Search results for "LC-DAD"
showing 10 items of 10 documents
HPLC-DAD profile of phenolic compounds and In vitro antioxidant activity of Ficus carica L. fruits from two Algerian varieties
2022
Ficus carica L., commonly known as the fig tree, is a plant belonging to the Moraceae family whose fruits are traditionally used for edible and therapeutic purposes. The study aimed to investigate the lyophilized aqueous extracts of two native Algerian fig varieties, azendjar (Az) and taamriouth (Ta), as a potential source of antioxidant compounds for possible use as ingredients in pharmaceuticals or nutraceuticals. The HPLC-DAD analysis revealed the presence of two phenolic acids (3,4-dihydroxybenzoic acid and vanillic acid) and two flavonoids (rutin and quercetin) at levels 3.67, 4.80, 84.16, and 6.87 µg/g respectively for Az variety extract, and 6.90, traces, 7.46 and 3.37 µg/g respectiv…
Biosynthesis of beauvericin and enniatins in vitro by wheat Fusarium species and natural grain contamination in an area of central Italy
2015
Contamination of wheat grain by beauvericin (BEA) and enniatins (ENs) is a global emerging mycotoxicological food problem. In this study, strains of Fusarium avenaceum (FA), Fusarium poae (FP), Fusarium equiseti and Fusarium sporotrichioides, all potential BEA and EN producers, isolated from 162 grain samples of durum and soft wheat harvested in 2009 and 2010 collected in an area of central Italy, were preliminarily screened for the presence of the esyn1 gene, encoding the multifunctional enzyme enniatin-synthetase for the detection of potential hexadepsipeptide-producing isolates. All positive isolates were tested for their ability to biosynthesize BEA and ENs in vitro. In addition, all wh…
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…
Science based calibration for the extraction of 'analyte-specific' HPLC-DAD chromatograms in environmental analysis
2010
Multivariate science based calibration (SBC) has been applied to the resolution of overlapped peaks in liquid chromatography with diode array detection (LC-DAD). Complex river water samples spiked with 11 pharmaceutical substances resulted in poorly resolved chromatograms containing additional peaks from interfering matrix compounds and a change in the background absorbance due to the mobile phase gradient. Applying the present multivariate approach it was possible to resolve all 11 analytes from overlapping peaks, obtaining linear calibration lines (R2 > 0.96). Recovery percentages on spiked samples ranged between 74.6 and 113.5%, which are quite satisfactory taking into account the low co…
Determination of meropenem in endotracheal tubes by in-tube solid phase microextraction coupled to capillary liquid chromatography with diode array d…
2017
Meropenem is a widely used antimicrobial for the treatment of infections associated with the use of invasive medical devices in intensive care unit patients. These treatments are not always effective, in fact, in-vitro studies have demonstrated the difficulty of antimicrobials to penetrate into the biofilm, however in-vivo studies of the effect of these compounds is a trend, mostly because of the complexity of pulmonary samples extracted from ETTs. Therefore, the objective of this study was to evaluate in-tube solid phase microextraction (in-tube SPME) coupled to capillary liquid chromatography (CapLC) with DAD to determine meropenem in Errs in order to estimate the penetration capability i…
Fast simultaneous determination of prominent polyphenols in vegetables and fruits by reversed phase liquid chromatography using a fused-core column
2015
A reversed-phase high-performance liquid chromatography method with photodiode array detection has been developed enabling the joint determination of 17 prominent flavonoids and phenolic acids in vegetables and fruits. A multi-segmented gradient program using a fused-core column for the separation of several phenolic classes (phenolic acids and flavonoids) has been optimised. The influence of extraction conditions (sample freeze-drying, ultrasound extraction, solvent composition and extraction time) has been also optimised using response surface methodology with tomato samples as a model. Complete recoveries (76-108%) were obtained for the phenolic compounds present in tomato. The developed…
Phytochemical profile and antioxidant properties of the edible and non-edible portions of black sapote (Diospyros digyna Jacq.)
2022
This study evaluated the phytochemical profile and antioxidative properties of the edible and non-edible portions of black sapote. The phytochemical analysis highlighted the presence of several bioactive compounds, differently distributed among peel, pulp and seeds. In particular, the peel resulted rich of flavan-3-ols and proanthocyanidins, whereas seeds contained high amount of organic acids, including ferulic, citric and sinapic acids. Concerning functional properties, both edible and non-edible portions showed a significant prevention of lipid peroxidation in a cell-based model. Moreover, the results suggested that the antioxidant protection involved both redox active properties and gen…
Polyphenol Characterization, Antioxidant and Skin Whitening Properties of Alnus cordata Stem Bark
2019
In this study, we investigated the phenolic composition of the crude extract (MeOH 80 %) of Alnus cordata (Loisel.) Duby stem bark (ACE) and its antioxidant and skin whitening properties. RP-LC-DAD analysis showed a high content of hydroxycinnamic acids (47.64 %), flavanones (26.74 %) and diarylheptanoids (17.69 %). Furthermore, ACE exhibited a dose-dependent antioxidant and free-radical scavenging activity, expressed as half-maximal inhibitory concentration (IC50 ): Oxygen radical absorbance capacity (ORAC, IC50 1.78 μg mL-1 )>Trolox equivalent antioxidant capacity (TEAC, IC50 3.47 μg mL-1 )>2,2-Diphenyl-1-picrylhydrazyl (DPPH, IC50 5.83 μg mL-1 )>β-carotene bleaching (IC50 11.58 μg mL-1 )…
Chemical Profile and Biological Activity of Cherimoya (Annona cherimola Mill.) and Atemoya (Annona atemoya) Leaves
2020
Annona cherimola (Cherimoya) and Annona atemoya (Atemoya) are tropical plants known for their edible fruit. Scientific data suggest that their leaves, used in traditional medicine in the form of teas or infusions without evidence of toxicity, contain several bioactive compounds. However, only Annona muricata among all the Annona species is currently used in the nutraceutical field, and its dried leaves are marketed for tea preparation. In this work, we explored the nutraceutical potential of Atemoya and Cherimoya leaves, by evaluating their chemical profile and functional properties. Phytochemical analyses showed large amounts of phenolic compounds, in particular proanthocyanidins, and iden…
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…