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Olive oil is a key component of the highly cardiovascular protective Mediterranean diet. (−)-Oleocanthal (OLC) is one of the most interesting phenolics present in virgin olive oil, and is formed from secoiridoid ligustroside during the processing of olives to yield the oil. Anti-inflammatory and anti-oxidant properties were identified shortly after OLC isolation, followed by the discovery of anti-tumor activities in a few nonhematopoietic cell lineages. Because of the scarcity of tissues potentially targeted by OLC analyzed so far and the unresolved mechanism(s) for OLC anti-tumor properties, we used a panel of 17 cell lines belonging to 11 tissue lineages to carry out a detailed examination of targets and pathways leading to cell growth inhibition and death. We found that OLC inhibits cell proliferation and induces apoptotic death as revealed by sub-G1 cell cycle analyses and Annexin-V staining in all lineages analyzed except lung carcinoma cell lines. Hematopoietic tumor cell lines, untested until now, were the most sensitive to OLC treatment, whereas non-transformed cells were significantly resistant to cell death. The specificity of OLC-mediated caspase activation was confirmed by blocking experiments and the use of transfectants overexpressing anti apoptotic genes. OLC triggers typical mediators of the intrinsic apoptotic pathway such as production of reactive oxygen species and mitochondrial membrane depolarization (Δψm). Complete blockade of caspases, however, did not result in parallel abrogation of Annexin-V staining, thus suggesting that complex mechanisms are involved in triggering OLC-mediated cell death. Our results demonstrate that OLC preferentially targets hematopoietic tumor cell lines and support that cell death is mediated by caspase-dependent and independent mechanisms., Universidad de Granada-Junta de Andalucia A-CTS-480-UGR18 B.CTS.690.UGR20, Action for AT, United Kingdom charity AAT-8GRA02

Sweet cherry (Prunus avium L.) is a tree widely cultivated in temperate regions for its tasty and healing fruits. Pruning works on the tree give each year considerable amounts of woody wastes that hardly have any utility. The aims of this work were to detect the most active antioxidants present in a cherry pruning wood sample, to isolate and characterize them, and study the antimicrobial and antibiofilm activities of components found in the wood ethyl acetate extract against a selection of foodborne microorganisms. The online HPLC–DPPH technique allowed the detection of two active antioxidant peaks that, after being isolated by a combination of countercurrent chromatography (FCPC) and conventional preparative techniques, and subsequent structural characterization by NMR, MS and polarimetry, resulted to be (‒)-catechin (1) and (‒)-taxifolin (4). Other components of the cherry wood extract were also isolated, among which compounds 1, 4, and (+)-dihydrowogonin (12) have never been reported in P. avium. A selection of the isolated flavonoids was submitted to antimicrobial and antibiofilm activity evaluations against strains from type culture collections, as well as on multi-resistant strains previously isolated in our laboratory. Those compounds with antimicrobial activity detected in preliminary screenings by standard agar diffusion tests ‒the flavan-3-ol 1, the flavanonols 4 and (+)-aromadendrin (5), the flavanone (+)-pinocembrin (15), and the flavone tectochrysin (17)‒ were subjected to the minimal inhibitory concentration (MIC) test, showing all of them MIC values of 100 μg/mL. Compound 4 also induced a significative inhibition on the formation of biofilms by Enterobacter sp. UJA37p at a concentration of 1 μg/mL and a significative disruption of preformed biofilm by this strain at 0.1 µg/mL. Similar results on biofilm disruption were observed with compound 17.

Cinnamtannin B-1 (C-B1) is a commercially-available trimeric A-type procyanidin with remarkable cellular actions mainly derived from its high radical scavenging activity. C-B1 is the main phenolic compound of laurel wood, which has previously been isolated by a combination of conventional chromatographic techniques. The first aim of this work was to find laurel trees containing as much C-B1 as possible, and learn about the influence of variables, such as gender and harvest time, on the production of C-B1 by the tree. It was found that all studied trees tend to give higher C-B1 percentages in the May-July period, from 6 % to 18 %, and lower ones around March (spring) and November (fall), from 1 % to 8 %. In a general way, it also seems that the female trees tend to produce a bit more C-B1 (from 2.8 % to 17.3 %) than male ones (from 1.7 % to 13.4 %). In addition, eight minor phenolic compounds [(-)-ent-catechin (1), (-)-ent-epicatechin-(4α→8)-ent-epicatechin (2), (epi)catechin-(4→8)-(epi)afzelechin-(4→8)-(epi)catechin (3), (+)-epiafzelechin-(4β→8)-epicatechin (4), (-)-epicatechin (5), (-)-afzelechin-(4α→8)-epicatechin (6), (epi)afzelechin-(4→8)-(epi)afzelechin-(4→8)-(epi)catechin (7) and (+)-epicatechin-(4β→8,2β→O-7)-epicatechin-(4β→8)-catechin (C-D1)] were found and quantified in the ethyl acetate extract of the wood samples. The second aim of this work was to improve the recovery of C-B1 from laurel wood. The use of the fast centrifugal partition chromatography (FCPC) technique has allowed for a recovery of 96 % of a technical-grade C-B1 (64 % in a previous protocol using conventional column chromatography on silica gel and size-exclusion chromatography).

The antioxidant and anti-inflammatory responses of (−)-methyl-oleocanthal (met-OLE), a new metabolite of the extra virgin olive oil (EVOO) phenolic oleocanthal (OLE), were explored in lipopolysaccharide (LPS)-induced murine peritoneal macrophages. Possible signaling pathways and epigenetic modulation of histones were studied. Met-OLE inhibited LPS-induced intracellular reactive oxygen species (ROS) and nitrite (NO) production and decreased the overexpression of the pro-inflammatory enzymes COX-2, mPGES-1 and iNOS in murine macrophages. In addition, met-OLE was able to significantly decrease the activation of p38, JNK, and ERK mitogen-activated protein kinases (MAPKs) and blocked canonical and non-canonical inflammasome signaling pathways. On the contrary, met-OLE upregulated haem oxigenase 1 (HO-1) and nuclear factor (erythroid-derived 2)-like 2 (Nrf-2) expression in treated cells. Finally, met-OLE pretreated spleen cells counteracted LPS induction, preventing H3K18 acetylation or H3K9 and H3K27 demethylation. Overall, these results provide novel mechanistic insights into the beneficial effects of met-OLE regarding the regulation of the immune–inflammatory response through epigenetic changes in histone markers. This revealing evidence suggests that the methylated metabolite of OLE may contribute significantly to the beneficial effects that are associated with the secoiridoid-related compound and the usual consumption of EVOO. España Ministerio de Economía y Competitividad grant number AG-2017-89342-P Junta de Andalucía funded by CTS-259, FQM-182

Triple negative breast cancer is an aggressive type of cancer that does not respond to hormonal therapy and current therapeutic strategies are accompanied by side effects due to cytotoxic actions on normal tissues. Therefore, there is a need for the identification of anti-cancer compounds with negligible effects on non-tumoral cells. Here we show that (−)‑oleocanthal (OLCT), a phenolic compound isolated from olive oil, selectively impairs MDA-MB-231 cell proliferation and viability without affecting the ability of non-tumoral MCF10A cells to proliferate or their viability. Similarly, OLCT selectively impairs the ability of MDA-MB-231 cells to migrate while the ability of MCF10A to migrate was unaffected. The effect of OLCT was not exclusive for triple negative breast cancer cells as we found that OLCT also attenuate cell viability and proliferation of MCF7 cells. Our results indicate that OLCT is unable to induce Ca2+ mobilization in non-tumoral cells. By contrast, OLCT induces Ca2+ entry in MCF7 and MDA-MB-231 cells, which is impaired by TRPC6 expression silencing. We have found that MDA-MB-231 and MCF7 cells overexpress the channel TRPC6 as compared to non-tumoral MCF10A and treatment with OLCT for 24–72 h downregulates TRPC6 expression in MDA-MB-231 cells. These findings indicate that OLCT impairs the ability of breast cancer cells to proliferate and migrate via downregulation of TRPC6 channel expression while having no effect on the biology of non-tumoral breast cells.

Primary hyperoxalurias (PHs) are a group of inherited alterations of the hepatic glyoxylate metabolism. PHs classification based on gene mutations parallel a variety of enzymatic defects, and all involve the harmful accumulation of calcium oxalate crystals that produce systemic damage. These geographically widespread rare diseases have a deep impact in the life quality of the patients. Until recently, treatments were limited to palliative measures and kidney/liver transplants in the most severe forms. Efforts made to develop pharmacological treatments succeeded with the biotechnological agent lumasiran, a siRNA product against glycolate oxidase, which has become the first effective therapy to treat PH1. However, small molecule drugs have classically been preferred since they benefit from experience and have better pharmacological properties. The development of small molecule inhibitors designed against key enzymes of glyoxylate metabolism is on the focus of research. Enzyme inhibitors are successful and widely used in several diseases and their pharmacokinetic advantages are well known. In PHs, effective enzymatic targets have been determined and characterized for drug design and interesting inhibitory activities have been achieved both in vitro and in vivo. This review describes the most recent advances towards the development of small molecule enzyme inhibitors in the treatment of PHs, introducing the multi-target approach as a more effective and safe therapeutic option.

Background Gene flow and polyploidy have been found to be important in Juniperus evolution. However, little evidence has been published elucidating the association of both phenomena in juniper taxa in the wild. Two main areas were studied in Spain (Eastern Iberian Range and Sierra de Baza) with both diploid and tetraploid taxa present in sympatry. Gene flow and ploidy level were assessed for these taxa and the resulted offspring. Results Twenty-two allo-triploid hybrids between J. sabina var. sabina and J. thurifera were found in the Eastern Iberian Range population. However, in the Sierra de Baza population no triploids were found. Instead, 18 allo-tetraploid hybrids between two tetraploid taxa: J. sabina var. balkanensis and J. thurifera were discovered. High genetic diversity was exhibited among the tetraploid hybrids at Sierra de Baza, in contrast to the genetically identical triploid hybrids at the Eastern Iberian Range; this suggests meiotic difficulties within the triploid hybrids. In addition, unidirectional gene flow was observed in both studied areas. Conclusion Polyploidy and hybridization can be complementary partners in the evolution of Juniperus taxa in sympatric occurrences. Juniperus was shown to be an ideal coniferous model to study these two phenomena, independently or in concert.

A convenient method to synthesize A-type proanthocyanidin analogues from flavylium salts and π-nucleophiles has been developed. It was found that the thermodynamic stability of the starting flavylium salt, assessed by the measurement of the apparent acidity constant ( K'

Summary This study aimed to evaluate the antimicrobial and antibiofilm activities of two procyanidins isolated from an ethyl acetate extract of laurel wood against a selection of foodborne pathogens. The analysis of the extract by HPLC–DAD/ESI–MS allowed us to detect the presence of two procyanidins, which were selectively isolated and identified by chromatographic and spectroscopic means as cinnamtannin B-1 (1) and procyanidin B-2 (2). Procyanidins 1 and 2 exhibited two biological activities: inhibition of bacterial growth at high concentrations and prevention of biofilm formation at lower concentrations. Synergistic effect was also detected when both compounds were tested in combination against Listeria monocytogenes. Significant effects were also detected on disruption of preformed biofilm. The ability of procyanidins to inhibit microbial growth and biofilm formation and to synergistically work with each other may stimulate a market as natural food preservatives, and/or natural sanitisers for processing equipment where foodborne pathogens reside.

Laurel tree (Laurus nobilis L.) wood is a byproduct of the pruning of this tree widely cultivated for its aromatic leaves. The phenolic composition of laurel wood has not been reported yet. The aim of this work was to study the phenolic profile of an ethyl acetate extract of laurel wood in order to know its potential as a source of antioxidants and valuable compounds. Three flavan-3-ols, 4 dimeric B-type proanthocyanidins, and 2 trimeric A-type procyanidins were isolated by preparative column chromatography and semi-preparative HPLC, using a fast online post-column radical scavenging detection technique as guidance. All isolated compounds were fully characterized by spectroscopic (NMR, IR, UV) and spectrometric (MS) techniques. In addition, 17 minor proanthocyanidins were tentatively identified by liquid chromatography coupled to mass spectrometry (HPLC–ESI–MS). The extract was dominated by the presence of cinnamtannin B-1, a bioactive trimeric A-type procyanidin reported as a strong antioxidant of commercial value. According to the chemical composition found, it can be concluded that laurel wood is a renewable source of potential bioactive phenolic compounds.

Five new bulky moiety-modified analogues of the sandalwood odorant Polysantol have been synthesized by aldol condensation of appropriate aldehydes with butanone, deconjugative alpha-methylation of the resulting alpha,beta-unsaturated ketones, and reduction of the corresponding beta,gamma-unsaturated ketones. The final compounds were evaluated organoleptically and one of them seemed to be of special interest for its natural sandalwood scent.

The yield and composition of essential oils from leaves, stems, umbel rays and also from whole aerial parts of Bupleurum gibraltarium Lam. (Apiaceae) were determined during the pre-flowering, full flowering, late flowering, and fruiting vegetative periods. A fruit sample was also studied for comparative purposes. Leaves (0.8–1.8% yield) and stems (0.3–0.7%) reached their maximum oil content during the late flowering period, whereas umbel rays (2.2–3.7%) reached it in full flowering. Oil samples were analyzed by capillary GC and GC/MS components which were found in amounts greater than 2% were selected to carry out a seasonal study. In the leaf oils, sabinene (12.0–33.9%) and limonene (7.8–23.4%) were the main components, the sabinene level being minimum in full flowering and maximum in fruiting. In stem oils, sabinene (4.7–21.6%) and 2,3,4-trimethylbenzaldehyde (9.3–13.6%) were the main components, the sabinene level being minimum in pre-flowering and maximum in full flowering. In umbel ray oils, sabinene (20.7–43.1%) was the first component in all the phenological periods, followed by α-pinene (7.3–28.2%). Both monoterpenes increased their levels in late flowering and reached minimum amounts in fruiting. © 2006, Taylor & Francis Group, LLC. All rights reserved.

The composition of the essential oils of 16 individual plants of Artemisia herba-alba Asso ssp. valentina (Lam.) Marcl. (at the full bloom stage) growing wild in four different locations from southern Spain were investigated by capillary GC and GC–MS in combination with retention indices. Among the 60 identified constituents (accounting for 80.6–95.0% of the oils), 33 have been reported for the first time in Spanish A. herba-alba oil and 17 of them have not been previously described in A. herba-alba oil. From the analysis of the oil samples, it could be deduced that a noticeable chemical polymorphism typified this taxon. Four groups of essential oils exhibited a single compound with percentages near 30% or higher: davanone, 1,8-cineole, chrysanthenone and cis-chrysanthenol. Two further oil types showed p-cymene and cis-chrysanthenyl acetate as major components in moderate amounts (ca. 20%). All of these types of essential oils have not been previously found in A. herba-alba from Spain and the appearance of such considerable amount of p-cymene is described here for the first time in A. herba-alba. # 2003 Published by Elsevier Ltd.

Iridoids are a major group of biologically active molecules that are present in thousands of plant species, and one versatile iridoid, secologanin, is a precursor for the assembly of thousands of monoterpenoid indole alkaloids (MIAs) as well as a number of quinoline alkaloids. This study uses bioinformatics to screen large databases of annotated transcripts from various MIA-producing plant species to select candidate genes that may be involved in iridoid biosynthesis. Virus-induced gene silencing of the selected genes combined with metabolite analyses of silenced plants was then used to identify the 7-deoxyloganic acid 7-hydroxylase (CrDL7H) that is involved in the 3rd to last step in secologanin biosynthesis. Silencing of CrDL7H reduced secologanin levels by at least 70%, and increased the levels of 7-deoxyloganic acid to over 4 mg g(-1) fresh leaf weight compared to control plants in which this iridoid is not detected. Functional expression of this CrDL7H in yeast confirmed its biochemical activity, and substrate specificity studies showed its preference for 7-deoxyloganic acid over other closely related substrates. Together, these results suggest that hydroxylation precedes carboxy-O-methylation in the secologanin pathway in Catharanthus roseus.

An investigation to optimize the extraction yield and the radical scavenging activity from the agricultural by-product olive tree wood (Olea europaeaL., cultivar Picual) using six different extraction protocols was carried out. Four olive wood samples from different geographical origin, and harvesting time have been used for comparison purposes. Among the fifty olive wood extracts obtained in this study, the most active ones were those prepared with ethyl acetate, either through direct extraction or by successive liquid-liquid partitioning procedures, the main components being the secoiridoids oleuropein and ligustroside. An acid hydrolysis pretreatment of olive wood samples before extractions did not improve the results. In the course of this study, two compounds were isolated from the ethanolic extracts of olive wood collected during the olives’ harvesting season and identified as (7′′R)-7′′-ethoxyoleuropein (1) and (7′′S)-7′′-ethoxyoleuropein (2).

Polyphenols, such as rosmarinic acid, are widely distributed natural products with relevant antioxidant activity. Oxidative stress plays an important role in the pathogenesis of a number of disorders. Here, we report on the synthesis and biological effects of the polyphenolic esters hydroxytyrosyl gallate (1), hydroxytyrosyl protocatechuate (2) and hydroxytyrosyl caffeate (3), structurally related to rosmarinic acid. The three compounds showed a greater free radical scavenging activity than their precursors and also than rosmarinic acid. Esters 1 and 3 significantly reduced thrombin-evoked platelet aggregation, which is likely mediated to the attenuation of thrombin-stimulated Ca(2+) release and entry. The three compounds reduced the ability of platelets to accumulate Ca(2+) in the intracellular stores, probably by enhancing the Ca(2+) leakage rate and reduced store-operated Ca(2+) entry in these cells. These observations suggest that the structurally-simplified analogs to rosmarinic acid, compounds 1 and 3, might be the base of therapeutic strategies to prevent thrombotic complications associated to platelet hyperaggregability due to oxidative stress.

A solution of bromine (0.3 mL, 5.90 mmol) in CCl4 (2 mL) was slowly added over a stirred mixture of 3-methyl-butan-2-one (1) (505 mg, 5.90 mmol) and AcOH (0.33 mL) at room temperature.[...]

The oils from the umbel rays, stems, leaves, fruits and the whole aerial parts of Bupleurum gibraltarium Lam. have been examined by means of GC/MS and retention indices. The dominant constituents in the oil from the whole aerial parts were found to be α-pinene (5.9%), sabinene (9.2%), limonene (6.5%), 2,3,4-trimethylbenzaldehyde (17.2%), terpinen4-ol (5.1%), trans-chrysanthenyl acetate (4.7%), elemol (4.3%) and guaiol (5.3%). The major components of the umbel rays oil were α-pinene (17.6%), sabinene (33.8%), limonene (7.3%), and 2,3,4-trimethyl-benzaldehyde (8.4%). The stem oil was characterized by the presence of α-pinene (6.0%), sabinene (21.8%), limonene (7.2%), 2,3,4-trimethylbenzaldehyde (10.7%), guaiol isomer (5.1%), elemol(5.5%) and guaiol (5.4%). The leaf oil had as main components α-pinene (130%), sabinene (50%) and limonene (10.0%), whereas in the oil from the fruits, α-pinene (42.7%), sabinene (28.3%), and limonene (9.0%) were found to be themost important ones. © 1998, Taylor & Francis Group, LLC. All rights reserved.

A 40% aqueous solution of sulfuric acid (0.5 mL) was added to a stirred solution of 3,3-dimethyl- 4-hydroxy-5-(2,2,3-trimethyl-3-cyclopentenyl)-pentan-2-one (1) (630 mg, 2.65 mmol) in methanol (5 mL) and the mixture refluxed for 1.5 h.[...]

Sodium (241 mg, 10.48 mmol) was added to absolute ethanol (40 mL) and the mixture refluxed until sodium reacted completely.

p-Toluenesulfonic acid (48 mg, 0.25 mmol) was added to a stirred mixture of ethyl 2-methyl-acetoacetate (1) (346 mg, 2.40 mmol) and a-methylbenzylamine (2) (358 mg, 2.95 mmol) in toluene (13 mL) [1].[...]

p-Toluenesulfonic acid (35 mg, 0.20 mmol) was added to a stirred mixture of campholenic aldehyde (1) (725 mg, 3.81 mmol) and p-toluenesulfonamide (1.22 g, 6.96 mmol) in toluene (20 mL).[...]

To a stirred solution of a mixture of E/Z isomers 1 (81 mg, 0.22 mmol, 45:55 ratio) in acetone (5 mL) was added a mixture of KMnO4 (122 mg, 0.77 mmol) and anhydrous MgSO4 (120 mg) at 10 oC [1].[...]

Acetic anhydride (0.53 mL, 5.61 mmol) and N,N-dimethylaminopyridine (17 mg, 0.14 mmol) were added to a stirred solution of the alcohol 1 (442 mg, 1.31 mmol) in freshly distilled triethylamine (1.3 mL) [1].[...]

A sample (0.85 mL, 6.5 mmol) of formic acid-acetic anhydride mixture (FAM), prepared from Ac2O and formic acid as described in the literature [1], was added to the alcohol 1 [2](255 mg, 0.79 mmol) at 10 oC.[...]

A sample (0.03 mL, 0.45 mmol) of formic acid-acetic anhydride mixture (FAM), prepared from Ac2O and formic acid as described in the literature [1], was added to the alcohol 1 [2] (29 mg, 0.09 mmol) at 10 oC.[...]

To a stirred solution of a mixture of E/Z isomers 1 (174 mg, 0.52 mmol, 45:55 ratio) in acetone (8 mL) was added a mixture of KMnO4 (260 mg, 1.64 mmol) and anhydrous MgSO4 (230 mg) at 10 oC [1].[...]

This review summarizes the chemical composition reported up to date on Laurus nobilis L. (Lauraceae), an evergreen shrub or tree cultivated for its aromatic leaves and ornamental interest. It has been focused on non-volatile phytochemicals such as sesquiterpene lactones, flavonoids and proanthocyanidins, among others. Moreover, biological activities of laurel extracts and pure compounds have also been reviewed.