Search results for "LAV"
showing 10 items of 3985 documents
Reactions of Flavonoids with o‑Quinones Interfere with the Spectrophotometric Assay of Tyrosinase Activity
2016
Flavonoids are important food components with antioxidant properties and many of them have been described as tyrosinase inhibitors. Oxidation of quercetin, kaempferol, morin, catechin, and naringenin by mushroom tyrosinase and their influence on the oxidation of l-dopa and l-tyrosine was studied. Reaction rates measured spectrophotometrically and by oxygen consumption differed substantially. All tested flavonoids reacted with 4-tert-butyl-o-benzoquinone and/or 4-methyl-o-benzoquinone, although at different rates. These reactions generated products whose UV-vis spectra either overlapped or did not overlap with the spectrum of dopachrome. They therefore strongly influence the kinetic analysis…
Effect of (−)-epigallocatechin gallate at different pH conditions on enteric viruses.
2017
Epigallocatechin gallate (EGCG), a flavonoid from green tea, is said to have extensive antimicrobial activity in a wide range of food spoilage or pathogenic fungi, yeast and bacteria. In this work, the antiviral activity of EGCG was assessed against hepatitis A virus (HAV) and murine norovirus (MNV), a human norovirus surrogate, at different temperatures, contact times and pH conditions by cell-culture methods. EGCG was effective in reducing the titers of HAV and MNV in a dose-dependent manner at neutral pH and 25 and 37 °C, while no effect was reported at 4 °C. HAV and MNV infectivity was completely removed after overnight treatment with EGCG at 2.5 mg/mL at 37 °C. Furthermore, results als…
Neurodegenerative diseases: Might citrus flavonoids play a protective role?
2016
Neurodegenerative diseases (ND) result from the gradual and progressive degeneration of the structure and function of the central nervous system or the peripheral nervous system or both. They are characterized by deterioration of neurons and/or myelin sheath, disruption of sensory information transmission and loss of movement control. There is no effective treatment for ND, and the drugs currently marketed are symptom-oriented, albeit with several side effects. Within the past decades, several natural remedies have gained attention as potential neuroprotective drugs. Moreover, an increasing number of studies have suggested that dietary intake of vegetables and fruits can prevent or delay th…
Impact of ultrasound extraction parameters on the antioxidant properties of Moringa oleifera leaves
2020
Recently, much interest has been focused on Moringa oleifera L., a highly versatile and sustainable plant. In addition to its nutritional properties, numerous bioactive compounds have been identified in M. oleifera leaves, for which healthy properties have been reported. In the present research, the impact of ultrasound-assisted extraction (UAE) on the recovery of the bioactive compounds from leaves was investigated. Firstly, an experimental design approach has been used to highlight the influence of some extraction parameters (solvent, solvent/dry leaves ratio, temperature, time) on phenol compound recovery and antioxidant activity. Solvent composition was the most influential factor
Screening for Latent Tuberculosis Infection among Students of Healthcare Professions and Postgraduates of the Faculty of Medicine of the University o…
2017
Introduction and objective: Italy is a country with a low incidence of tuberculosis and in the last fifty years the annual number of TB cases decreased from 12,247 to 4,418, showing a reduction of approximately 64% in the number of cases and 71% in incidence. Despite of this encouraging trend, in the last years the epidemiology of tuberculosis changed and today it is a re-emerging infectious. The aim of this study is to measure the prevalence of positivity to tuberculosis infection (latent TB) in students, without any obvious manifestation of disease, attending degree courses of the health care professions and postgraduate medical courses of the School of Medicine of the University of Paler…
Identification of Phlogacantholide C as a Novel ADAM10 Enhancer from Traditional Chinese Medicinal Plants
2016
Background: Alzheimer’s disease is one of the most prevalent dementias in the elderly population with increasing numbers of patients. One pivotal hallmark of this disorder is the deposition of protein aggregates stemming from neurotoxic amyloid-beta peptides. Synthesis of those peptides has been efficiently prevented in AD model mice by activation of an enzyme called alpha-secretase. Therefore, drugs with the capability to increase the expression of this enzyme, named ADAM10, have been suggested as a valuable therapeutic medication. Methods: We investigated 69 substances from a drug library derived from traditional Chinese medicine by luciferase reporter assay in human neuronal cells for th…
Associations between dietary polyphenols and type 2 diabetes in a cross-sectional analysis of the PREDIMED-Plus Trial: role of body mass index and sex
2019
Overweight and obesity are important risk factors for type 2 diabetes (T2D). Moving towards healthier diets, namely, diets rich in bioactive compounds, could decrease the odds of suffering T2D. However, those individuals with high body mass index (BMI) may have altered absorption or metabolism of some nutrients and dietary components, including polyphenols. Therefore, we aimed to assess whether high intakes of some classes of polyphenols are associated with T2D in a population with metabolic syndrome and how these associations depend on BMI and sex. This baseline cross-sectional analysis includes 6633 participants from the PREDIMED-Plus trial. Polyphenol intakes were calculated from food fr…
Human-Driven Microbiological Contamination of Benthic and Hyporheic Sediments of an Intermittent Peri-Urban River Assessed from MST and 16S rRNA Gene…
2017
International audience; Rivers are often challenged by fecal contaminations. The barrier effect of sediments against fecal bacteria was investigated through the use of a microbial source tracking (MST) toolbox, and by Next Generation Sequencing (NGS) of V5-V6 16S rRNA gene (rrs) sequences. Non-metric multi-dimensional scaling analysis of V5-V6 16S rRNA gene sequences differentiated bacteriomes according to their compartment of origin i.e., surface water against benthic and hyporheic sediments. Classification of these reads showed the most prevalent operating taxonomic units (OTU) to be allocated to Flavobacterium and Aquabacterium. Relative numbers of Gaiella, Haliangium, and Thermoleophilu…
Polyphenols: Potential Use in the Prevention and Treatment of Cardiovascular Diseases
2018
Background: Polyphenols are bioactive compounds that can be found mostly in foods like fruits, cereals, vegetables, dry legumes, chocolate and beverages such as coffee, tea and wine. They are extensively used in the prevention and treatment of cardiovascular disease (CVD) providing protection against many chronic illnesses. Their effects on human health depend on the amount consumed and on their bioavailability. Many studies have demonstrated that polyphenols have also good effects on the vascular system by lowering blood pressure, improving endothelial function, increasing antioxidant defences, inhibiting platelet aggregation and low-density lipoprotein oxidation, and reducing inflammator…
Using food comfortability to compare food's sensory characteristics expectations of elderly people with or without oral health problems
2017
Food consumption is by far the most important point where food's organoleptic properties can be perceived and can elicit sensory pleasure. Ageing is often accompanied by oral impairments. Those impairments may impact food perception by changing texture perception and the release of flavor components, which have a significant impact on food acceptability. The present study aimed at evaluating the impact of oral health on the perception of food comfortability in an elderly population. This was achieved by asking elderly people with a good oral health and elderly people with poor oral health to rate six cereal products and six meat products using a food comfortability questionnaire. Thirty-sev…