Leaf Extract from European Olive (Olea europaea L.) Post-Transcriptionally Suppresses the Epithelial-Mesenchymal Transition and Sensitizes Gastric Cancer Cells to Chemotherapy.

The overall survival of patients with the advanced and recurrent gastric cancer (GC) remains unfavorable. In particular, this is due to cancer spreading and resistance to chemotherapy associated with the epithelial-mesenchymal transition (EMT) of tumor cells. EMT can be identified by the transcriptome profiling of GC for EMT markers. Indeed, analysis of the TCGA and GTEx databases (n = 408) and a cohort of GC patients (n = 43) revealed that expression of the CDH2 gene was significantly decreased in the tumors vs. non-tumor tissues and correlated with the overall survival of GC patients. Expression of the EMT-promoting transcription factors SNAIL and ZEB1 was significantly increased in GC. These data suggest that targeting the EMT might be an attractive therapeutic approach for patients with GC. Previously, we demonstrated a potent anti-cancer activity of the olive leaf extract (OLE). However, its effect on the EMT regulation in GC remained unknown. Here, we showed that OLE efficiently potentiated the inhibitory effect of the chemotherapeutic agents 5-fluorouracil (5-FU) and cisplatin (Cis) on the EMT and their pro-apoptotic activity, as was demonstrated by changes in the expression of the EMT markers (E- and N-cadherins, vimentin, claudin-1) in GC cells treated with the aforementioned chemotherapeutic agents in the presence of OLE. Thus, culturing GC cells with 5-FU + OLE or Cis + OLE attenuated the invasive properties of cancer cells. Importantly, upregulation of expression of the apoptotic markers (PARP cleaved form) and increase in the number of cells undergoing apoptosis (annexin V-positive) were observed for GC cells treated with a combination of OLE and 5-FU or Cis. Collectively, our data illustrate that OLE efficiently interferes with the EMT in GC cells and potentiates the pro-apoptotic activity of certain chemotherapeutic agents used for GC therapy.

The hepatoprotective potentials of Olea europaea L. leaves against carbon tetrachloride-induced hepatic injury in rats.

OBJECTIVE: To examine the therapeutic effects of Olea europaea L. leaves extract on carbon tetrachloride-induced liver injury in rats. Methods: The experimental study was conducted at the Department of Physiology, University of Karachi, Karachi, in July 2021, and comprised Albino Wistar male rats weighing 180-220gm. The animals were divided into control group I, carbon tetrachloride group II, Olea europaea L. + carbon tetrachloride group III and Olea europaea L. group IV. In Vitro model of hepatic toxicity was developed by carbon tetrachloride. A daily dose of 50mg/kg of aqueous extract of olive leaves was administered orally and 0.8ml/kg of carbon tetrachloride was administered twice a week subcutaneously for 28 days. On the 29th day, the animals were sacrificed, and tested for hepatic enzymes, lipid peroxidation markers and histopathology. Data was analysed using SPSS 20. RESULTS: Of the 24 rats, 6(25%) were in each of the 4 groups. Alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and total bilirubin levels were significantly reduced (p<0.05) in group II whereas, 4- hydroxynonenal, isoprostane and malondialdehyde levels were significantly increased (p<0.05). However, total antioxidant level increased significantly (p<0.05) in group III compared to group II. Histopathology showed severe liver damage in group II and mild damage in group III. Conclusion: Olea europaea L. leaves extract was found to have profound hepatoprotective effects.

Highly Efficient Verbascoside Production from Olive (Olea europea L. var. Cellina di Nardò) In Vitro Cell Cultures.

Olive (Olea europea L.) is one of the oldest and most important fruit tree species cultivated in the Mediterranean region. Various plant tissues, drupes, and olive oil contain several phenolics (including verbascoside, although it is present in the plant at a low level) that are well-known for their highly beneficial effects on human health. An in vitro olive cell suspension culture (cultivar Cellina di Nardò, "CdN") was established, characterized for its growth and morphological features. Furthermore, a vital and relatively uniform population of protoplasts was generated from the olive suspension culture to investigate their cellular characteristics during growth. The polyphenolic extract of the in vitro "CdN" olive cells contained almost exclusively verbascoside, as revealed by the UPLC-ESI-MS analysis. The content of verbascoside reached up to 100 mg/g DW, with an average production rate of approximately 50 mg/g DW over one year of culture. This level of production has not been previously reported in a limited number of previous studies. This remarkable production of verbascoside was associated with an exceptionally high antioxidant capacity. The high level of verbascoside production and purity of the extract make this system a promising tool for secondary metabolite production.

Olive pectin-chitosan nanocomplexes for improving stability and bioavailability of blueberry anthocyanins.

Blueberry anthocyanins (ANCs) are natural dietary bioactive colorants, but are unstable and easily degraded. To improve their stability, we constructed the nanocarriers for ANCs through an electrostatic self-assembly method, using chitosan (CS) and olive pectin (PC). Results showed that the CS-ANCs-PC nanocomplexes had nanoscale particle size (81.22 ± 0.44 nm), and an encapsulation efficiency of 91.97 ± 0.33% at pH 3.0, 1:1:5 ratio (m/v) of CS: ANCs: PC. Fourier transform infrared and UV-visible spectra demonstrated that ANCs can be embedded into the CS-PC carrier through electrostatic interaction. CS-ANCs-PC with stacked spherical particle structure had good thermal stability by scanning electron microscope and thermogravimetric analysis. Compared with free anthocyanins, CS-ANCs-PC possessed better DPPH· and ·OH scavenging activities, stronger environmental stability, and better targeted release in vitro digestion. This study may provide an important fundamental basis for improving the stability of anthocyanins in the blueberry industry.

Continuous Production of Dietetic Structured Lipids Using Crude Acidic Olive Pomace Oils.

Crude olive pomace oil (OPO) is a by-product of olive oil extraction. In this study, low-calorie structured triacylglycerols (TAGs) were produced by acidolysis of crude OPO with medium-chain fatty acids (caprylic, C8:0; capric, C10:0) or interesterification with their ethyl ester forms (C8EE, C10EE). These new TAGs present long-chain fatty acids (L) at position sn-2 and medium-chain fatty acids (M) at positions sn-1,3 (MLM). Crude OPO exhibited a high acidity (12.05-28.75% free fatty acids), and high contents of chlorophylls and oxidation products. Reactions were carried out continuously in a packed-bed bioreactor for 70 h, using sn-1,3 regioselective commercial immobilized lipases (Thermomyces lanuginosus lipase, Lipozyme TL IM; and Rhizomucor miehei lipase, Lipozyme RM IM), in solvent-free media at 40 °C. Lipozyme RM IM presented a higher affinity for C10:0 and C10EE. Lipozyme TL IM preferred C10:0 over C8:0 but C8EE over C10EE. Both biocatalysts showed a high activity and operational stability and were not affected by OPO acidity. The New TAG yields ranged 30-60 and the specific productivity ranged 0.96-1.87 g NewTAG/h.g biocatalyst. Lipozyme RM IM cost is more than seven-fold the Lipozyme TL IM cost. Therefore, using Lipozyme TL IM and crude acidic OPO in a continuous bioreactor will contribute to process sustainability for structured lipid production by lowering the cost of the biocatalyst and avoiding oil refining.

Analysis of Antioxidant and Antiviral Effects of Olive (Olea europaea L.) Leaf Extracts and Pure Compound Using Cancer Cell Model.

The present study aims to assess the antioxidant and antiviral effectiveness of leaf extracts obtained from Olea europaea L. var. sativa and Olea europaea L. var. sylvestris. The total antioxidant activity was determined via both an ammonium phosphomolybdate assay and a nitric oxide radical inhibition assay. Both extracts showed reducing abilities in an in vitro system and in human HeLa cells. Indeed, after oxidative stress induction, we found that exposition to olive leaf extracts protects human HeLa cells from lipid peroxidation and increases the concentration of enzyme antioxidants such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase. Additionally, OESA treatment affects viral DNA accumulation more than OESY, probably due to the exclusive oleuropein content. In fact, subtoxic concentrations of oleuropein inhibit HSV-1 replication, stimulating the phosphorylation of PKR, c-FOS, and c-JUN proteins. These results provide new knowledge about the potential health benefits and mechanisms of action of oleuropein and oleuropein-rich extracts.

Phytochemicals from Red Onion, Grown with Eco-Sustainable Fertilizers, Protect Mammalian Cells from Oxidative Stress, Increasing Their Viability.

Red onion, a species of great economic importance rich in phytochemicals (bioactive compounds) known for its medicinal properties, was fertilized with sulphur-bentonite enriched with orange residue or olive pomace, with the aim of producing onion enriched in health beneficial compounds. There is a worldwide great demand of minimally processed food or food ingredients with functional properties because of a new awareness of how important healthy functional nutrition is in life. Phytochemicals have the capacity to regulate most of the metabolic processes resulting in health benefits. Red onion bioactive compound quantity and quality can vary according to cultivation practices. The main aims of the current research were to determine the chemical characteristics of the crude extracts from red onion bulbs differently fertilized and to evaluate their biological activity in normal and oxidative stress conditions. The lyophilized onion bulbs have been tested in vitro on two cellular models, i.e., the H9c2 rat cardiomyoblast cell line and primary human dermal fibroblasts, in terms of viability and oxygen radical homeostasis. The results evidenced different phytochemical compositions and antioxidant activities of the extracts obtained from red onions differently fertilized. Sulphur-bentonite fertilizers containing orange waste and olive pomace positively affected the red onion quality with respect to the red onion control, evidencing that sulphur-bentonite-organic fertilization was able to stimulate plant a secondary metabolism inducing the production of phytochemicals with healthy functions. A positive effect of the extracts from red onions treated with fertilizers-in particular, with those containing orange waste, such as the reduction of oxidative stress and induction of cell viability of H9c2 and human fibroblasts-was observed, showing a concentration- and time-dependent profile. The results evidenced that the positive effects were related to the phenols and, in particular, to chlorogenic and p-coumaric acids and to the flavonol kaempferol, which were more present in red onion treated with low orange residue than in the other treated ones.

Prophylactic role of olive fruit extract against cigarette smoke-induced oxidative stress in Sprague-Dawley rats.

Cigarette smoke exposure increases the production of free radicals leading to initiation of several pathological conditions by triggering the oxidative stress and inflammatory cascade. Olive fruit owing to its unique phytochemical composition possesses antioxidant, immune modulatory, and anti-inflammatory potential. Considering the compositional alterations in olive fruits during ripening, the current experimental trail was designed to investigate the prophylactic role of green and black olives against the oxidative stress induced by cigarette smoke exposure in rats. Purposely, rats were divided into five different groups: NC (negative control; normal diet), PC [positive control; normal diet + smoke exposure (SE)], drug (normal diet + SE + citalopram), GO (normal diet + SE + green olive extract), and BO (normal diet + SE + black olive extract). Rats of all groups were exposed to cigarette smoke except "NC" and were sacrificed for collection of blood and organs after 28 days of experimental trial. The percent reduction in total oxidative stress by citalopram and green and black olive extracts in serum was 29.72, 58.69, and 57.97%, respectively, while the total antioxidant capacity increased by 30.78, 53.94, and 43.98%, accordingly in comparison to PC. Moreover, malondialdehyde (MDA) was reduced by 29.63, 42.59, and 45.70% in drug, GO, and BO groups, respectively. Likewise, green and black olive extracts reduced the leakage of hepatic enzymes in sera, alkaline phosphatase (ALP) by 23.44 and 25.80% and 35.62 and 37.61%, alanine transaminase (ALT) by 42.68 and 24.39% and 51.04 and 35.41%, and aspartate transaminase (AST) by 31.51 and 16.07% and 40.50 and 27.09% from PC and drug group, respectively. Additionally, olive extracts also maintained the antioxidant pool, i.e., superoxide dismutase, catalase, and glutathione in serum. Furthermore, histological examination revealed that olive extracts prevented the cigarette smoke-induced necrosis, pyknotic alterations, and congestion in the lung, hepatic, and renal parenchyma. Besides, gene expression analysis revealed that olive extracts and citalopram decreased the brain and lung damage caused by stress-induced upregulation of NRF-2 and MAPK signaling pathways. Hence, it can be concluded that olives (both green and black) can act as promising antioxidant in alleviating the cigarette smoke-induced oxidative stress.

Impact of fresh olive leaves addition during the extraction of Arbequina virgin olive oils on the phenolic and volatile profiles.

Leaves incorporation during the extraction of olive oils can enhance their chemical-sensory quality. Thus, leaves from cvs. Arbequina or Santulhana were added (1%, w/w) during the extraction of Arbequina oils using an Abencor system, being discussed the impacts on the phenolics and volatiles formation enzymatic pathways. Leaves addition contributed to a significant decrease (P-value < 0.05) of the contents of secoiridoids (-11%), C6-aldehydes (-16%), and ester compounds (-22%). This could be tentatively related to a reduction of the enzymatic activity of secoiridoids biosynthesis and lipoxygenase pathways, promoted by the leaves' addition. Moreover, in the presence of leaves, the oils' total contents of phenolics and volatiles were significantly reduced (-7 and -17%, respectively). Contrary, the incorporation of leaves significantly increased (P-value < 0.05) the contents of C6-alcohols (+37%) and the intensities of the green fruity (+25%) and apple (+30%) sensations.

Immunotherapeutic potential of ethanolic olive leaves extract (EOLE) and IL-28B combination therapy in ENU induced animal model of leukemia.

Cytokine therapies have shown promising results against cancers. Cytokines are secreted naturally from different bodily cells. These have fewer side effects but higher specificity than chemotherapy and radiation therapy. In leukemia, changes in normal hematopoiesis and defective leukocyte production limit the efficacy of immunotherapy by reducing the count of functional immune cells. Therefore, the treatment of leukemia needs advanced therapeutics that can target multiple cancer sustaining mechanisms. In combination therapy, using two different therapeutic agents affect cancer growth in many ways and sometimes gives synergistic effects. Here, we examined the effect of the ethanolic olive leaf extract (EOLE) and IL-28B in combination. N-N' Ethyl-nitrosourea (ENU) induced leukemia in Swiss albino mice was treated with EOLE for four weeks and IL-28B for one week after confirming the development of leukemia. The combination of EOLE and IL-28B significantly reduced the blast cell and total WBC counts in the peripheral blood, altered the levels of various cytokines in plasma, and induced the functional activity of NK cells in leukemic mice. The induced NK activity correlates with increased expression of perforin and granzyme studied at the gene level through real-time (RT)-PCR. The treatment of leukemic mice with combined EOLE and IL-28B has also caused an increased serum IL-10 and IFN-γ level, and reduced serum TGF-ß indicates improved overall immunity. Altogether, the combination of EOLE and IL-28B has given substantial therapeutic activity against leukemia.

Oleuropein-Rich Olive Leaf Extract Attenuates Neuroinflammation in the Alzheimer's Disease Mouse Model.

Alzheimer's disease (AD) is the most common form of dementia among several neurodegenerative disorders afflicting the elderly. AD is characterized by the deposition of extracellular amyloid-ß (Aß) plaques, disrupted blood-brain barrier (BBB), and neuroinflammation. Several studies have demonstrated the health benefits of olive oil and olive leaf extract (OLE) due to their polyphenolic content. The main phenolic compound in OLE is glycosylated oleuropein (OLG), while the aglycon form of oleuropein (OLA) exists in much lower amounts. This work aimed to evaluate the effect of a low dose of OLG-rich OLE and the mechanism(s) that contributed to the observed beneficial effects against Aß pathology in the homozygous 5xFAD mouse model. Mice were fed with OLE-enriched diet (695 µg/kg body weight/day) for 3 months, starting at 3 months old. Overall findings demonstrated that OLE reduced neuroinflammation by inhibiting the NF-κB pathway and suppressing the activation of NLRP3 inflammasomes and RAGE/HMGB1 pathways. In addition, OLE reduced total Aß brain levels due to increased clearance and reduced production of Aß and enhanced BBB integrity and function, which collectively improved the memory function. Thus, the consumption of OLE as a dietary supplement is expected to stop and/or slow the progression of AD.

Integrated bioprocess for structured lipids, emulsifiers and biodiesel production using crude acidic olive pomace oils.

Olive pomace oil (OPO), a by-product of olive oil industry, is directly consumed after refining. The novelty of this study consists of the direct use of crude high acidic OPO (3.4-20% acidity) to produce added-value compounds, using sn-1,3-regioselective lipases: (i) low-calorie dietetic structured lipids (SL) containing caprylic (C8:0) or capric (C10:0) acids by acidolysis or interesterification with their ethyl esters, (ii) fatty acid methyl esters (FAME) for biodiesel, and (iii) sn-2 monoacylglycerols (emulsifiers), as by-product of FAME production by methanolysis. Immobilized Rhizomucor miehei lipase showed similar activity in acidolysis and interesterification for SL production (yields: 47.8-53.4%, 7 h, 50℃) and was not affected by OPO acidity. Batch operational stability decreased with OPO acidity, but it was at least three-fold in interesterification that in acidolysis. Complete conversion of OPO into FAME and sn-2 monoacylglycerols was observed after 3 h-transesterification (glycerol stepwise addition) and lipase deactivation was negligeable after 11 cycles.

Effects of pomegranate peel and olive pomace supplementation on reproduction and oxidative status of rabbit doe.

The current study aimed to investigate the effects of pomegranate peel and olive pomace supplementation on the reproductive hormones, antioxidative status, reproductive capacity and maternal behaviour of rabbit does. Forty does were used for the experiments. The animals were randomly assigned to four groups of ten does. One group was fed on the control diet and was considered the control group (C). The second group was supplemented with 4.5% pomegranate peel in their diet (P), the third group was supplemented with 10% olive pomace in their diet (O), and the fourth group was supplemented with a mixture of pomegranate peel and olive pomace (PO). Compared with the control does, group P showed significantly increased serum levels of gonadotropic hormones and oestradiol-17ß two hours after mating, on the 20th day of lactation and after weaning; significantly increased progesterone levels at mid-pregnancy; and significantly increased in prolactin levels on the 10th day of lactation. Additionally, the results revealed significant increases in total DNA, protein concentration, litter size, milk yield and nest traits of groups P and PO. In conclusion, pomegranate peel supplementation improves the reproductive performance of does and increases their antioxidant parameters.

Can fig and olive ameliorate the toxicity induced by 2-nitropropane in some organs of mice? Role of inflammatory versus anti-inflammatory gene.

OBJECTIVE: To investigate the efficacy of Fig fruit powder and olive on hepatic, renal and splenic injury induced by 2-nitropropane (2-NP) in mice, especially if they were used in combination. METHODS: A total of 40 adult BALB/c male mice weighting 25-30 g/each. Mice were categorized into five groups (8 each). Group 1 as negative control. Group 2 as positive control group intraperitoneally injected with 2-NP (100 mg/kg b. w.) 3 times/weekly for eight weeks. Group 3 injected with 2-NP and were orally supplemented with Fig (300 mg/kg). Group 4 injected with 2-NP and were orally supplemented with olive (100 mg/kg). Group 5 injected with 2-NP and were orally supplemented with mixture of Fig and olive (3:1 respectively). RESULTS: Histopathological observation of liver in mice treated with 2-NP showed cellular degeneration, pyknosis, and congestion of the portal vein. In kidney there were disorganization of the cortical tissues, cellular necrosis and plenty of inflammatory lymphocytic aggregation. Significant elevations in liver function parameters (alanine aminotransferase and aspartate aminotransferase), mRNA expression levels of tumor necrosis factor-α, nicotinamide adenine dinucleotide phosphate oxidase and cyclooxygenase were detected as anti-inflammatory markers and 5-lipoxygenase, interleukin-1α and interleukin-6 as inflammatory biomarkers for liver and spleen, also significant elevations was detected in lipid peroxidation levels. The levels of antioxidants, glutathione, glutathione peroxidase, catalase and superoxide dismutase were significantly decreased. CONCLUSION: our findings indicated that Fig fruit powder and olive protected against hepatic, renal and splenic injury induced with 2-NP in mice, especially if they were used in combination.

Olea europaea Suppresses Inflammation by Targeting TAK1-Mediated MAP Kinase Activation.

Possessing a variety of medicinal functions, Olea europaea L. is widely cultivated across the world. However, the anti-inflammatory mechanism of Olea europaea is not yet fully elucidated. In this study, how the methanol extract of the leaves of Olea europaea (Oe-ME) can suppress in vitro inflammatory responses was examined in terms of the identification of the target protein. RAW264.7 and HEK293T cells were used to study macrophage-mediated inflammatory responses and to validate the target protein using PCR, immunoblotting, nuclear fraction, overexpression, and cellular thermal shift assay (CETSA) under fixed conditions. Oe-ME treatment inhibited the mRNA expression levels of cyclooxygenase (COX)-2, matrix metallopeptidase (MMP)-9, and intercellular adhesion molecule-1 (ICAM-1) in activated RAW264.7 cells. Oe-ME diminished the activation of activator protein (AP)-1 and the phosphorylation of its upstream signaling cascades, including extracellular signal regulated kinase (ERK), mitogen-activated protein kinase kinase 1/2 (MEK1/2), c-Jun N-terminal kinase (JNK), mitogen-activated protein kinase kinase 3/6 (MKK3/6), p38, MKK7, and transforming growth factor-ß-activated kinase 1 (TAK1), in stimulated-RAW264.7 cells. Overexpression and CETSA were carried out to verify that TAK1 is the target of Oe-ME. Our results suggest that the anti-inflammatory effect of Oe-ME could be attributed to its control of posttranslational modification and transcription of TAK1.

Micronization increases the bioaccessibility of polyphenols from granulometrically separated olive pomace fractions.

The effect of micronization of granulometrically fractionated olive pomace (OP) on the bioaccessibility of polyphenols and the antioxidant capacity was investigated during sequential in vitro static digestion. Crude OP was fractionated in a 2-mm sieve (F1: > 2 mm; F2: < 2 mm) and then micronized (300 r min-1, 5 h) generating F1AG (17.8 µm) and F2AG (15.6 µm). Micronization increased the release of hydroxytyrosol, oleuropein, caffeic acid, and decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA) in the salivary and gastric phase, beyond luteolin in the gastric phase. Micronization also increased the intestinal bioaccessibility of hydroxytyrosol, 3,4-DHPEA-EDA, oleuropein, luteolin, and apigenin; it was more effective for F2AG than F1AG. Micronized samples increased antioxidant capacity in the gastric phase. F2AG exhibited the highest antioxidant capacity in the insoluble intestinal fraction. Thus, micronization can be further exploited to improve the nutraceutical properties of OP by increasing the bioaccessibility and antioxidant capacity of phenolic compounds.

Olive Pâté by Multi-Phase Decanter as Potential Source of Bioactive Compounds of Both Nutraceutical and Anticancer Effects.

In the oil sector, a novelty in the centrifugal extraction system is represented by the multi-phase decanters (DMF) that work without adding process water and with the advantage of recovering a dried pomace and a by-product, called "pâté", consisting of the pulp and its vegetation water, without traces of stone. The pâté has a high content of phenolic compounds, mainly represented by secoiridoids and verbascoside. The present work investigated the efficacy of two different ways of debittering (by sequential filtrations and spontaneous fermentation) of DMF pâté from three olive cultivars (Olea europaea L. "Leccino", "Carboncella" and "Tortiglione") to make the pâté edible, and, contemporary, investigated also the effect of its phenolic bioactive extracts on pathogenic bacteria and colon cancer cell model. Daily filtrations of pâté of the three cultivars have been shown to be more efficient in phenolic degradation. The activity of the indigenous microflora on the other hand takes a longer time to degrade the phenolic component and therefore to de-bitter it. None of pâté showed antibacterial activity. Colorimetric assay MTS for cell viability and metabolic activity tested on colon cancer cells CaCo2 and HCT116 suggest a potential beneficial effect of the dried extracts probably related to the modulation of gene expression under these treatments.

Antiproliferative and Pro-Apoptotic Effect of Uvaol in Human Hepatocarcinoma HepG2 Cells by Affecting G0/G1 Cell Cycle Arrest, ROS Production and AKT/PI3K Signaling Pathway.

Natural products have a significant role in the development of new drugs, being relevant the pentacyclic triterpenes extracted from Olea europaea L. Anticancer effect of uvaol, a natural triterpene, has been scarcely studied. The aim of this study was to understand the anticancer mechanism of uvaol in the HepG2 cell line. Cytotoxicity results showed a selectivity effect of uvaol with higher influence in HepG2 than WRL68 cells used as control. Our results show that uvaol has a clear and selective anticancer activity in HepG2 cells supported by a significant anti-migratory capacity and a significant increase in the expression of HSP-60. Furthermore, the administration of this triterpene induces cell arrest in the G0/G1 phase, as well as an increase in the rate of cell apoptosis. These results are supported by a decrease in the expression of the anti-apoptotic protein Bcl2, an increase in the expression of the pro-apoptotic protein Bax, together with a down-regulation of the AKT/PI3K signaling pathway. A reduction in reactive oxygen species (ROS) levels in HepG2 cells was also observed. Altogether, results showed anti-proliferative and pro-apoptotic effect of uvaol on hepatocellular carcinoma, constituting an interesting challenge in the development of new treatments against this type of cancer.

New Strategies in the Cultivation of Olive Trees and Repercussions on the Nutritional Value of the Extra Virgin Olive Oil.

The health advantages of extra-virgin olive oil (EVOO) are ascribed mainly to the antioxidant ability of the phenolic compounds. Secoiridoids, hydroxytyrosol, tyrosol, phenolic acid, and flavones, are the main nutraceutical substances of EVOO. Applications of beneficial microbes and/or their metabolites impact the plant metabolome. In this study the effects of application of selected Trichoderma strains or their effectors (secondary metabolites) on the phenolic compounds content and antioxidant potential of the EVOOs have been evaluated. For this purpose, Trichoderma virens (strain GV41) and Trichoderma harzianum (strain T22), well-known biocontrol agents, and two their metabolites harzianic acid (HA) and 6-pentyl-α-pyrone (6PP) were been used to treat plants of Olea europaea var. Leccino and var. Carolea. Then the nutraceutical potential of EVOO was evaluated. Total phenolic content was estimated by Folin-Ciocalteau's assay, metabolic profile by High-Resolution Mass spectroscopy (HRMS-Orbitrap), and antioxidant activity by DPPH and ABTS assays. Our results showed that in the cultivation of the olive tree, T22 and its metabolites improve the nutraceutical value of the EVOOs modulating the phenolic profile and improving antioxidants activity.

Lipid Composition and Associated Gene Expression Patterns during Pollen Germination and Pollen Tube Growth in Olive (Olea europaea L.).

Pollen lipids are essential for sexual reproduction, but our current knowledge regarding lipid dynamics in growing pollen tubes is still very scarce. Here, we report unique lipid composition and associated gene expression patterns during olive pollen germination. Up to 376 genes involved in the biosynthesis of all lipid classes, except suberin, cutin and lipopolysaccharides, are expressed in olive pollen. The fatty acid profile of olive pollen is markedly different compared with other plant organs. Triacylglycerol (TAG), containing mostly C12-C16 saturated fatty acids, constitutes the bulk of olive pollen lipids. These compounds are partially mobilized, and the released fatty acids enter the ß-oxidation pathway to yield acetyl-CoA, which is converted into sugars through the glyoxylate cycle during the course of pollen germination. Our data suggest that fatty acids are synthesized de novo and incorporated into glycerolipids by the 'eukaryotic pathway' in elongating pollen tubes. Phosphatidic acid is synthesized de novo in the endomembrane system during pollen germination and seems to have a central role in pollen tube lipid metabolism. The coordinated action of fatty acid desaturases FAD2-3 and FAD3B might explain the increase in linoleic and alpha-linolenic acids observed in germinating pollen. Continuous synthesis of TAG by the action of diacylglycerol acyltransferase 1 (DGAT1) enzyme, but not phosphoplipid:diacylglycerol acyltransferase (PDAT), also seems plausible. All these data allow for a better understanding of lipid metabolism during the olive reproductive process, which can impact, in the future, on the increase in olive fruit yield and, therefore, olive oil production.