Search results for "DPPH"
showing 10 items of 137 documents
Invazīvo augu (Lupinus polyphyllus, Impatiens glandulifera, Echinocystis lobate) bioloģiski aktīvo vielu grupas un to izmantošanas potenciāls bioekon…
2022
Invazīvās augu sugas var veicināt ar ekosistēmu funkcionēšanu saistītas problēmas, radot ekonomiskus zaudējumus, kaitējumu cilvēka veselībai un samazinot rekreācijas resursu kvalitāti. Tās raksturo strauja un agresīva izplatīšanās, nomācot endēmiskās sugas. Pilnīgai invazīvo augu biomasas izmantošanai ir nepieciešams atrast ilgtspējīgus, bioekonomikā balstītus pārstrādes risinājumus, kas ļautu iegūt komponentus vai produktus ar augstu pievienoto vērtību. Darbā tika apskatītas dažādas daudzlapu lupīnas, puķu spriganes un adatainā dzeloņgurķa augu daļas. Augos tika noteikts kopējais polifenolu daudzums, novērtēta antiradikālā aktivitāte (DPPH), un lupīnās atrodamie alkaloīdi (GC-MS). Augstākā…
Direct NMR evidence for the dissociation of sulfur-dioxide-bound acetaldehyde under acidic conditions: Impact on wines oxidative stability
2021
Abstract SO2 reaction with electrophilic species present in wine, including in particular carbonyl compounds, is responsible for the reduction of its protective effect during wine aging. In the present study, direct 1H NMR profiling used to monitor the reactivity of SO2 with acetaldehyde under wine-like oxidation conditions. The dissociation of acetaldehyde bound SO2 was evidenced suggesting that released free SO2 can further act as an antioxidant. EPR and DPPH assays showed an increasing antioxidant capacity of wine with the increase in the concentration of acetaldehyde sulfonate. The presence of acetaldehyde sulfonate in wines was correlated with the overall antioxidant activity of wines.…
Contribution to the molecular study of the oxidative stability of white wines of Burgundy
2019
In order to understand and control the aging of wines, particularly white wines, it is necessary to deepen our knowledge about the physico-chemical mechanisms of oxidation related to oxygenation processes. For this, it is important to have tools to quantify the antioxidant capacity of white wines, and to identify the compoiunds involved, in order to anticipate the aging ability of a wine.In this study, analyzes of the antioxidant capacity by DPPH and Electron Paramagnetic Resonance (EPR) were carried out on a large number of wines during aging and from several vintages, in parallel with metabolomic analyzes, mainly carried out by Liquid Chromatography Coupled to Mass Spectrometry (UPLC-Q-TO…
Antioxidant Activity and Release Kinetics of Caffeic and p-Coumaric Acids from Hydrocolloid-Based Active Films for Healthy Packaged Food
2017
International audience; Sustainable hydrocolloid-based films containing natural antioxidants, caffeic and p-coumaric acids at different concentrations of 0.5%, 1%, 5%, and 10% w/w of polymers, were designed for packing fatty foods. Antioxidant activities and kinetics for all film formulations were assessed using radical scavenging activity (DPPH), reducing power, and iron chelating ability. Release kinetics of the antioxidants from the films into a food simulant (96% ethanol) were analyzed. The intermolecular interactions between antioxidants and polymers chains were assessed by Fourier transform infrared attenuated total reflectance (FTIR-ATR) and related to the film properties. Antioxidan…
Investigating the Antiproliferative and Antioxidant Properties of Pancratium maritimum L. (Amaryllidaceae) Stems, Flowers, Bulbs, and Fruits Extracts
2018
Pancratium maritimumstems, flowers, bulbs, and fruits extracts were investigated for their antiproliferative and antioxidant properties. Total phenols and total flavonoids were also determined. Thein vitroantiproliferative activity was tested against seven cancer cell lines such as C32, HeLa, MDA-MB-231, PC3, A549, MCF-7, and LNCaP by using SRB assay. Interesting results were obtained with stems ethanol extract (ET1) against C32 cells (IC50of 27.1μg/mL) and fruits aqueous extract (AQ) against MCF-7 cell line (IC50of 36.5μg/mL). To define the antioxidant activity, four tests such as DPPH, ABTS FRAP, andβ-carotene bleaching tests were used.The most promising ABTS scavenging capacity was obser…
Chemical composition, antioxidant and anticholinesterase activity of the essential oil of algerian cachrys sicula L
2021
In this work, in order to explore a new Algerian medicinal plant used in traditional medicine, the essential oil of the leaves of Cachrys sicula L. (Apiaceae) collected from Algeria, obtained by hydrodistillation, was analyzed by GC/MS. Thirty-two compounds were identified accounting for 98.6% of the total oil, which is characterized by a high content of monoterpene hydrocarbons (74.8%). The main constituents of the essential oil were β-pinene (17.9%), sabinene (17.8%), myrcene (12%), and α-pinene (11.4%). In vitro antioxidant activity of the essential oil was assayed by three methods, namely ABTS•+, metal chelating, and DPPH• assays. The antioxidant activity of the oil was higher in the AB…
In Vitro Antioxidant Activity and In Vivo Topical Efficacy of Lipid Nanoparticles Co-Loading Idebenone and Tocopheryl Acetate
2019
Idebenone (IDE) is a strong antioxidant that has been proposed for the treatment of skin disorders, including skin ageing. Unfavorable physico-chemical properties make IDE a poor skin permeant where effectiveness could be improved by its loading into suitable delivery systems such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC). In this work, we designed novel IDE-loaded NLC containing tocopheryl acetate (VitE) as a liquid component to obtain a synergic effect between IDE and VitE. The resulting NLC showed small particle sizes (24&ndash
Species-Specific Antioxidant Power and Bioactive Properties of the Extracts Obtained from Wild Mediterranean Calendula Spp. (Asteraceae)
2019
In this study we focused on four taxa of the genus Calendula (C. maritima, C. suffruticosa subsp. fulgida, C. arvensis, and the hybrid between the first two ones), collected in Mediterranean area (Sicily). Six extracts for each species were obtained using solvents with increasing polarity (hexane, ethanol 80%, acetone 70%, and water) and through extraction by supercritical fluids (SFE). It has been observed that the solvent with the highest extraction efficiency was ethanol 80% for all species. However, SFE extracts showed high antioxidant activity comparable to the ethanol 80% extract (polyphenol, DPPH, and reducing power method). These findings were confirmed by in vitro analysis (MTT ass…
Phytochemical profile of three Ballota species essential oils and evaluation of the effects on human cancer cells
2017
Three Ballota species, Ballota undulata, Ballota saxatilis and Ballota nigra ssp. foetida, were investigated for their cytotoxicity against two human cancer cells, hepatoma HepG2 cell line and breast cancer MCF-7 cell line, and for their antioxidant activity. The chemical composition of essential oils was studied by GC and GC–MS. Sesquiterpenes were the main constituents. The most antiproliferative essential oil against HepG2 cells was B. undulata with a percentage of inhibition of 81.36 ± 3.54 at a concentration of 100 μg/mL, while against MCF-7 cells essential oil from B. saxatilis was the most active with a percentage of inhibition of 24.18 ± 1.13 at a concentration of 100 μg/mL. The ant…
Phytochemical Profile and Antioxidant Activity of the Aerial Part Extracts from Matthiola incana subsp. rupestris and subsp . pulchella ( Brassicacea…
2021
As part of a project aimed at investigating the Matthiola taxa endemic to Sicily (Italy), this study focused on Matthiola incana, an edible species used in the traditional medicine of various countries. Herein, the characterization of phenolic and volatile compounds, the antioxidant capacity in vitro (1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power and Fe2+ chelating activity assays) and the toxicity test (Artemia salina lethality bioassay) of the hydroalcoholic extracts from the aerial parts of M. incana subsp. rupestris from Mt. Pellegrino (Palermo) and Mt. Erice (Trapani), and of M. incana subsp. pulchella are reported. The results are compared with those previously shown for M. inc…