cadinene (3.1%) predominated. The oils were both characterized by sesquiterpenes (33.4% for leaves and 33.7% for flowers, respectively) and fatty acids and esters (30.3% …
Analisi delle popolazioni siciliane di Helichrysum: propagazione in vitro e indagini fitochimiche
2004
The Sicilian populations of Helichisum have got a germoplasm from which it is possible to select ornamental plants to be placed in a mediterranean and/or dry climate. The in vitro trials show an attitude for microprapagation and multiplication for commerciaI productions that can be used also for the re·introduction in the natural habitat. The highest multiplication rate belongs to three genotypes: H. hyblaeum (clone S6), H. nebrodense (Clone Cli) and H. rupestre var. rupestre (clone S2, S11). The height and the feature of the vitro plants are pecuIiar for each different clone. The clone S11 is suitable for the production of pot plants or bushes, the clone S2 and S6 for garden edge. The clon…
Typification of Sicilian Helichrysum (Compositae) revisited
2007
Typification of the 13 validly published, pre-1958 names of Helichrysum taxa based on Sicilian material is reassessed. Five of the types designated by Galbany-Casals & al. in their recent studies are confirmed (in some cases with additional precision), two neotypes proposed by them are superseded by lectotypes, and six lectotypes are newly designated. The correct name of the species known as H. rupestre, an illegitimate name, is H. panormitanum (or, if taken in a wide sense, H. pendulum).
Taxonomic and nomenclatural novelties concerning the Valencian flora (eastern Spain)
2008
Como paso previo a la publicación de la cuarta edición del Manual para la determinación de la flora valenciana, que se encuentra en fase de edición, en la presente contribución se discute la identidad y valor taxonómico de algunas plantas iberolevantinas presentes en la Comunidad Valenciana. Como resultado se proponen cinco combinaciones nuevas, un nombre nuevo y se describen dos especies y una notospecie nuevas; asimismo se designan dos lectótipos. Para todas ellas se comentan aspectos nomenclaturales, taxonómicos, ecológicos y corológicos. Taxonomic and nomenclatural novelties concerning the Valencian flora (eastern Spain): Prior to publication of the fourth edition of Manual para la dete…
New acetophenone glucosides isolated from extracts of Helichrysum italicum with antiinflammatory activity.
2001
Three new acetophenone glucosides (4-6), three known aglycons (1-3), and a benzo-gamma-pyrone glucoside (7) were isolated from the CH(2)Cl(2), EtOAc, and BuOH extracts from the aerial parts of Helichrysum italicum. All the compounds tested showed antiinflammatory activity in a 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced mouse ear edema test, and the ID(50) value of compound 2, the most active compound, was determined.