Search results for " chimica"
showing 10 items of 3438 documents
Electrochemical synthesis of coenzymes Qn by oxidation of tetramethoxy precursors
2009
The electrochemical oxidation of tetramethoxy precursors (2) to coenzymes Q (n) (1) at a carbon anode was investigated both in a bench-scale batch electrochemical reactor and in a continuous recirculation reaction system equipped with a parallel-plate electrochemical divided cell. High faradic efficiency (> 60%) and excellent selectivity (> 90%) in coenzymes Q (n) were obtained in CH3CN or CH3CN/CH2Cl2 + 0.15 M Bu4NBF4 under potentiostatic or amperostatic alimentation.
Photoelectrochemical evidence of nitrogen incorporation during anodizing sputtering--deposited Al-Ta alloys.
2015
Anodic films were grown to 20 V on sputtering-deposited Al–Ta alloys in ammonium biborate and borate buffer solutions. According to glow discharge optical emission spectroscopy, anodizing in ammonium containing solution leads to the formation of N containing anodic layers. Impedance measurements did not evidence significant differences between the dielectric properties of the anodic films as a function of the anodizing electrolyte. Photoelectrochemical investigation allowed evidencing that N incorporation induces a red-shift in the light absorption threshold of the films due to the formation of allowed localized states inside their mobility gap. The estimated Fowler threshold for the intern…
Anthemis wiedemanniana essential oil prevents LPS-induced production of NO in RAW 264.7 macrophages and exerts antiproliferative and antibacterial ac…
2012
Anthemis wiedemanniana is known in folk medicine for the treatment of microbial infections, cancer and also urinary and pulmonary problems. In this study, the chemical composition of the essential oil from A. wiedemanniana was evaluated and its antibacterial activity was tested against 10 bacterial strains. The oil was also tested for its potentiality to inhibit nitric oxide production in RAW 264.7 macrophages and for its cytotoxicity against four human cancer cell lines. A. wiedemanniana oil, rich of oxygenated monoterpenes (25.4%), showed a good antibacterial activity against Gram-positive bacteria and a good activity against the two Gram-negative bacteria, Escherichia coli and Proteus vu…
Metabolites from Mediterranean plants: characterization and transformation. Chemotaxonomic assessment and biological activity.
Questo progetto di ricerca ha lo scopo di ampliare le conoscenze di alcune piante appartenenti alla flora Mediterranea. Le piante da studiare sono state scelte in seguito ad un’attenta analisi bibliografica tra specie poco sudiate. La scelta è quindi ricaduta su nove specie appartenenti al genere Anthemis, due specie appartenenti al genere Pulicaria e sulle specie di Tetraclinis articulata, Salvia argentea, Ajuga tenorei, Ballota hispanica, Moluccella Spinosa e Thapsia garganica. Di esse sono stati preparati ed identificati i componenti degli oli essenziali e successivamente effettuati su di essi i saggi antibatterici. Dagli estratti delle specie di Tetraclinis articulata e Ajuga tenorei so…
Mapping quantitative trait loci affecting biochemical and morphological fruit properties in eggplant (Solanum melongena L.)
2016
Eggplant berries are a source of health-promoting metabolites including antioxidant and nutraceutical compounds, mainly anthocyanins and chlorogenic acid; however, they also contain some anti-nutritional compounds such as steroidal glycoalkaloids (SGA) and saponins, which are responsible for the bitter taste of the flesh and with potential toxic effects on humans. Up to now, Quantitative Trait Loci (QTL) for the metabolic content are far from being characterized in eggplant, thus hampering the application of breeding programs aimed at improving its fruit quality. Here we report on the identification of some QTL for the fruit metabolic content in an F2 intraspecific mapping population of 156…
Investigation on the influence of spray-drying technology on the quality of Sicilian Nero d’Avola wines
2018
The purpose of the present work was to find a correlation between microencapsulation technology applied to wines and the resulting quality of the wine itself in terms of volatile composition and phenolic profile. To this aim, samples of Nero d'Avola wines produced in Sicily (Italy) were investigated in order to: i) elucidate the aromatic composition by means of HSâSPME coupled with GCâMS; ii) assess the polyphenolic content by UHPLC mass spectrometry; iii) compare the results obtained from both the screenings with those relative to the same wines that had previously been subjected to spray-drying. The results showed a marked reductionThe results here obtained evidenced a marked reductio…
Anti-cancer activity of di- and tri-organotin(IV) compounds with D-(+)-Galacturonic acid on human tumor cells
2018
Abstract We have compared the anti-proliferative activity in vitro, of R2SnGala (1-3) [R = Me, n-Bu, Ph] and novel R3SnGala (4, 5) [R = Me, n-Bu] with D-(+)-Galacturonic acid [HGala; Galaq-, q = (2) and (1) for R2SnGala and R3SnGala, respectively] compounds, towards human tumor cell lines of intestinal carcinoma (HCT-116) and breast adenocarcinoma (MCF-7). The new synthesized 4 and 5 compounds were characterized, in solution, by 1H, 13C and 119Sn NMR, that showed that HGala acts as monoanionic moiety and evidenced the dynamic behavior of the compounds, due to inter-conversions involving the anomeric carbon atom of the ligand. Cell viability, apoptosis induction and cell cycle distribution w…
Synthesis of new 2,3-diaryl-1,3-thiazolidin-4-ones as anti-HIV agents
2004
Several 2,3-diaryl-1,3-thiazolidin-4-ones were synthesized and evaluated as anti-HIV agents. The results of the in vitro tests showed that some of them were highly effective inhibitors of HIV-1 replication at 30-50 nM concentrations with minimal cytotoxicity, thereby acting as non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs).
Eight-Membered Rings With Two Heteroatoms 1,3
2022
Eight-membered rings with two heteroatoms in a 1,3-relationship, namely 1,3-diazocine, 2H-1,3-oxazocine, 2H-1,3-thiazocine, 4H-1,3-dioxocin, 4H-1,3-oxathiocin, and 4H-1,3-dithiocin, are discussed in this chapter, that covers the literature from 2007 to October 2020 (SciFindern search) and reports the chemistry of uncondensed derivatives, heterocines fused to carbocycles and heterocycles, as well as bridged heterocines. Among eight-membered 1,3-diheterocines, 1,3-diazocines and 1,3-oxazocines are the two largest classes, based on the number of publications, mostly due to the studies of the synthesis of these cyclic systems, their pharmacological properties and/or their important industrial a…
Chemical composition of the essential oil from Thapsia garganica L. (Apiaceae) grown wild in Sicily and its antimicrobial activity.
2015
In this study, the chemical composition of the essential oil from flowers and leaves of Thapsia garganica L. collected in Sicily was evaluated by GC and GC-MS. The main components of T. garganica flower oil (T.f.) were chamazulene (58.3%), humulene oxide II (9.0%), tricosane (8.2%) and pentacosane (8.2%). Also the oil from leaves (T.l.) was characterised by high content of chamazulene (49.2%). Other abundant metabolites were 1,4-dimethylazulene (18.5%), (E)-phytol (6.3%) and neophytadiene (5.1%). The comparison with other studied oils of genus Thapsia is discussed. Antimicrobial activity against several micro-organisms, including some ones infesting historical art craft, was also determined.