Search results for "Polyphenol"
showing 10 items of 514 documents
Biosorption of green and black tea polyphenols into Saccharomyces cerevisiae improves their bioaccessibility
2015
Infusions of green tea (GT) and black tea (BT) and the use of Saccharomyces cerevisiae as a natural matrix were employed to check the impact of biosorption on the possible fate of tea polyphenols in the gastrointestinal tract in terms of bioaccessibility and total antioxidant capacity (TEAC and ORAC assays). The maximum biosorption yields obtained were 47.61 ± 11.57 and 99.68 ± 5.25 mg/g from GT and BT infusions, respectively. A significant increase (p < 0.05) in the recovery of phenolic compounds was shown after in vitro digestion. The bioaccessible fractions generally exhibited higher antioxidant capacities in both tea infusions and suspensions of S. cerevisiae versus non-digested samples…
Modulation of biotransformation and elimination systems by BM-21, an aqueous ethanolic extract from Thalassia testudinum, and thalassiolin B on human…
2012
Abstract BM-21 is an extract obtained from Thalassia testudinum marine plant with pharmacological properties. The effects of BM-21 and thalassiolin B (TB), its main component, on enzyme and transport proteins involved in drug metabolism and excretion in human cultured hepatocytes were evaluated. Cells were exposed for 48 h to sub-cytotoxic concentrations of BM-21 or TB. Effects on P450 isoforms revealed significant reductions of CYP1A2, 3A4 and 2D6 activities (up to 56%, 66% and 44% inhibition, respectively) after exposition to BM-21, no changes on CYP2A6 and 2C9 activities. TB produced a concentration-dependent reduction of all P450 activities. In addition, a decrease in total UGT and UGT2…
Nopal Cactus (Opuntia ficus-indica) as a Source of Bioactive Compounds for Nutrition, Health and Disease
2014
Opuntia ficus-indica, commonly referred to as prickly pear or nopal cactus, is a dicotyledonous angiosperm plant. It belongs to the Cactaceae family and is characterized by its remarkable adaptation to arid and semi-arid climates in tropical and subtropical regions of the globe. In the last decade, compelling evidence for the nutritional and health benefit potential of this cactus has been provided by academic scientists and private companies. Notably, its rich composition in polyphenols, vitamins, polyunsaturated fatty acids and amino acids has been highlighted through the use of a large panel of extraction methods. The identified natural cactus compounds and derivatives were shown to be e…
Water as a Solvent of Election for Obtaining Oleuropein-Rich Extracts from Olive (Olea europaea) Leaves
2021
Leaves from Olea europaea represent one of the main by-products of the olive oil industry, containing a plethora of bioactive compounds with several promising activities for human health. An organic solvent-free extraction method was developed for the recovery of olive leaf phenols, which obtained an extract containing oleuropein in high amounts. A comparison of various extraction media is reported, together with the total phenolic content, DPPH (2,2-Diphenyl-1-picrylhydrazyl) content, ORAC (oxygen radical absorbance capacity), and polyphenol oxidase activity of the corresponding extracts. The polyphenol profiles and content of the most representative extracts have also been studied. Extrac…
Multispectral fluorescence sensitivity to acidic and polyphenolic changes in Chardonnay wines – The case study of malolactic fermentation
2022
International audience; In this study, stationary and time-resolvedfluorescence signatures, were statistically and chemometrically analyzed among three typologies of Chardonnay wines (A, B and C) with the objectives to evaluate their sensitivity to acidic and polyphenolic changes. For that purpose, a dataset was built using Excitation Emission Matrices of fluorescence (N = 103) decomposed by a Parallel Factor Analysis (PARAFAC), andfluorescence decays (N = 22), mathematically fitted, using the conventional exponential modeling and the phasor plot representation. Wine PARAFAC component C4 coupledwith its phasor plot g and s values enable the description of malolactic fermentation (MLF) occur…
PD-1/PD-L1 Checkpoints and Resveratrol: A Controversial New Way for a Therapeutic Strategy
2021
Simple Summary Over the last decade, immunotherapies using antibodies targeting the programmed cell death 1 (PD-1) checkpoint or its ligand, programmed death ligand 1 (PD-L1), have emerged as promising therapeutic strategies against cancer. However, some current limitations include a relatively low rate of “responders”, the high cost of the treatment, and a rare risk of hyper-progression. Currently, the main challenge is, therefore, to improve these therapies, for instance, by using combined approaches. Here, we summarize the accumulating evidence that resveratrol (RSV) plays a role in the modulation of the PD-1/PD-L1 axis in cancer cells, suggesting the potential of therapeutic strategies …
Green Extraction of Polyphenols from Waste Bentonite to Produce Functional Antioxidant Excipients for Cosmetic and Pharmaceutical Purposes: A Waste-t…
2022
In an ever-growing perspective of circular economy, the development of conscious, sustainable and environmental-friendly strategies to recycle the waste products is the key point. The scope of this work was to validate the waste bentonite from the grape processing industries as a precious matrix to extract polyphenols by applying a waste-to-market approach aimed at producing novel functional excipients. The waste bentonite was recovered after the fining process and opportunely pre-treated. Subsequently, both the freeze dried and the so-called “wet” bentonites were subjected to maceration. PEG200 and Propylene Glycol were selected as solvents due to their ability to dissolve poly…
Full inhibition of enzymatic browning in the presence of thiol-functionalised silica nanomaterial
2018
[EN] Darkening processed fruits and vegetables is caused mainly by enzymatic browning through polyphenol oxidase (PPO) action. Accordingly, we explored the potential of four silica-based materials (MCM-41 nanometric size, MCM-41 micrometric size, UVM-7 and aerosil), non-functionalised and functionalised with thiol groups, to inhibit PPO activity in the model system and apple juice. All materials showed relevant performance when immobilising and inhibiting PPO in model systems, and support topology is a main factor for enzyme immobilisation and inhibition. Thiol-containing silica UVM7-SH showed the greatest inactivation, and similar browning values to those obtained by acidification. The enz…
Influence of the functionalisation of mesoporous silica material UVM-7 on polyphenol oxidase enzyme capture and enzymatic browning
2020
Polyphenol oxidase (PPO), also known as tyrosinase and catechol oxidase, is the enzyme responsible for enzymatic browning in foods. It causes undesirable organoleptic, nutritional and colour changes. Here, we report the preparation of five nanomaterials and a study of their ability to modulate PPO enzyme activity. The materials consist of UVM-7 supports (a mesoporous silica material) modified with diverse functional groups (i.e. amine, carboxylic acid, isocyanate, alkane and pyridine). We also studied the PPO immobilisation capability of the materials. All the materials, except the carboxylic acid functionalised one, offer high PPO loading capabilities and the immobilisation speed increases…
EFFECT OF ADDING SOLID AND MOLTEN CHOCOLATE ON THE POLYPHENOL CONTENT, CHEMICAL, TEXTURAL, MICROBIOLOGICAL AND SENSORY ASPECTS OF PECORINO SICILIANO …
In this project we used two specific food products, which are typically Sicilian, Pecorino Siciliano cheese and Modica chocolate, that have unique texture and taste. “Chocolate cheese” is produced with the aim of increasing the consumption of cheese especially among children, targeting the purpose of improving public health. In this research we investigated chocolate cheese including solid and molten chocolate in three levels of 5%, 10% and 15% at four ripening times (T0 = fresh, T1 = 2 weeks, T2 = 4 weeks and T3 = 6 weeks). The results showed that the addition of chocolate significantly (p ≤ 0.05) decreased the pH, ash and protein content of the Pecorino Siciliano cheese, whereas it had no…