Search results for "HPLC"

HPLC Determination of Polyphenols from Calendula officinalis L. Flowers

2017

Abstract Romanian spontaneous flora provides a lot of resources for the determination of different chemical compounds. This study uses flower samples from Calendula officinalis L. extracted through maceration. The chemical compounds determined were: (+)-catechin, caffeic acid, chlorogenic acid, cinnamic acid, ferulic acid, gallic acid, rutin, resveratrol and quercetin. They were analyzed by using an optimized HPLC method. (+)-Catechin, caffeic acid, chlorogenic acid and quercetin could not be identified in the analyzed samples. The greatest amount of phenolic compound found was rutin and the smallest quantity was determined for ferulic acid. The quantified compounds have proven to have bene…

HYDROCARBONS REMOVAL FROM BILGE WATER BY ADSORPTION ONTO ACTIVATED BIOCHAR FROM POSIDONIA OCEANICA

2019

The normal operations carried out on the boats during navigation generate waste waters such as oily bilge water. The latter is the aqueous mixture of potential pollutants of different origins and types: oily fluids, lubricants and greases, cleaning fluids and other wastes that accumulate in the lower part of the vessel [1,2]. The current legislation provides that they can be discharge directly into the sea if the concentrations of some components are below the expected limits. In particular, with regard to oil / hydrocarbons contamination, the current regulatory limit is 15 mg L-1 of total hydrocarbons. The present work starts from a public/private partnership funded by a grant of the Minis…

Photografted methacrylate-based monolithic columns coated with cellulose tris(3,5-dimethylphenylcarbamate) for chiral separation in CEC

2018

A chiral capillary monolithic column for enantiomer separation in capillary electrochromatography was prepared by coating cellulose tris(3,5-dimethylphenylcarbamate) on porous glycidyl methacrylate-co-ethylene dimethacrylate monolith in capillary format grafted with chains of [2(methacryloyloxy)ethyl] trimethylammonium chloride. The surface modification of the monolith by the photografting of [2(methacryloyloxy)ethyl] trimethylammonium chloride monomer as well as the coating conditions of cellulose tris(3,5-dimethylphenylcarbamate) onto the grafted monolithic scaffold were optimized to obtain a stable and reproducible chiral stationary phase for capillary electrochromatography. The effect o…

Ruta chalepensis L. (Rutaceae) leaf extract: chemical composition, antioxidant and hypoglicaemic activities.

2017

Ruta chalepensis L. (Rutaceae) leaf extract was investigated for its chemical profile and antioxidant and hypoglycaemic properties. The antioxidant effects were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), Chi-carotene bleaching, and metal chelating activity assays. The carbohydrate-hydrolysing enzymes inhibition assay was used to test the hypoglycaemic potential. R. chalepensis showed a high content of hesperidin and rutin with values of 591.9 and 266.7 mg/g dry extract, respectively. The extract exhibited a promising protection of lipid peroxidation (IC50 value of 16.9 mu g/mL) and inhibited both alpha-amylase and alpha-glucosidase enzymes in a concentration-dependent manner. The…

Gender-related variations in hemolymph parameters of Carabus lefebvrei (Coleoptera: Carabidae): HPLC analysis and phenoloxidase activity

2017

We characterized the enzymatic activity of basal and total phenoloxidase and HLPC and SDS- PAGE profiles in hemolymph of Carabus lefebvrei males and females at different reproductive status. The phenoloxidase activity was activated by trypsin and inhibited by phenoloxidase activity specific inhibitor phenylthiourea. Our results demonstrated that both in males and females, there were no significant differences in the basal phenoloxidase activity between reproductive and virgin beetles, while the total phenoloxidase activity increased significantly in virgin specimens. Thus, resources seem to be invested to increase the humoral response in pre-reproductive phase forming a barrier against path…

Lignānu identificēšana un daudzuma izvērtējums linsēklās, izmantojot hromatogrāfiskās analīzes metodes

2017

Darbā ir analizēts lignānu daudzums sešos dažādas izcelsmes linsēklu paraugos, pielietojot šķidruma hromatogrāfijas masspektrometrijas metodi. Pētījumā veikta linsēklu tēju un pašu linsēklu analīze, izmantojot ekstrakcijas metodi. Rezultātā paraugos identificēti astoņi lignāni, kuru vidējais kopējais daudzums linsēklu tējās sastādīja 39,59 mg/100 g, bet, pielietojot ekstrakcijas metodi, vidējā kopējo lignānu masas koncentrācija sastādīja 145,51 mg/100 g.

Triacylglycerol Analysis in Human Milk and Other Mammalian Species: Small-Scale Sample Preparation, Characterization, and Statistical Classification …

2015

In this work, a method for the separation of triacylglycerols (TAGs) present in human milk and from other mammalian species by reversed-phase high-performance liquid chromatography using a core–shell particle packed column with UV and evaporative light-scattering detectors is described. Under optimal conditions, a mobile phase containing acetonitrile/n-pentanol at 10 °C gave an excellent resolution among more than 50 TAG peaks. A small-scale method for fat extraction in these milks (particularly of interest for human milk samples) using minimal amounts of sample and reagents was also developed. The proposed extraction protocol and the traditional method were compared, giving similar results…

Characterization of the synthetic cannabinoid MDMB-CHMCZCA

2016

The synthetic cannabinoid MDMB-CHMCZCA was characterized by various spectroscopic techniques including NMR spectroscopy and tandem mass spectrometry. The synthetic sample was found to be of S-configuration by VCD spectroscopy and comparison of the data with DFT calculations, while ECD spectroscopy was found to be inconclusive in this case. The enantiomeric purity of samples from test purchases and police seizures was assessed by a self-developed chiral HPLC method.

COMPARAZIONE DEI PROFILI METABOLICI DI VARIETÀ DI CILIEGIO DOLCE (Prunus avium L.) MEDIANTE TECNICHE DI METABOLOMICA UNTARGETED

La diffusione di cultivar altamente produttive ha influito negativamente sulla tutela dell’agro-biodiversità di Prunus avium L. determinando disinteresse nei confronti di varietà meno produttive ma meritevoli di attenzione per il valore delle loro caratteristiche organolettiche e del relativo patrimonio genetico. Il mondo scientifico ha mostrato interesse nei confronti di tale tematica e ha condotto azioni di conservazione in situ ed ex situ per preservare il germoplasma ancora esistente. La presente ricerca analizza l’agrobiodiversità del ciliegio dolce in relazione alla diversa composizione metabolomica dei frutti, espressione del genotipo che le caratterizza. L’attività di ricerca svolta…

Identification and quantification of phosphatidylcholines containing very long chain polyunsaturated fatty acid (VLC-PUFA) in bovine and human retina…

2010

The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA). A large proportion of the retinal glycerophospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine molecular species are known to contain very long chain polyunsaturated fatty acids (VLC-PUFA) from the n-3 and n-6 series and having 24 to 36 carbon atoms (C24 to C36) and four to six double bonds. Recent interest in the role of VLC-PUFA arose from the findings that a protein named ELOngation of Very Long chain fatty acids 4 (ELOVL4) is involved in their biosynthesis and that mutations in E…