iridoids and 4-hydroxyphenylethanol

The Mediterranean diet (MD) is a combination of foods mainly rich in antioxidants and anti-inflammatory nutrients that have been shown to have many health-enhancing effects. Extra-virgin olive oil (EVOO) is an important component of the MD. The importance of EVOO can be attributed to phenolic compounds, represented by phenolic alcohols, hydroxytyrosol, and tyrosol, and to secoiridoids, which include oleocanthal, oleacein, oleuropein, and ligstroside (along with the aglycone and glycosidic derivatives of the latter two). Each secoiridoid has been studied and characterized, and their effects on human health have been documented by several studies. Secoiridoids have antioxidant, anti-inflammatory, and anti-proliferative properties and, therefore, exhibit anti-cancer activity. This review summarizes the most recent findings regarding the pharmacological properties, molecular targets, and action mechanisms of secoiridoids, focusing attention on their preventive and anti-cancer activities. It provides a critical analysis of preclinical, in vitro and in vivo, studies of these natural bioactive compounds used as agents against various human cancers. The prospects for their possible use in human cancer prevention and treatment is also discussed.

Topics: Aldehydes; Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Antioxidants; Cyclopentane Monoterpenes; Diet, Mediterranean; Glucosides; Humans; Iridoid Glucosides; Iridoids; Neoplasms; Olive Oil; Phenols; Phenylethyl Alcohol; Pyrans

Loss of β-cell function and β-cell death is the key feature of type 2 diabetes mellitus (T2DM). One hypothesis for the mechanism of this feature is amyloid formation by the human islet amyloid polypeptide (hIAPP). Despite the global prevalence of T2DM, there are no therapeutic strategies for the treatment of or prevention of amylin amyloidosis. Clinical trials and population studies indicate the healthy virtues of the Mediterranean diet, especially the extra virgin olive oil (EVOO) found in this diet. This oil is enriched in phenolic compounds shown to be effective against several aging and lifestyle diseases. Oleuropein (Ole), one of the most abundant polyphenols in EVOO, has been reported to be anti-diabetic. Some of Ole's main derivative have attracted our interest due to their multi-targetted effects, including interference with amyloid aggregation path. However, the structure-function relationship of Ole and its metabolites in T2DM are not yet clear. We report here a broad biophysical approach and cell biology techniques that enabled us to characterize the different molecular mechanisms by which tyrosol (TYR), hydroxytyrosol (HT), oleuropein (Ole) and oleuropein aglycone (OleA) modulate the hIAPP fibrillation in vitro and their effects on cell cytotoxicity. The OleA formed by enolic acid and hydroxytyrosol moiety was found to be more active than the Ole and HT at low micromolar concentrations. We further demonstrated that OleA inhibit the cytotoxicity induced by hIAPP aggregates by protecting more the cell membrane from permeabilization and then from death. These findings highlight the benefits of consuming EVOO and the great potential of its polyphenols, mainly OleA. Moreover, they support the possibility to validate and optimize the possible pharmacological use of EVOO polyphenols for T2DM prevention and therapy and also for many other amyloid related diseases.

Topics: Acetates; Cell Survival; Cyclopentane Monoterpenes; Diabetes Mellitus, Type 2; Diet, Mediterranean; Fluorescence; Humans; Inhibitory Concentration 50; Iridoid Glucosides; Iridoids; Islet Amyloid Polypeptide; Islets of Langerhans; Microscopy, Atomic Force; Olive Oil; Phenylethyl Alcohol; Phospholipids; Pyrans; Structure-Activity Relationship

The huge interest in the health-related properties of foods to improve health has brought about the development of sensitive analytical methods for the characterization of natural products with functional ingredients. Greek olive leaves and drupes constitute a valuable source of biophenols with functional properties. A novel ultra-high-performance liquid chromatography-quadrupole time of flight tandem mass spectrometry (UHPLC-QTOF-MS) analytical method was developed to identify biophenols through target and suspect screening in Greek olive leaves and drupes of the varieties: Koroneiki, Throumbolia, Konservolia, Koutsourelia, Kalamon, Petrolia, Amigdalolia, Megaritiki, Mastoeidis, Agouromanakolia, Agrilia, Adramitiani and Kolovi. The method's performance was evaluated using the target compounds: oleuropein, tyrosol and hydroxytyrosol. The analytes demonstrated satisfactory recovery efficiency for both leaves (85.9-90.5%) and drupes (89.7-92.5%). Limits of detection (LODs) were relatively low over the range 0.038 (oleuropein)-0.046 (hydroxytyrosol) and 0.037 (oleuropein)-0.048 (hydroxytyrosol) for leaves and drupes, respectively For leaves, the precision limit ranged between 4.7 and 5.8% for intra-day and between 5.8 and 6.5% for inter-day experiments, and for drupes, it ranged between 3.8 and 5.2% for intra-day and between 5.1 and 6.2% for inter-day experiments, establishing the good precision of the method. The regression coefficient (r

Topics: Chromatography, High Pressure Liquid; Geography; Greece; Hot Temperature; Iridoid Glucosides; Iridoids; Limit of Detection; Metabolomics; Olea; Phenylethyl Alcohol; Plant Extracts; Plant Leaves; Reproducibility of Results; Seasons; Seeds; Tandem Mass Spectrometry; Time Factors

Major phenolic compounds from olive oil (ArOH-EVOO), oleuropein (Ole), tyrosol (Tyr), and

Topics: Cell Death; Cell Line, Tumor; Chromatography, Liquid; Coumaric Acids; Humans; Hydrogen Peroxide; Iridoid Glucosides; Iridoids; Neuroprotection; Neuroprotective Agents; Oxidation-Reduction; Phenylethyl Alcohol; Propionates; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

Tyrosol, hydroxytyrosol and oleuropein are among the major phenolic compounds in fruits, leaves and oils from Olea europaea L. These natural antioxidants molecules revealed several beneficial effects on human health, but a low bioavailability and accessibility to targeted site. Liposomes are drug/nutraceutical delivery carriers, used for driving bioactive molecules to desired target tissues, decreasing potential side effects and protecting the encapsulated molecule from enzymatic metabolic processes. In this study, zwitterionic liposomes containing tyrosol, hydroxytyrosol and oleuropein were synthesized and characterized for their size and surface charge. Particular attention was devoted to the determination of encapsulation efficiency (EE%), quantifying the loaded Tyr, HTyr and Ole amount, by using three different techniques: direct UV spectrophotometry, High Performance Liquid Chromatography and Trolox Equivalent Antioxidant Capacity assay. The results revealed higher EE% for oleuropein. Cyto-toxicity and cyto-compatibility of liposomes were also tested on human chondrocyte cells.

Topics: Acetates; Antioxidants; Catechols; Cells, Cultured; Chondrocytes; Dietary Supplements; Drug Delivery Systems; Humans; Iridoid Glucosides; Iridoids; Liposomes; Olea; Phenylethyl Alcohol

Acrylamide and phenolic compounds on both fresh and cooked olives were monitored by HPLC/MS-MS and reversed-phase-HPLC methods along different procedures: elaboration process, high hydrostatic pressure (HHP), cooking treatment and bioavailability evaluation. Acrylamide was not detected during the elaboration process and after HHP treatment. Hydroxytyrosol, tyrosol, oleuropein and verbascoside were the most important phenols after HHP treatment. The frying and baking processes on olives enhanced the formation of acrylamide and a significant reduction in the phenolic compounds. The frying process produced lower acrylamide concentration and less reduction of phenolic compounds than the baking process, while in the gastrointestinal digestion these compounds were slightly reduced if compared to the initial stage. As a conclusion, the best way to ingest high quantities of phenols and reduce acrylamide consumption is by ingesting the olives when they are fresh. In case the olives need to be cooked, specific time and temperature conditions shall be applied.

Topics: Acrylamide; Chromatography, High Pressure Liquid; Chromatography, Reverse-Phase; Cooking; Hydrostatic Pressure; Iridoid Glucosides; Iridoids; Olea; Olive Oil; Phenols; Phenylethyl Alcohol; Tandem Mass Spectrometry

Polyphenols are constituents of all higher plants. However, their biosynthesis is often induced when plants are exposed to abiotic stresses, such as drought. The aim of the present work was to determine the phenolic status in the roots of olive trees grown under water deficit conditions. The results revealed that roots of water-stressed plants had a higher content of total phenols. The main compound detected in well-watered olive tree roots was verbascoside. Oleuropein was established as the predominant phenolic compound of water-stressed plants. The oleuropein/verbascoside ratio varied between 0.31 and 6.02 in well-watered and water-stressed plants respectively, which could be a useful indicator of drought tolerance in olive trees. Furthermore, this study is the first to provide experimental evidence showing that luteolin-7-rutinoside, luteolin-7-glucoside and apigenin-7-glucoside were the dominant flavonoid glucosides in olive tree roots and showed the most significant variations under water stress.

Topics: Antioxidants; Apigenin; Droughts; Flavonoids; Glucosides; Iridoid Glucosides; Iridoids; Olea; Phenol; Phenols; Phenylethyl Alcohol; Plant Extracts; Plant Leaves; Plant Roots; Polyphenols; Spectrophotometry, Ultraviolet; Stress, Physiological; Water

Olives and olive oil, a key food type of the Mediterranean diets, are packed with various important polyphenols including oleuropein (OLE), hydroxytyrosol (HTY) and tyrosol (TYR). OLE and HTY are highly powerful antioxidants and play a prime role in the therapeutics of free radical-related diseases. Their molecular stabilities and antioxidant properties can be improved by cyclodextrin (CD) encapsulation. Here, we present a systematic investigation on the inclusion complexes of β-CD-TYR (1), β-CD-HTY (2) and β-CD-OLE (3) by combined single-crystal structure determination, DFT complete-geometry optimization and DPPH antioxidant assay. X-ray analysis and DFT calculation reveal the preference of inclusion geometry with deep protrusion of the aromatic ring moieties of TYR, HTY and OLE from the β-CD O6-H-side, and the common host-guest stabilization scheme via intermolecular O-H⋯O hydrogen bonding interactions. No polyphenol OH group is shielded in the β-CD cavity, in contrast to the structures of β-CD-tea catechins complexes. The established host-guest O-H⋯O hydrogen bonds help to elevate antioxidant capacities of the olive polyphenols upon β-CD encapsulation. The order of antioxidant activity 2 >3 ≫ 1 based on the DPPH measurement is in fair agreement with their relative thermodynamic stabilities derived from DFT calculation.

Topics: beta-Cyclodextrins; Crystallography, X-Ray; Free Radical Scavengers; Hydrogen Bonding; Iridoid Glucosides; Iridoids; Models, Chemical; Molecular Structure; Phenylethyl Alcohol; Quantum Theory; Structure-Activity Relationship; Thermodynamics

In the present study, the aerial parts of the Laperrine olive (Olea europaea subsp. Laperrinei) are subjected to acid extraction and the chemical composition of the extracts is determined by HPLC-DAD. The main compounds found in all of extracts are: hydroxytyrosol (30.45%), tyrosol (0.69%), oleuropein (32.76%), ferrulic acid (17.77%), quercetin (31.57%) and hesperetin (6.90%).The extracts obtained from the leafy stems of Laperrine olive tree are tested on the moth Ephestia kuehniella flour. Their administration by inhalation of newly exuviated chrysalises extends the duration of nymphalid development and disturbs the exuviated adults reproduction, by reducing the period in which the eggs are being laid. Thus, compared to the control insects, the number of eggs laid by treated females is significantly reduced after the treatment by extracts. Besides, the administration of different extracts of adult butterflies has a premature mortality effect.

Topics: Animals; Chromatography, High Pressure Liquid; Female; Hesperidin; Insecticides; Iridoid Glucosides; Iridoids; Larva; Moths; Olea; Phenylethyl Alcohol; Plant Extracts; Plant Leaves; Quercetin

Olive leaf extract is characterized by a high content of polyphenols (oleuropein, hydroxytyrosol and their derivatives), which is associated with its therapeutic properties. The objective of the present research was to evaluate the antifungal activity of olive leaf extract against Candida albicans ATCC 10231 and C. dubliniensis CBS 7987 strains. Minimum inhibitory concentrations (MIC) of the extract were determined by several in vitro assays. The extract showed a concentration depended effect on the viability of C. albicans with MIC value of 46.875 mg mL-1 and C. dubliniensis with MIC value 62.5 mg mL-1. Most sensitive methods for testing the antifungal effect of the extracts were the trypan blue exclusion method and fluorescent dye exclusion method while MIC could not be determined by the method according to the EUCAST recommendation suggesting that herbal preparations contain compounds that may interfere with this susceptibility testing. The fluorescent dye exclusion method was also used for the assessment of morphological changes in the nuclei of treated cells. According to the obtained results, olive leaf extract is less effective against the tested strains than hydroxytyrosol, an olive plant constituent tested in our previous study.

Topics: Anti-Bacterial Agents; Antifungal Agents; Antioxidants; Candida; Candida albicans; Cell Nucleus; Cell Nucleus Shape; Chromatography, High Pressure Liquid; Coloring Agents; Fluorescent Dyes; Iridoid Glucosides; Iridoids; Microbial Sensitivity Tests; Olea; Phenylethyl Alcohol; Plant Extracts; Plant Leaves; Trypan Blue

Potato, tomato, eggplant and pumpkin were deep fried, sautéed and boiled in Mediterranean extra virgin olive oil (EVOO), water, and a water/oil mixture (W/O). We determined the contents of fat, moisture, total phenols (TPC) and eighteen phenolic compounds, as well as antioxidant capacity in the raw vegetables and compared these with contents measured after cooking. Deep frying and sautéing led to increased fat contents and TPC, whereas both types of boiling (in water and W/O) reduced the same. The presence of EVOO in cooking increased the phenolics identified in the raw foods as oleuropein, pinoresinol, hydroxytyrosol and tyrosol, and the contents of vegetable phenolics such as chlorogenic acid and rutin. All the cooking methods conserved or increased the antioxidant capacity measured by DPPH, FRAP and ABTS. Multivariate analyses showed that each cooked vegetable developed specific phenolic and antioxidant activity profiles resulting from the characteristics of the raw vegetables and the cooking techniques.

Topics: Antioxidants; Benzothiazoles; Chlorogenic Acid; Chromatography, High Pressure Liquid; Cluster Analysis; Cooking; Cucurbita; Dietary Fats; Furans; Iridoid Glucosides; Iridoids; Lignans; Multivariate Analysis; Olive Oil; Phenols; Phenylethyl Alcohol; Rutin; Solanum lycopersicum; Solanum melongena; Solanum tuberosum; Sulfonic Acids; Vegetables

Hydroxytyrosol, tyrosol, and oleuropein, the main phenols present in extra virgin olive oil, have been reported to exert several biochemical and pharmacological effects. Here, we investigated the short-term effects of these compounds on lipid synthesis in primary-cultured rat-liver cells. Hydroxytyrosol, tyrosol and oleuropein inhibited both de novo fatty acid and cholesterol syntheses without an effect on cell viability. The inhibitory effect of individual compounds was already evident within 2 h of 25 μM phenol addition to the hepatocytes. The degree of cholesterogenesis reduction was similar for all phenol treatments (-25/30%), while fatty acid synthesis showed the following order of inhibition: hydroxytyrosol (-49%) = oleuropein (-48%) > tyrosol (-30%). A phenol-induced reduction of triglyceride synthesis was also detected. To clarify the lipid-lowering mechanism of these compounds, their influence on the activity of key enzymes of fatty acid biosynthesis (acetyl-CoA carboxylase and fatty acid synthase), triglyceride synthesis (diacylglycerol acyltransferase) and cholesterogenesis (3-hydroxy-3-methyl-glutaryl-CoA reductase) was investigated in situ by using digitonin-permeabilized hepatocytes. Acetyl-CoA carboxylase, diacylglycerol acyltransferase and 3-hydroxy-3-methyl-glutaryl-CoA reductase activities were reduced after 2 h of 25 μM phenol treatment. No change in fatty acid synthase activity was observed. Acetyl-CoA carboxylase inhibition (hydroxytyrosol, -41%, = oleuropein, -38%, > tyrosol, -17%) appears to be mediated by phosphorylation of AMP-activated protein kinase. These findings suggest that a decrease in hepatic lipid synthesis may represent a potential mechanism underlying the reported hypolipidemic effect of phenols of extra virgin olive oil.

Topics: Acetyl-CoA Carboxylase; AMP-Activated Protein Kinases; Animals; Cells, Cultured; Cholesterol; Diacylglycerol O-Acyltransferase; Down-Regulation; Fatty Acids; Hepatocytes; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Iridoid Glucosides; Iridoids; Lipids; Lipogenesis; Male; Olive Oil; Phenylethyl Alcohol; Phosphorylation; Plant Oils; Rats, Wistar

In the present study, the individual colonic metabolism of the main components of the virgin olive oil phenolic fraction was evaluated by an in vitro model using human faecal microbiota. To assess differences in metabolism related to the molecular structure, four phenolic standards were selected, tyrosol, hydroxytyrosol, hydroxytyrosol acetate and oleuropein. After studying the in vitro colonic metabolism pathways of the individual phenols, the presence of their colonic metabolites was investigated in human faecal samples obtained before and after the sustained intake (3 weeks) of a daily dose of 25 mL of a phenol-enriched olive oil.. The in vitro colon fermentation of the four individual phenolic compounds revealed (i) an increase in phenolic acids, (ii) the stability of hydroxytyrosol and tyrosol and (iii) the high degradation of hydroxytyrosol acetate and oleuropein. Additionally, a moderate intake of a phenol-rich olive oil raised the concentration in human faeces of free hydroxytyrosol and phenylacetic and phenylpropionic acids.. The products of colonic catabolism of olive oil phenolic compounds could be good candidates for novel preventive strategies and open a promising line of research into the preventive action of olive oil phenols in colon and other bowel diseases.

Topics: Acetates; Catechols; Colon; Feces; Fermentation; Humans; In Vitro Techniques; Iridoid Glucosides; Iridoids; Kinetics; Microbiota; Nontherapeutic Human Experimentation; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils

Refined edible oils (viz., oils from maize, soya, high-oleic sunflower, sunflower, olive, and rapeseed) enriched at two concentration levels (200 and 400 μg/mL total phenolic content) with phenolic extracts isolated from olive pomace and leaves have been characterized and compared with nonenriched oils and extra virgin olive oil (EVOO). Enriched oils were analyzed by LC-TOF/MS to generate representative fingerprints and compared with nonenriched oils and EVOO by unsupervised principal component analysis (PCA). The two raw materials reported enriched oils with profiles which were compared with those provided by EVOOs. Correlation analysis enabled us to establish the enriched oils with a composition more similar to EVOO. Discrimination according to the enrichment level depended on the raw material for extracts, and a global discussion about the enrichment on relevant phenolic compounds present in EVOO has reported quantitative results concerning the enrichment level for those significant compounds with known nutraceutical properties.

Topics: Antioxidants; Flavonoids; Furans; Iridoids; Lignans; Mass Spectrometry; Olea; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Extracts; Plant Leaves; Plant Oils; Principal Component Analysis

Olive (Olea europaea L.) fruits contain numerous secondary metabolites, primarily phenolics, terpenes and sterols, some of which are particularly interesting for their nutraceutical properties. This study will attempt to provide further insight into the profile of olive phenolic compounds during fruit development and to identify the major genetic determinants of phenolic metabolism.. The concentration of the major phenolic compounds, such as oleuropein, demethyloleuropein, 3-4 DHPEA-EDA, ligstroside, tyrosol, hydroxytyrosol, verbascoside and lignans, were measured in the developing fruits of 12 olive cultivars. The content of these compounds varied significantly among the cultivars and decreased during fruit development and maturation, with some compounds showing specificity for certain cultivars. Thirty-five olive transcripts homologous to genes involved in the pathways of the main secondary metabolites were identified from the massive sequencing data of the olive fruit transcriptome or from cDNA-AFLP analysis. Their mRNA levels were determined using RT-qPCR analysis on fruits of high- and low-phenolic varieties (Coratina and Dolce d'Andria, respectively) during three different fruit developmental stages. A strong correlation was observed between phenolic compound concentrations and transcripts putatively involved in their biosynthesis, suggesting a transcriptional regulation of the corresponding pathways. OeDXS, OeGES, OeGE10H and OeADH, encoding putative 1-deoxy-D-xylulose-5-P synthase, geraniol synthase, geraniol 10-hydroxylase and arogenate dehydrogenase, respectively, were almost exclusively present at 45 days after flowering (DAF), suggesting that these compounds might play a key role in regulating secoiridoid accumulation during fruit development.. Metabolic and transcriptional profiling led to the identification of some major players putatively involved in biosynthesis of secondary compounds in the olive tree. Our data represent the first step towards the functional characterisation of important genes for the determination of olive fruit quality.

Topics: Amplified Fragment Length Polymorphism Analysis; Biosynthetic Pathways; Cytochrome P-450 Enzyme System; Fruit; Gene Expression Profiling; Genes, Plant; Glucosides; Iridoid Glucosides; Iridoids; Metabolomics; Olea; Phenols; Phenylethyl Alcohol; Plant Oils; Plant Proteins; Prephenate Dehydrogenase; Pyrans; Real-Time Polymerase Chain Reaction; RNA, Messenger; Species Specificity; Transcriptome

Aculus olearius Castagnoli is a recently recorded species that damages olive fruits in the Mediterranean basin of Turkey. Thus, the effects of Eriophyid mites (Aculus olearius Castagnoli and Aceria oleae (Nalepa) (Acarina: Eriophyidae) on the olive fruits from Ayvalık variety in southern Turkey were studied for the first time in terms of some physical parameters and chemical constituents including some individual phenolics.. The Eriophyid damaged fruits had higher L* values (lighter colour) and tyrosol level (37.53 mg kg(-1) ) than the undamaged fruits (28.51 mg kg(-1) ) in August. In contrast, Eriophyid damaged fruits were darker in colour and had lower levels (25.77 mg kg(-1) ) of tyrosol than those of undamaged fruits (79.14 mg kg(-1) ) in October. Eriophyid damaged samples had higher values of vanillic acid than the undamaged samples. An increase in the average concentrations of hydroxytyrosol and p-coumaric acid was observed in the fruits harvested in August, whilst the oleuropein content decreased.. The harvest in October can be recommended regarding the higher dimensional values, total oil, dry matter and oleuropein contents. But the interaction between harvest time and Eriophyid damage was found effective in terms of tyrosol content and skin colour; as tyrosol values were lower in the fruits harvested in October and the fruits were darker. The resistance of undamaged fruits against Eriophyid damage can be linked to high tyrosol content of these fruits.

Topics: Animals; Color; Coumaric Acids; Fruit; Iridoid Glucosides; Iridoids; Mites; Olea; Phenylethyl Alcohol; Plant Diseases; Pyrans; Seasons; Species Specificity; Vanillic Acid

In 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) 18.6 μg/mL) and liquid ethanol at 150 °C (EC(50) 27.4 μg/mL), attaining at these conditions high extraction yields, around 40 and 30%, respectively. The particular phenolic composition of the obtained extracts was characterized by LC-ESI-MS. Using this method, 25 different phenolic compounds could be tentatively identified, including phenolic acids, secoiridoids, hydroxycinnamic acid derivatives, flavonols and flavones. Among them, hydroxytyrosol, oleuropein and luteolin-glucoside were the main phenolic antioxidants and were quantified on the extracts together with other minor constituents, by means of a UPLC-MS/MS method. Results showed that using water as extracting agent, the amount of phenolic compounds increased with the extraction temperature, being hydroxytyrosol the main phenolic component on the water PLE olive leaves extracts, reaching up to 8.542 mg/g dried extract. On the other hand, oleuropein was the main component on the extracts obtained with ethanol (6.156-2.819 mg/g extract). Results described in this work demonstrate the good possibilities of using PLE as a useful technique for the valorization of by-products from the olive oil industry, such as olive leaves.

Topics: Analysis of Variance; Antioxidants; Chromatography, High Pressure Liquid; Coumaric Acids; Ethanol; Flavonoids; Hot Temperature; Iridoids; Liquid-Liquid Extraction; Olea; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Leaves; Plant Oils; Pressure; Tandem Mass Spectrometry; Water

The purpose of the present study was to evaluate the in vitro antibacterial effects of different classes of important and common dietary phytochemicals (5 simple phenolics - tyrosol, gallic acid, caffeic acid, ferulic acid, and chlorogenic acid; chalcone - phloridzin; flavan-3-ol - (-) epicatechin; seco-iridoid - oleuropein glucoside; 3 glucosinolate hydrolysis products - allylisothiocyanate, benzylisothiocyanate and 2-phenylethylisothiocyanate) against Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes and Staphylococcus aureus. Another objective of this study was to evaluate the effects of dual combinations of streptomycin with the different phytochemicals on antibacterial activity. A disc diffusion assay was used to evaluate the antibacterial activity of the phytochemicals and 3 standard antibiotics (ciprofloxacin, gentamicin and streptomycin) against the four bacteria. The antimicrobial activity of single compounds and dual combinations (streptomycin-phytochemicals) were quantitatively assessed by measuring the inhibitory halos. The results showed that all of the isothiocyanates had significant antimicrobial activities, while the phenolics were much less efficient. No antimicrobial activity was observed with phloridzin. In general P. aeruginosa was the most sensitive microorganism and L. monocytogenes the most resistant. The application of dual combinations demonstrated synergy between streptomycin and gallic acid, ferulic acid, chlorogenic acid, allylisothiocyanate and 2-phenylethylisothiocyanate against the Gram-negative bacteria. In conclusion, phytochemical products and more specifically the isothiocyanates were effective inhibitors of the in vitro growth of the Gram-negative and Gram-positive pathogenic bacteria. Moreover, they can act synergistically with less efficient antibiotics to control bacterial growth.

Topics: Anti-Bacterial Agents; Catechin; Cinnamates; Drug Combinations; Drug Evaluation, Preclinical; Drug Synergism; Escherichia coli; Gallic Acid; Hydrolysis; Iridoid Glucosides; Iridoids; Isothiocyanates; Listeria monocytogenes; Phenylethyl Alcohol; Phlorhizin; Pseudomonas aeruginosa; Pyrans; Staphylococcus aureus; Streptomycin

Oleuropein (Ole), hydroxytyrosol (Htyr), and tyrosol (Tyr) are three of the main phenolic compounds present in the olive tree (Olea europaea L.) that have important antioxidant properties. To investigate the role of these phenolic compounds in the metabolism of stems and roots of Olea europaea L. cv. Picual during olive ripening, we identify and quantify the concentration of Htyr, Tyr, and Ole by reversed-phase high-performance liquid chromatography (RP-HPLC). Rain-fed olive trees, 30 years old, under traditional cultivation were studied in Jaén (Spain). From August to November, seven representative samples of the ripening process were taken.. The concentration of these phenolic compounds proved higher in the stems than in the roots. From the middle of September to October the Htyr and Tyr concentration significantly increased in stems. The Ole concentration increased from the middle of September to the end of November. In the roots, the concentration of Htyr and Ole significantly declined during ripening.. Ole, Htyr, and Tyr are present in the stems and roots of the olive tree and significantly change in concentration during ripening, demonstrating the involvement of these compounds in the metabolism of both organs during this phase.

Topics: Antioxidants; Chromatography, High Pressure Liquid; Fruit; Iridoid Glucosides; Iridoids; Olea; Phenylethyl Alcohol; Plant Leaves; Plant Roots; Plant Stems; Pyrans; Seasons; Spain; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

A comparison between the results obtained by using HPLC-UV, HPLC-MS, and CE-UV for characterizing the deterioration of extra-virgin olive oil during heating (180 degrees C) was investigated, taking into account phenolic compounds. The concentration of several compounds belonging to four families of phenols (simple phenols, lignans, complex phenols, and phenolic acids) was determined in the samples after the thermal treatment by all three techniques. Hydroxytyrosol, elenolic acid, decarboxymethyl oleuropein aglycon, and oleuropein aglycon reduced their concentration with the thermal treatment more quickly than other phenolic compounds present in olive oil. HYTY-Ac and Lig Agl were demonstrated to be quite resistant to this kind of treatment, and the behavior of lignans could be outstanding, as they belong to the family most resistant to thermal treatment. Several "unknown" compounds were determined in the phenolic profiles of the oils after the thermal treatment, and their presence was confirmed in refined olive oils. The oxidative stability index (OSI time) was reduced from 25 to 5 h after 3 h of heating, whereas the peroxide value showed a minimum after 1 h of heating.

Topics: 3,4-Dihydroxyphenylacetic Acid; Antioxidants; Chromatography, High Pressure Liquid; Drug Stability; Electrophoresis, Capillary; Glucosides; Iridoid Glucosides; Iridoids; Mass Spectrometry; Olive Oil; Oxidation-Reduction; Peroxides; Phenols; Phenylethyl Alcohol; Plant Oils; Pyrans; Spectrophotometry, Ultraviolet; Thermodynamics

The aim of the current study was to investigate the antioxidant and cellular activity of the olive oil phenolics oleuropein, tyrosol, hydroxytyrosol, and homovanillic alcohol (which is also a major metabolite of hydroxytyrosol). Well-characterized chemical and biochemical assays were used to assess the antioxidant potential of the compounds. Further experiments investigated their influence in cell culture on cytotoxic effects of hydrogen peroxide and oxidized low-density lipoprotein (LDL), nitric oxide production by activated macrophages, and secretion of chemoattractant and cell adhesion molecules by the endothelium. Inhibitory influences on in vitro platelet aggregation were also measured. The antioxidant assays indicated that homovanillic alcohol was a significantly more potent antioxidant than the other phenolics, both in chemical assays and in prolonging the lag phase of LDL oxidation. Cell culture experiments suggested that the olive oil phenolics induce a significant reduction in the secretion of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 (and a trend towards a reduced secretion of monocyte chemoattractant protein-1), and protect against cytotoxic effects of hydrogen peroxide and oxidized LDL. However, no influence on nitric oxide production or platelet aggregation was evident. The data show that olive oil phenolics have biochemical and cellular actions, which, if also apparent in vivo, could exert cardioprotective effects.

Topics: Antioxidants; Arteriosclerosis; Cell Adhesion Molecules; Cells, Cultured; Chemokine CCL2; Endothelium; Homovanillic Acid; Hydrogen Peroxide; In Vitro Techniques; Intercellular Adhesion Molecule-1; Iridoid Glucosides; Iridoids; Lipoproteins, LDL; Macrophages; Nitric Oxide; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Platelet Aggregation; Pyrans; Vascular Cell Adhesion Molecule-1

In search for compounds, able to protect nuclear DNA in cells exposed to oxidative stress, extracts from olive leaves, olive fruits, olive oil and olive mill waste water were tested by using the "single cell gel electrophoresis" methodology (comet assay). Jurkat cells in culture were exposed to continuously generated hydrogen peroxide (11.8+/-1.5 microM per min) by direct addition into the growth medium of the appropriate amount of the enzyme "glucose oxidase" in the presence or absence of the tested total extracts. The protective effects of the tested extracts or isolated compounds were evaluated from their ability to decrease hydrogen peroxide-induced formation of single strand breaks in the nuclear DNA, while the toxic effects were estimated from the increase of DNA damage when the extracts or isolated compounds were incubated directly with the cells. Significant protection was observed in extracts from olive oil and olive mill waste water. However, above a concentration of 100 microg/ml olive oil extracts exerted DNA damaging effects by themselves in the absence of any H2O2. Extracts from olive leaves and olive fruits although protective, were also able to induce DNA damage by themselves. Main compounds isolated from the above described total extracts, like oleuropein glucoside, tyrosol, hydroxytyrosol and caffeic acid, were tested in the same experimental system and found to exert cytotoxic (oleuropein glucoside), no effect (tyrosol) or protective effects (hydroxytyrosol and caffeic acid). In conclusion, cytoprotective as well as cytotoxic compounds with potential pharmaceutical properties were detected in extracts from olive oil related sources by using the comet assay methodology.

Topics: Caffeic Acids; Chromatography, High Pressure Liquid; Comet Assay; DNA; DNA Damage; Humans; Hydrogen Peroxide; Iridoid Glucosides; Iridoids; Jurkat Cells; Nuclear Magnetic Resonance, Biomolecular; Olea; Olive Oil; Phenylethyl Alcohol; Plant Extracts; Plant Oils; Pyrans

A capillary zone electrophoresis method has been carried out to determine and quantitate some compounds of the polyphenolic fraction of virgin olive oil which have never previously been determined before using capillary electrophoresis, such as elenolic acid, ligstroside aglycon, oleuropein aglycon, and (+)-pinoresinol. The compounds were identified using standards obtained by semipreparative high-performance liquid chromatography (HPLC). A detailed method optimization was performed to separate the phenolic compounds present in olive oil using a methanol-water extract of Picual extra-virgin olive oil, and different extraction systems were compared (C18-solid phase extraction (SPE), Diol-SPE, Sax-SPE and liquid-liquid extraction). The optimized parameters were 30 mM sodium tetraborate buffer (pH 9.3) at 25 kV with 8 s hydrodynamic injection, and the quantitation was carried out by the use of two reference compounds at two different wavelengths.

Topics: Chromatography, High Pressure Liquid; Electrophoresis, Capillary; Flavonoids; Furans; Glucosides; Iridoid Glucosides; Iridoids; Lignans; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Polyphenols; Pyrans

The structural modifications of the unsaturated fatty acid components of triglycerides in extra virgin olive oil (EVOO) following exposure to nitrite ions in acidic media were determined by two-dimensional (2D) NMR spectroscopy, aided by (15)N labeling and GC analysis, allowing investigation of the matrix without fractionation steps. In the presence of excess nitrite ions in a 1% sulfuric acid/oil biphasic system, extensive double bond isomerization of the oleic/linoleic acid components of triglycerides was observed associated with nitration/oxidation processes. Structurally modified species were identified as E/Z-nitroalkene, 1,2-nitrohydroxy, and 3-nitro-1-alkene(1,5-diene) derivatives based on (1)H, (13)C, and (15)N 2D NMR analysis in comparison with model compounds. Minor constituents of EVOO, including phenolic compounds and tocopherols, were also substantially modified by nitrite-derived nitrating species, even under milder reaction conditions relevant to those occurring in the gastric compartments. Novel nitrated derivatives of tyrosol, hydroxytyrosol, and oleuropein (6-8) were identified by LC/MS analysis of the polar fraction of EVOO and by comparison with synthetic samples. Overall, these results provide the first systematic description at the chemical level of the consequences of exposing EVOO to nitrite ions at acidic pH and offer an improved basis for further investigations in the field of toxic nitrosation/nitration reactions and dietary antinitrosating agents.

Topics: Acids; Alkenes; Antineoplastic Agents; Fatty Acids, Unsaturated; Gas Chromatography-Mass Spectrometry; Hydrogen-Ion Concentration; Ions; Iridoid Glucosides; Iridoids; Isomerism; Magnetic Resonance Spectroscopy; Nitrites; Nitrosation; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Pyrans

Epidemiology suggests that Mediterranean diets are associated with reduced risk of cardiovascular disease. Because monocyte adhesion to the endothelium is crucial in early atherogenesis, we evaluated whether typical olive oil and red wine polyphenols affect endothelial-leukocyte adhesion molecule expression and monocyte adhesion.. Phytochemicals in olive oil and red wine, including oleuropein, hydroxytyrosol, tyrosol, elenolic acid, and resveratrol, with or without antioxidant activity, were incubated with human umbilical vein endothelial cells for 30 minutes, followed by co-incubation with bacterial lipopolysaccharide or cytokines to trigger adhesion molecule expression. At nutritionally relevant concentrations, only oleuropein, hydroxytyrosol, and resveratrol, possessing a marked antioxidant activity, reduced monocytoid cell adhesion to stimulated endothelium, as well as vascular cell adhesion molecule-1 (VCAM-1) mRNA and protein by Northern analysis and cell surface enzyme immunoassay. Reporter gene assays with deletional VCAM-1 promoter constructs indicated the relevance of nuclear factor-kappaB, activator protein-1, and possibly GATA binding sites in mediating VCAM-1 transcriptional inhibition. The involvement of nuclear factor-kappaB and activator protein-1 was finally demonstrated at electrophoretic mobility shift assays.. Olive oil and red wine antioxidant polyphenols at nutritionally relevant concentrations transcriptionally inhibit endothelial adhesion molecule expression, thus partially explaining atheroprotection from Mediterranean diets.

Topics: Animals; Antioxidants; Arteriosclerosis; Cattle; Cell Adhesion; Cells, Cultured; Diet; Endothelium, Vascular; Flavonoids; Gene Expression Regulation; Humans; Iridoid Glucosides; Iridoids; NF-kappa B; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Polyphenols; Pyrans; Resveratrol; RNA, Messenger; Stilbenes; Transcription Factor AP-1; Transcription, Genetic; U937 Cells; Vascular Cell Adhesion Molecule-1; Wine

This study presents the phenolic compounds profile of commercial Cornicabra virgin olive oils from five successive crop seasons (1995/1996 to 1999/2000; n = 97), determined by solid phase extraction reversed phase high-performance liquid chromatography (SPE RP-HPLC), and its relationship with oxidative stability, processing conditions, and a preliminary study on variety classification. The median of total phenols content was 38 ppm (as syringic acid), although a wide range was observed, from 11 to 76 ppm. The main phenols found were the dialdehydic form of elenolic acid linked to tyrosol (p-HPEA-EDA; 9 +/- 7 ppm, as median and interquartile range), oleuropein aglycon (8 +/- 6 ppm), and the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA; 5 +/- 8 ppm). In many cases the correlation with oxidative stability was higher when the sum of the dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA) and oleuropein aglycon (r (2) = 0.91-0.96) or the sum of these two and hydroxytyrosol (r (2) = 0.90-0.97) was considered than was observed with HPLC total phenols (r (2)= 0.91-0.95) and especially with colorimetric determination of total polyphenols and o-diphenols (r (2) = 0.77-0.95 and 0.78-0.92, respectively). 3,4-DHPEA-EDA, p-HPEA-EDA, the aglycons of oleuropein and ligstroside, and HPLC total phenols content presented highly significant differences (p = 0.001-0.010) with respect to the dual- and triple-phase extraction systems used, whereas colorimetric total polyphenols content did not (p = 0.348) and o-diphenols showed a much lower significant difference (p = 0.031). The five variables that most satisfactorily classified the principal commercial Spanish virgin olive oil varieties were 1-acetoxypinoresinol, 4-(acetoxyethyl)-1,2-dihydroxybenzene (3,4-DHPEA-AC), ligstroside aglycon, p-HPEA-EDA, and RT 43.3 contents.

Topics: Chromatography, High Pressure Liquid; Colorimetry; Drug Stability; Flavonoids; Iridoid Glucosides; Iridoids; Olive Oil; Oxidation-Reduction; Phenols; Phenylethyl Alcohol; Plant Oils; Polymers; Polyphenols; Pyrans; Seasons

Animal and in vitro studies suggest that olive oil phenols are effective antioxidants. The most abundant phenols in olive oil are the nonpolar oleuropein- and ligstroside-aglycones and the polar hydroxytyrosol and tyrosol. The aim of this study was to gain more insight into the metabolism of those phenols in humans. We measured their absorption in eight healthy ileostomy subjects. We also measured urinary excretion in the ileostomy subjects and in 12 volunteers with a colon. Subjects consumed three different supplements containing 100 mg of olive oil phenols on separate days in random order. Ileostomy subjects consumed a supplement with mainly nonpolar phenols, one with mainly polar phenols and one with the parent compound oleuropein-glycoside. Subjects with a colon consumed a supplement without phenols (placebo) instead of the supplement with oleuropein-glycoside. Ileostomy effluent and urine were collected for 24 h after supplement intake. Tyrosol and hydroxytyrosol concentrations were low (< 4 mol/100 mol of intake) in the ileostomy effluent, and no aglycones were detected. We estimated that the apparent absorption of phenols was at least 55-66% of the ingested dose. Absorption was confirmed by the excretion of tyrosol and hydroxytyrosol in urine. In ileostomy subjects, 12 mol/100 mol and in subjects with a colon, 6 mol/100 mol of the phenols from the nonpolar supplement were recovered in urine as tyrosol or hydroxytyrosol. In both subject groups, 5--6 mol/100 mol of the phenols was recovered from the polar supplement. When ileostomy subjects were given oleuropein-glycoside, 16 mol/100 mol was recovered in 24-h urine, mainly in the form of hydroxytyrosol. Thus, humans absorb a large part of ingested olive oil phenols and absorbed olive oil phenols are extensively modified in the body.

Topics: Absorption; Adult; Colon; Dietary Supplements; Drug Stability; Female; Humans; Ileostomy; Iridoid Glucosides; Iridoids; Male; Olive Oil; Phenols; Phenylethyl Alcohol; Placebos; Plant Oils; Pyrans

The effects of the polyphenolic compounds from virgin olive oil: tyrosol, hydroxytyrosol and oleuropein on the non-enzymatic lipid peroxidation induced by ascorbate-Fe2+ of rat liver microsomes were examined. The inhibition of light emission (maximal induced chemiluminescence) by oleuropein was concentration dependent. Hydroxytyrosol showed a substantial degree of inhibition against ascorbate-Fe2+ induced lipid peroxidation in rat liver microsomes that was at least 6 times higher than that observed in the presence of oleuropein. Inhibition of lipid peroxidation by tyrosol was not observed. In rat liver microsomes incubated alone or in the presence of tyrosol, the fatty acid composition was profoundly modified when subjected to in vitro peroxidation mediated by ascorbate-Fe2+, with a considerable decrease of 18:2n6 and 20:4n6; however, changes in fatty acid composition were not observed when microsomes were incubated with hydroxytyrosol. When oleuropein was used at low concentration (5, 15 microM) a considerable decrease of 20:4n6 was observed, but 18:2n6 was not modified; at higher concentration (30, 60 microM) changes in fatty acid composition were not observed. There was a very good correlation between the presence of oxidized phospholipids and the changes in polyunsaturated fatty acids previously observed. Thus, hydroxytyrosol showed the highest protection again oxidized phospholipid formation. The presence of oleuropein at low concentration (5, 15 microM) does not prevent the formation of oxidized phospholipids (8.02 +/- 1.22 and 1.22 +/- 1.22) but concentration higher than 30 microM avoids completely the formation of this molecules whereas tyrosol at any concentration assayed was found to be ineffective and allows the formation not only of oxidized phospholipids but also of oxidized cholesterol.

Topics: Animals; Cholesterol; Fatty Acids; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Microsomes, Liver; Oxidation-Reduction; Phenylethyl Alcohol; Phospholipids; Pyrans; Rats; Rats, Wistar

The phenolic composition of olive fruits (Olea europaea L.) (cv. Picual, Villalonga, Alfafarenca, and Cornicabra) grown in different areas of Spain was studied by high performance liquid chromatography-mass spectrometry. Different levels of tyrosol, catechin, p-coumaric acid, rutin, luteolin, and oleuropein were observed in the different varieties analyzed. Treating the fruit with 0.3% Brotomax 50 days after anthesis had a beneficial effect on fruit size, oil content, levels of polyphenolic compounds, and Trolox-equivalent antioxidant activity (TEAC) in all the varieties analyzed.

Topics: Antioxidants; Catechin; Chromatography, High Pressure Liquid; Coumaric Acids; Flavonoids; Fruit; Iridoid Glucosides; Iridoids; Luteolin; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Propionates; Pyrans; Rutin

The major phenolics from the polar fraction of virgin olive oil (caffeic acid, oleuropein, tyrosol and hydroxytyrosol) have well-established antioxidant activities but their effects on reactive nitrogen species and nitrergic neurotransmission have not been fully investigated. The three catechol compounds were active as scavengers of nitric oxide generated spontaneously from the decomposition of sodium nitroprusside (approximately 50% inhibition achieved at 75 microM), and had similar ability to scavenge chemically generated peroxynitrite, as determined by an alpha1-antiproteinase inactivation assay (67.2%-92.4% reduction when added at 1 mM). Tyrosol was less active in these tests, but does not possess the catechol functionality. Despite their ability to interact with chemically prepared nitric oxide, neither oleuropein nor hydroxytyrosol at 5 microM altered NO*-mediated relaxations of the nerve-stimulated rat anococcygeus preparation, but this may be because the nitrergic transmitter is protected from the effects of externally applied scavengers. In conclusion, the phenolics found in virgin olive oil possess ability to scavenge reactive oxygen and nitrogen species that are implicated in human pathologies, but their impact may be restricted to those species present in the extracellular environment.

Topics: Animals; Antioxidants; Caffeic Acids; Dose-Response Relationship, Drug; Free Radical Scavengers; Iridoid Glucosides; Iridoids; Male; Muscle Relaxation; Muscle, Smooth; Neural Conduction; Nitrates; Nitric Oxide; Nitroprusside; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Pyrans; Rats; Rats, Wistar

Interest in the health-promoting effects of virgin olive oil, an important part of the 'Mediterranean diet', prompted us to determine the anti-eicosanoid and antioxidant effects in leukocytes of the principal phenolic compounds from the 'polar fraction': oleuropein, tyrosol, hydroxytyrosol, and caffeic acid. In intact rat peritoneal leukocytes stimulated with calcium ionophore, all four phenolics inhibited leukotriene B4 generation at the 5-lipoxygenase level with effectiveness hydroxytyrosol > oleuropein > caffeic acid > tyrosol (approximate EC50 values: 15, 80, 200, and 500 microM, respectively). In contrast, none of these compounds caused substantial inhibition of thromboxane generation via the cyclo-oxygenase pathway. Hydroxytyrosol, caffeic acid, oleuropein, and tyrosol (decreasing order of effectiveness) also quenched the chemiluminescence signal due to reactive oxygen species generated by phorbol myristate acetate-stimulated rat leukocytes. None of these compounds were toxic to leukocytes at the concentrations tested. We conclude that the phenolics found in virgin olive oil possess an array of potentially beneficial lipoxygenase-inhibitory, prostaglandin-sparing, and antioxidant properties.

Topics: Animals; Antioxidants; Caffeic Acids; Dietary Fats, Unsaturated; Eicosanoids; Iridoid Glucosides; Iridoids; Leukocytes; Lipoxygenase Inhibitors; Male; Olive Oil; Phenylethyl Alcohol; Plant Oils; Pyrans; Rats; Rats, Wistar; Reactive Oxygen Species

Substantial evidence suggests that oxidative modifications of low density lipoproteins (LDL) critically contribute to the pathogenesis and progression of human atherosclerosis. Oxidized LDL (oxLDL) are present in atherosclerotic plaques and contain oxysterols that exhibit a variety of adverse biological activities. Antioxidants have also been shown to prevent LDL modification. We have therefore assessed the efficacy of virgin olive oil phenolic compounds in preventing oxidative modifications of human LDL oxidized by UV light.. Cholesterol oxides formed during LDL photo-oxidation were determined by UV-HPLC in the presence of different concentrations of phenolic compounds and their pure components (tyrosol and oleuropein), and probucol, a widely used synthetic antioxidant. Electrophoretic mobility was also assayed. The results demonstrate that phenolic compounds are much more potent in preventing cholesterol oxide formation and apoproteic moiety modification than their pure components and probucol.. The beneficial effects of a Mediterranean diet may be ascribable not only to the high unsaturated/saturated fatty acid ratio characteristic of olive oil, but also to the unique antioxidant properties of its phenolic compounds.

Topics: Anticholesteremic Agents; Antioxidants; Cholesterol; Chromatography, High Pressure Liquid; Electrophoresis, Agar Gel; Humans; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Lipoproteins, LDL; Olive Oil; Phenols; Phenylethyl Alcohol; Plant Oils; Probucol; Pyrans; Ultraviolet Rays

Oleuropein, tyrosol, squalene and the fraction of sterols and triterpenoid dialcohols from the unsaponifiable fraction obtained from virgin olive oil have been tested for possible cytostatic activity against McCoy cells, using 6-mercaptopurine as a positive control. The samples of sterols and triterpenic dialcohols showed a strong activity.

Topics: Antineoplastic Agents, Phytogenic; Cell Division; Cell Line; Humans; Iridoid Glucosides; Iridoids; Olive Oil; Phenylethyl Alcohol; Plant Oils; Pyrans; Squalene; Sterols; Triterpenes