Search results for "PRESSURE"
showing 10 items of 4493 documents
Phytochemical profile and antioxidative properties of Plinia trunciflora fruits: A new source of nutraceuticals.
2020
Abstract This study evaluated the polyphenol profile and the antioxidative properties of Plinia trunciflora (O. Berg) Kausel fruits. Folin-Ciocalteau and pH-jumping methods indicated that these berries are a major source of antioxidant polyphenols (1201.05 mg GAE/100 g FW), particularly anthocyanins. HPLC-DAD-ESI-MS/MS analysis identified cyanidine glycosides as the main components. Flavon-3-ols and hydrolysable-tannins were also found. CAA assay showed that extracts of P. trunciflora fruits prevent lipid peroxidation in HepG2 cells with higher efficacy than other colourful fruits (CAA50 935.25 mg FW/mL cell medium). Moreover, our results suggested that the observed antioxidant protection i…
Antioxidant Activity of All-trans-retinol in Homogeneous Solution and in Phosphatidylcholine Liposomes
1993
A kinetic quantification of the lipoperoxyl radical-scavenging activity of all-trans-retinol has been carried out in homogeneous solution, when radicals were produced from the oxidation of methyl linoleate in methanol, initiated by the lipid-soluble 2,2′-azobis (2,4-dimethyl-valeronitrile) (AMVN) as well as in a soybean phosphatidylcholine membrane model, in which peroxidation was induced either by AMVN or the hydrophylic 2,2′-azobis(2-amidinopropane)hydrochloride (AAPH). The physical microenvironment contributes to the determination of antioxidant efficiency of all-trans-retinol. In homogeneous solution the kinetic constant kinh is 3.5 × 105 M-1 s-1 and appears of the same order of magnitu…
Salmon (Salmo salar) side streams as a bioresource to obtain potential antioxidant peptides after applying pressurized liquid extraction (PLE)
2021
The pressurized liquid extraction (PLE) technique was used to obtain protein extracts with antioxidant capacity from salmon muscle remains, heads, viscera, skin, and tailfins. A protein recovery percentage ≈28% was obtained for all samples except for viscera, which was ≈92%. These values represented an increase of 1.5–4.8-fold compared to stirring extraction (control). Different SDS-PAGE profiles in control and PLE extracts revealed that extraction conditions affected the protein molecular weight distribution of the obtained extracts. Both TEAC (Trolox equivalent antioxidant capacity) and ORAC (oxygen radical antioxidant capacity) assays showed an outstanding antioxidant activity for viscer…
Polyphenols pattern and correlation with antioxidant activities of berries extracts from four different populations of SicilianSambucus nigraL.
2014
Sambucus nigra L. (Caprifoliaceae) is wide spread in temperate and sub-tropical zones. The consumption of its berries has been associated with health benefits especially for its high content of natural antioxidants such as polyphenols, in particular anthocyanins. In this work we investigated the polyphenolic composition and the in vitro antioxidant activities (ABTS, DPPH, BCB and FRAP-ferrozine (FRAP-FZ) assays) of S. nigra berries, collected in four different Sicilian areas (Italy). Elderberries are considered one of the fruits with highest anthocyanins content, the amount of phenolic compounds, other than anthocyanins, is approximately 1.5 times greater than the latter. The LC–MS analyses…
Extraction of polyphenols in Himanthalia elongata and determination by high performance liquid chromatography with diode array detector prior to its …
2016
Abstract Several studies have demonstrated the antioxidant capacity of seaweeds, which can be used for the development of biopharmaceuticals with extensive medical application. Antioxidant therapies appear to attenuate the organic deterioration originated by an excessive oxidative stress, which could prevent the harmful effects of various injuries such as ischemia-reperfusion (I/R) among others. Marine brown seaweeds play a significant role, as they are the only organisms on earth producing phlorotannins, which are polyphenols that exhibit important biological activity. To ensure obtaining an extract with the greatest antioxidant activity, some variables that affect the extraction of polyph…
Accelerated Solvent Extraction and Pulsed Electric Fields for Valorization of Rainbow Trout (Oncorhynchus mykiss) and Sole (Dover sole) By-Products: …
2021
Fishery by-products are rich in biologically active substances and the use of green and efficient extraction methods to recover these high-added-value compounds is of particular importance. In this study, head, skin and viscera of rainbow trout and sole were used as the target matrices and accelerated solvent extraction (ASE) (45–55 °C, 15 min, pH 5.2–6.8, 103.4 bars) and pulsed electric fields (PEF) (1–3 kV/cm, 123–300 kJ/kg, 15–24 h) were applied as extraction technologies. The results showed that ASE and PEF significantly increased the protein extract efficiency of the fish by-products (p < 0.05) by up to 80%. SDS-PAGE results showed that ASE and PEF treatments changed the molecular size…
Ultrasonically-Assisted and Conventional Extraction from Erodium Glaucophyllum Roots Using Ethanol:Water Mixtures: Phenolic Characterization, Antioxi…
2020
The paper presents experimental results concerning the ultrasonically-assisted extraction of bioactive compounds from Erodium glaucophyllum roots. A comparison with conventional methodology is presented, and thereby the phytochemical composition and the antioxidant and anti-inflammatory activities of extracts are evaluated. The phenolic profile of Erodium extracts was analyzed by TOF&ndash
Betacyanins as phenol antioxidants. Chemistry and mechanistic aspects of the lipoperoxyl radical-scavenging activity in solution and liposomes.
2009
Reaction kinetics of betanin and its aglycone betanidin towards peroxyl radicals generated from the azo-initiated oxidation of methyl linoleate in methanol, and of a heterogeneous aqueous/soybean phosphatidylcholine liposomal system, were studied by monitoring formation of linoleic acid hydroperoxides and consumption of the pigments. Betanin was a weak retarder in methanol, and an effective chain breaking antioxidant in the liposomal model, indicating that kinetic solvent effects and partition in lipid bilayers may affect its activity. Betanidin behaved as a chain terminating antioxidant in both models. Kinetic parameters characterizing peroxyl radical-scavenging activity showed that betani…
Anxiety level and decision-making among Norwegian top-class soccer referees
2013
The purpose of this study was to examine the level of anxiety experienced by Norwegian top-class soccer referees while officiating, and to predict the level of anxiety according to refereeing level and perceived refereeing competence. Also investigated were referees' perceptions of how crowd noise and disturbance from players and/or coaches, failure (i.e. mistakes) in refereeing, and aggressive behaviour by players and/or coaches influence their decision-making when officiating. A total of 83 (response rate: 84.7%) referees (73 men and 10 women) aged 20–46 years (mean = 33.2 years) completed our questionnaire using SurveyXact, a web-based program for conducting electronic questionnaires. Th…
Influence of dopexamine on hemodynamics, intramucosal pH, and regulators of the macrocirculation and microcirculation in patients undergoing abdomina…
2000
Abstract Objective: To investigate whether dopexamine hydrochloride beneficially influences splanchnic perfusion and regulators of the macrocirculation and microcirculation in patients undergoing surgery of the abdominal aorta. Design: Prospective, blinded, and randomized study. Setting: University-affiliated hospital. Participants: Twenty patients undergoing elective abdominal aortic surgery. Interventions: The patients were randomized to one of two groups. In the dopexamine group (DOP, n = 10), dopexamine, 1 μg/kg/min, was started before surgery and continued for 24 hours. In the control group (COG, n = 10), patients received saline solution as placebo. Extensive hemodynamic monitoring wa…