323,089 research outputs found
Caratterizzazione chimica della componente volatile di bucce e succhi di Citrus species tramite SPME-GC/MS
No full textGC-MS and SPME-GC/MS analysis and bioactive potential evaluation of essential oils from two viola species belonging to the V. calcarata complex
No full textViola calcarata L. and Viola dubyana Burnat ex Gremli belong to the V. calcarata complex in Viola section Melanium (Violaceae family). For the first time, the essential oils (EOS) obtained by hydrodistillation from dried flowers, were analyzed by GC/MS and SPME-GC/MS to describe their volatile chemical profile. Differences in the qualitative and quantitative composition between the two violets have been found. A total of 43 compounds were identified among which methyl salicylate was the most abundant (from 45.5 to 68.0%) both in the vapor and liquid phase. The performed bioactivity tests pointed out the greater effect of V. dubyana EO compared to that obtained from V. calcarata. Nevertheless, both EOs proved to be good scavengers, especially toward the ABTS⋅+ radical. They also showed a dose-dependent phytotoxic action against Sinapis alba and Lolium multiflorum. Their seed germination was inhibited up to 100% and 25%, respectively, in response to the highest used dose (100 μL) of each EO. Furthermore, a significant decrease in root and shoot length was observed. The resulting seedling vigor index was reduced by 15–100% and 8–82% for S. alba and by 11–91% and 4–91% for L. multiflorum by V. dubyana and V. calcarata EOS, respectively
GC-MS and SPME-GC/MS analysis andbioactive potential evaluation of essential oils from two Viola species belonging to the V. calcarata complex
No full textViola calcarata L. and Viola dubyana Burnat ex Gremli belong to the V. calcarata complex in Viola section Melanium (Violaceae family). For the first time, the essential oils (EOS) obtained by hydrodistillation from dried flowers, were analyzed by GC/MS and SPME-GC/MS to describe their volatile chemical profile. Differences in the qualitative and quantitative composition between the two violets have been found. A total of 43 compounds were identified among which methyl salicylate was the most abundant (from 45.5 to 68.0%) both in the vapor and liquid phase. The performed bioactivity tests pointed out the greater effect of V. dubyana EO compared to that obtained from V. calcarata. Nevertheless, both EOs proved to be good scavengers, especially toward the ABTS⋅+ radical. They also showed a dose-dependent phytotoxic action against Sinapis alba and Lolium multiflorum. Their seed germination was inhibited up to 100% and 25%, respectively, in response to the highest used dose (100 μL) of each EO. Furthermore, a significant decrease in root and shoot length was observed. The resulting seedling vigor index was reduced by 15–100% and 8–82% for S. alba and by 11–91% and 4–91% for L. multiflorum by V. dubyana and V. calcarata EOS, respectively
ANALISI CHIMICA PER LA CARATTERIZZAZIONE DEL PROFILO VOLATILE DEGLI OLI ESSENZIALI E DEGLI IDROLATI OTTENUTI DALLE PIANTE DI THYMUS VULGARIS L. TRATTATE CON LED
No full textGli oli essenziali (EOs) sono miscele complesse costituite da un numero elevato di metaboliti secondari appartenenti a diverse classi chimiche, caratterizzati da una considerevole volatilità e termolabilità. La tecnica strumentale più idonea alla caratterizzazione chimica di un EO è la gas-cromatografia, accoppiata alla spettrometria di massa (GC-MS), in quanto in grado di fornire informazioni riguardanti sia la composizione qualitativa che quantitativa. Per quanto riguarda gli idrolati, essendo matrici acquose e quindi non iniettabili direttamente nel GC, necessitano prima di essere sottoposte ad una fase di campionamento al fine di catturare i composti volatili, per essere successivamente analizzate con la GC-MS. La tecnica dello spazio di testa strumentale (Headspace technique), si presta perfettamente a tale scopo in quanto, essendo conservativa e non distruttiva, permette di campionare la fase vapore in equilibrio con il liquido sottostante (1,2). Nel caso specifico, l’idrolato viene posto all’interno di una headspace vial, dotata di un tappo forabile sigillato e alloggiata sul carosello dell’autocampionatore. La vial viene quindi riscaldata ad una temperatura opportuna e per un tempo adeguato tali da consentire il passaggio in fase vapore dei componenti volatili; una serie di parametri strumentali viene ottimizzata per il raggiungimento della fase di equilibrio. A questo punto un flusso di gas inerte (He) verrà convogliato all’interno della vial, inizialmente per garantire una omogenizzazione della fase vapore e successivamente per effettuare l’estrazione dei componenti che verranno quindi inviati, tramite una transfer-line, direttamente nel GC. L’utilizzo di questa tecnica garantisce l’estrazione di composti volatili da una matrice acquosa senza ricorrere all’uso di solventi organici estrattivi, evitando così una serie di problematiche ad essi legate tra cui l’eventuale perdita di analiti e/o la creazione di artefatti.
I tre EOs di Thymus vulgaris L. (A:50 μmol m-2 s-1; B:75 μmol m-2 s-1; C: Controllo) provenienti dalla prova sperimentale allestista nel 2021 presso le Serre dell’Università di Bologna, sono stati investigati per iniezione diretta nel GC-MS. Le analisi condotte hanno evidenziato una ricca composizione in monoterpeni e sesquiterpeni con cromatogrammi pressoché sovrapponibili tra il controllo (C) ed i due campioni trattati con LED (A, B), ma con delle differenze quantitative rilevate a carico di alcuni componenti (Fig. 1).
I tre idrolati di T. vulgaris L. sono stati sottoposti ad analisi tramite HS-GC-MS, ottenendo delle marcate differenze tra il controllo C e i due campioni A e B sottoposti a LED.
In generale, i risultati ottenuti si sono dimostrati essenziali per capire quali modifiche, a carico del profilo chimico volatile, vengono indotte dal trattamento con i LED. Tra l’altro, i dati estrapolati sono fondamentali anche per individuare quale, tra i due trattamenti, risulti il più idoneo tenendo conto della diversa espressione dei metaboliti secondari ossia delle variazioni percentuali a loro carico. Queste indagini preliminari rappresentano le basi per una ottimizzazione di quei parametri luminosi che sono stati presi in considerazione per l’irradiazione delle piante di T. vulgaris L
Solanum linnaeanum Leaves: Chemical Profiling of {VOCs} and Effects on Seed Germination and Early Growth of Monocots and Dicots
No full textSome Solanaceae plants are a rich source of sesquiterpenoid phytoalexins with allelopathic potential. Powder and aqueous extract obtained from the leaves of Solanum linnaeanum Hepper & P.M.L. Jaeger were used to treat the seeds of three target species (Lolium multiflorum Lam., Sinapis alba L. and Trifolium incarnatum L.). Both matrices were evaluated along with untreated controls to determine their toxicity on germination and seedling growth. The results revealed that the pre-emergence treatments were able to be very effective against all three species in the filter paper test by inhibiting the germination up to 100 %. The effectiveness was reduced by the interaction with soil. Despite this, significant data were obtained, albeit different according to the applied matrix. In general, L. multiflorum was the most sensitive to both the action of the leaf powder and aqueous extract while S. alba was found to be the most resistant to powder activity and T. incarnatum had the strongest response to the extract. For the first time, SPME-GC/MS technique was used to characterize the volatile chemical profile of S. linnaeanum leaves. The analyses highlighted the presence of different classes of compounds including terpenoids and sesquiterpenoids potentially useful in the fight against noxious plants both in natural and cultivated ecosystems
Analisi del contenuto stomacale di Procambarus clarkii (Girard 1852), gambero invasivo nella riserva naturale “Borsco S. Negri” (Zerbolò, PV)
No full textCaratterizzazione chimica quali-quantitativa della fase vapore degli oli essenziali
No full textGli oli essenziali sono prodotti naturali estratti da piante che generalmente presentano una composizione chimica piuttosto complessa. Si tratta di miscele ricche di composti volatili e termolabili come monoterpeni, sesquiterpeni e loro derivati ossigenati. La gascromatografia accoppiata alla spettrometria di massa è ampiamente utilizzata come tecnica analitica di separazione per l'identificazione e la quantificazione dei costituenti volatili della miscela chimica. La tecnica dello spazio di testa (HS) accoppiata al sistema cromatografico viene applicata come metodo di estrazione della fase vapore. Il campione, posto in una fiala chiusa viene riscaldato ad una temperatura tale da favorire il passaggio dei composti nella fase vapore. Tramite l’utilizzo di un gas inerte (He), avviene l’estrazione di tali componenti che verranno convogliati al gas cromatografo mediante l’utilizzo di una transfer-line. Si tratta di una tecnica estrattiva facilmente applicabile e particolarmente efficace soprattutto quando i composti volatili devono essere separati da una matrice liquida prima dell'analisi gas cromatografica evitando così una serie di problematiche legate all' uso dei solventi di estrazione
Viola calcarata L. and Viola dubyana Burnat ex Gremli hydrolates: DI-SPME-GC-MS analysis and biological activity evaluation
No full textThe hydrolates obtained from the aerial parts
of two indigenous Viola L. species (V. calcarata L. and V.
dubyana Burnat ex Gremli) growing in the Italian Alps
were studied for the first time. The direct immersion
solid-phase microextraction (DI-SMPE) sampling and
the GC–MS analysis revealed the presence of methyl
salicylate as the main compound in both samples along
with a different set of terpenes for each hydrolate and
some other minor compounds. The most interesting
results were achieved by evaluating their phytotoxic
potential against two target species (Sinapis alba L. and
Lolium multiflorum Lam.) through treatments without
direct contact with the seeds. In general, the hydrolates
showed species and dose-dependent effects. They
were more active on growth (maximum reduction =
-86.8% due to V. dubyana hydrolate on S. alba) than on
germination (maximum inhibition = -45.9% due to V.
calcarata hydrolate on S. alba). No sig
A comparative study of the chemical composition by spme-gc/ms and antiradical activity of less common citrus species
No full textCitrus secondary metabolites, such as terpene compounds, are very important for human health due to their bioactivity including anti-inflammatory, anti-cancer, and antioxidant effects. In this work, for the first time, the volatile chemical composition of peels and juices from four different Citrus species (C. junos, Citrus × aurantium, C. aurantium ‘Bizzarria’ and C. medica ‘Florentina’, commonly known as Yuzu jeune, Oni Yuzu, Bizzarria orange and Florence cedar, respectively) was investigated by Solid-Phase Microextraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS) technique and the antiradical activity was also examined. The results showed that limonene and γ-terpinene were the main volatile substances detected both in the juices and in the peels, followed by other minority compounds responsible for the phyto-complex of the unique aromas which characterize each individual analyzed Citrus species. Principal component analysis (PCA), performed on volatile compounds, showed both some correlation as well as a clear separation between the juice and the peel of each species. Among them, Oni Yuzu juice was found to be the richest in total polyphenols and flavonoids while its capacity to scavenge ABTS•+ and DPPH• radicals was similar to that of Yuzu Jeune and Bizzarria orange
Foeniculum vulgare miller, a new chemotype from Montenegro
No full textPrevious studies relating to prolonged and fractionated distillation procedures highlighted essential oils’ (EOs) chemical composition to be significantly dependent on the extraction duration and harvesting time. As a continuation, a hydrodistillation procedure was applied to ripe fruit material of fennel, Foeniculum vulgare Miller (Apiaceae), collected from three localities in Montenegro (Podgorica, Nikšić, and Kotor) to furnish a total of 12 EOs. Liquid and vapor phases of the samples were analyzed by Gas Chromatography/Mass Spectrometry and Headspace-Gas Chromatography/Mass Spectrometry techniques, and 18 compounds have been identified. Although both quantitative and qualitative differences between the samples were notable, the phenylpropanoids anethole (ANE) and estragole and the monoterpenoids α-terpineol (TER) and fenchone (FEN) could be singled out as the most abundant constituents. The EOs from Podgorica belong to the most common ANE-rich chemotype, while the predominance of the monoterpenoid fraction is characteristic of the samples from Nikšić and Kotor. The latter is particularly rich in TER (up to 56.5%), with significant amounts of FEN and ANE. This chemical profile could represent a new chemotype of fennel EO. Vapor phases contained mainly monoterpenoids, with increased amounts of FEN and TER, while the number of phenylpropanoids was significantly decreased
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