Search results for " phenolic compound"
showing 10 items of 25 documents
Ecological function of phenolic compounds from mediterranean fucoid algae and seagrasses: An overview on the genus Cystoseira sensu lato and Posidoni…
2020
Biodiversity is undergoing rapid and worrying changes, partially driven by anthropogenic activities. Human impacts and climate change (e.g., increasing temperature and ocean acidification), which act at different spatial scales, represent the most serious threats to biodiversity and ecosystem structure and function. In the Mediterranean Sea, complex systems such as fucoid algae and seagrasses, characterized by a high associated biodiversity, are regularly exposed to natural and anthropogenic pressures. These systems, particularly sensitive to a variety of stressors, evolved several physiological and biochemical traits as a response to the different pressures which they are subjected to. For…
The effect of abrasive pretreatment on the drying kinetics and phenolic compounds in goji berries ( Lycium barbarum L.)
2020
The paper investigated the effect of a physical surface abrasion of goji berries on drying kinetics and the evolution of phenolic compounds at 323, 333, and 343 K. A diffusion model was developed to describe the drying process. The effective diffusion coefficient estimated by the model ranged from 7.5 × 10–9 to 4.2 × 10–8 m2/s for cylinder and 2.0 × 10–9 to 1.15 × 10–8 m2/s for sphere for untreated samples (UTR). Higher values were found for treated samples (TR) (from 2.50 × 10–8 to 1.20 × 10–7 m2/s for cylinder and 8.0 × 10–9 to 2.70 × 10–8 m2/s for sphere). For the UTR samples, the values of activation energy were found to be 79.5 and 80.8 kJ/mol, respectively, in the cylinder and sphere …
Influence of pre-fermentative addition of aqueous solution tannins extracted from oak wood (Quercus petraea) on the composition of Grillo wines
2021
AbstractIn this research, the chemical characterization of fixed and volatile compounds of two different tannins in aqueous solution (Pratiko® L-Harvest and L-Fruit) extracted from oak wood, has been studied. The influence of the above tannins, at different concentrations, on the alcoholic fermentation kinetics and on the composition and sensorial characteristics of a white wine were then evaluated. The wines added tannins in aqueous solution compared to control wines showed significant differences in fixed compounds (colloids, polyphenols and ellagitannins) and volatile compounds (phenolic aldehydes, volatile phenols, furanic and piranic compounds). The differences of aqueous solution tann…
Quality and volatile compounds in red wine at different degrees of dealcoholization by membrane process
2019
This study investigated the effect of different degrees of dealcoholization on volatile compounds, phenols and sensory characteristics of red wine (cv. Montepulciano d’Abruzzo). The wine with an initial alcohol content of 13.2% v/v was partially dealcoholized by membrane process with a decrease of alcohol degree as follows: − 4.9; − 6.3; − 7.8, − 9.2 and − 10.5% v/v. Osmotic distillation has proved effective in preserving a satisfactory odorous profile, as samples with an alcohol residue of 8.3% v/v (− 4.9%) and 6.9% v/v (− 6.3%) showed good esters retention: more than 84% and 82%, respectively. Similarly, colour and taste, evaluated by flavonoids and phenolic compounds, remained almost unc…
Quantitative evaluation of the phenolic profile in fruits of six avocado (Persea americana) cultivars by ultra-high-performance liquid chromatography…
2016
The phenolic profiles of six varieties of avocado (Persea americana) grown in Sicily were investigated. The ultra-high-performance liquid chromatography-heated electrospray-mass spectrometry method was developed to determine qualitative and quantitative changes in fruits at two different ripening stage. Nineteen individual phenolic compounds were detected in avocado pulp extracts. Gallic acid, sinapinic acid, vanillin, p-coumaric acid, and gentisic acid were present only in ripe fruits. On the contrary, epicatechin decreased with fruit ripening, whereas protocatechuic acid, 4-hydroxybenzoic acid, chlorogenic acid, and benzoic acid were relatively stable or exhibited erratic changes with fru…
Investigation on the influence of spray-drying technology on the quality of Sicilian Nero d’Avola wines
2018
The purpose of the present work was to find a correlation between microencapsulation technology applied to wines and the resulting quality of the wine itself in terms of volatile composition and phenolic profile. To this aim, samples of Nero d'Avola wines produced in Sicily (Italy) were investigated in order to: i) elucidate the aromatic composition by means of HSâSPME coupled with GCâMS; ii) assess the polyphenolic content by UHPLC mass spectrometry; iii) compare the results obtained from both the screenings with those relative to the same wines that had previously been subjected to spray-drying. The results showed a marked reductionThe results here obtained evidenced a marked reductio…
Anti-/pro-oxidant concentration-dependent activity of natural phenolic compounds in bio-polyesters
2017
Polylactic acid (PLA) is a biodegradable bio-based polyester of increasing industrial interest because of its unique properties, such as low toxicity, bio- and eco-compatibility. Indeed, PLA is a suitable material for several “green” applications in different fields, among other food packaging, textile fibres and biomedical devices [1]. PLA performances, in terms of durability, are limited by several chemical aging mechanisms, such as thermal decomposition, hydrolysis, photo-oxidation, natural weathering and thermo-oxidation at high temperature [2]. Therefore, to avoid the decay of its physical and mechanical properties, the addition of anti-oxidants and/or light stabilizers is imperative. …
Metabolite profile and in vitro activities of Phagnalon saxatile (L.) Cass. relevant to treatment of Alzheimer’s disease
2009
The present study describes for the first time the in vitro properties (inhibition of NO production and anticholinesterase) of Phagnalon saxatile (L.) Cass. (Asteraceae). The methanolic extract showed antioxidant activity that was measured by DPPH assay and beta-carotene bleaching test. The same extract inhibited NO production in the murine monocytic macrophage cell line RAW 264.7. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition was assessed by modifications of Ellman's method. Purification of the MeOH extract of P. saxatile allowed the isolation of phenolic compounds. Among them, the compounds that most effectively inhibited lipopolysaccharide-induced NO production …
Alternariol-induced cytotoxicity in Caco-2 cells. Protective effect of the phenolic fraction from virgin olive oil.
2014
The extra virgin olive oil (EVOO) has been associated to antioxidant effects. The mycotoxin alternariol (AOH) can contaminate olives. The aims of this work were to determine the cytotoxic effects and reactive oxygen species (ROS) produced by AOH, tyrosol and oleuropein (two polyphenols of olive oil) and a real EVOO extract in Caco-2 cells. The MTT assay and the ROS production by the H2-DCFDA probe were used. Results demonstrated that AOH reduces cellular proliferation depending on concentration, whereas tyrosol and oleuropein did not (12.5-100 μM). The combination of AOH + oleuropein (50 μM) increased cell proliferation (24%) whereas, AOH + tyrosol decreased (47%) it. Besides, AOH increased…
Ultrasound-assisted green solvent extraction of high-added value compounds from microalgae Nannochloropsis spp.
2015
Abstract The aim of this work was to investigate ultrasound (US)-assisted green solvent extraction of valuable compounds from the microalgae Nannochloropsis spp. Individual green solvents (water, ethanol (EtOH), dimethyl sulfoxide (DMSO)) and binary mixture of solvents (water-DMSO and water-EtOH) were used for the extraction procedures. Maximum total phenolic compounds yield ( Y p ≈ 0.33) was obtained after US pre-treatment ( W = 400 W, 15 min), being almost 5-folds higher compared to that found for the untreated samples and aqueous extraction ( Y p ≈ 0.06). The highest yield of total chlorophylls ( Y c ≈ 0.043) was obtained after US ( W = 400 W, 7.5 min), being more than 9-folds highe…