Search results for "DPPH"
showing 10 items of 137 documents
Chemical Profiling of Polyfloral Belgian Honey: Ellagic Acid and Pinocembrin as Antioxidants and Chemical Markers
2017
Chemical profiling of northern Belgian polyfloral honeys was performed to analyse their phenolic compound content (flavonoids and phenolic acids). First, samples were subjected to a standard analysis of their physicochemical properties, and then, the phenolic fraction was isolated and analysed using a HPLC/PAD method. All of the tested honeys showed a common and specific phenolic profile that could be the basis for the differentiation of polyfloral honeys of the Antwerp region from other polyfloral honeys. Chromatographic data indicated a high content of ellagic acid (9.13–13.66 mg/100 g honey), as well as the flavonoid pinocembrin (1.60–1.85 mg/100 g honey) in these honeys. Ellagic acid, a…
Kundmannia sicula (L.) DC: a rich source of germacrene D
2017
AbstractObjective: Kundmannia sicula is an herbaceous plant belonging to the family Apiaceae and is distributed in the Mediterranean coastal areas where it occurs in arid places. In this work, we have analysed the essential oil distilled from the aerial parts of K. sicula from Sicily (Italy) and its biological activity. Methods: GC-MS was used to analyze the chemical composition, whereas its antioxidant capacity and cytotoxicity on three human tumour cells (A375, MDA MB-231 and HCT 116) were evaluated by DPPH, ABTS, FRAP and MTT methods, respectively. Result: The essential oil resulted very rich of the sesquiterpene hydrocarbon germacrene D (81.2%). Moreover, the K. sicula oil displayed rel…
Antioxidant Properties of a Supercritical Fluid Extract of the Halophyte Mesembryanthemum nodiflorum L. from Sicilian Coasts: Nutraceutical and Cosme…
2020
The aim of this paper was to obtain different extracts from the aerial parts of Mesembryanthemum nodiflorum, comparing traditional extraction (using solvents with increasing polarity such as hexane, ethanol 80%, acetone 70% and water) with an eco-friendly technique (supercritical fluid extraction (SFE))
Comparative chemical composition, free radical-scavenging and cytotoxic properties of essential oils of six Stachys species from different regions of…
2009
Abstract The chemical composition of essential oils of six Stachys species, S. cretica L. ssp. vacillans Rech. fil., S. germanica L., S. hydrophila Boiss., S. nivea Labill., S. palustris L. and S. spinosa L., obtained by hydrodistillation, was studied by GC and GC–MS. All the oils have in common a great percentage of fatty acids and esters (24.2–58.5%) and a high amount of sesquiterpenes (16–35.9%), with the exception of the oil from S. palustris , which consisted mainly of carbonylic compounds (25.4%). The antioxidant activity by DPPH test and the antiproliferative activity on a series of human cancer cell lines (C32, amelanotic melanoma and ACHN, renal cell adenocarcinoma) were investigat…
Protective Effects of the Hydroethanolic Extract of Fridericia chica on Undifferentiated Human Neuroblastoma Cells Exposed to α-Zearalenol (α-ZEL) an…
2021
Fridericia chica (Bignoniaceae) is a traditional medicinal plant. The aim of this research was to determine the protective effects of the hydroethanolic extract from the F. chica leaves (HEFc) against the cytotoxicity of zearalenone (α-ZEL) and β-ZEL on SH-SY5Y cells. Free radical scavenging activity of HEFc was evaluated using the DPPH method. The cytotoxicity of both zearalenone metabolites and HEFc was examined using MTT test, as was the cytoprotective effects of the HEFc on cells treated with these mycotoxins. The chemical composition of HEFc was determined using UPLC-QTOF-MS/MS. HEFc elicited good DPPH radical scavenging activity following a concentration-dependent relationship. Cells …
High Throughput Screening for Bioactive Volatile Compounds and Polyphenols from Almond (Prunus amygdalus) Gum: Assessment of Their Antioxidant and An…
2016
This work was devoted to recover and identify bioactive polyphenols and volatile compounds from almond gum, which can be used as food additives and/or nutraceuticals. For this purpose, solvent extract was obtained after hydrodistillation of almond gum and the extracted volatiles were identified using gas chromatography-mass spectrometry (GC-MS). The major compounds were 9-octadecenoic acid (18.47%), 3-eicosene (17.04%), hexadecanoic acid (13.82%), benzyl salycilate (9.54%), 1-octadecene (7.28%), cetene (4.38%) and turmerone (3.2%). Subsequently, the antioxidant and antibacterial activities of the obtained extracts rich in polyphenols and volatile compounds were evaluated. Antioxidant activi…
Anti-inflammatory activity of erycristagallin, a pterocarpene from Erythrina mildbraedii.
2003
Erycristagallin, a pterocarpene isolated from Erythrina mildbraedii, was tested in vitro for its antioxidant properties on the stable 2,2-diphenyl-1-pycryl-hydrazyl (DPPH) free radical and on the arachidonic acid metabolism. In addition, erycristagallin was tested on different experimental models of inflammation, such as the acute and chronic inflammation induced by the application of 12-O-tetradecanoylphorbol 13-acetate (TPA) on mice and the phospholipase A(2)-induced mouse paw oedema test. In the carrageenan-induced mouse paw oedema test, the ethyl acetate extract obtained from E. mildbraedii showed anti-inflammatory activity, and erycristagallin was isolated as the active principle. In v…
Negative-pressure cavitation coupled with aqueous two-phase extraction and enrichment of flavonoids and stilbenes from the pigeon pea leaves and the …
2015
Abstract An efficient extraction method, negative-pressure cavitation coupled with aqueous two-phase extraction (NPC-ATPE), was developed to simultaneously extract and enrich flavonoids and stilbenes from pigeon pea leaves. The main bioactive compounds, cajaninstilbene acid (CSA), longistyline C (LLC), pinostrobin (PI) and pinostrobin chalcone (PIC) were chosen as target compounds. The extraction conditions were optimized using central composite design combined with response surface methodology. The optimized conditions were: concentration of (NH 4 ) 2 SO 4 21% (w/w), concentration of ethanol 23% (w/w) and temperature 30 °C, negative pressure −0.06 MPa, extraction time 30 min and the liquid…
Nanocarriers for antioxidant resveratrol: formulation approach, vesicle self-assembly and stability evaluation.
2013
In this work we studied various nanoformulations of resveratrol in phospholipid vesicles. Conventional phophatidylcholine liposomes were prepared and characterized in parallel with PEVs (Penetration Enhancer-containing Vesicles) obtained by adding one of eight selected amphiphilic penetration enhancers (PEs; 0.2% w/v; HLB range 1-16) to the composition. All vesicles were around 100 nm, negatively charged (∼-30 mV) and able to incorporate resveratrol in good yields (>74%). The structure and the lamellar self-organization of the vesicles were investigated by Transmission Electron Microscopy (TEM) and Small and Wide Angle X-ray Scattering (SWAXS). These analyses showed that the lamellarity of …
Negative pressure cavitation-microwave assisted preparation of extract of Pyrola incarnata Fisch. rich in hyperin, 2'-O-galloylhyperin and chimaphili…
2013
Abstract A novel and effective extraction method, namely negative pressure cavitation-microwave assisted extraction technique (NMAE), was developed for the preparation of extracts of Pyrola incarnata Fisch., which are rich in the main constituents hyperin, 2′-O-galloylhyperin and chimaphilin. Single factor experiments and Box–Behnken design (BBD) were combined with a response surface methodology to examine factors affecting extraction. Maximum extraction yields of hyperin, 2′-O-galloylhyperin and chimaphilin (1.339 ± 0.029, 4.831 ± 0.117 and 0.329 ± 0.011 mg/g, respectively) were achieved under the following optimised conditions: 700 W microwave power, 50 °C extraction temperature, 30:1 mL/…