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For the efficient conversion of L-tyrosine (L-Tyr) to tyrosol, which is an aromatic compound widely used in the pharmaceutical and chemical industries, a novel four-enzyme cascade pathway based on the Ehrlich pathway of Saccharomyces cerevisiae was designed and reconstructed in Escherichia coli. Then, the expression levels of the relevant enzymes were coordinated using a modular approach and gene duplication after the identification of the pyruvate decarboxylase from Candida tropicalis (CtPDC) as the rate-limiting enzymatic step. In situ product removal (ISPR) strategy with XAD4 resins was explored to avoid product inhibition and further improve tyrosol yield. As a result, the titer and conversion rate of tyrosol obtained were 35.7 g·L-1 and 93.6%, respectively, in a 3-L bioreactor. Results presented here provide a potential enzymatic process for industrial production of tyrosol from cheap amino acids.

Salidroside (8-O-β- d -glucoside of tyrosol), a plant-derived natural product, is used for treatment of hypoxia, fatigue and aging diseases. The availability of salidroside is restricted since it is extracted from 3-5 years old Rhodiola roots, which grow very slowly in the cold region of northern hemisphere of Earth. Our laboratory has constructed an engineered Escherichia coli and established a fermentation process to produce salidroside from glucose. In this article, nine macroporous resins from polarity to non-polarity, including NKA-9, S-8, AB-8, SP825, D101, LSA-8, LX-12, LX-18 and LX-68 resins, were tested to separate salidroside from fermentation broth. After static and dynamic experiments, the weakly polar SP825 resin had a better separation efficiency among nine resins. The adsorption kinetic and isotherm of salidroside on the SP825 resin were determined, and the pseudo-second-order kinetic model and Langmuir model could be fitted well. The effects of the pH on adsorption and ethanol concentration on desorption were investigated, and an optimal separation process was established. The adsorption for salidroside in the SP825 resin column was conducted with loading 150 ml at pH 7, and desorpted by washing 50 ml of 80% ethanol solution. Under the best process conditions, the purity and yield of salidroside in the final product were 91.6% and 74.0%, respectively. The results showed that the macroporous SP825 resin would be feasible and effective to prepare salidroside and has promising application in the downstream process of microbial fermentation. © 2020 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd.. All rights reserved.

A variety of glycosides with interesting biological properties suitable for application in cosmetic and pharmaceutical industry can be found in nature. However, the demand exceeds the quantity and purity which can be obtained naturally and therefore enzymatic glycosylation has been of great interest in recent decades. In this study, crude Kluyveromyces lactis enzyme preparation Lactozym 3000 L was examined for the production of two phenolic glycosides – tyrosol β-fructoside and tyrosol β-galactoside. Its performance was compared to other commercial fungal and yeast enzyme preparations. It was found that the key enzyme, β-galactosidase is unsuitable for tyrosol β-galactoside production. However, one of the Lactozym 3000 L components, β-fructofuranosidase, performed very well in the tyrosol β-fructoside production from sucrose and tyrosol. Lactozym 3000 L was effectively immobilized onto activated carrier Lifetech ECR8309 via covalent binding of the enzyme, which is a promising method to reduce very high enzyme consumption in its free form. Potential of deep-eutectic solvents to enhance transfructosylation selectivity has been studied proving their interesting stabilization effect on Lactozym 3000 L β-fructofuranosidase.

Wastewater from the olive mill constitutes a serious environmental concern, as it is characterized by a high inorganic and organic load. Here, a hybrid photocatalyst based on calcined Ca-Fe–LDH was successfully synthesized for the degradation of phenolic compounds and the removal of chemical oxygen demand (COD) from the high-strength olive mill wastewater (OMW). The catalyst (CuCr2O4@CaFe–LDO) displayed a stable ~4.48 µA cm−2 photocurrent response, a 2.56 eV bandgap and a wide variety of pores with an average size of 12.51 nm. 1.0 g CuCr2O4@CaFe–LDO achieved 66% COD removal after 300 mins without an oxidant in the dark, while after 180 mins of reaction, CuCr2O4@CaFe–LDO/K2S2O8/sunlight system resulted in ~99% and 98.3% COD and colour removal. Seven phenolic compounds were found in the crude OMW, with hydroxytyrosol (76.84%) and tyrosol (15.14%) being the main ones. The final pH of the sample treated increased from 4.3 to 7.3, which confirmed the degradation of phenolics and fatty acids in the OMW. OH, SO4−, h+ and O2− contributed notably to the degradation of polyphenols and the spent catalyst was easily and rapidly recovered from the bulk solution due to its saturation magnetization of 54.7 emu g−1.

Honey varies depending on plant origin and environmental conditions. Chemical constituents can be used to determine the origins, characteristics, and storage period of a specific honey. Styrax japonica (snowbell) honey has excellent flavor, but very few studies have been carried out on its chemical constituents. Therefore, the present study was aimed to identify chemical constituents containing in snowbell honey and to screen candidate marker compounds for predicting the storage period of snowbell honey using the identified compounds. Twelve compounds including three new compounds were purified and isolated from the snowbell honey. Three new compounds were elucidated as 1α,3β,5β-bornetriol, 7-hydroxy-2,2,6-trimethyl-1-oxaspiro[2.5]oct-5-en-4-one, and 2-benzyl-2,3-dihydroxybutanoic acid, based on ESI-MS and NMR experiments. 6,7-Dihydroxylinalool and 6,7-dihydroxygeraniol isolated as known compounds in this study were identified for the first time in snowbell honey as well as in other honeys. The isolated compounds were qualified and quantified by LC-ESI-Q-TOF-MS/MS analysis. All compounds were detected in snowbell honeys of different production years. The levels of tyrosol, 7-hydroxy-2,2,6-trimethyl-1-oxaspiro[2.5]oct-5-en-4-one, and (–)-dihydroxyphaseic acid were lower in snowbell honey with long storage period than in short storage period, which is suggested to be used as candidate marker compounds for predicting the storage period of snowbell honey.

Studies have revealed the antioxidant and antifungal activities of the metabolite tyrosol, a phenolic compound from olive oil and several endophytic fungi. The substance was isolated from the ethyl acetate extract of the endophytic fungus Phomopsis sp. and was described as a natural product (NP) with a potential biostimulant effect in soybean seed treatment. In this study, the application of an oil-based solution of tyrosol (10 mg/L) to soybean seeds showed no significant difference from soybean seeds without tyrosol in terms of germination percentage, number of nodules, number of seeds per plant, and number of pods per plant. Metabolomic analysis of the soybean leaves using GC–MS showed differences in the chemical composition between the treatments, with significant differences in the abundance of 11 metabolites. Among them, aspartic acid, which is a precursor to several essential amino acids, presented a positive effect under tyrosol application, and the analysis of the metabolic routes (MetaboAnalyst 4.0) indicated a significant improvement in the nitrogen metabolism pathway. The substances related to nitrogen translocation also behaved differently with the tyrosol treatment of seeds, with a negative effect on the concentrations of allantoin and urea, but a positive effect on aspartate. These results show that tyrosol changes soybean plant metabolism without significant effects on crop yield.

Aromatic alcohols, such as tyrosol and 2-phenylethanol, are widely used in various industries owing to their superior flavors and properties. In this study, a yeast metabolic modification platform for the de novo synthesis of tyrosol and 2-phenylethanol was established. Alleviation of the feedback inhibition and overexpression of 3-deoxy- d -arabino-heptulosonate-7-phosphate synthase and chorismate mutase were achieved by introducing aroGD146N and pheAfbr genes from Escherichia coli. Shikimate kinase (aroL) and shikimate dehydrogenase (ydiB), analogues of the penta-functional enzyme Aro1p, were overexpressed to release the metabolic bottlenecks. Furthermore, in addition to ARO10-overexpression, ARO9 was disrupted to reduce the by-product generation. Finally, by introducing EcaroGD146N, EcpheAfbr, EcydiB and EcaroL in the ARO9-deleted strain, together with overexpression of transketolase (TKL1) and phenylpyruvate decarboxylase (ARO10), the engineered strain JM26 was constructed. Using glucose as the sole carbon source, JM26 achieved 541 mg/L (73.5 mg/g DCW) of tyrosol and 643 mg/L (92.0 mg/g DCW) of 2-phenylethanol, which is 5.7-fold and 6.1-fold higher than the control strain, respectively. These results demonstrate that the strategies applied improved de novo production of tyrosol and 2-phenylethanol, and showed potential for application as a metabolic chassis for other aromatic compounds in Saccharomyces cerevisiae and the exploration of their biological functions.

Olive mill wastewater (OMW) is a by-product generated from olive oil extraction systems. It contains high concentrations of organic compounds mainly phenols which cause environmental problems for the ecosystem, such as soil contamination and water pollution. Therefore, treatment of OMW is very much needed. Some of the naturally present chemicals in OMW have a positive economic value. In this investigation, liquid/liquid extraction using ethyl acetate (EA) as a solvent to recover such valuable compounds was investigated. Several parameters were studied namely, time of extraction, pH, EA/OMW volumetric ratio, and initial concentration of total phenols. Based on UHPLC analysis, hydroxytyrosol (HT) was the most abundant phenol in EA extracts from OMW. Many other phenols (tyrosol, oleuropein, p-coumaric acid, syringic acid, and 4-hydroxybinzoic acid) were also identified. Percentage recovery of HT reached 62 % after 2 h of extraction, at an EA/OMW ratio of 2/1 (v/v) and a pH of 2. Distribution coefficient of HT in EA was evaluated and was found to be around 0.8. The above process is envisioned to ultimately produce clean water which may be used in irrigation or in olive mills in a sustainable way. In addition, the extract is expected to have a high economic value.

3 Figuras.-- 4 Tablas, The application of thermal pretreatments to facilitate its anaerobic digestion has associated phenols and furans production, which are commonly identified as inhibitory compounds. Phenols and furans extraction can be done from a liquid phase produced after the thermal pretreatment. In the present study this dephenolized liquid phase (DLP) showed an increase of 42% in methane yield compared to the raw liquid phase (LP) demonstrating the inhibitor character of such compounds. The main extracted phenols and furans were: 3,4-Dihydroxyphenylglycol (DHPG), Hydroxytyrosol (HT), Tyrosol (Ty), Vanillic acid (AcV), Hydroxymethylfurfural (HMF), Vanillin (V) and Furfural (F).This study also aimed to evaluate the individual effect on methane production of these specific phenols and furans the within the mixture of several ones from LP. The evaluation of the individual compounds over the methanogenesis of a dephenolized liquid phase showed that only V was inhibitory on both methane yield and methane production rate. HMF had a significantly negative effect on methane yield, but improved the methane production rate instead. Ty, F, DHPG and HT favoured the methane yield and production rate. Additionally, it was observed that negative effect of some individual phenols and furans was counteracted by the positive effect of other compounds., This work was supported by the Asociación Universitaria Iberoamericana de Postgrado through the call Programa de Becas de Movilidad entre Universidades Andaluzas e Iberoamericanas 2017. The authors are also very grateful to the Spanish Ministry of Economy and Competitiveness for funding this research through the project CTM2014-55095-R. In addition, the authors are grateful to “Becas Chile: CONICYT-PFCHA/MagísterNacional/2017-22122499” and Universidad Técnica Federico Santa María by “DGIIP Project number PLI_18_26” and “Programa de Incentivos a la Iniciación Científica (PIIC)”, and São Paulo Research Foundation (FAPESP process 2019/21370-7).

The chemical investigation of the nonpolar constituents of a methanol extract of the bulbs of Boophone haemanthoides yielded ten known compounds as minor constituents. The compounds were identified as stigmast-4-ene-3,6-dione (1); cholest-4-en-3-one (2); (22E)-stigmast-4,22-dien-3-one (3); stigmast-4-en-3-one (4); 6β-hydroxystigmast-4-en-3-one (5); 6β-hydroxycholest-4-en-3-one (6); cycloartenol (7); acetovanillone (8); tyrosol (10) and 3-hydroxy-1-(4-hydroxyphenyl)-1-propanone (11). The isolation of compound 7 with other cholestane (2, 6) and stigmastane (1, 3–5) derivatives aligned with the biosynthetic pathway of plant steroids through 7 from squalene 2,3-epoxide. This is the first report on the isolation and identification of these compounds from B. haemanthoides and 1–6 and 11 for the family Amaryllidaceae.

The effect of mannoproteins on the evolution of rose sparkling wines during over-lees aging was investigated on the basis of the chemical characterization of polyphenols, organic acids, macro- and microelements using a combined analytical approach. Variations on these constituents were assessed using Raman and near-infrared spectroscopy. During the biological aging, caffeic acid, catechin, gallic acid and malvidin-3-O-glucoside were the most abundant polyphenolics in the rose wines. The phenolic compound tyrosol, a fermentation derivative, was found at concentrations up to 98.07 mg L−1. The addition of mannoproteins significantly affected the concentrations of organic acids and individual polyphenolic compounds, particularly trans-resveratrol, quercetin, catechin, p-coumaric and hydroxybenzoic acids that showed increased concentrations over time. The positive effects of mannoproteins were mainly observed at the end of the biological aging. The mineral composition remained stable, while potassium was the most abundant mineral in all wines. The observed changes involving these constituents may offer new insights on their behavior during wine aging and on the bioactive and nutritional quality of rose sparkling wines.

Parkinson's disease (PD) is a common neurodegenerative disorder involving α-synuclein (α-syn) aggregation, oxidative stress, dysregulation of redox metal homeostasis, and neurotoxicity. Different phenolic compounds with known antioxidant or antichelating properties have been shown to also interfere with aggregation of amyloid proteins and modulate intracellular signaling pathways. The present study aims to investigate for the first time the effect of tyrosol (TYR), a simple phenol present in extra-virgin olive oil, on α-syn aggregation in a Caenorhabditis elegans model of PD and evaluate its potential to prevent α-syn toxicity, neurodegeneration, and oxidative stress in this model organism. Our results show that TYR is effective in reducing α-syn inclusions, resulting in a lower toxicity and extended life span of treated nematodes. Moreover, TYR delayed α-syn-dependent degeneration of dopaminergic neurons in vivo. TYR treatment also reduced reactive oxygen species level and promoted the expression of specific chaperones and antioxidant enzymes. Overall, our study puts into perspective TYR potential to be considered as nutraceutical that targets pivotal causal factors in PD.

Olive mill wastewater (OMW) as a by-product of olive oil extraction process has significant polluting properties mainly related to high organic load, increased COD/BOD ratio, high phenolic content and relatively acidic pH. Raw OMW from Slovenian Istria olive oil mill and its polar fraction were investigated in this study. Chemical characterization of OMW polar fraction identified tyrosol as the most abundant phenolic product, followed by catechol. Lethal and sub-lethal effects of OMW matrix and its polar fraction were tested using a battery of bioassays with model organisms: bacteria Vibrio fischeri, algae Chlorella vulgaris, water fleas Daphnia magna, zebrafish Danio rerio embryos, clover Trifolium repens and wheat Triticum aestivum. Raw OMW sample was the most toxic to V. fischeri (EC50 = 0.24% of OMW sample final concentration), followed by D. magna (EC50 = 1.43%), C. vulgaris (EC50 = 5.20%), D. rerio (EC50 = 7.05%), seeds T. repens (EC50 = 8.68%) and T. aestivum (EC50 = 11.58%). Similar toxicity trend was observed during exposure to OMW polar fraction, showing EC50 values 2.75–4.11 times lower comparing to raw OMW. Tested samples induced also sub-acute effects to clover and wheat (decreased roots, sprouts elongation); and to zebrafish embryos (increased mortality, higher abnormality rate, decreased hatching and pigmentation formation rate). A comprehensive approach using a battery of bioassays, like those used in this study should be applied during ecotoxicity monitoring of untreated and treated OMW.

Roseroot (Rhodiola rosea L.) is a medicinal plant with adaptogenic properties and several pharmaceutically important metabolites. In this study, a full length cDNA encoding a UDPG gene of roseroot was identified, cloned and characterized. Its ORF (1425 bp) was transferred into E. coli, where the expression of the recombinant enzyme was confirmed. To monitor the enzyme activity, 3 precursors (tyramine, 4-hydroxyphenylpyruvate & tyrosol) of salidroside biosynthesis pathway were added to roseroot callus cultures and samples were harvested after 1, 6, 12, 24, 48 & 96 h. Along with the controls (without precursor feeding), each sample was subjected to HPLC and qRT-PCR for phytochemical and relative UDP-glycosyltransferase gene expression analysis, respectively. The HPLC analysis showed that the salidroside content significantly increased; reaching 0.5% of the callus dry weight (26-fold higher than the control) after 96 h when 2 mM tyrosol was given to the media. The expression of the UDP-glycosyltransferase increased significantly being the highest at 12 h after the feeding. The effect of tyramine and 4-hydroxyphenylpyruvate was not as pronounced as of tyrosol. Here, we introduce a R. rosea specific UDPG gene and its expression pattern after biotransformation of intermediate precursors in in vitro roseroot callus cultures.

Natural deep eutectic solvents (NADES) are a green, promising class of solvents. Phenolic compounds are among the targets of NADES’ use in foods. A health claim is admitted by European Regulations for olive oils (OOs) containing at least 250 mg kg−1 of selected polyphenols (hydroxytyrosol and its derivatives, included tyrosol, HTD), but their determination involves analytical issues that are being currently debated. A NADES based on glucose and lactic acid was here used to develop a green and rapid tool for correct labelling of OOs. 163 OOs were submitted to liquid/liquid extraction with the NADES. Regression and classification approaches were adopted to relate features of the UV spectra of extracts to HTD content. The models allowed to assess HTD content for screening purposes (R2prediction = 0.84, RMSEP = 35.5 mg kg−1). For labelling purposes, oils could be labelled according to health claim limits with an error of 0.6%.

A phenolic-UDP-glycosyltransferase Bs-PUGT from Bacillus subtilis PI18 was cloned and expressed in Escherichia coli BL21 (DE3). The purified Bs-PUGT could catalyze the glycosylation of tyrosol, 4-hydroxybenzyl alcohol, 2-hydroxybenzyl alcohol, caffeic acid, cinnamic alcohol, ferulic acid, and so on. This enzyme showed a high activity and stability over a broad pH range and was sensitive to temperature. Studies on the kinetic parameters indicated that the affinity of Bs-PUGT to UDP-G (Km) and its catalytic efficiency (Kcat) increased by 1.5-fold and 1.7-fold, respectively, with the addition of 10 mM Ca2+. The most effective glycosylation of caffeic acid catalyzed by whole-cell E. coli/Bs-PUGT was achieved with a molar yield of 78.3% in a system with pH 8.0, 30 °C, 25 g/L sucrose, 10 mM Ca2+, and 0.5 g/L substrate concentration. The addition of Ca2+ increased the molar yield of caffeic acid glucosides and shortened the reaction. This work proposes a strategy for the efficient glycosylation of phenolic compounds by microbe-derived glycosyltransferase assisted by metal ions.

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.

There is an increasing trend in the consumption of olive oil, especially extra virgin olive oil, due to its health benefits. These health benefits are mainly correlated to health-promoting components of olive oil such as polyphenols, tocopherols, and carotenoids, positive effects of olive oil on the inhibition of foodborne pathogens, stimulation of the growth of beneficial microorganisms, and its antioxidant activity. These attributes make olive oil one of the leading healthy edible oils worldwide.The current study overviews the recent findings on the health benefits of olive oil consumption including its effects on gut microbiota, its antioxidant activity, and its ability in preventing cardiovascular disease (CVD). In addition, the potential mechanism involved in these health-promoting effects are discussed.Key findings and conclusions: This study showed that olive oils originated from various regions of the world can pose some positive effects on gut microbiota. Moreover, this edible oil (especially the extra virgin type) can prevent CVD due to the high levels of valuable bioactive components including phenolic compounds (e.g. oleocanthal, tyrosol, hydroxytyrosol, oleuropein, and oleuropein aglycone) and the presence of highly bioavailable health-promoting carotenoids such as provitamin A, β-carotene, and lutein. Furthermore, the oral intake of extra virgin olive oil can be beneficial in preventing cancer and type 2 diabetes. Therefore, the consumption of olive oil, especially the extra virgin type, can be recommended not only because of its healthy fatty acid profile (particularly oleic acid) but also due to valuable positive effects of its bioactive components on human health.

Tri cluster is responsible for the biosynthesis of trichothecenes in Trichoderma spp. Tri6 gene present within the cluster encodes for a transcriptional regulator and is vital for the expression of all other tri genes of the cluster. Tri6 encodes for a 218-amino-acid residues long protein which contains three zinc finger motifs. Tri6 is able to regulate and bind within the GTGA/TCAC promoter region of tri genes. Here we highlight the binding of tri6 with the regulatory DNA element present at the upstream of tri3 gene and effect of two quorum-sensing molecules tyrosol and farnesol on its binding. Analysis showed that tyrosol binds at sequence GTGA/TCAC specific for tri6 binding and thus do not allow tri6 to bind on promoter region. Interactions of tyrosol with zinc finger motif of tri6 protein also resulted in structural changes making tri6 unsuitable for binding with the regulatory DNA element of tri3 gene promoter resulting in downregulation of the gene. Structural changes also resulted in loss of zinc from zinc finger 2 motif. In contrast to the tyrosol, tri6-DNA complex could easily accommodate farnesol molecule without showing any interference with the functional conformation of the tri6-DNA complex. Therefore, tri gene expression seems not to be negatively regulated by the farnesol.

View references (28) Hemp seed oil is an extraordinary dietary source of polyunsaturated fatty acids (PUFAs), to huge health benefits are related. PUFAs abundance could indeed contribute the oil turning rancid and deteriorating through oxidation. Thus, antioxidant compounds, characteristic of hemp seed matrix, should be more favorably extract to hopefully safeguard the oil stability. Moreover, antioxidants ability to counteract the onset of oxidative stress-related diseases could be employed to further enhance hemp seed oil functional value. In this context, phenols and polyphenols, which are poorly explored in hempseed oil so far, are thoroughly investigated by untargeted UHPLC-HRMS and MS/MS techniques in seed oils from Cannabis sativa L. cv USO31. Data recorded highlighted that hemp seed oil could contain, as minor constituents, saccharides, phenol compounds (some of them never described before - e.g. tyrosol hexoside, caffeoyl tartaric acid isomers), as well as flavonoids, of which glycosides of flavonols quercetin, kaempferol and isorhamnetin were the most representative. Glucuronide derivatives were also present. Multivariate principal-component analysis (PCA) highlighted that agronomic practices (e.g. plant density/m2, use of fertilizers) and cold-pressing extraction parameters (e.g. temperature, nozzle size) massively affected the relative content of each compounds’ class. Hemp seeds from soils, which did not undergo pre-seeding fertilization, and with 60 plant/m2crop density, ensured the highest production of phenols and polyphenols, whereas their abundance could be compromised when the plant density was halved. © 2019 Elsevier B.V.

Three new sesquiterpenes (1-3) and one new monoterpene (4) were isolated from the soil-derived fungus Trichoderma reesei PSU-SPSF013 along with five known compounds including hydroheptelidic acid (5), 5-hydroxy-3-hydroxymethyl-2-methyl-7-methoxychromone (6), adenosine (7), uridine (8) and tyrosol (9). Their structures were elucidated by spectroscopic analyses. The absolute configuration of the secondary alcohol moiety in 2 was assigned using Mosher’s method whereas that of 1, 3 and 4 was established by comparison of their specific rotations with those of structurally related compounds. Compounds 3-5 displayed interesting antifungal activity against Cryptococcus neoformans ATCC90113 with the respective MIC values of 8, 8 and 4 μg/mL. Moreover, only 3 was active against C. neoformans ATCC90112 with the MIC value of 32 μg/mL. Interestingly, 4 and 5 were noncytotoxic towards noncancerous Vero cells.

Olive oil is widely accepted as a superioredible oil. Great attention has been given lately to olive oil polyphenols which are linked to significant health beneficial effects. Towards a survey of Greek olive oil focusing on polyphenols, representativeextra virgin olive oils(EVOOs) from the main producing areas of the country and the same harvesting period have been collected and analyzed. Significant differences and interesting correlations have been identified connecting certain polyphenols namelyhydroxytyrosol,tyrosol, oleacein and oleocanthal with specific parameters e.g. geographical origin, production procedure and cultivation practice. Selected EVOOs polyphenol extracts, with different oleacein and oleocanthal levels, as well as isolated oleacein and oleocanthal were bio-evaluated in mammalian cells and as a dietary supplement in theDrosophila in vivomodel. We found that oleocanthal and oleacein activated healthy aging-promoting cytoprotective pathways and suppressedoxidative stressin both mammalian cells and in flies.

The role of cations and anions of imidazolium ionic liquid-based microwave-assisted extraction system for salidroside and tyrosol of Rhodiola was investigated. To evaluate eight kinds of imidazolium-based ionic liquid with different cations and anions on molecule level, the geometries of related IL molecules and target extracts were optimized by density functional theory at the B3LYP/6-311++G(d, p) level. Electrostatic potential (ESP) distributions of these molecules above are identified in the water modeled by the polarizable continuum model. The theoretical and experimental analysis shows there is some correlation between the characteristic values of ESP distribution and extraction yield. The more similar the ESP distribution of ILs are to salidroside and tyrosol, the higher the extraction yields are. Wider variability of ESP is beneficial to extraction. The main role of cations is interaction with extract molecules by its positive ESP regions. So the cations influence the solubility of extracts by the molecular interaction. Unlike the cations, the types of anions can affect the structure of the cell wall. The ILs with Br anion have greater ability to dissolve cellulose and break the cell wall, which made the target components within the cell could effectively dissolve. Due to the differing function of cations and anions of ILs, the ionic liquid-based MAE could provide higher extraction yields and take much shorter extraction time than conventional organic solvents.

In this work it is explored a real applicability of miniaturised and portable biosensing technology for the estimation of total phenolic content in 15 different commercial beers by applying direct amperometry. Gold nanoparticles screen-printed electrodes were thoroughly modified with tyrosinase (Tyr-AuNPS-SPCEs), which was immobilised on the surface by crosslinking with glutaraldehyde. All chemical and instrumental variables involved in the electrochemical method were optimised to develop a reliable and powerful tool to estimate rapidly the content of phenolic compounds in complex beer samples. Catechol, phenol, caffeic acid and tyrosol were analysed individually using the proposed methodology and good analytical and kinetic performances were obtained. Total phenolic content in tested beers (high fermented, low fermented and non-alcoholic) were expressed as mg L−1 of tyrosol, which is one of the major phenolic compound reported in beer. Moreover, the developed amperometric methodology was successfully benchmarked against standardised Folin-Ciocalteau spectrophotometric method with a good Pearson correlation (r = 0.821, p

Tyrosol is a pharmacologically active phenolic compound widely used in the medicine and chemical industries. Traditional methods of plant extraction are complicated and chemical synthesis of tyrosol is not commercially viable. In this study, a recombinant Escherichia coli strain was constructed by overexpressing the phenylpyruvate decarboxylase ARO10 from Saccharomyces cerevisiae, which could produce tyrosol from glucose. Furthermore, genes encoding key enzymes from the competing phenylalanine and tyrosine synthesis pathways and the repression protein TyrR were eliminated, and the resulting engineered strain generated 3.57 mmol·L− 1 tyrosol from glucose. More significantly, codon optimization of ARO10 increased expression and tyrosol titer. Using the novel engineered strain expressing codon-optimized AR10 in shake-flask culture, 8.72 mmol·L− 1 tyrosol was obtained after 48 h. Optimization of the induction conditions improved tyrosol production to 9.53 mmol·L− 1 (1316.3 mg·L− 1). A higher titer of tyrosol was achieved by reconstruction of tyrosol synthetic pathway in E. coli.

42 Páginas; 2 Figuras; 3 Tablas; 4 Figuras suplementarias; 4 Tablas suplementarias, Genes with the potential to code for enzymes involved in phenolic compound metabolism were detected in the genome of Lactobacillus pentosus IG1, isolated from a green olive fermentation. Based on homology, these genes could code for a 6-P-β Glucosidase, two different Tannases, a Gallate decarboxylase and a p-Coumaric decarboxylase. Expression of up to seven of these genes was studied in L. pentosus IG1 (olive fermentation) and CECT4023T (corn silage), including responses upon exposure to relevant phenolic compounds and different olive extracts. Genes potentially coding Tannase, Gallate decarboxylase and p-Coumaric acid decarboxylase significatively increased their expression upon exposure to such compounds and extracts, although it was strain dependent. In general, both the genetic organization and the characteristics of gene expression resembled very much those described for Lactobacillus plantarum. In accordance to the observed induced gene expression, metabolism of specific phenolic compounds was achieved by L. pentosus. Thus, methyl gallate, gallic acid and the hydroxycinamic acids p-coumaric, caffeic and ferulic were metabolized. In addition, the amount of phenolics such as tyrosol, oleuropein, rutin and verbascoside included in a minimal culture medium was noticeably reduced, again dependent on the strain considered., This research was funded by the Spanish Ministry of Economy and Competitiveness through the Project AGL2012-33400, and by the Junta de Andalucía Excellence ProjectAGR-07345. All these projects included FEDER funds. JAC was the recipient of a post-doctoral grant awarded by the Junta de Andalucía as part of the Project AGR-07345. HLP was the recipient of a contract funded by the Spanish Ministry of Economy and Competitiveness as part of the ProjectAGL2012-33400, as well as by the CSIC Project no. 201670E028. We want to express our gratitude to the table olive enterprises which have collaborated in this study: Aceitunas Los Dos S.L. (Almensilla), Olive Aljarafe S.L. (Pilas), Aceitunas Francisca Moreno S.L. (Pilas), Goya en España S.A.U. (Alcalá de Guadaira), and Jolca S.A. (Huévar).

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.

Olive tree is one of the most valuable crops cultivated for its oil that is rich in antioxidants. The beneficial effects of oleuropein and hydroxytyrosol (HT), the most abundant and the most powerful antioxidant respectively, as well as tyrosol, HT's precursor molecule, are well studied however their biosynthetic pathways are not yet clarified. The transcriptome analysis of the young olive fruit, cultivar "Koroneiki", revealed transcripts of all the enzymes used to reconstitute the biosynthetic pathway of tyrosol and HT in other organisms. We also identified transcripts of the genes that encode for enzymes involved in the secologanin biosynthesis, oleuropein's precursor molecule. Following the transcriptome analysis, the relative expression of the transcripts was monitored during fruit development and compared to the concentration of the 3 metabolites they synthesize at the same developmental stages. The highest expression levels, accompanied by the maximum concentration of the three metabolites, was found in the young olive fruit. The correlation between the expression profile and the metabolites' concentration indicates that the transcripts were correctly identified and the synthesis of the compounds is regulated at a transcriptional level. Interestingly, HT showed a sudden increment in the final developmental stage of the black mature fruit that is attributed to oleuropein catabolism.

This work compares the ability of physical and chemical treatments, namely adsorption and electrochemical advanced oxidation processes, to remove tyrosol from aqueous medium. Adsorption on graphene nanoplatelets (GNPs) performed much better than a graphite intercalation compound. Adsorption isotherm fit with Freundlich model (R2 = 0.96), which is characteristic of a chemisorption process. Successful electrochemical regeneration enables 5 successive adsorption/regeneration cycles before corrosion of GNPs occurs. Other typical aromatic contaminants that may coexist with tyrosol can be also adsorbed on GNPs. Percentage of regeneration efficiency of GNPs showed a higher affinity towards Lewis acids group compounds and a lower one towards Lewis base. The treatment of 100 mL of 0.723 mM tyrosol solutions in non-chlorinated and chlorinated matrices at pH 3.0 was carried out by electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF). Trials were made with a BDD anode and an air-diffusion cathode at 10-30 mA cm-2. Hydroxyl radicals formed at the anode from water oxidation and/or in the bulk from Fenton's reaction between added Fe2+ and generated H2O2, along with active chlorine produced in chlorinated medium, were the main oxidants. Tyrosol concentration always decayed following a pseudo-first-order kinetics and its mineralization rose as EO-H2O2 < EF < PEF, more rapidly in the chlorinated matrix. The potent photolysis of intermediates under UVA radiation explained the almost total mineralization achieved by PEF in the latter medium. The effect of current density and tyrosol content on the performance of all processes was examined.

Cyclodextrin enhanced pulsed ultrasound assisted extraction procedure was developed for obtaining olive pomace extract rich in bioactive polyphenols, principally oleuropein, tyrosol, and hydroxytyrosol. 20-minute extraction using 12 mm probe at 100% output intensity was selected as optimal for the extraction of olive pomace polyphenols, using 60% ethanol at 1:40 solvent to solid ratio. Addition of cyclodextrins to extraction solvent (especially randomly-methylatedbeta cyclodextrin and hydroxypropyl-beta cyclodextrin) significantly affected extraction yields, stability and the appearance (colour and particle size distribution) of obtained extracts. Extracts obtained under optimized conditions contained 887 mgkg-1 of hydroxytyrosol, 1117 mgkg-1 of tyrosol and 1744 mgkg-1 of oleuropein. In comparison to conventional solvent extraction, application of ultrasound-assisted extraction resulted in significantly higher yields, reduced extraction time and solvent consumption.

Olive (Olea europaea L.) is one of the most important fruit species in the Mediterranean basin, where 95% of the world's olive orchards are planted, and has become an economically valuable crop worldwide due to an increasing demand in olive oil for human consumption. The aim of the present research was to classify Tunisian olive cultivars based on their phenolic profile and to test the potentiality of chemometrics as a tool for cultivars discrimination. The phenolic compounds present in 21 samples of olive leaves, collected during the normal picking period for olive oil production in South Tunisia, were analysed by liquid chromatography mass spectrometry. Models based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used for discrimination purposes as a function of the tree varieties and cultivation zone. Qualitative and quantitative compositional analysis revealed 12 major phenolic compounds among which oleuropein (110.38–4741.62 mg/kg), hydroxytyrosol (5.40–290.19 mg/kg), apigenin 7-O-glucoside (9.44–2475.53 mg/kg), tyrosol (2.10–174.62 mg/kg), catechin (0–37.60 mg/kg) and vanillic acid (3.23–256.57 mg/kg) were identified. Oleuropein showed the highest amount in Fougi cultivar (4741.62 mg/kg), whereas the lowest level was registered in Zarrazi injassi cultivar (110.38 mg/kg). However, Zalmati Zarzis exhibited high concentrations of tyrosol, vanillic and caffeic acid, and vanillin. In general, rutin and luteolin 7-O-glucoside were the two main flavonoids detected. Dendrogram analysis revealed three main clusters, further confirmed through PCA.

NMR spectroscopy in combination with multivariate statistical analysis provides the promising feasibility for discriminating food origins. In this study, this technique was successfully employed to analyze various refined edible oils from seven plant-origins including sunflower seed, rapeseed, sesame, soybean, peanut, corn and olive oils. A variety of fatty acids in edible oils including oleic acid, linoleic acid, linolenic acid, saturated fatty acids and the corresponding iodine values were quantified via a single NMR measurement, and principal component analysis was used to distinguish their plant origins. The compositional differences both in major and minor components were derived from the pair-wise orthogonal partial least squares discriminant analysis models between the other edible oils and olive oil with highest nutritional value and favorable flavor. The results suggested that olive oil and rapeseed oil seem to provide the more nutritional benefit to human, and the minor components such as terpenes and tyrosol also induce health benefits and desirable flavor. The further analysis of different-producing-region sesame oils indicated that the altitude gives the great contribution to their compositional differences, and the climatic conditions also cause the compositional variations.

Synthetic microbial coculture to express heterologous biosynthetic pathway for de novo production of medicinal ingredients is an emerging strategy for metabolic engineering and synthetic biology. Here, taking efficient production of salidroside as an example of glycosides, we design and construct a syntrophic Escherichia coli-E. coli coculture composed of the aglycone (AG) strain and the glycoside (GD) strain, which convergently accommodate biosynthetic pathways of tyrosol and salidroside, respectively. To accomplish this the phenylalanine-deficient AG strain was engineered to utilize xylose preferentially and to overproduce precursor tyrosol, while the tyrosine-deficient GD strain was constructed to consume glucose exclusively and to enhance another precursor UDP-glucose availability for synthesis of salidroside. The AG and GD strains in the synthetic consortium are obligatory cooperators through crossfeeding of tyrosine and phenylalanine and compatible in glucose and xylose mixture. Through balancing the metabolic pathway strength, we show that the syntrophic coculture was robust and stable, and produced 6.03 g/L of salidroside. It was the de novo production of salidroside for the first time in E. coli coculture system, which would be applicable for production of other important glycosides and natural products.

The applicability of using front-face fluorescence spectroscopy to compare profiles of commercially produced New Zealand Pinot Noir grape juice and wine samples from closely related vineyard sites and different grapevine clones was assessed by monitoring eleven batches of grape juices (different sites and clones) during the commercial winemaking process (pre-fermentation, pre-barrelling, barrelled wines). Deconvolution of the recorded fluorescence excitation-emission matrices was carried out using parallel factor analysis (PARAFAC) and the scores plots thereof showed sample groupings on the basis of clone and indicated chemical differences based on vineyard site, winemaking and barrel properties. The four components revealed by the PARAFAC models had their excitation/emission maxima at 278/360 nm, 260/390 nm, 278/315 nm and 320/415 nm, respectively and were tentatively assigned to multiple fluorophore contributions of tryptophan and hydroxyl benzoic acid derivatives (vineyard site discrimination), caffeic acid (clone discrimination), catechin and tyrosol related fluorophores (winemaking based discrimination). The applied methods after further validation have potential to be used as a rapid way to screen grape juices and wines and to provide winemakers with information on the potential quality of their wine.

The olive oil extraction process is of vital importance for the farmers at Mediterranean countries. However, olive oil production is directly associated with the co-production of large quantities of Olive Mill Wastewater (OMW), which are considered as wastes but at the same time can also be considered as byproducts enriched in high added value constituents, such as phenolic compounds. The idea in the present work is firstly to separate and isolate the low molecular size phenolic compounds from other organic compounds, of high molecular size, using a combination of membrane processes (Ultrafiltration, UF, Nanofiltration, NF, Reverse Osmosis, RO). Further exploitation of the RO concentrate with vacuum distillation and freeze drying leads to the recovery of solid mixtures of the phenolic compounds and sugars. The implementation of cooling crystallization as a next treatment process is suggested for the separation of the phenolic compounds from sugars based on their solubility differences as a function of temperature. Further isolation and purification of phenolic compounds, may be achieved using melting crystallization and each compound may be selectively crystallized at its respective freezing point. To test the purification system proposed here, model “synthetic solutions” were used. The model solutions were made up using compounds with different molecular sizes including phenolic compounds. In the present study, recovering and purification of phenolic compounds was examined by experiments in synthetic OMW, where sucrose and tyrosol were served as model compounds for sugars and phenolics respectively.

Changes in phenolic profiles and color parameters can help to differentiate between extra virgin olive oils (EVOOs) with protected designation of origin (PDO). Phenolic profile characterization and CIELAB parameters determination of 9 PDO EVOOs from Spain were developed. Both properties of EVOOs are very relevant to their commercialization and increase the product value. The Serrana de Espadán olive cultivar was characterized for the first time and showed the highest pinoresinol concentrations and clarities in these olive oils, which are important values for the product image. To detect fraudulent instrumental work and implement quality control, principal component analysis (PCA) and linear discriminant analysis (LDA) were performed. EVOO geographical origin and cultivar distributions were achieved with cumulative variances of 93.4% and 92.4%, respectively. A categorization of PDO EVOOs was proposed using the following 7 phenolic compounds: phenolic alcohols (tyrosol and hydroxytyrosol), 3,4-DHPEA-EDA, 3,4-DHPEA-EA, p-HPEA-EDA, pinoresinol and total phenolic compounds.

Salidroside is a bioactive tyrosine-derived phenolic natural product found in medicinal plants under the Rhodiola genus. In addition to their anti-fatigue and anti-anoxia roles in traditional medicine, Rhodiola total extract and salidroside have also displayed medicinal properties as anti-cardiovascular diseases and anti-cancer agents. The resulting surge in global demand of Rhodiola plants and salidroside has driven some species close to extinction. Here, we report the full elucidation of the Rhodiola salidroside biosynthetic pathway utilizing the first comprehensive transcriptomics and metabolomics datasets for Rhodiola rosea. Unlike the previously proposed pathway involving separate decarboxylation and deamination enzymatic steps from tyrosine to the key intermediate 4-hydroxyphenylacetaldehyde (4-HPAA), Rhodiola contains a pyridoxal phosphate-dependent 4-HPAA synthase that directly converts tyrosine to 4-HPAA. We further identified genes encoding the subsequent 4-HPAA reductase and tyrosol:UDP-glucose 8-O-glucosyltransferase, respectively, to complete salidroside biosynthesis in Rhodiola. We show that heterologous production of salidroside can be achieved in the yeast Saccharomyces cerevisiae as well as the plant Nicotiana benthamiana through transgenic expression of Rhodiola salidroside biosynthetic genes. This study provides new tools for engineering sustainable production of salidroside in heterologous hosts.

The phenylpropenoid glycosides rosavin, rosarin, rosin summarised as ‘total rosavins’ are quality indicators of Rhodiola rosea L. Here we report the systematic quantification of these glycosides and the aglycon cinnamyl alcohol in various provenances cultivated homogenously at 1580 m altitude. (I) We examined rhizomes versus roots in cultivation year 9 (20 provenances). Extracts (70% ethanol) contained 0.5–4.3 mg/mL (rhizomes) and 0.4–2.5 mg/mL (roots) total rosavins. The rosavin/cinnamyl alcohol ratio (average rhizomes 8.1:1, roots 6.2:1), was more influenced by plant origin than plant part. We additionally analysed salidroside including its aglycon tyrosol. The rosavins/salidroside ratios (including aglycons) of 6.4:1 (rhizome) and 5.5:1 (root) indicated authentic R. rosea independent of plant part and origin. (II) Rhizomes extracts (8 provenances) from various dates during years 6 and 7 contained 0.4–4.8 mg/mL total rosavins corresponding to 0.2–3.0% in the dry drug. Age (decreasing trend) and provenance impact were superposed by seasonal variation with a phenylpropenoid peak in spring. Rosavin/cinnamyl alcohol ratios in North European plants were 3–8:1, for Alpine/Pyrenean plants 9–14:1. (III) Compared to our previous dataset from cultivation in South England, on average, there was no major difference between phenylpropenoid values from cultivation at 65 m and 1580 m apart from moderately more cinnamyl alcohol at higher altitude. As per provenance, absolute values were site dependent but phenylpropenoid glycoside/aglycon ratios consistent. In conclusion, this is the first systematic investigation for a high altitude cultivation of R. rosea demonstrating the major extent plant part, season and age influence absolute phenylpropenoid values. In contrary, relative phenolic compound profiles are mostly origin-determined, independent of cultivation conditions and site, and could be used for authentication in quality control.

Fungi belonging to the genus Cunninghamella are often used as microbial models of mammalian metabolism owing to their ability to transform a range of xenobiotic compounds. Furthermore, under specific growth conditions species such as Cunninghamella elegans and Cunninghamella echinulata grow as biofilms enabling a convenient semi-continuous production of valuable drug metabolites. However, the molecular mechanism of biofilm regulation is not understood, thus controlling biofilm thickness limits the productive applications of it. In this paper we describe the identification of two molecules, tyrosol and tryptophol, that were identified in C. blakesleeana cultures, but not in C. elegans and C. echinulata. The molecules are known quorum sensing molecules (QSMs) in yeast and their potential role in Cunninghamella biofilm regulation was explored. Both were present in higher concentrations in C. blakesleeana planktonic cultures compared with biofilms; they inhibited the growth of the fungus on agar plates and selectively inhibited biofilm growth in liquid cultures. The molecules had a comparatively minor impact on the biofilm growth of C. elegans and C. echinulata and on the growth of these fungi on agar plates. Finally, when exogenous tyrosol or tryptophol was added to previously grown C. blakesleeana biofilm, detachment was visible and new additional planktonic culture was measured, confirming that these molecules specifically regulate biofilm growth in this fungus.

Palm date seeds oil of eight varieties were investigated for physical, chemical, and phytochemical analysis, and compared to used commercial oils. Significant differences were observed among varieties. The oil content of the eight varieties ranged from 6.05 to 10.25%. Fatty acid analysis using GC-MS revealed that oleic acids were the dominant component (38.67–44.38%) followed by lauric (21.72–26.66%), myristic (11.26–13.04%); palmitic (9.65–11.38%); linoleic (6.25–8.24%); stearic (3.06–3.32%) while linolenic acid was found in traces. The carotenoids content ranged from 17.57 ± 0.02 to 12.35 ± 0.03 mg/kg oil, total phenolic content ranged from 58.04 ± 0.30 to 181.03 ± 0.75 mg GAE/100 g and flavonoids content values ranged from 22.81 ± 0.08 to 53.41 ± 0.72 mg RE/100 g oil. The antioxidant activities (DPPH and ABTS) varied from 17.28 ± 1.06 to 47.37 ± 1.05 and 3.10 ± 0.28 to 8.83 ± 0.08 mg AAE/100 g, respectively. The phenolic compounds identified in seed oils were hydroxytyrosol (30.36 ± 0.21 to 38.63 ± 0.14 μg/g oil), procatechuic acid (14.47 ± 0.09 to 35.21 ± 0.07 μg/g oil), tyrosol (14.36 ± 0.03 to 21.23 ± 0.12 μg/g oil), gallic acid (7.37 ± 0.04 to 17.68 ± 0.09 μg/g oil), caffeic acid (3.21 ± 0.11 to 7.09 ± 0.12 μg/g oil) and oleuropein (1.37 ± 0.02 to 7.27 ± 0.05 μg/g oil). The total amount of the identified phenolic compounds recorded in Bouslikhan variety (107.32 μg/g oil). The results suggest that palm date seeds oil are strong radical scavengers and can be considered a good source of natural antioxidants for medicinal, functional food, and commercial uses.

The ultrasound-assisted enzyme hydrolysis (UAEH) procedure for extraction of phenolics from olive waste (OW) was established. The optimized conditions obtained with response surface methodology (RSM) were pH 5.75, treatment 40 min and temperature 55 °C, the yield obtained reached to 4.0%. The extraction kinetics model was fitted well to the ln ( C t / C 0 ) = kt , and the rate constants ( k ) increased with the increased in the extraction temperature. Moreover, the values of k were higher and the activation energy was lower than ultrasound treatment alone. The thermodynamic parameters indicated the extraction process was easier under the UAEH. Compared with the petroleum ether and n-butyl alcohol, ethyl acetate extract fraction had high phenolic content (64.4 mg/g), especially hydroxytyrosol and tyrosol (17.2 mg/g and 14.1 mg/g), and exhibited excellent antioxidant activities in DPPH·, ABTS + ·and FRAP assay. These finding revealed that OW could be used for a enrich source of natural phenolic compounds for development of food industry. Industrial relevance Olive waste (OW) has been widely paid attention as sources of high-added value compounds, such as phenolic which can be obtained by the several methods. And phenolic extract as a food additive can not only improve the sensory quality of food, but also can enhance antioxidant capacity in fatty food matrices. Moreover, the use of this extract has better economic benefits than synthetic additives usually used in food industry. In this study, a novel green, simple and efficient technology was employed to extract the phenolic compounds, which was suitable for large-scale industrial use. The results indicated that ultrasound-assisted enzyme hydrolysis (UAEH) has significant potential in the extraction process of phenolics from OW exhibiting higher phenolic yield in shorter extraction times.

Maturity is one of the most important factors associated with the quality of olive products, however the molecular events underlying olive drupe development remain poorly characterized. Using proteomic and metabolomic approaches, this study investigated the changes in the olive drupes (cv. Chondrolia Chalkidikis) across six developmental stages (S1-S6) that characterize the dynamics of fruit growth and color. Primary metabolites, including carbohydrates and organic acids (i.e., xylose, malic acid), showed significant accumulation in the black maturation stage. Temporal changes in various secondary metabolites (e.g., oleuropein, oleacin and tyrosol) were also observed. Proteins involved in oxidation-reduction (i.e., LOX1/5), carbohydrate metabolism (i.e., GLUA, PG) and photosynthesis (i.e., chlorophyll a-b binding proteins) significantly altered in the turning black compared to the green mature stage. By providing the first proteometabolomic study of olive drupe development, this investigation offers a novel framework for further studies on this economically relevant crop.

Two series of 3,5-disubstituted isoxazoles (6a–e) and 1,4-disubstituted triazoles (8a–e) derivatives have been synthesized from tyrosol (1), a natural phenolic compound, detected in several natural sources such as olive oil, and well-known by its wide spectrum of biological activities. Copper-catalyzed microwave-assisted 1,3-dipolar cycloaddition reactions between tyrosol-alkyne derivative 2 and two series of aryl nitrile oxides (5a–e) and azides (7a-e) regiospecifically afforded 3,5-disubstituted isoxazoles (6a–e) and 1,4-triazole derivatives (8a–e), respectively in quantitative yields. Synthesized compounds were purified and characterized by spectroscopic means including 1D and 2D NMR techniques and HRMS analysis. The newly prepared hybrid molecules have been evaluated for their anticancer and hemolytic activities. Results showed that most derivatives displayed significant antiproliferative activity against human glioblastoma cancer cells (U87) in a dose-dependent manner. Compounds 6d (IC50 = 15.2 ± 1.0 μg/mL) and 8e (IC50 = 21.0 ± 0.9 μg/mL) exhibited more potent anticancer activity. Moreover, most derivatives displayed low hemolytic activity, even at higher concentrations which suggested that these classes of compounds are suitable candidates for further in vivo investigations. The obtained results allow us to consider the newly synthesized isoxazole- and triazole-linked tyrosol derivatives as promising scaffolds for the development of effective anticancer agents.

The estimation of hydroxytyrosol-tyrosol derivatives amounts in olive oils through the analysis of olive pastes collected during malaxation is of utmost relevance due to the relationship with the oils' health claim regarding the protection of blood lipids from oxidative stress. Olive pastes were collected during the industrial extraction of cv. Cobrançosa oils (060 min; 2234 °C). Total phenolic contents of pastes' extracts were assessed (28005400 mg GAE/kg paste). Oils were laboratory-extracted from each paste and, after acid hydrolysis, the contents of hydroxytyrosol and tyrosol derivatives as their sum were determined (25135, 62120 and 68255 mg/kg oil). Olive paste extracts were analyzed with a lab-made potentiometric electronic tongue. The device enabled estimating the total phenolic contents of the pastes (internal-validation: correlation coefficient 0.86, root mean square error 392 mg GAE/kg). Moreover, the electronic tongue allowed a more satisfactory indirect estimation of the total secoiridoids derivatives amounts of the oils (internal-validation: correlation coefficient 0.91, root mean square error 25 mg/kg), based on the olive pastes' potentiometric profiles, without requiring the oils posteriori invasive/destructive analysis. Thus, the electronic tongue could be foreseen as a potential tool for anticipating the health claim fulfilment during oils industrial extraction., The authors are grateful to the Foundation for Science and Tech nology (FCT, Portugal) for financial support by national funds FCT/ MCTES to CIMO (UIDB/00690/2020), to CEB (UIDB/04469/2020), to REQUIMTE-LAQV (UIDB/50006/2020) and to BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. ´Itala Marx acknowledges the Ph.D. research grant (SFRH/BD/137283/2018) provided by FCT. Nuno Rodrigues thanks the National funding by FCT- Foundation for Science and Tech nology, P.I., through the institutional scientific employment program contract., info:eu-repo/semantics/publishedVersion

Olive oil extracted from four exotic olive cultivars was subjected to subcritical treatment using green and organic solvents. The minor phenolic compounds were identified and quantified by RP–HPLC–DAD. Significant (p ≤ 0.05) variation in the phenolic compounds and antioxidant properties was observed with respect to cultivar, solvent and the extraction conditions. For the methanolic and ethanolic extracts, the antioxidant properties generally increased upon subcritical treatment but decreased drastically for subcritical water extraction. Besides correlation among hydroxytyrosol, tyrosol and oleuropein, the multivariate analysis revealed high correlation of antioxidant properties with hydroxytyrosol, oleuropein, tyrosol and apigenin. The principal components analysis (PCA) revealed two components explaining 86.6% variability. PCA separated aqueous and organic solvents both at ambient and subcritical conditions in the score plot. The loading plot exhibited maximum positive loadings of the analyses. It is concluded that subcritical water extraction could be manipulated for the recovery of oleuropein and hydroxytyrosol from olive oil.

The electrochemical oxidation of tyrosol (TY) in aqueous solutions has been studied in order to convert it into hydroxytyrosol (HTY) which is well known for its potentially high added value. This reaction was performed by the electro-Fenton (EF) process using a carbon fiber cloth as cathode and Pt anode. The evolution of the concentrations of TY and its oxidation products HTY and hyroquinone (HQ) during electrolysis, was monitored by means of high performance liquid chromatography (HPLC). The experimental data indicated that the rate of TY disappearance follows a pseudo first order kinetic. The HTY maximum concentration obtained during electrolysis increases with the initial TY concentration. While, it decreases when the applied current increases. The preponderance of HTY with respect to HQ was explained by its stabilization by complexation with iron ions. Finally, a mechanistic pathway for the TY oxidation by the EF process was proposed.

Dyslipidemia, oxidative stress and inflammation are major risky factors involved in the pathophysiology of type 2 diabetes mellitus and atherosclerosis. Multifunctional intervene is more meaningful. The aim of this study was to evaluate the multifunctional effects of two new compounds, combination of fenofibric acid (FA) with tyrosol (T) or hydroxytyrosol (HT). Compared with fenofibrate (FF), FF-HT exhibited excellent antioxidant capacities in vitro and much improved hypolipidemia, reducing plasma triglyceride (TG), total cholesterol (TC), and malonaldehyde (MDA) by 76%, 54%, and 28%, while FF-T decreased the plasma parameters by 16%, 10%, and 20% in hyperlipidemic mice induced by Triton WR 1339. Furthermore, compound FF-HT exhibited significant antihyperglycemic, antihyperlipidemic, antioxidant and anti-inflammatory activities as well as attenuating hepatotoxicity in a type 2 diabetes experimental mouse model. The histological findings showed that FF-HT suppressed the development of hepatic lipid accumulation and ameliorated the damage in hepatic and pancreatic tissues compared to model mice. This study indicates for the first time that reasonable optimized drug design produce a compound entity which is conducive to the prevention of type 2 diabetes mellitus and its complications.

The aim of the present study is to highlight volatile and targeted non-volatile bioactive compounds in Nuragus wines, as a part of Italian DOC (Controlled Origin Designation) white wines. So far there has not been any systematic study of the chemical compositions and antioxidant activity of this monovarietal wine. Phenolic compounds, volatiles and organic acids were analysed and antioxidant capacity was assessed by spectrophotometric assays. Chromaticity coordinates and technological parameters (alcohol, reducing sugars, pH, total and volatile acidity) were also evaluated. Gallic acid (128 ± 87 mg/L), trans-caftaric acid (81 ± 27 mg/L) and tyrosol (25 ± 8 mg/L) were the most abundant phenolic compounds. The major headspace volatiles were isoamyl alcohol (35.8–76.6%) and 2-phenylethanol (5.9–24.9%). In the wine extracts, the most abundant were 2-phenylethanol (12.3–40.0%), 4- hydroxy-2-phenylethanol (12.5–33.3%), diethyl succinate (5.8–30.3%), (Z)-octadec-9-en-1-ol (5.9– 18.3%) and tryptophol (2.8–15.6%). Nuragus wines exhibited an excellent antioxidant capacity. The data obtained may help Nuragus wine producers to promote this monovarietal wine as a valid complement associated with the Mediterranean diet.

The phenolic profiles of extra virgin olive oils (EVOOs) may influence their cardiovascular benefits. In a randomized crossover of acute EVOO intake on platelet function, participants (n = 9) consumed 40 mL of EVOO weekly. EVOOs were matched for total phenolic content and were either tyrosol-poor with 1:2 oleacein/oleocanthal (D2i0.5), or 2:1 oleacein/oleocanthal (D2i2), or predominantly tyrosol (D2i0). Ibuprofen provided a platelet inhibition control. Blood was collected pre- and 2 h post-EVOO intake. D2i0.5 and D2i2 reduced 1 µg/mL collagen-stimulated maximum platelet aggregation (Pmax), with effects best correlated to oleocanthal intake (R = 0.56, P = 0.002). Total phenolic intake was independently correlated to eicosanoid production inhibition, suggesting that cyclooxygenase blockade was not responsible for the Pmax inhibition. Five participants exhibited >25% ΔPmax declines with D2i0.5 and D2i2 intake and plasma metabolomic profiles discriminated subjects by oil responsivity. Platelet responses to acute EVOO intake are associated with oil phenolic composition and may be influenced by diet.

Three new phenylethanoid glycosides, 2-(3-hydroxy-4-methoxyphenyl)ethyl 1- O -β- d -allopyranoside (hodgsonialloside A, 1 ), 2-(3-hydroxy-4-methoxyphenyl)ethyl 1- O -β- d -glucopyranosyl-(1 → 4)-β- d -allopyranoside (hodgsonialloside B, 2 ) and 2-(3-methoxy-4-hydroxyphenyl)ethyl 1- O -β- d -allopyranoside (hodgsonialloside C, 3 ) were isolated from the leaves of Magnolia hodgsonii in addition to six known compounds, tyrosol 4- O -β- d -xylopyranosyl-(1 → 6)-β- d -glucopyranoside ( 4 ), kaempferol 3- O -neohesperidoside ( 5 ), kaempferol 3- O -rutinoside ( 6 ), kaempferol 3- O -α- l -rhamnopyranosyl-(1 → 2)-[α- l -rhamnopyranosyl-(1 → 6)]-β- d -glucopyranoside ( 7 ), (+)-syringaresinol O -β- d -glucopyranoside ( 8 ), and oblongionoside C ( 9 ). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments.