Search results for "Phenol"
showing 10 items of 2273 documents
Chemical composition and microencapsulation suitability of sumac (Rhus coriaria L.) fruit extract
2021
Sumac (Rhus coriaria L.), a spice obtained by grinding whole sumac berries, is a complex natural product with a plethora of biological activities that can be favorably explored in nutraceutical and pharmaceutical fields. Sicilian sumac is herein chemically investigated by means of a combined NMR/HR MS-based profiling. A hydroalcoholic extract was prepared and its complexity unraveled following fractionation in an alcoholic and an aqueous fraction. The 1H-NMR spectrum of this latter fraction was dominated by the signals of gallic acid and its derivatives, whereas HR MS and HR MS/MS analyses highlighted the diversity in malic acid derivatives. Gallotannins and galloyl flavonol glycosides with…
Sicilian pistachio (Pistacia vera L.) nut inhibits expression and release of inflammatory mediators and reverts the increase of paracellular permeabi…
2014
Background Dietary approaches to control inflammatory bowel diseases (IBD) may include proanthocyanidin-rich foods. Our previous research showed that a hydrophilic extract from Sicilian pistachio nut (HPE) contains sub- stantial amounts of proanthocyanidins and possesses anti- inflammatory activities. Purpose We studied the effects of HPE and of its poly- meric proanthocyanidin fraction (PPF) in a cell model that simulated some conditions of IBD, consisting of interleukin (IL)-1b-stimulated Caco-2 cells. Methods HPE was prepared by Pistacia vera L. nuts, and PPF was isolated from HPE by adsorbance chromatogra- phy. Proanthocyanidins were quantified as anthocyanidins after acidic hydrolysis.…
Alcohol-Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts
2015
Abstract The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent‐free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst is synthesized by grafting 4‐(4‐(4‐hydroxyphenylimino)cyclohexa‐2,5dienylideneamino)phenol and silver nanoparticles onto the surface of moderately crystalline titanium dioxide. The titanium dioxide‐based composite was first extensively characterized and then employed in the catalytic oxidati…
Chemopreventive and Anticancer Role of Resveratrol against Oral Squamous Cell Carcinoma
2023
Oral squamous cell carcinoma (OSCC) is one of the most prevailing and aggressive head and neck cancers, featuring high morbidity and mortality. The available conventional treatments suffer from several adverse effects and are often inefficient in terms of their survival rates. Thus, seeking novel therapeutic agents and adjuvants is of the utmost importance for modern society. Natural polyphenolic compounds have recently emerged as promising chemopreventive and anticancer agents. Specifically, the natural compound resveratrol (RSV) has recently gained momentum for this purpose. RSV is useful for treating OSCC due to its antiproliferative, antimetastatic, and proapoptotic effects. Additionall…
Destroying the Shield of Cancer Stem Cells: Natural Compounds as Promising Players in Cancer Therapy
2022
In a scenario where eco-sustainability and a reduction in chemotherapeutic drug waste are certainly a prerogative to safeguard the biosphere, the use of natural products (NPs) represents an alternative therapeutic approach to counteract cancer diseases. The presence of a heterogeneous cancer stem cell (CSC) population within a tumor bulk is related to disease recurrence and therapy resistance. For this reason, CSC targeting presents a promising strategy for hampering cancer recurrence. Increasing evidence shows that NPs can inhibit crucial signaling pathways involved in the maintenance of CSC stemness and sensitize CSCs to standard chemotherapeutic treatments. Moreover, their limited toxici…
Nutritional properties and plausible benefits of Pearl millet (Pennisetum glaucum) on bone metabolism and osteoimmunology : a mini-review
2020
Bone is a hard connective tissue that undergoes a systematic renewal. This highly dynamic organ is made up of four different types of cells, however, bone formation is commonly attributed to osteoblasts and bone resorption to osteoclasts. Bone tissue formation occurs during embryonic development and in certain post-birth pathological conditions. The immune system could influence the functions of bone cells, and the crosstalk between hematopoietic, immune, and bone cells is known as osteoimmunology. Indeed, cytokines produced by immune cells, including TNF-α and IL-6, are critically implicated in bone pathogenesis. It is well established that diet plays an important role in bone health and f…
Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Indust…
2021
Red grape Nero d’Avola cultivar grape pomace powder (GPP) was applied during fresh ovine cheese production in order to increase polyphenol content. Before cheeses were produced, the bacteria of a freeze-dried commercial starter culture were isolated and tested in vitro against GPP. Two dominant strains, both resistant to GPP, were identified. Thestarter culture was inoculated in pasteurized ewe’s milk and the curd was divided into two bulks, one added with 1% (w/w) GPP and another one GPP-free. GPP did not influence the starter culture development, since lactic acid bacteria (LAB) counts were 109 CFU/g in both cheeses at 30 d. To exclude the interference of indigenous LAB, the pasteurized m…
Rifampicin is not an inhibitor of tyrosinase
2022
Rifampicin has been previously described as an inhibitor of tyrosinase (Chai et al., Int. J. Biol. Macromol. 102 (2017) 425–430). However, rifampicin contains a p-diphenol group and compounds with such a moiety have been shown before to reduce tyrosinase-generated o-quinones. Rifampicin also shows strong absorption in a region completely overlapping with the visible absorption band of dopachrome, the oxidation product of L-tyrosine and L-dopa, whose concentration is measured spectrophotometrically in the standard enzymatic assay to monitor the activity of tyrosinase. We have demonstrated that rifampicin is also rapidly oxidized by o-quinones generated from catechols by tyrosinase or by trea…
THE ANTIOXIDANT PROPERTIES OF PHENOLIC MOLECULES IN RELATIONSHIP WITH THE pH OF ENVIRONMENT REACTION
2011
THE ANTIOXIDANT PROPERTIES OF PHENOLIC MOLECULES IN RELATIONSHIP WITH THE pH OF ENVIRONMENT REACTION Some epidemiological evidence suggests beneficial effects on human health from a diet rich in fruit, vegetables and certain types of beverages such as tea and wine (1,2). These compounds do not have nutritive properties but they have a functional role in the human organism. Some studies have investigated the effect of pH on the antioxidant properties of polyphenols (3,4) and have reported that the pH-dependent behaviour is related to hydroxyl deprotonation. However, these studies did not compare the antioxidant activity of various classes of polyphenols and did not take into account the acid…
ASPETTI FISIOLOGICI E QUALITATIVI NEL PROCESSO DI MATURAZIONE DI ALCUNE CULTIVAR DI PESCO (Prunus persica L. Batsch) IN POST-RACCOLTA ED IN IV GAMMA
2014
L’importanza della peschicoltura siciliana è evidenziata dalla percentuale dell’ 8% con cui concorre la superficie peschicola italiana e da un ampio assortimento varietale, connotato dalla rilevante presenza di genotipi autoctoni, che godono di un notevole successo commerciale. In tale contesto, per le loro pregevoli caratteristiche organolettiche, legate all’aroma e al flavour persistenti, si collocano le produzioni peschicole dei Monti Sicani, commercializzate con il termine di “Pesca di Bivona” e le cv della “Pesca di Leonforte”, oggetto della presente trattazione e in precedenza di altre ricerche (Caruso et al., 1983; Baratta et al., 1986; Marchese et al., 2006; Montevecchi et al., 2012…