Search results for "GC-MS"
showing 10 items of 96 documents
PAHs associated with the leaves of Quercus ilex L.: Extraction, GC–MS analysis, distribution and sourcesAssessment of air quality in the Palermo (Ita…
2007
Abstract In this study, the leaves of Quercus ilex L. were selected as possible bioaccumulators of polycyclic aromatic hydrocarbons (PAHs). Quercus is an evergreen plant that occurs widely in both urban and rural areas. Several sites (urban roadside, urban, urban park, suburban and rural) in and around Palermo city were investigated. The purpose of this research was to optimize analytical method for quercus leaves, investigate the degree of contamination in the urban area of Palermo by comparing PAH concentration in leaves of quercus from the several sites, establish distribution patterns and relate them to possible sources of PAHs. To this aim, the 16 recommended as priority pollutants by …
Gas chromatography-mass spectrometry study of polycyclic aromatic hydrocarbons in grass and milk from urban and rural farms
2000
Polycyclic aromatic hydrocarbon (PAH) levels were studied in grass and milk sampled at two farms, one located in a non-contaminated, rural area, and another located in a urban area close to PAH sources such as highways, busy roads, fuel-powered trains and a steel plant. PAH concentration were measured by gas chromatography coupled to mass spectrometry (GC-MS) using internal deuterated standards. In grasses, unexpectedly, although the sum of PAH concentrations was only slightly higher at the urban farm (83.1 ± 16.1 ng g−1) than the rural farm (51.8 ± 10.6 ng g−1), this difference was not observed for all PAH members. This absence of a striking difference of PAH levels between urban and rura…
CHEMICAL AND BOTANICAL CHARACTERIZATION OF A ROSMARINUS OFFICINALIS L. BIOTYPE FROM SICILY
2006
Rosemary (Rosmarinus officinalis L.) is widely cultivated all over the world as ornamental and aromatic plant. Today, the interest towards its cultivation is strongly arising, due to the many biological activities exerted by the essential oil extracted from its leaves and flowers. Which compounds confer to Rosemary's essential oil its properties is still unclear, but it seems likely that these effects must be attributed to a mixture of different principles, acting contemporarily and synergically. The diverse composition of the essential oils of Rosemary's ecotypes coming from different geographical areas could be the reason of their various level of activity. With the aim of obtaining furth…
The essential oil composition of Centaurea immanuelis-loewii Degen growing wild in Bulgaria and chemotaxonomy of section Acrocentron
2021
In the present study, the chemical composition of the essential oil from aerial parts of the Balkan endemic, Centaurea immanuelis-loewii Degen (sect. Acrocentron, Asteraceae), collected in Bulgaria was evaluated by GC-MS. The main components of the oil were β-caryophyllene (23.2%), germacrene D (13.7%) and caryophyllene oxide (12.4%). Furthermore, a complete literature review on the composition of the essential oils of all the other taxa of Centaurea, belonging to section Acrocentron, studied so far, was performed and the chemotaxonomical variations in the composition of the essential oils is discussed.
Indagini di laboratorio sui composti che inducono l'aggregazione delle neanidi di I età in Leptoglossus occidentalis (Hemiptera, Coreidae)
2011
Leptoglossus occidentalis è una cimice che si alimenta degli strobili e dei semi delle conifere appartenenti alla famiglia delle Pinaceae. Le neanidi di I età hanno un comportamento gregario che favorisce la sopravvivenza degli individui, in analogia a quanto visto in altre specie appartenenti allo stesso genere (Wheeler et al., 1990). L’individuazione dei composti semiochimici che influenzano questo comportamento potrebbe portare allo sviluppo di nuovi metodi di controllo di L. occidentalis. Le estrazioni (whole body) sono state realizzate su gruppi di 7-27 neanidi di I età per 30 minuti utilizzando un quantitativo di 40µl di esano o di acetone per neanide. Gli estratti sono stati biosaggi…
Il feromone sessuale a breve raggio del parassitoide oofago Trissolcus brochymenae
2009
Il comportamento sessuale dei parassitoidi presenta una fase di pre-copula, in cui si ha ricerca, corteggiamento e riconoscimento dell’altro sesso, alla quale seguono le fasi di copula ed eventualmente post-copula. Durante la pre-copula, la localizzazione e il riconoscimento sono per lo più stimolati da composti feromonali con diversa volatilità. I composti feromonali ad alta volatilità, rilasciati dalle femmine, sono utilizzati dai maschi per l’orientamento a lunga distanza, mentre quelli scarsamente volatili mediano il comportamento di corteggiamento. In questo lavoro si riportano dati sperimentali sul feromone sessuale a breve raggio emesso dalle femmine di Trissolcus brochymenae (Hymeno…
Sexual communication in the egg parasitoid Trissolcus brochymenae
2009
The males of the egg parasitoid Trissolcus brochymenae (Hymenoptera Scelionidae) exploit a short range pheromone for recognition of the other gender. To evaluate the role of this pheromone, the behavior of virgin males has been studied in closed arena when exposed to the following cues: 1) virgin females (alive, dead "washed" with solvents, dead" unwashed"); 2) dissected and re-assembled virgin females (females dissected into head, mesosoma, and gaster, then reassembled using two solvent "washed" parts and an "unwashed” part, or "unwashed" legs assembled with entire" washed" body); 3) "washed" females treated with acetone extracts (of virgin females and of legs). Males antennate and mount v…
Modifications over time of volatile compounds in coriander (Coriandrum sativum L.)
2007
Coriander (Coriandrum sativum L.) is an annual strongly-smelling herb belonging to the family Apiaceae, which is cultivated all over the world for its aromatic fruits (“seeds”) and, in many Asiatic and South American countries, for its green leaves. The aromatic features of leaves and fruits are sharply different, and the strong smell coming from leaves (many times referred to as a “bug” scent) is not always pleasant to many consumers from western countries. In our work, one Coriander small-seeded biotype has been grown in plastic covered greenhouses, and at given time intervals samples of leaves, flowers and fruits have been analyzed by means of HS-SPME and GC-MS to study the evolution ove…
Influence of "single-origin" coffees on sensory characteristics of Espresso.
2004
Screening of Ovarian steroidogenic pathway in Ciona intestinalis and its modulation after Tributyltin exposure
2010
In this study, we have identified several ovarian steroids in Ciona with high similarity to vertebrate steroids and showed that cholesterol, corticosterone, dehydroepiandrosterone, estrone, estradiol-17beta, testosterone, pregnenolone, progesterone, have identical molecular spectra with vertebrate steroids. In addition, we have studied the effects of an endocrine disruptor (tributyltin: TBT) on these sex hormones and their precursors, ovarian morphology, and gene expression of some key enzymes in steroidogenic pathway in the ovary of Ciona. Ovarian specimens were cultured in vitro using different concentrations of TBT (10{sup -5}, 10{sup -4} and 10{sup -3} M). Ethanol was used as solvent co…