Search results for "ESI-MS"
showing 10 items of 23 documents
New crystal structures of fluorinated α-aminophosphonic acid analogues of phenylglycine
2020
The four novel phosphonic acid analogues of phenylglycine with various substituents in phenyl ring (mostly fluorine atoms) have been synthesized by using procedure of amidoalkylation of phosphorus trichloride with aromatic aldehydes and acetamide. The NMR, ESI-MS spectroscopy, and single-crystal X-Ray diffraction methods were used to characterize unusual structures: the amino-(4-trifluoromethylbenzyl)-(1), amino-(3,4-difluorobenzyl)-(2), amino-(2,4,6-trifluorobenzyl)-(3), and amino-(2-fluoro-4-hydroxybenzyl)-(4) phosphonic acids. Since the α-aminophosphonates have a potential for biological activity and could be used as building blocks in medicinal chemistry, it is important to know their d…
Optimised method for the analysis of phenolic compounds from caper (Capparis spinosa L.) berries and monitoring of their changes during fermentation
2016
In this work, an ad hoc method to identify and quantify polyphenols from caper berries was developed on high-performance liquid chromatography/electrospray ionisation source/mass spectrometry (HPLC-ESI-MS). The method was applied during fermentation carried out with Lactobacillus pentosus OM13 (Trial S) and without starter (Trial C). A total of five polyphenols were identified. All samples contained high concentrations of rutin. Epicatechin was found in untreated fruits, on the contrary quercetin was detected during fermentation. Trial S was characterised by a more rapid acidification and lower levels of spoilage microorganisms than Trial C. L. pentosus dominated among the microbial communi…
First report on the presence of Alloxan in bleached flour by LC-MS/MS method
2017
Abstract In this work the presence of Alloxan in bread, pastry and cake bleached flour was investigate in order to verify possible risk for consumers related to the use of chemicals for flour bleaching. A selective UHPLC–MS/MS method has been developed and validated for the purpose. Alloxan is one of the possible minor side products of oxidation after chemical bleaching of wheat flours, when several chemical agents are used. One hundred and seventy-five flour samples were analyzed for Alloxan determination. The validation of the method was performed in accordance with the ISO/IEC/EN 17025 for linearity, detection limit, quantification limit, accuracy, precision and ruggedness determination.…
Coordination abilities of N-methyl alkylaminomethane-1,1-diphosphonic acids towards zinc(II), magnesium(II) and calcium(II) metal ions. Equilibrium s…
2017
Abstract Complex-formation abilities of a series of N-methyl alkylaminomethane-1,1-diphosphonic acids (1–7) with a common tertiary nitrogen atom (CH3−N−R) bearing linear or branched alkyl, cycloheptyl or phenylalkyl R substituents towards zinc(II), magnesium(II) and calcium(II) in aqueous solution have been studied by means of pH-potentiometry, ESI-MS spectrometry, 1H NMR and 31P NMR methods. The obtained results indicate that in the all presented systems mononuclear protonated equimolar and bis complexes are formed. In acidic and neutral solution, the formation of the protonated dinuclear species has been confirmed. The comparative analysis of the potentiometric and NMR data reveal that th…
Surfactant self-assembling in gas phase: electrospray ionization- and matrix-assisted laser desorption/ionization-mass spectrometry of singly charged…
2005
The self-assembling of sodium bis (2-ethylhexyl) sulfosuccinate (AOT) in gas phase has been investigated by electrospray ionization- and matrix-assisted laser desorption/ionization mass spectrometry. Large surfactant clusters with an aggregation number close to that found in apolar media have been observed either as positive or negative ions. Moreover, the marked predominance of singly charged species as well as preliminary theoretical calculations strongly suggest an aggregate structure characterized by an internal hydrophilic core hosting the extra charge surrounded by an apolar shell constituted by the surfactant alkyl chains. This structure is similar to that of the more familiar revers…
Phenolic Compounds Characterization and Antioxidant Properties of Monocultivar Olive Oils from Northeast Algeria
2020
In Algeria, the olive tree is one of the main fruit species and plays a very important socioeconomic role. The objective of this study was firstly, to identify and quantify the phenolics of some Algerian olive oils, and secondly, to assess the antioxidant activity of the samples. The olive oils used in this study were derived from Algerian cultivars, including Tefahi, Gelb Elfarroudj, Chemlal, and imported cultivar Manzanilla and Zebboudj. For this purpose, gas chromatography&mdash
Quality evaluation of extra-virgin olive oils from Sicilian genotypes grown in a high-density system
2019
Studying the sensory profile and chemical composition of monovarietal extra-virgin olive oils (EVOOs) is important to define and manage their quality and uniqueness. Chemical and sensory traits of olive oils from 14 minor Sicilian olive genotypes in comparison with oils from six major Sicilian and three international cultivars were analysed. Oils were extracted in 2015 from fruit of the 23 genotypes grown in an experimental orchard at a planting density of 1140 trees ha−1. Fatty acid composition, phenol composition, carotenoid content and antioxidant power were determined and analysed using univariate and multivariate procedures, in particular Nocellara Etnea along with carotenoid, phenol c…
Inhibitory Activity of Shrimp Waste Extracts on Fungal and Oomycete Plant Pathogens
2021
(1) Background: This study was aimed at determining the in vitro inhibitory effect of new natural substances obtained by minimal processing from shrimp wastes on fungi and oomycetes in the genera Alternaria, Colletotrichum, Fusarium, Penicillium, Plenodomus and Phytophthora
Color Stabilization of Apulian Red Wines through the Sequential Inoculation of Starmerella bacillaris and Saccharomyces cerevisiae
2021
Mixed fermentation using Starmerella bacillaris and Saccharomyces cerevisiae has gained attention in recent years due to their ability to modulate the qualitative parameters of enological interest, such as the color intensity and stability of wine. In this study, three of the most important red Apulian varieties were fermented through two pure inoculations of Saccharomyces cerevisiae strains or the sequential inoculation of Saccharomyces cerevisiae after 48 h from Starmerella bacillaris. The evolution of anthocyanin profiles and chromatic characteristics were determined in the produced wines at draining off and after 18 months of bottle aging in order to assess the impact of the different f…
Cucumis sativus l. Seeds ameliorate muscular spasm-induced gastrointestinal and respiratory disorders by simultaneously inhibiting calcium mediated s…
2021
Cucumis sativus L. is globally cultivated as an edible vegetable. Besides its nutritional benefits, it is used in traditional medicines against various ailments. The current study was designed to elucidate the multi-target mechanisms of a C. sativus seeds extract against asthma and diarrhea using network pharmacology along with a molecular docking approach. Furthermore, in-vitro and in-vivo experiments were conducted to verify the mechanistic insight of in silico studies. LC-ESI-MS/MS was performed to identify the bioactive compounds in the extract; later, some compounds were quantified by HPLC. C. sativus seed. EtOH has kaempferol in higher concentration 783.02 µg/g, followed by quercetin …