Three compounds were isolated from the water-soluble part of alcohol extracts of rhizomes of Rhodiola kirilowii. Two of them were identified as salidroside and tyrosol, respectively by chemical and spectral analysis. beta-sitosterol was obtained from the petroleum extracts of the plant.

Aromatic constituents from rhizomes of Sophora tonkinensis were purified by extensive chromatographic techniques including column chromatography over macroporous resin,MCI,silica gel,weak acid cation exchange resin,Sephadex LH-20,ODS,and semi-preparative HPLC. Twelve aromatic compounds were isolated and identified from the water aqueous extract of the rhizomes of S.tonkinensis. Their structures were elucidated as 4-( 3-hydroxypropyl) phenol( 1),( ±)-4-( 2-hydroxypropyl) phenol( 2),benzamide( 3),( ±)-3-( p-methoxyphenyl)-1,2-propanediol( 4),4-methoxybenzamide( 5),3-hydroxy-1-( 4-hydroxy-3-methoxyphenyl) propan-1-one( 6),tyrosol( 7),( ±)-2,3-dihydroxypropyl benzoate( 8),vanillin alcohol( 9),7,3'-dihydroxy-8,4'-dimethoxyisoflavone( 10),7,4'-dihydroxy-3'-methoxyisoflavone( 11),and 7,3'-dihydroxy-5'-methoxyisoflavone( 12). Compounds 1-9 were firstly isolated from the Sophora genus. Compounds 4,5,10 and 11 can remarkably protect Hep G2 cell against APAP-induced damage at the concentration of 10 μmol·L-1. Compounds 1-12 exhibited no significant activities on the assays of inhibition of LPS-induced NO production in RAW cell lines and NF-κB inhibition.

According to the previous results from transcriptome analysis of Ligustrum quihoui, a glycosyltransferase gene(xynzUGT) was cloned by rapid amplification of cDNA ends(RACE). The full length cDNA of xynzUGT was 1 598 bp, consisting of 66 bp 5'-UTR, 1 440 bp ORF and 92 bp 3'-UTR. The ORF encoded a 480 amino-acid protein(xynzUGT) with a molecular weight of 54 826.67 Da and isoelectric point of 5.82. The structure of enzyme was analyzed by using bioinformatics method, the results showed that the primary structure contained a highly conserved PSPG box of glycosyltransferase, the secondary structure included α helix(38%), β sheet(12.1%) and random coil(49.9%), and tertiary structure was constructed by peptide chain folding to form two face-to-face α/β/α domains(often referred to as a Rossmann domains), between which a substrate binding pocket is sandwiched. The phylogenetic tree analysis indicated that xynzUGT might catalyze glycosylation of phenylpropanoids, such as tyrosol. Further simulation experiment of molecular docking between enzyme and tyrosol showed that Gly138 and Ser285 located in the binding pocket interacted with tyrosol by hydrogen bonding. SDS-PAGE analysis exhibited that the prokaryotic expression system successfully expressed recombinant xynzUGT with molecular weight of 58 370.57 Da, but it exists in the form of non-soluble inclusion bodies. Using the molecular chaperone and enzyme co-expression method, the soluble expression was promoted to some extent. The above works laid the foundation for further studying on enzymatic reaction in vitro and clarifying the functional mechanism of enzyme.

Two new hydronaphthoquinones, aggregatins E and F (1 and 2, resp.) were isolated from the tubers of Sinningia aggregata (Ker-Gawl.) Wiehler (Gesneriaceae), along with twelve known compounds aggregatin D (3), tectoquinone (4), 1-hydroxy-2-methylanthraquinone (5), icosyl ferulate (6), pustuline (7), 1,6-dihydroxy-2-methylanthranquinone (8), 6-hydroxy-2-methylanthraquinone (9), 7-hydroxy-2-methylanthraquinone (10), tyrosol (11), halleridone (12), calceolarioside B (13), and cornoside (14). All compounds were identified by analysis of spectroscopic and spectrometric data. Compounds 3, 4, and 10 had already been reported in this species. Compounds 2 and 3 were evaluated against several tumor cell lines, but only 3 exhibited activities against UACC-62, 786-0 and OVCAR-3 cell lines, with IC50 values of 12.3, 12.8 and 0.3 μg/ml, respectively, without toxic effects on non-cancer cell line HaCat (human keratinocyte).

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 that with a graphite intercalation compound. Adsorption isotherms were found to follow the 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.

Ethnopharmacological relevance: Duoxuekang (DXK, ཁྲག་འཕེལ་བདེ་བྱེད།) is a clinical experience prescription of CuoRu-Cailang, a famous Tibetan medicine master, which has effective advantages in the treatment of hypobaric hypoxia (HH)-induced brain injury. However, its underlying mechanisms remain unclear.

Aim of the study: The present study was designed to investigate the effects of DXK on cerebrovascular function of HH-induced brain injury in mice.

Materials and methods: DSC-MR imaging was used to evaluate the effect of DXK on the brain blood perfusion of patients with hypoxic brain injury. HPLC analysis was used to detect the content of salidroside, gallic acid, tyrosol, corilagin, ellagic acid, isorhamnetin, quercetin and gingerol in DXK. The model of HH-induced brain injury in mice was established by an animal hypobaric and hypoxic chamber. The BABL/c mice were randomly divided into six groups: control group, model group, Hongjingtian oral liquid group (HOL, 3.3 ml/kg) and DXK groups (0.9, 1.8 and 3.6 g/kg). All mice (except the control group) were intragastrically administrated for a continuous 7 days and put into the animal hypobaric and hypoxic chamber after the last intragastric administration. Hematoxylin-eosin staining was employed to evaluate the pathological changes of brain tissue. Masson and Weigert stainings were used to detect the content of collagen fibers and elastic fibers of brain, respectively. Routine blood test and biochemical kits were used to analyze hematological parameters and oxidative stress indices. Immunofluorescence staining was applied to detect the protein levels of VEGF, CD31/vWF and α-SMA.

Results: The results of DSC-MR imaging confirmed that DXK can increased CBV in the left temporal lobe while decreased MTT in the right frontal lobe, right temporal lobe and right occipital lobe of the brain. DXK contains salidroside, gallic acid, tyrosol, corilagin, ellagic acid, isorhamnetin, quercetin and gingerol. Compared with the model group, DXK can ameliorate the atrophy and deformation, and increase the number of pyramidal neurons in hippocampal CA3 area and cortical neurocytes. Masson and Weigert stainings results revealed that DXK can significantly increase the content of collagen fibers and elastic fibers in brain. Routine blood test results demonstrated that DXK can dramatically decrease the levels of WBC, MCH and MCHC, while increase RBC, HGB, HCT, MCV and PLT in the blood samples. Biochemical results revealed that DXK can markedly increase SOD, CAT and GSH activities, while decrease MDA activity. Immunofluorescence revealed that DXK can notably increase the protein levels of VEGF, CD31/vWF and α-SMA.

Conclusions: In conclusion, this study proved that DXK can ameliorate HH-induced brain injury by improving brain blood perfusion, increasing the number of collagen and elastic fibers and inhibiting oxidative stress injury. The underlying mechanisms may be involved in maintaining the integrity of cerebrovascular endothelial cells and vascular function. However, further in vivo and in vitro investigations are still needed to elucidate the mechanisms of DXK on regulating cerebral blood vessels.

Keywords: Duoxuekang; Tibetan medicine; brain injury; cerebrovascular function; hypobaric hypoxia.

A daily 8-day course of Rhodiolae fluidum extract (1 ml/kg; ED50 = 0.43 ml/kg)--a preparation from the group of adaptogens caused a marked preventive antiarrhythmic effect on models of adrenaline and CaCl2-induced, but not acontine, arrhythmias. Aglycone--n-tyrosol demonstrated a lower antiarrhythmic activity (ED50 = 16 mg/kg) than that of Rhodiola extract.

A total methanolic extract and its sub-extracts of <i>Orobanche crenata</i> (Forssk.) aerial parts were subjected to acute toxicity, anti-inflammatory, and hepatoprotective investigations. The methanolic extract was safe upto 3 g/kg on mice. The EtOAc fraction reduced the carrageenan-induced rat paw edema better than indomethacin. It also demonstrated a drop in the elevated ALT, AST, and TB at 300 mg/kg, better than silymarin. Histopathological examination of liver cells of rats given the EtOAc fraction showed a complete absence of the CCl₄-induced cloudy swelling. A phytochemical investigation of the <i>n</i>-hexane and EtOAc fractions yielded 11 compounds [indole-3-carboxylic acid (<b>1</b>), <i>n</i>-butyl palmitate (<b>2</b>), <em>tyrosol</em> (<b>3</b>), L-rhamnonic acid-1,4-lactone (<b>4</b>), <i>β</i>-sitosterol/stigmasterol mixture (<b>5/5'</b>), <i>β</i>-sitosterol/stigmasterol glycosides mixture (<b>6/6</b>'), chrysoeriol (<b>7</b>), luteolin (<b>8</b>), apigenin (<b>9</b>), crenatoside (<b>10</b>), and verbascoside (<b>11</b>)] as identified by UV, 1D & 2D NMR and ESIMS techniques. Their reported biological actions were in relation to and supported our herein detected pharmacological findings.

Keywords: Orobanche crenata; anti-inflammatory; hepatoprotective; phenylpropanoids; LD50; Orobanchaceae; sterols.

The root bark of Annona cuneata Oliv. is traditionally used in the Democratic Republic of Congo to treat several debilitating conditions, such as hernia, female sterility, sexual asthenia, and parasitic infections. However, little is known about the composition of the secondary plant substances, which may contribute to these traditional medicinal effects. We conducted an ethnobotanical study and then evaluated the composition of the secondary plant substances in extracts of the root bark by using spectroscopic methods. After delipidation, the root bark was lixiviated in methanol, and components in the extract were studied by gas chromatography-mass spectometry, high-performance liquid chromatography (HPLC)-electrospray ionization-MS and nano-electrospray ionization-MS-MS. These methods identified 13 secondary plant substances (almost exclusively phenolic compounds): p-hydroxybenzaldehyde (I), vanillin (II), tyrosol (III), 3,4-dihydroxybenzaldehyde (IV), p-hydroxybenzoic acid (V), vanillyl alcohol (VI), syringaldehyde (VII), 4-hydroxy-3-methoxyphenylethanol (VIII), vanillic acid (IX), 3,4-dihydroxybenzoic acid (X), syringic acid (XI), and ferulic acid (XII), along with the phytosterol squalene (XIII). In the HPLC-based hypoxanthine/xanthine oxidase antioxidant assay system, the methanolic extract exhibited potent antioxidant capacity, with a 50% inhibitory concentration of 72 μL, equivalent to 1.38 mg/mL of raw extract. Thus, a methanol extract of A. cuneata Oliv. contained a range of polyphenolic compounds, which may be partly responsible for its known traditional medicinal effects. More detailed studies on the phytochemistry of this important plant species are therefore warranted.

By using a nontargeted GC-MS approach, 153 individual volatile compounds were found in extracts from untoasted, light toasted and medium-toasted cherry, chestnut, false acacia, as well as European and American ash wood, used in cooperage for aging wines, spirits and other beverages. In all wood types, the toasting provoked a progressive increase in carbohydrate derivatives, lactones and lignin constituents, along with a variety of other components, thus increasing the quantitative differences among species with the toasting intensity. The qualitative differences in the volatile profiles allow for identifying woods from cherry (being p-anisylalcohol, p-anisylaldehyde, p-anisylacetone, methyl benzoate and benzyl salicylate detected only in this wood), chestnut (cis and trans whisky lactone) and false acacia (resorcinol, 3,4-dimethoxyphenol, 2,4-dihydroxy benzaldehyde, 2,4-dihydroxyacetophenone, 2,4-dihydroxypropiophenone and 2,4-dihydroxy-3-methoxyacetophenone), but not those from ash, because of the fact that all compounds present in this wood are detected in at least one other. However, the quantitative differences can be clearly used to identify toasted ash wood, with tyrosol being most prominent, but 2-furanmethanol, 3- and 4-ethylcyclotene, α-methylcrotonolactone, solerone, catechol, 3-methylcatechol and 3-hydroxybenzaldehyde as well. Regarding oak wood, its qualitative volatile profile could be enough to distinguish it from cherry and acacia woods, and the quantitative differences from chestnut (vanillyl ethyl ether, isoacetovanillone, butirovanillone, 1-(5-methyl-2-furyl)-2-propanone and 4-hydroxy-5,6-dihydro-(2H)-pyran-2-one) and ash toasted woods.

The genus Nodulisporium, is known to produce secondary metabolites with structural diversity. A new alkaloid, 2-hy- droxy-1,1-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-one(1), was isolated from the extract of a fungal strain Nodulisporium sp. fermented with rice, together with three known phenols, tyrosol(2), hydroxytyrosol(3), and hydroxytyrosol acetate(4). Their structures were identified by detailed spectroscopic analyses.

The tea-like beverage <i>Stevia rebaudiana</i> Bertoni (<i>Stevia</i>) is popular in China because it reduces blood glucose and has a sweet taste. In this work, a comprehensive quality assessment of <i>Stevia</i> led to the discovery of five phenylethanoid glycosides, namely steviophethanoside (<b>1</b>), cuchiloside (<b>2</b>), salidroside (<b>3</b>), icariside D (<b>4</b>), and <em>tyrosol</em> (<b>5</b>). Of them, compound <b>1</b> is a novel compound. Mass spectrometry and NMR spectroscopy were employed to confirm the absolute configuration. A hydrolytic step with 4 N TFA at 95 °C for 4 h was used to confirm the monosaccharides. In addition, Discovery Studio 4.0 was used to predict the ADME and toxicity activity of compound <b>1</b>. The results suggested that compound <b>1</b> was biocompatible and had poor toxicity, which was verified by rat INS-1 islet β cells through an MTT assay. Meanwhile, a significant stimulatory effect on INS-1 cells was observed, which indicated a hypoglycemic effect of compound <b>1</b>. This is the first report that describes a natural, novel, and hypoglycemic phenylethanoid glycoside in <i>Stevia</i>.

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.

Keywords: BOD(5)/COD ratio; Calcined CaFe–LDH; Layered double oxides; Polyphenols mineralization; Spinel oxide nanoparticles.

Olive tree (Olea europaea L.) leaf, a waste by-product of the olive oil industry, is an inexpensive and abundant source of biophenols of great interest for various industrial applications in the food supplement, cosmetic, and pharmaceutical industries. In this work, the aqueous extraction of high-added value compounds from olive leaves by using microfiltered (MF), ultrapure (U), and osmosis-treated (O) water was investigated. The extraction of target compounds, including oleuropein (Olp), hydroxytyrosol (HyTyr), tyrosol (Tyr), verbascoside (Ver), lutein (Lut), and rutin (Rut), was significantly affected by the characteristics of the water used. Indeed, according to the results of liquid chromatography tandem mass spectrometry, the extracting power of microfiltered water towards rutin resulted very poor, while a moderate extraction was observed for oleuropein, verbascoside, and lutein. On the other hand, high concentrations of hydroxytyrosol were detected in the aqueous extracts produced with microfiltered water. The extraction power of ultrapure and osmosis-treated water proved to be very similar for the bio-active compounds oleuropein, verbascoside, lutein, and rutin. The results clearly provide evidence of the possibility of devising new eco-friendly strategies based on the use of green solvents which can be applied to recover bioactive compounds from olive leaves.

Enzymatic fructosylation of organic acceptors other than saccharides brings new possibilities to synthesize molecules that do not exist in nature. The introduction of fructosyl moiety may lead to glycosides possessing enhanced physicochemical and bioactive properties which could be useful in the pharmaceutical and cosmetic industry. In this work, the regioselective synthesis of tyrosol β-d-fructofuranoside (TF) catalyzed by β-fructofuranosidase is investigated. In the first step, 32 commercial enzyme preparations are screened for fructoside-hydrolyzing activity. The most active preparations are subsequently examined for fructofuranosyl transfer from sucrose to tyrosol. The best candidate, Novozym 188, is chosen to study the effect of reaction conditions on the product formation in a batch reactor. The effects of substrate concentration, temperature, pH, time, and enzyme dosage on the concentration of TF produced are studied using the design of experiments methodology. The maximal product concentration of 3.8 g L^-1 is achieved for the sucrose concentration of 1.5 m, tyrosol concentration of 29 g L^-1 , temperature of 41 °C, and pH 5.1. Besides the main transfructosylation reaction between sucrose and tyrosol, several side reactions take place. A reaction network includes also the formation of fructooligosaccharides and the hydrolysis of sucrose and all reaction products.

Alperujo-a two-phase olive mill waste that is composed of olive vegetation water and solid skin, pulp, and seed fragments - is a highly valuable olive by-product due to its high content in phenolic compounds. In this study, we assessed whether β-cyclodextrin (β-CD), which is used to extract and protect alpejuro phenolic compounds (hydroxytyrosol-O-glucoside, tyrosol, caffeic, and p-coumaric acids) could impact on their bioaccessibility (i.e., the percentage of molecule found in the aqueous phase of the digesta) and uptake by intestinal cells, by using an in vitro digestion model and Caco-2 TC7 cells in culture, respectively. Our results showed that β-CD did not change the bioaccessibility of the selected phenols. Hydroxytyrosol-O-glucoside and caffeic did not cross Caco-2 cell monolayers. Conversely ferulic acid, identified as the main caffeic acid intestinal metabolite, was absorbed through intestinal cell monolayers (~20%). Interestingly, β-CD moderately but significantly improved the local absorption of tyrosol and p-coumaric acid (2.3 + 1.4% and 8.5 ± 4.2%, respectively, p < 0.05), even if their final bioavailability (expressed as bioaccessibility × absorption by Caco-2 cells) was not modified (16.2 ± 0.6% vs. 16.8 ± 0.5% for tyrosol and 32.0 ± 3.2% vs. 37.2 ± 3.2% for p-coumaric acid, from pure alperujo and alperujo complexed with β-CD, respectively). Overall, our results show that β-CD is an interesting extraction and storage agent for phenolic compounds that does not alter their in vitro bioavailability.

Olive mill wastewater has significant polluting properties due to its high phenolic content [mainly tyrosol (trs) and hydroxytyrosol (htrs)]. Growth kinetics and a series of fluorescence induction measurements for Scenedesmus obliquus cultures showed that microalgae can be tolerant of these phenolic compounds. Changes in the cellular energy reserves and concentration of the phenolic compounds adjust the "toxicity" of these compounds to the microalgae and are, therefore, the main parameters that affect biodegradation. Autotrophic growth conditions of microalgae and high concentrations of trs or htrs induce higher biodegradation compared with mixotrophic conditions and lower phenolic concentrations. When microalgae face trs and htrs simultaneously, biodegradation begins from htrs, the more energetically demanding compound. All these lead to the conviction that microalgae have a "rational" management of cellular energy balance. Low toxicity levels lead to higher growth and lower biodegradation, whereas higher toxicity levels lead to lower growth and higher biodegradation. The selection of appropriate conditions (compatible to the bioenergetic strategies of microalgae) seems to be the key for a successful biodegradation of a series of toxic compounds, thus paving the way for future biotechnological applications for solving complicated pollution problems, like the detoxification of olive mill wastewater.

Olive mill wastewater (OMW) is characterized by its high organic load and the presence of phenolic compounds. For first time, a solar distillator was used to investigate the simultaneous solar drying of OMW and the recovery of phenolic compounds with antioxidant properties in the distillate. Two experiments were conducted and the role of thermal insulation on the performance of the distiller was studied. The use of insulation resulted to higher temperatures in the distillator (up to 84.3 °C and 78.5 °C at the air and sludge, respectively), shorter period for OMW dewatering (14 days), while it increased the performance of distillator by 26.1%. Chemical characterization of the distillate showed that pH and COD concentration gradually decreased during the experiments, whereas an opposite trend was noticed for conductivity and total phenols concentration. Almost 4% of the total phenols found initially in OMW were transferred to the distillate when an insulated solar distillator was used. Gas chromatographic analysis of collected distillates confirmed the presence of tyrosol in all samples; whereas hydroxytyrosol was found only in fresh collected distillate samples. Further experiments should be conducted to optimize the process and quantify the concentrations of recovered phenolic compounds.

Stoned green table olives "alcaparras" prepared from five different cultivars (Cv. Cobrançosa, Madural, Negrinha de Freixo, Santulhana and Verdeal Transmontana) were investigated concerning their phenolic composition and antioxidant potential. From each cultivar, five independent lots were prepared. The phenolic profile was determined by HPLC/DAD at 280 nm, and antioxidant potential measured using the reducing power and scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals assays. Twelve phenolic compounds were identified, being hyrdoxytyrosol the most abundant one, followed by verbascoside and tyrosol. Cv. Cobrançosa and Santulhana reported higher content of phenolic compounds, with 165.76 and 163.66 mg/kg of fresh "alcaparras" table olives, respectively. Regarding antioxidant activity, Cv. Santulhana and Cobrançosa showed higher EC(50) values, lower than 1.40 and 0.48 mg/mL for reducing power and DPPH methods, respectively. Significant negative correlations were obtained between olive phenolics and EC(50) values from the antioxidant activity. The direct contact of the pulp with water, characteristic of this processing method, eliminates important hydrossoluble compounds, being the cultivar used an important determinant for the final "alcaparras" composition in terms of ingested phenolic compounds and antioxidant activity.

The production of olive oil generates massive quantities of by-product called olive mill wastewater (OMWW). The uncontrolled disposal of OMWW poses serious environmental problems. The OMWW effluent is rich in several polyphenolic compounds. Liquid-liquid extraction of OMWW using ethyl acetate solvent was used to enrich phenolic compounds under investigation. Total phenolic and flavonoid content and antioxidant activity of the extract were determined. HPLC coupled to photodiode array (PDA) detector was used to analyze the main three phenolic compounds of OMWW, namely, hydroxytyrosol, tyrosol, and oleuropein. The antimicrobial activity of the extract was also investigated. Additionally, the OMWW extract was used as natural preservative and antioxidants for olive oil. Results showed that OMWW is very rich in phenolic compounds and has strong antioxidant activity. HPLC analysis showed that the extract contains mainly hydroxytyrosol and tyrosol but no oleuropein. The OMWW extract showed also positive activities as antibacterial (gram positive and gram negative) and antifungal as well as activities against yeast. The addition of OMWW extract to olive oil samples has an effect on the stability of olive oil as reflected by its acid value, peroxide value, K232 and K270, and total phenolic content.

Bactrocera oleae, an olive fruit fly, is a major olive pest in Algeria. In this study, olives of two Algerian cultivars (Limli and Rougette de Métidja) with different degrees of infestation by the Bactrocera oleae fly (0%, not attacked; 100%, all attacked; and real %) were analysed. The influence of this pest on individual phenolic compounds (HPLC-DAD-FLD) and antioxidant profiles was ascertained. The antibacterial activity against 8 human enteropathogenic bacteria was also assessed. The results show that Rougette de Métidja, the cultivar with higher drupe size, was attacked to a greater degree than Limli, and the B. oleae attack caused a significant decrease in the total phenolic contents (>50%), including oleuropein, verbascoside, luteolin-7-O-glucoside, tyrosol and hydroxytyrosol. The antioxidant and antibacterial activities were highly correlated with the phenolic levels. Extracts from healthy olives were more effective against bacteria than those obtained from attacked olives. Globally, olive fly affected significantly the phenolic compounds of olives and their biological properties.

Three procedures have been investigated for the isolation of tyrosol (1) and hydroxytyrosol (2) from a phenolic extract obtained from the solid residue of olive milling. These three methods, which facilitated the recovery of these phenols, were chemical or enzymatic acetylation, benzylation, and carbomethoxylation, and subsequent carbonylation or acetonation reactions. Several new lipophilic alkyl-carbonate derivatives of hydroxytyrosol have been synthesized, coupling the primary hydroxy group of this phenol, through a carbonate linker, using alcohols with different chain lengths. The antioxidant properties of these lipophilic derivatives have been evaluated by different methods and compared with free hydroxytyrosol (2) and also with the well-known antioxidants BHT and α-tocopherol. Three methods were used for the determination of this antioxidant activity: FRAP and ABTS assays, to test the antioxidant power in hydrophilic media, and the Rancimat test, to evaluate the antioxidant capacity in a lipophilic matrix. These new alkyl-carbonate derivatives of hydroxytyrosol enhanced the antioxidant activity of this natural phenol, with their antioxidant properties also being higher than those of the commercial antioxidants BHT and α-tocopherol. There was no clear influence of the side-chain length on the antioxidant properties of the alkyl-carbonate derivatives of 2, although the best results were achieved mainly by the compounds with a longer chain on the primary hydroxy group of this natural phenolic substance.

Virgin olive oil (VOO) is a functional food specific to the Mediterranean diet and related to human health, especially as a protector of cardiovascular health, in the prevention of several types of cancers, and in modification of immune and inflammatory response. Phenolic compounds have central importance for these extraordinary health benefits. In the production of high-quality olive oils, it is very important to process freshly picked olives and avoid any storage of fruits. However, in Croatia there is a very traditional and environmentally friendly method of olive oil production, where olive fruits are stored in seawater for some time prior to processing. This practice is also notable nowadays since there are people who prefer the characteristic flavor of the "seawater olive oil", although some people argue against its quality and biomedical relevance. In this study, the phenolic contents of VOO prepared from the immediately processed fresh olives and olives processed after storage in seawater were compared with the use of high-performance liquid chromatography-mass spectrometry (HPLC-MS) and spectrophotometric analysis. The results suggest that "seawater olive oil" should be considered as a safe food of biomedical relevance, as it still contains a significant proportion of important phenolics like hydroxytyrosol, tyrosol and oleacein (e.g., 63.2% of total phenols in comparison to VOO).

Keywords: HPLC analysis; olive oil; phenolic compounds; seawater.

This study investigated drum-drying's ability to produce dried food-grade olive pomace as a potential food ingredient that is more nutritionally dense than its freeze-dried and hot-air dried counterparts. The pits and skin were removed from fresh olive pomace, and the remaining pulp was dried to <5% moisture through freeze-drying, hot-air drying, and drum-drying at two rotational speeds. The drying treatments had no significant (P ≤ 0.05) effect on the olive pomace's fat or dietary fiber contents but did increase the L^* , a^* , and b^* color parameter values. Although all the drying treatments significantly (P ≤ 0.05) decreased the fresh olive pomace's antioxidant capacity, drum-drying preserved the olive pomace's antioxidant capacity significantly (P ≤ 0.05) better than freeze-drying and hot-air drying. The drum-dried samples had concentrations of caffeic acid and verbascoside that were significantly (P ≤ 0.05) higher than the other dried pomace samples and were not significantly (P ≤ 0.05) different from the fresh pomace. The drum-dried olive pomace contained concentrations of hydroxytyrosol, tyrosol, vanillic acid, luteolin-7-glucoside, and rutin that were not significantly (P ≤ 0.05) different from the dried sample with the highest concentration of each respective phenolic compound. No oleuropein was found in the fresh or dried olive pomace. The results of this study show that drum-drying is an energy efficient method for converting olive pomace into a stable food-grade supplement that preserves its high phenolic, antioxidant, and dietary fiber contents to potentially benefit human health when incorporated into food or supplement products. PRACTICAL APPLICATION: Pitting and drying converts the olive pomace into a stable form that is free of physical hazards and could be incorporated into food products to increase their nutritional quality through olive pomaces' high fiber, antioxidant, and phenolic contents. Drum-drying allows food-grade olive pomace to retain higher amounts of beneficial soluble phenolics and a higher antioxidant capacity than conventional drying methods, thus furthering olive pomace's potential valorization as a food ingredient.