We have tested the hypothesis that the antidiabetic biguanide metformin can be used to manipulate the threshold for stress-induced senescence (SIS), thus accelerating the onset of cancer-protective cellular senescence in response to oncogenic stimuli. Using senescence-prone murine embryonic fibroblasts (MEFs), we assessed whether metformin treatment modified the senescence phenotype that is activated in response to DNA damaging inducers. Metformin significantly enhanced the number of MEFs entering a senescent stage in response to doxorubicin, an anthracycline that induces cell senescence by activating DNA damage signaling pathways (e.
View Article and Find Full Text PDFPolyphenols have become a subject of intense research because of their perceived beneficial effects on health due to their anticarcinogenic, antiatherogenic, anti-inflammatory, and antimicrobial activities. It is well known that olives and their derivatives are rich in phenolic substances with pharmaceutical properties, some of which exert important antioxidant effects. The characterization and quantification of their polyphenol composition is one of the first steps to be taken in any evaluation of the putative contribution of the olive to human health.
View Article and Find Full Text PDFRejuvenation Res
February 2012
The epithelial-to-mesenchymal transition (EMT) genetic program is a molecular convergence point in the life-threatening progression of organ fibrosis and cancer toward organ failure and metastasis, respectively. Here, we employed the EMT process as a functional screen for testing crude natural extracts for accelerated drug development in fibrosis and cancer. Because extra virgin olive oil (EVOO) (i.
View Article and Find Full Text PDFIn the present work, a simple and rapid method for the extraction of phenolic compounds from olive leaves, using microwave-assisted extraction (MAE) technique, has been developed. The experimental variables that affect the MAE process, such as the solvent type and composition, microwave temperature, and extraction time, were optimized using a univariate method. The obtained extracts were analyzed by using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS(2)) to prove the MAE extraction efficiency.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2012
The phenolic fraction of a commercial cranberry syrup, which is purported to have good properties for the prevention of urinary diseases, has been thoroughly characterized using HPLC-DAD-TOF-MS. A study of its antibacterial activity has also been carried out. For this purpose a new HPLC-DAD-TOF-MS method using negative and positive ionization modes was developed and it was thus possible to identify 34 different compounds, nine of which have been tentatively characterized for the first time in cranberry syrup.
View Article and Find Full Text PDFPhenolic compounds in extra virgin olive oil (EVOO) have been associated with beneficial effects for health. Indeed, these compounds exert strong antiproliferative effects on many pathological processes, which has stimulated chemical characterization of the large quantities of wastes generated during olive oil production. In this investigation, the potential of byproducts generated during storage of EVOO as a natural source of antioxidant compounds has been evaluated using solid-liquid and liquid-liquid extraction processes followed by rapid resolution liquid chromatography (RRLC) coupled to electrospray time-of-flight and ion trap mass spectrometry (TOF/IT-MS).
View Article and Find Full Text PDFA new liquid chromatography methodology coupled to a diode array detector and a time-of-flight mass spectrometer has been developed for the simultaneous determination of phenolic compounds and saponins in quinoa (Chenopodium quinoa Willd). This method has allowed the simultaneous determination of these two families of compounds with the same analytical method for the first time. A fused-core column C18 has been used, and the analysis has been performed in less than 27 min.
View Article and Find Full Text PDFIn the current work, a molecularly imprinted polymer (MIP) has been synthesised and used to enable the extraction of a naturally-occurring antioxidant from complex media. More specifically, we describe the first example of a caffeic acid (CA) MIP which has been synthesised in the form of well-defined polymer microspheres, and its use for the extraction of CA from fruit juice sample. The CA MIP was synthesised by precipitation polymerisation using 4-vinylpyridine as functional monomer, divinylbenzene-80 as crosslinker and acetonitrile:toluene (75/25, v/v) as porogen.
View Article and Find Full Text PDFIn the present work, a comparative study between two environmentally friendly and selective extraction techniques, such as supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE) have been carried out focusing in the bioactive phenolic compounds present in Rosmarinus officinalis. For the analysis of the SFE and PLE extracts, a new methodology for qualitative characterization has been developed, based on the use of reversed-phase high-performance liquid chromatography (RP-HPLC), equipped with two different detection systems coupled in series: diode array detector (DAD) and time of flight mass spectrometry (TOF-MS) detector connected via an electrospray ionization interface (ESI). The use of a small particle size C(18) column (1.
View Article and Find Full Text PDFThe phenolic compounds present in seven samples of olive fruits were analysed by a rapid and resolutive LC-ESI-TOF MS method. All samples were collected during the normal picking period for olive oil production, in central and south Tunisia, and were obtained from the Oueslati variety cultivated in different olive growing areas. In the Tunisian samples, 22 compounds have been characterised by LC-ESI-TOF MS analysis.
View Article and Find Full Text PDFThe health-promoting properties of common wheat (Triticum aestivum L.) have been largely attributed to the presence of unique phytochemicals of whole grains. The aim of this study was to profile the phenolic content of 16 old and 6 modern Italian wheat varieties, cropped in the same location and growing season.
View Article and Find Full Text PDFNowadays there is considerable interest in the consumption of alternative crops as potential recipes for gluten-free products production. Therefore, the use of buckwheat for the production of gluten-free pasta has been investigated in the present study. RP-HPLC-ESI-TOF-MS has been applied for the separation and characterization of free and bound phenolic compounds in buckwheat flour and buckwheat spaghetti.
View Article and Find Full Text PDFIn this contribution, the capabilities of pressurized liquid extraction (PLE) using food-grade solvents, such as water and ethanol, to obtain antioxidant extracts rich on polyphenolic compounds from olive leaves are studied. Different extraction conditions were tested, and the PLE obtained extracts were characterized in vitro according to their antioxidant capacity (using the DPPH radical scavenging and the TEAC assays) and total phenols amounts. The most active extracts were obtained with hot pressurized water at 200 °C (EC(50) 18.
View Article and Find Full Text PDFRooibos (Aspalathus linearis) is a rich source of polyphenols and used to make a mild-tasting tea containing no caffeine, is low in tannins compared to green or black teas, and has antioxidant and antimutagenic/antitumoral properties. In vivo results show that rooibos has beneficial effects upon the lipid profile by decreasing serum triglycerides and cholesterol. In this sense, we have developed a simple and rapid method to separate and characterize simultaneously the polyphenolic compounds in aqueous and ethanolic rooibos extracts using high-performance liquid chromatography coupled to electrospray ionization time-of-flight mass spectrometry (HPLC-ESI-TOF-MS) and ion trap multiple mass spectrometry (HPLC-ESI-IT-MS(2)).
View Article and Find Full Text PDFInt J Oncol
June 2011
Characterization of the molecular function of complex phenols naturally present in extra virgin olive oil (EVOO) against the HER2-gene amplified JIMT-1 cell line, a unique breast cancer model that inherently exhibits cross-resistance to multiple HER1/2-targeted drugs including trastuzumab, gefitinib, erlotinib and lapatinib, may underscore innovative cancer molecules with novel therapeutic targets because they should efficiently circumvent de novo resistance to HER1/2 inhibitors in order to elicit tumoricidal effects. We identified pivotal signaling pathways associated with the efficacy of crude phenolic extracts (PEs) obtained from 14 monovarietals of Spanish EVOOs. i) MTT-based cell viability and HPLC coupled to time-of-flight (TOF) mass spectrometry assays revealed that anti-cancer activity of EVOO PEs positively correlated with the phenolic index (i.
View Article and Find Full Text PDFA sensitive CE-ESI-MS analytical method for the identification of buckwheat antioxidants has been developed. CE and ESI-TOF parameters (e.g.
View Article and Find Full Text PDFIntroduction: Cistaceae is a large family of shrubs widely spread over the Mediterranean area. It includes Helianthemum, Halimium and Cistus genus. Cistus genus contains approximately 20 species distributed in three subgenus.
View Article and Find Full Text PDFJ Chromatogr A
February 2011
A new analytical approach based on gas chromatography coupled to atmospheric pressure chemical ionization-time of flight mass spectrometry was evaluated for its applicability for the analysis of phenolic compounds from extra-virgin olive oil. Both chromatographic and MS parameters were optimized in order to improve the sensitivity and to maximize the number of phenolic compounds detected. We performed a complete analytical validation of the method with respect to its linearity, sensitivity, precision, accuracy and possible matrix effects.
View Article and Find Full Text PDFThe incidence of obesity and related metabolic diseases is increasing globally. Current medical treatments often fail to halt the progress of such disturbances, and plant-derived polyphenols are increasingly being investigated as a possible way to provide safe and effective complementary therapy. Rooibos (Aspalathus linearis) is a rich source of polyphenols without caloric and/or stimulant components.
View Article and Find Full Text PDFThis paper reviews the phenolic-compound-extraction systems used to analyse fruit and vegetable samples over the last 10 years. Phenolic compounds are naturally occurring antioxidants, usually found in fruits and vegetables. Sample preparation for analytical studies is necessary to determine the polyphenolic composition in these matrices.
View Article and Find Full Text PDFThe consumption of tomatoes and tomato products has been associated with a reduction in the risk of contracting some types of cancer and other chronic diseases. These beneficial properties may be attributed to the presence of key metabolites and the interactions among them. We have developed and validated an analytical method for the comprehensive profiling of semi-polar metabolites in the methanol extract of three cultivars of raw tomatoes (Daniela, Raf and Rambo) grown in Almería, in south-east Spain.
View Article and Find Full Text PDFThe aim of this work was to develop a rapid resolution liquid chromatography coupled to electrospray ionization time-of-flight mass spectrometry (RRLC-ESI-TOF-MS) method followed by tetrazolium salt (MTT)-based cell viability assays for qualitative and quantitative classification of extra virgin olive oil (EVOO) varieties by phenolic and other polar compound contents as well as for rapid characterization of putative cytotoxic activities against human cancer cells. Five different Spanish EVOO varieties were analyzed, and RRLC-ESI-TOF-MS method was applied for qualitative and quantitative identification of most important phenolic compounds. We finally employed MTT-based cell viability protocol to assess the effects of crude EVOO phenolic extracts (PEs) on the metabolic status of cultured SKBR3 human breast cancer cells.
View Article and Find Full Text PDFJ Agric Food Chem
August 2010
The phenolic fraction of a monovarietal extra virgin olive oil (EVOO) from Olea europaea L. var. Cornezuelo was studied by the hyphenated HPLC-DAD-SPE-NMR/MS techniques.
View Article and Find Full Text PDFIn this study, a CE-MS method has been developed to carry out the qualitative characterization of a lemon verbena (Lippia citriodora) extract for the first time. The CE and ESI-MS parameters were optimized with respect to resolution, analysis time and peak shape in order to maximize the number of compounds detected and the sensitivity of their determination. The use of two different MS analyzers, TOF-MS and IT-MS, enabled the tentative identification of the major components of this extract.
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