Search results for "FLOWER"

Chemical composition, antimicrobial and antioxidant activity of the essential oils from Pimpinellatragium Vill. subsp. glauca (C. Presl.) C. BrulloBr…

2013

The essential oils from flowers, leaves and stems hydrodistilled from Pimpinella tragium Vill, subsp. glauca were characterised by GC and gas chromatography-mass spectrometry analysis. The C-12 nor-sesquiterpenes are the principal class of metabolites (56.6-70.6%) among which geijerene (28.9÷49.3%) and pregeijerene (10÷19.1%) predominate. Antimicrobial and antioxidant activities were evaluated. The minimum inhibitory concentration values indicate that oil obtained from the stems is the most active for antimicrobial activities and the sample with the biggest antioxidant capacity is the flower oil.

Micropropagazione di Platycodon grandiflorus

2009

Survey of the parasitoids of the European Sunflower MothHomoeosoma nebulella [Lep.: Pyralidae] in the palearctic region

1993

The European Sunflower MothHomoeosoma nebulella Denis & Schiffermuller is a potential pest on sunflower in France. The parasitoids of this moth are little known. We present here original data obtained in the south of France together with previous survey. Some parasitoids we found were new records onH. nebulella. The relative weakness of the parasite complex ofH. nebulella (less than 15 species) compared to that of the American Sunflower MothH. electellum (Hulst) is discussed.

Mycorrhizal benefit differs among the sexes in a gynodioecious species

2010

Both plant sex and arbuscular mycorrhizal (AM) symbiosis influence resource acquisition and allocation in plants, but the interaction between these two components is not well established. As the different plant sexes differ in their resource needs and allocation patterns, it is logical to presume that they might differ in their relationship with AM as well. We investigate whether the association with AM symbiosis is different according to the host plant sex in the gynodioecious Geranium sylvaticum, of which, besides female and hermaphrodite plants, intermediate plants are also recognized. Specifically, we examine the effects of two different AM fungi in plant mass allocation and phosphorus …

Allium therinanthum (Amaryllidaceae), a new species from Israel

2014

Allium therinanthum, a new species of A. sect. Codonoprasum, is described and illustrated from southern Mt. Hermon (Israel). It is a late-flowering diploid species (2n = 16), growing on calcareous substrates of the mountain belt. It is a narrowly distributed geophyte, showing morphological relationships mainly with A. tardiflorum, a typical autumnal species also occurring in Israel within the pinewoods of Mt. Carmel. The morphology, karyology, leaf anatomy, ecology, conservation status and taxonomical relations are examined for both species. A taxonomic comparison with the most allied late flowering species of the sect. Codonoprasum is provided.

Floral Diversity and Pollen Transfer Mechanisms in Bird-pollinated Salvia Species

2007

† Background and Aims Bird-pollinated (ornithophilous) Salvia species (sages) transfer pollen either by means of a staminal lever mechanism or by immovable stamens. As the distribution of the two modes within the genus is not known, we present a survey of all ornithophilous sages. The main focus is given to floral diversity especially with respect to functional lever morphology. Thereby the hypothesis is tested that, due to a pollinator shift from bees to birds, the lever mechanism became unnecessary. † Methods To get a general idea about the diversity of pollen transfer mechanisms, 186 ornithophilous Salvia species were classified according to the functional morphology of the stamen and th…

Flower roundabouts: estimation of capacity and level of service

2012

The research work on road junction geometry, carried out in European research centres, has recently allowed to design new road intersection types which are of undoubted interest, especially in terms of traffic functionality and safety. Among the most interesting solutions there are such schemes as spiral, turbo and flower roundabouts, which are similar to traditional roundabouts. Although these solutions provide a traffic travels counterclockwise around a central island and in which entering traffic must yield to circulating traffic, the newly designed schemes generally offer modes of traffic flow regulations which highly differ from those used in conventional roundabouts. Of considerable i…

Determination of unsaturation grade and trans isomers generated during thermal oxidation of edible oils and fats by FTIR

1999

Abstract The oxidative deterioration of culinary oils and fats during episodes of heating associated with normal usage (80°C–300°C, 20–40 min) was monitored by FTIR spectroscopy. The thermal oxidation of polyunsaturated fatty acids during heating was studied by the determination of unsaturation percentage and trans isomers at various temperatures and heating times. Oils frequently used in food frying such as olive oil, sunflower oil, corn oil and seeds oil (sunflower, safflower and canola seed), and lard were studied. The Absorbance Correction Method is proposed to correct the spectral interference and allows the analytic use of signal which would not be initially valid for quantitative ana…

Analytical evaluation of polyunsaturated fatty acids degradation during thermal oxidation of edible oils by Fourier transform infrared spectroscopy

1998

The oxidative deterioration of polyunsaturated fatty acids (PUFAs) in culinary oils and fats during episodes of heating associated with normal usage (80-300 degrees C, 20-40 min) has been monitored by Fourier transform infrared spectroscopy (FTIR). The thermal oxidation of PUFAs is a free radical chain reaction, in which hydroperoxides are generally recognized as the primary major products. Hydroperoxides of PUFAs are easily decomposed into a very complex mixture of secondary products with the decrease in unsaturation. The oxidative advance of PUFAs during heating was studied by the determination of unsaturation percentage at different temperatures and heating times. Oils frequently used in…

From linear quaterthiophene to sulflower: A comparative theoretical study

2009

Abstract In this paper, we report a theoretical study of four types of thiophene-based oligomers showing the same number of C C double bonds and very different molecular structures. The comparative study has been performed on the basis of B3LYP/6-31G∗∗ calculations. The way the thiophene rings are linked together has a remarkable influence on the molecular and electronic properties. Linear quaterthiophene and heptathienoacene show similar aromatic structures but a loss of π-conjugation is detected for the latter due to the condensation of thiophene rings. A blue shift of the most intense electronic transition is predicted for fused heptathienoacene compared with non-fused quaterthiophene. C…