Search results for "HPLC"

Age-dependent regulation of antioxidant genes by p38α MAPK in the liver

2018

p38α is a redox sensitive MAPK activated by pro-inflammatory cytokines and environmental, genotoxic and endoplasmic reticulum stresses. The aim of this work was to assess whether p38α controls the antioxidant defense in the liver, and if so, to elucidate the mechanism(s) involved and the age-related changes. For this purpose, we used liver-specific p38α-deficient mice at two different ages: young-mice (4 months-old) and old-mice (24 months-old). The liver of young p38α knock-out mice exhibited a decrease in GSH levels and an increase in GSSG/GSH ratio and malondialdehyde levels. However, old mice deficient in p38α had higher hepatic GSH levels and lower GSSG/GSH ratio than young p38α knock-…

Use of triacylglycerol profiles established by high performance liquid chromatography with ultraviolet–visible detection to predict the botanical ori…

2011

A method for the determination of triacylglycerols (TAGs) in vegetable oils from different botanical origins by HPLC with UV–vis detection has been developed. Using a core-shell particle packed column (C18, 2.6 micron), TAG separation was optimized in terms of mobile phase composition and column temperature. Using isocratic elution with acetonitrile/n-pentanol at 10 °C, excellent efficiency with good resolution between most of the TAG peak pairs, within a total analysis time of 15 min, was achieved. Using mass spectrometry detection, a total of 15 peaks, which were common to oils of six different botanical origins (corn, extra virgin olive, grapeseed, hazelnut, peanut and soybean) were iden…

INFLUENCE OF BIOTIC AND ABIOTIC FACTORS ON QUALITY AND SECONDARY METABOLITES OF ‘VALENCIA’ ORANGE FRUITS

2014

Chemical composition, cytotoxic effects, antimicrobial and antibiofilm activity of Artemisia arborescens (Vaill.) L. growing wild in the province of …

2022

Artemisia arborescens (Vaill.) L. is a perennial shrubby plant growing along the coastal strips of the Mediterranean region. It is used in traditional medicine. Its essential oil and solvent extracts exhibit a very interesting chemotherapeutic potential, which makes this plant useful in maintaining human health. The goal of this study was to determine the phytochemical composition of the petroleum ether and methanol extracts, as well as to evaluate anticancer activities and antimicrobial and biofilm formation reduction. Thirty-nine phytochemical compounds in negative ion mode, and 25 in positive ion mode were identified by HPLC-ESI-QTOF-MS. All four extracts reduced the viability of human M…

Fast one-step liquid chromatography determination of purine compounds in blood with photodiode array detector

2012

Influenza della tostatura e della preparazione del caffè sul contenuto di Ocratossina A determinata mediante HPLC-FD

2008

Analysis of sterols by high-performance liquid chromatography/mass spectrometry combined with chemometrics

2006

A newly developed high-performance liquid chromatography/mass spectrometry (HPLC/MS) method has been successfully used to analyze plasma concentrations of various phytosterols (cholestanol and beta-sitosterol) and cholesterol metabolites (desmosterol and lathosterol). This was based on an unusual solvent combination of water/methanol vs. methanol/acetone/n-hexane applied on a Purospher Star RP-18e (125 x 2 mm, 3 microm) column, which proved excellent for the separation, identification and quantification of plasma sterols. Simple solid-phase extraction preparation of plasma samples was performed, followed by the developed fast and robust HPLC separation. Results on four groups of people were…

HPLC-DAD-ESI-MS2analytical profile of extracts obtained from purple sweet potato after green ultrasound-assisted extraction

2016

International audience; Ultrasound pre-treatment (UAE) was applied to assist the extraction of valuable compounds (polyphenols (especially anthocyanins), and proteins) from purple sweet potato (PSP). Under optimum conditions (ultrasound time (40 min); supplementary hot extraction (80 °C) up to 120 min; pH: 2.5; ethanol concentration: 58%), the highest concentrations of polyphenols (3.877 mg/g), anthocyanins (0.293 mg/g), and proteins (0.753 mg/g) were found, with minimal specific energy consumption (8406 J/mg).Moreover, anthocyanin and non-anthocyanin polyphenols in PSP extract from optimized extraction temperature were identified using HPLC-DAD-ESI-MS2. The major identified anthocyanins we…

Moringa oleifera Leaf Powder as Functional Additive in Cookies to Protect SH-SY5Y Cells

2021

The aim of this work is the evaluation of the addition of Moringa leaf powder (MLP) in cookies in terms of antioxidant properties, dough processability and sensorial properties of the cookies. The total content of biophenols and flavonoids in MLP was detected and the identification of the bioactive molecules was performed by HPLC-ESI-TOF-MS measurements, before and after oven treatment at 180 ◦C for 20 min. After a preliminary evaluation of the MLP water soluble fraction (MLPsf) cytotoxicity, its protective effect against an oxidative injury induced in the SH-SY5Y cells was assessed. Data evidence that the bioactive molecules present in MLPsf are effective in preventing ROS production and i…

On the use of ionic liquids as mobile phase additives in high-performance liquid chromatography. A review.

2015

The popularity of ionic liquids (ILs) has grown during the last decades in several analytical separation techniques. Consequently, the number of reports devoted to the applications of ILs is still increasing. This review is focused on the use of ILs (mainly imidazolium-based associated to chloride and tetrafluoroborate) as mobile phase additives in high-performance liquid chromatography (HPLC). In this approach, ILs just function as salts, but keep several kinds of intermolecular interactions, which are useful for chromatographic separations. Both cation and anion can be adsorbed on the stationary phase, creating a bilayer. This gives rise to hydrophobic, electrostatic and other specific in…