2-4-3--5--tetrahydroxystilbene and ligstroside

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

Phenolic compounds largely contribute to the nutraceutical properties of virgin olive oil (VOO), the organoleptic attributes and the shelf life due to their antioxidant capabilities. Due to the relevance of malaxation in the oil extraction process, we tested the effects of malaxation time on the concentrations of relevant phenolic compounds in VOO, and we evaluated the influence of performing malaxation under vacuum. An increase in malaxation time significantly decreased the concentrations of aglycone isomers of oleuropein and ligstroside but, conversely, increased the oleocanthal and oleacein contents. Additionally, malaxation under vacuum led to an increase in phenolic contents compared to standard conditions carried out at atmospheric pressure. Finally, we explored the possibility of predicting the VOO oxidative stability on the basis of the phenolic profile, and a model (R

Topics: Aldehydes; Cyclopentane Monoterpenes; Fatty Acids; Food Handling; Glucosides; Iridoid Glucosides; Iridoids; Olive Oil; Oxidation-Reduction; Phenols; Pyrans; Temperature; Time Factors

Topics: Aging; Aldehydes; Alzheimer Disease; Animals; Brain; Cell Line; Cell Respiration; Cyclopentane Monoterpenes; Disease Models, Animal; Female; Glucosides; Humans; Mice; Mitochondria; Neurons; Neuroprotective Agents; Phenols; Pyrans

'Brava' and 'Mansa de Figueiredo' extra-virgin olive oils (EVOOs) are two varieties identified from north-western Spain. A systematic phenolic characterization of the studied oils was undertaken by LC-ESI-IT-MS. In addition, the role of dietary polyphenols from these EVOOs has been evaluated against the inhibition of key enzymes (α-glucosidase and α-amylase) in the management of diabetes mellitus (DM). Oleuropein and ligstroside derivatives comprised 83% and 67% of the total phenolic compounds in 'Brava' and 'Mansa de Figueiredo' EVOOs, respectively. The main secoiridoids from oleuropein were DOA (3,4-DHPEA-EDA, 59 and 22 mg kg

Topics: Aldehydes; alpha-Amylases; alpha-Glucosidases; Cyclopentane Monoterpenes; Diabetes Mellitus, Type 2; Flavonoids; Glucosides; Glycoside Hydrolase Inhibitors; Hypoglycemic Agents; Iridoid Glucosides; Iridoids; Olive Oil; Phenols; Plant Extracts; Pyrans; Spain

Fatty acids, phenolic compounds, and tocopherols of Coratina, Bosana, Semidana, and Tonda di Cagliari virgin olive oils, were measured over a 45-day harvest period. Phenolic composition was the primary factor distinguishing Bosana, Tonda di Cagliari, and Semidana, whereas fatty acids differentiated Coratina and the other cultivars. Harvest period principally influenced oleacein, oleocanthal, oleuropein and ligstroside aglycones, and flavonoids. High phenolic content was observed for Coratina (1039-688 mg/kg) and Bosana (788-592 mg/kg). A drastic decrease in phenolic content was observed in Semidana (529-134 mg/kg) and Tonda di Cagliari (507-142 mg/kg) during the harvest period. These two cultivars also had low MUFA/PUFA (6.0-4.0 and 4.9-3.2 respectively), suggesting that these varieties should be harvested earlier in the season. These results provide information to producers for improved management of the harvesting process, which is strongly affected by varietal factors.

Topics: Agriculture; Aldehydes; Cyclopentane Monoterpenes; Fatty Acids; Flavonoids; Food Analysis; Glucosides; Iridoid Glucosides; Iridoids; Italy; Olea; Olive Oil; Phenols; Pyrans; Species Specificity; Tocopherols

Despite the evident influence of the cultivar on olive oil composition, few studies have been devoted to exploring the variability of phenols in a representative number of monovarietal olive oils. In this study, oil samples from 80 cultivars selected for their impact on worldwide oil production were analyzed to compare their phenolic composition by using a method based on LC-MS/MS. Secoiridoid derivatives were the most concentrated phenols in virgin olive oil, showing high variability that was significantly due to the cultivar. Multivariate analysis allowed discrimination between four groups of cultivars through their phenolic profiles: (i) richer in aglycon isomers of oleuropein and ligstroside; (ii) richer in oleocanthal and oleacein; (iii) richer in flavonoids; and (iv) oils with balanced but reduced phenolic concentrations. Additionally, correlation analysis showed no linkage among aglycon isomers and oleocanthal/oleacein, which can be explained by the enzymatic pathways involved in the metabolism of both oleuropein and ligstroside.

Topics: Aldehydes; Biological Variation, Population; Chromatography, Liquid; Cyclopentane Monoterpenes; Flavonoids; Glucosides; Iridoid Glucosides; Iridoids; Multivariate Analysis; Olea; Olive Oil; Phenols; Phytochemicals; Pyrans; Tandem Mass Spectrometry

The dialdehydes oleacein (2) and oleocanthal (4) are closely related to oleuropein (1) and ligstroside (3), the two latter compounds being abundant iridoids of Olea europaea. By exploiting oleuropein isolated from the plant leaf extract, an efficient procedure has been developed for a one-step semisynthesis of oleacein under Krapcho decarbomethoxylation conditions. Highlighted is the fact that 5-lipoxygenase is a direct target for oleacein with an inhibitory potential (IC50: 2 μM) more potent than oleocanthal (4) and oleuropein (1). This enzyme catalyzes the initial steps in the biosynthesis of pro-inflammatory leukotrienes. Taken together, the methodology presented here offers an alternative solution to isolation or total synthesis for the procurement of oleacein, thus facilitating the further development as a potential anti-inflammatory agent.

Topics: Aldehydes; Anti-Inflammatory Agents; Arachidonate 5-Lipoxygenase; Cyclopentane Monoterpenes; Glucosides; Humans; Iridoid Glucosides; Iridoids; Lipoxygenase Inhibitors; Molecular Structure; Olea; Phenols; Plant Extracts; Plant Leaves; Pyrans