Concentrations Of Hydroxytyrosol Research Articles

The Mediterranean Diet in Pregnancy: Implications for Maternal Brain Morphometry in a Secondary Analysis of the IMPACT BCN Randomized Clinical Trial

Introduction: A Mediterranean diet has positive effects on the brain in mid-older adults; however, there is scarce information on pregnant individuals. We aimed to evaluate the effect of a structured Mediterranean diet intervention on the cortical structure of the maternal brain during pregnancy. Methods: This study was a secondary analysis of the IMPACT BCN, a randomized clinical trial with 1221 high-risk pregnant women randomly allocated into three groups at 19–23 weeks of gestation: Mediterranean diet intervention, a mindfulness-based stress reduction program, or usual care. Maternal brain magnetic resonance imaging was performed during the third trimester of pregnancy in a random subgroup of participants. For this study, data from the Mediterranean diet and usual groups were analyzed. Maternal dietary intake, adherence to the Mediterranean diet and metabolite biomarkers were evaluated using a food frequency questionnaire, a 17-item dietary screener and plasma/urine samples, respectively. Results: The cluster-wise analysis showed that the Mediterranean diet group participants (n = 34) had significantly larger surface areas in the right precuneus (90%CI: <0.0001–0.0004, p < 0.001) and left superior parietal (90%CI: 0.026–0.033, p = 0.03) lobules compared to the usual care group participants (n = 37). A larger right precuneus area was associated with high improvements in adherence to the Mediterranean diet, a high intake of walnuts and high concentrations of urinary hydroxytyrosol. A larger left superior parietal area was associated with a high intake of walnuts and high concentrations of urinary hydroxytyrosol. Conclusions: The promotion of a Mediterranean diet during pregnancy has a significant effect on maternal brain structure.

The Production of Bioactive Hydroxytyrosol in Fermented Beverages: The Role of Must Composition and a Genetically Modified Yeast Strain

Hydroxytyrosol (HT) is a well-known compound for its bioactive properties. It is naturally present in olives, olive oil, and wine. Its presence in wines is partly due to its production during alcoholic fermentation by yeast through a hydroxylation of tyrosol formed through the Ehrlich pathway. This work aims to explore the influence of yeast assimilable nitrogen (YAN) and glucose content as precursors of HT formation during alcoholic fermentation. Commercial Saccharomyces cerevisiae QA23 and its metabolically engineered strain were used to ferment synthetic must. Each strain was tested at two different YAN concentrations (210 and 300 mg L−1) and two glucose concentrations (100 and 240 g L−1). This work confirms that the less YAN and the more glucose, the higher the HT content, with fermentations carried out with the metabolically engineered strain being the ones with the highest HT content (0.6 mg L−1).

Covalent modification of soy protein isolates by hydroxytyrosol: Effects on structural and functional properties of adducts

The effect of covalent binding of different concentrations of hydroxytyrosol (HT) to soy protein isolate (SPI) by enzymatic method on the structure and function of the complex was investigated. Polyphenol binding rate increased and then decreased with increasing hydroxytyrosol concentration, with a maximum binding rate of 38.10 ± 1.08%. Covalent binding to HT resulted in a significant increase in the turbidity of the adduct and a significant decrease in the free sulfhydryl content and surface hydrophobicity. The structure of the adduct was altered and the α-helix structure was converted to a β-sheet one. The maximum foaming property of the adducts was observed at a HT concentration of 40 μmol/g, which was 28.84% higher than the control SPI. The adduct had maximum solubility (52.84 ± 0.18%) at HT concentration of 50 μmol/g. The emulsifying properties of the adducts were maximized at a hydroxytyrosol concentration of 60 μmol/g. When the HT concentration was 70 μmol/g, the DPPH and ABTS radical scavenging rates of the adducts were increased by 245.03% and 26.35%, respectively, compared with the control SPI.

Interaction of soy protein isolate with hydroxytyrosol based on an alkaline method: Implications for structural and functional properties

This study investigated the effect of different concentrations of hydroxytyrosol (HT) covalently bound to soy protein isolate (SPI) by the alkaline method on the structure and function of the adducts. The amount of polyphenol bound to SPI first increased to a maximum of 42.83 % ± 1.08 % and then decreased. After the covalent binding of HT to SPI, turbidity and in vitro protein digestibility increased and decreased significantly with increasing concentrations of HT added, respectively, and the structure of SPI was changed. The adducts had a maximum solubility of 52.52 % ± 0.33 %, and their water holding capacity reached a maximum of 8.22 ± 0.11 g/g at a concentration of 50 μmol/g of HT. Covalent modification with HT significantly increased the emulsifying and foaming properties and antioxidant activity of SPI; the DPPH and ABTS radical scavenging rates increased by 296.89 % and 33.80 %, respectively, at a concentration of 70 μmol/g of HT.

Evaluation of the effects of hydroxytyrosol on human sperm parameters during cryopreservation

Human sperm cryopreservation is a routine procedure in assisted reproductive technology, but it has detrimental effects on different sperm parameters due to oxidative stress. Our objective was to assess the impacts of hydroxytyrosol (HT), as an antioxidant, on human sperm parameters following cryopreservation. In the first phase, 20 normal human semen samples were cryopreserved using the rapid freezing method with different concentrations of HT including 0, 50, 100, 150, and 200 μg/mL. In the second phase, 20 normal semen samples were collected and cryopreserved with 50 and 100 μg/mL HT. The beneficial effects of HT were determined by evaluation of motility (computer-assisted sperm analysis; CASA), viability (Eosin-nigrosine stain), DNA integrity (sperm chromatic dispersion test, SCD), reactive oxygen species (DCF and DHE staining by flowcytometry) lipid peroxidation (malondialdehyde, MDA test) and mitochondrial membrane potential (JC1 staining by flowcytometry) of sperm after cryopreservation. After thawing, sperm motility had an increasing trend in 50 and 100 μg/mL HT groups in comparison with other groups, althought the difference was not significant. However, sperm viability was significantly increased at 50 and 100 μg/mL HT. Our data also showed that sperm DNA fragmentation was significantly decreased after thawing at 100 μg/mL in comparison with 0 and 50 μg/mL HT. However, the level of intracellular reactive oxygen species, lipid peroxidation and mitochondrial membrane potential were not significantly different between groups. Our results showed that HT may have protective effects on the viability and DNA integrity of human sperm during the freezing-thawing process.

Boric acids decorated polymers with Au nanoparticle anchor assisted laser desorption/ionization for qualitive and quantitative analysis of hydroxytyrosol in red wines

Hydroxytyrosol possesses a variety of biological and pharmacological activities that are beneficial to human health. However, the methodologies for its detection always suffered from problems. In this work, the gold nanoparticle modified polymer decorated with boric acids (pMBA/VPBA@Au) was synthesized and used both as the adsorbent and matrix to enrich and ionize small molecule substances through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The pMBA/VPBA@Au displayed a low detection limit (8 × 10−6 M) and high selectivity (1:100) for the enrichment of hydroxytyrosol, and the linear correlation curve between the concentration of hydroxytyrosol and the intensity of MS had a good correlation (10−4-10−2 M, R2 = 0.997). Additionally, the pMBA/VPBA@Au was used to quantify hydroxytyrosol in red wines, and the contents were 0.053–0.094 μg/mL. In general, a simple and novel method for the detection of hydroxytyrosol by SALDI-MS using boric acid functionalized polymer was developed for the first time, showing a good practical application value.

Optimizing the Integration of Microwave Processing and Enzymatic Extraction to Produce Polyphenol-Rich Extracts from Olive Pomace.

The integration of green technologies such as microwave- and enzyme-assisted extraction (MEAE) has been shown to improve the extraction efficiency of bioactive compounds while reducing processing time and costs. MEAE using tannase alone (MEAE-Tan), or in combination with cellulase and pectinase (MEAE-Tan-Cel-Pec), was optimized to produce enriched phenolic and antioxidant extracts from olive pomace. The individual and integrated impact of enzyme concentration, temperature, and pomace/water ratio were determined using a central composite rotatable design. Optimal extraction conditions for MEAE-Tan (60 °C, 15 min, 2.34% of enzyme (w/w), and 1:15 pomace/water ratio) and MEAE-Tan-Cel-Pec (46 °C, 15 min, 2% of enzymes (w/w), in the proportion of 1:1:1, and 1:20 pomace/water ratio) resulted in extracts containing 7110.6 and 2938.25 mg GAE/kg, respectively. The antioxidant activity of the extracts was correlated with phenolic acid release, which was enzyme-dependent, as determined with HPLC-DAD analysis. Enzyme selection had a significant impact on the phenolic profile of extracts, with tannase releasing high concentrations of chlorogenic acid and the combined use of enzymes releasing high concentrations of hydroxytyrosol and chlorogenic and ferulic acids. The novelty of this study relies on the integration and optimization of two green technologies (microwave- and enzyme-assisted extraction) to improve the extraction efficiency of bioactive phenolics from olive pomace while reducing processing time and costs. While these techniques have been evaluated isolated, the benefits of using both processing strategies simultaneously remain largely unexplored. This study demonstrates the effectiveness of the integration and processing optimization of two environmentally friendly technologies as a promising alternative to treat agro-industrial byproducts.

Modeling the antimicrobial effects of olive mill waste extract, rich in hydroxytyrosol, on the growth of lactic acid bacteria using response surface methodology.

The objective of this study is to assess the inhibitory effects of an aqueous extract from olive oil mill waste (alperujo) on the growth of a lactic acid bacteria (LAB) cocktail consisting of various strains of Lactiplantibacillus pentosus and Lactiplantibacillus plantarum species. For this purpose, response surface methodology was employed using two independent variables (pH levels 3.5-5.55; hydroxytyrosol concentration ranging from 0.93-2990ppm). The response variable was the average inhibition per treatment on the LAB cocktail (expressed as a percentage). The developed model identified significant terms, including the linear effect of hydroxytyrosol and pH, their interaction, and the quadratic effect of pH. Maximum inhibition of the LAB cocktail was observed at progressively higher concentrations of hydroxytyrosol and lower pH values. Therefore, complete inhibition of LAB in the synthetic culture medium could only be achieved for concentrations of 2984ppm hydroxytyrosol at a pH of 3.95. These findings suggest that extracts derived from "alperujo" could be utilized as a natural preservative in acidified foods with a bitter flavor and antioxidant requirements.

Strategies for the purification of hydroxytyrosol-rich extracts obtained from exhausted olive pomace

Exhausted olive pomace (EOP) is a residual biomass from which hydroxytyrosol can be recovered. This compound has applications in the food/pharma sectors, but its extraction yields complex extracts that require further purification for some applications.This work explores purification strategies based on membrane technology, liquid–liquid extraction (LLE), and solid-phase extraction with adsorbents and resins. The hydroxytyrosol content, phenolic profile, antioxidant activity, and inhibition of α-glucosidase and α-amylase were monitored. Hydroxytyrosol stood out in all purified extracts. The best hydroxytyrosol recovery (88.8%) was achieved using LLE with ethyl acetate as the extractant, while the purest extracts in phenolic compounds, including hydroxytyrosol, were obtained using the latter solvent and C18 (529 mg/g), DSC-8 (873 mg/g), and Purosorb PAD910 (523 mg/g). Conversely, mannitol and glucose, at high concentrations in the extract, were selectively retained in the aqueous phases.The developed strategies are discussed regarding their suitability to provide hydroxytyrosol-concentrated extracts, up to 291 mg/g, with antioxidant and antidiabetic functionalities.

Anti-Inflammatory Effects of Nutritionally Relevant Concentrations of Oleuropein and Hydroxytyrosol on Peripheral Blood Mononuclear Cells: An Age-Related Analysis.

Immunosenescence and inflammaging facilitate the insurgence of chronic diseases. The Mediterranean diet is a non-invasive intervention to improve the chronic low-grade inflammatory status associated with aging. Olive oil oleuropein (OLE) and hydroxytyrosol (HT) demonstrated a controversial modulatory action on inflammation in vitro when tested at concentrations exceeding those detectable in human plasma. We studied the potential anti-inflammatory effects of OLE and HT at nutritionally relevant concentrations on peripheral blood mononuclear cells (PBMCs) as regards cell viability, frequency of leukocyte subsets, and cytokine release, performing an age-focused analysis on two groups of subjects: Adult (age 18-64 years) and Senior (age ≥ 65 years). OLE and HT were used alone or as a pre-treatment before challenging PBMCs with lipopolysaccharide (LPS). Both polyphenols had no effect on cell viability irrespective of LPS, but 5 µM HT had an LPS-like effect on monocytes, reducing the intermediate subset in Adult subjects. OLE and HT had no effect on LPS-triggered release of TNF-α, IL-6 and IL-8, but 5 µM HT reduced IL-10 secretion by PBMCs from Adult vs. Senior group. In summary, nutritionally relevant concentrations of OLE and HT elicit no anti-inflammatory effect and influence the frequency of immune cell subsets with age-related different outcomes.

Supramolecular-solvent based extraction of hydroxytyrosol from brines of the processing of table olives

The recovery of bioactive compounds from agri-food waste is a growing sector and in line with the principles of green chemistry. In the last two decades, the development of processes for the extraction and purification of bioactive compounds that are cheaper, faster, simple, efficient, safe and ecological has been investigated. In this study, we develop for the first time a simple liquid–liquid extraction method of hydroxytyrosol from brines of the processing of table olives, an abundant and underutilized waste of the olive industry as alternative to nanofiltration and sorption onto resins. Brines contain a high concentration of phenolic compounds with beneficial health properties, the major compound being hydroxytyrosol. For the extraction of hydroxytyrosol from brines, green supramolecular solvents (SUPRASs) made up of 1,2-hexanediol and water and induced by salts (Na2SO4 and sodium citrate) were used, all innocuous and authorized ingredients for use in the cosmetic industry. The extraction process of hydroxytyrosol from brines was optimized (in terms of the amount of 1,2-hexanediol and salt for the synthesis of SUPRAS). The highest concentrations of hydroxytyrosol in the SUPRAS extracts (∼0.5–0.9% w/w) were obtained with 4.8% v/v of 1,2-hexanediol and 1 M of Na2SO4 for synthesis (equivalent to a SUPRAS:sample ratio of 1:20 v/v in the extraction process). The final extracts were further analyzed by liquid chromatography and high resolution mass spectrometry to identify other compounds of interest.

Effect of debittering process by the lye instead of NaOH on phenolic components and sensory properties of pickled olive fruits

In this study, the effect of debittering methods (normal water, brine, oak ash and NaOH) on the phenolic compounds and sensory properties of olives in the production of pickled olives was investigated. The hydroxytyrosol contents of the control group olives of Ayvalık and Gemlik olives were determined as 92.37 and 67.73 mg/100 g, respectively. The hydroxytyrosol contents of scratched fermented “Ayvalık” olives debittered in normal water, brine, oak ash and NaOH were detected between 30.49 (0.day) to 58.0 mg/100 g (30.day), 24.41 (10.day) to 80.43 mg/100 g (0.day), 37.75 (45.day) to 94.51 mg/100 g (60.day) and 17.52 810.day) to 27.49 mg/100 g (30.day). In addition, hydroxytyrosol amounts of crushed fermented “Ayvalık” olives according to the same bitterness removal order were identified between 45.53 (60.day) to 89.15 mg/100 g (30.day), 41.85 (10.day) to 117.71 mg/100 g (45.day), 33.15 (10.day) to 71.30 mg/100 g (45.day) and 17.36 (0.day) to 25.90 mg/100 g (10.day), respectively. The oleuropein contents of the control groups of “Ayvalık” and “Gemlik” olive cultivars were determined as 108.33 mg/100 g and 81.81 mg/100 g, respectively. In addition, oleuropein contents of whole fermented “Ayvalık” olives changed between 54.61 (60.day) and 55.42 mg/100 g (45.day), 55.35 (30.day) and 55.67 mg/100 g (60.day), 55.07 (10.day). and 55.59 mg/100 g (30.day) and 14.97 (0.day) to 18.14 mg/100 g (10.day). The highest decreasing components were hydroxytyrosol, tyrosol, caffeic acid and oleuropein. In general, the phenolic content of olives on the 0th day of fermentation was slightly higher than the other days of fermentation. In general, the sensory properties of whole, scratched and crushed "Ayvalı" and "Gemlik" olives on the 45th day of fermentation were most appreciated by the panelists. In addition, the sensory values of all olives treated with NaOH were not appreciated by the panelists.

Ultrasound-Assisted Extraction of Hydroxytyrosol from Lactiplantibacillus plantarum Fermented Olive Leaves: Process Optimization and Bioactivity Assessment

Olive leaves are important by-products for the recovery of phenolic compounds and extracts with high phenolic content using lactic acid bacteria during fermentation. Lactiplantibacillus plantarum (L. plantarum) strains as glucosidase-positive strains are starter cultures used to control the fermentation process. The main objective of the present work is to determine the most effective strain for the biodegradation of oleuropein to hydroxytyrosol using two L. plantarum strains for the fermentation of olive leaves. Box–Behnken experimental design was applied to determine the optimum ultrasound-assisted extraction (UAE) conditions to obtain hydroxytyrosol-rich extract using the brine of the fermented leaves. L. plantarum ATCC 14917 (hydroxytyrosol; 126.89 ± 1.59 mg/L) strain showed higher oleuropeinolytic activity than L. plantarum ATCC-BAA 793 (85.93 ± 0.70 mg/L) in olive leaf brine. When the UAE method was applied, it was seen that the hydroxytyrosol concentration of samples that were inoculated with L. plantarum ATCC 14917 (362.29 ± 2.31 mg/L) compared to L. plantarum ATCC-BAA 793 (248.79 ± 4.14) increased. The optimum UAE conditions were determined as 30% amplitude-5 min-30% ethanol for ATCC 14917 and 45% amplitude-9 min-10% ethanol for BAA 793 strain. This study showed that the brines of fermented olive leaves with oleuropeinolytic strains can be considered high added value products.

The Effect of Hydroxytyrosol in Type II Epithelial-Mesenchymal Transition in Human Skin Wound Healing.

Skin wound healing is a multiphase physiological process that involves the activation of numerous types of cells and is characterized by four phases, namely haemostasis, inflammatory, proliferative, and remodeling. However, on some occasions this healing becomes pathological, resulting in fibrosis. Epithelial mesenchymal transition (EMT) is an important process in which epithelial cells acquire mesenchymal fibroblast-like characteristics. Hydroxytyrosol (HT) is a phenolic compound extracted from olive oil and has been proven to have several health benefits. The aim of this study was to determine the effect of HT in type II EMT in human skin wound healing via cell viability, proliferation, migration, and proteins expression. Human dermal fibroblasts (HDF) isolated from skin samples were cultured in different concentrations of HT and EMT model, induced by adding 5 ng/mL of transforming growth factor-beta (TGF-β) to the cells. HT concentrations were determined via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cells' migrations were evaluated using scratch and transwell migration assay. Protein expressions were evaluated via immunocytochemistry. The result showed that HT at 0.2% and 0.4% significantly increased the proliferation rate of HDF (p < 0.05) compared to control. Scratch assay after 24 h showed increased cell migration in cells treated with 0.4% HT (p < 0.05) compared to the other groups. After 48 h, both concentrations of HT showed increased cell migration (p < 0.05) compared to the TGF-β group. Transwell migration revealed that HT enhanced the migration capacity of cells significantly (p < 0.05) as compared to TGF-β and the control group. In addition, HT supplemented cells upregulate the expression of epithelial marker E-cadherin while downregulating the expression of mesenchymal marker vimentin in comparison to TGF-β group and control group. This study showed that HT has the ability to inhibit EMT, which has potential in the inhibition of fibrosis and persistent inflammation related to skin wound healing.

Recovery and valorization of food industry by-products through the application of Olea europaea L. leaves in kombucha tea manufacturing

The present study investigated the application of a sustainable production model to the manufacturing technology of kombucha. In order to comply with the principles of circular economy, a newly-formulated beverage, obtained through the use of olive mill by-products as a fermentation substrate, was examined. The total polyphenol content, antioxidant activity and sensory profile of the final product was analyzed with the intention of evaluating the bioactive and sensory contribution made by olive leaves, when used in substitution of tea for kombucha fermentation. The initial level of oleuropein (394.7 mg/L) obtained in the olive leaves extract did not inhibit the natural fermentation process of Symbiotic Culture of Bacteria and Yeast (SCOBY). The addition of increasing percentages of the by-product during the fermentation produced several kombucha samples rich in secoiridoid bioactive compounds with a concentration of oleuropein and hydroxytyrosol ranged from 306.4 mg/L to 91.2 mg/L and from 29.0 mg/L to 9.3 mg/L, respectively. Since tea stands out as one of the main cost items in kombucha tea manufacturing, this study demonstrated that the use of olive leaves, as a polyphenol-rich substrate, may represent a viable strategy to valorize the agro-industrial waste, reduce production costs, preserve the antioxidant properties of kombucha and enrich its sensory profile.

Comparative Study on Chemical Composition of Green and Black Table Olives Brines of the Endemic ''Sigoise'' Cultivar: Recovery of high-Added Values Compounds.

The effluents derived from the processing of table olives stand for a serious environmental problem. The study aims to valorize the brine water of table olives at different stages of ripening (green and black) of the Algerian variety Sigoise of Bejaia (East) and Mascara (West). The physico-chemical characterization revealed that these samples display have a high acid pH and salinity. The comparative study of phenolic levels exhibited showed very significant differences between the brine waters of green olives from Bejaia and Mascara, while the brines of black olives presented showed comparable levels. A high strong antioxidant potential was confirmed by DPPH (CI50 =0.35 μg/100 ml-0.50 μg/100 ml) and FRAP (CI50 =626.89 μg/100 ml-875.54 μg/100 ml) tests. Chemical screening by HPLC-DAD of the four samples identified high concentrations of hydroxytyrosol (HT) (390.4 mg/100 ml-360.8 mg/100 ml) and tyrosol (202.2 mg/100 ml-101.4 mg/100 ml). This study provided a deeper insight into the phenolic profile and the antioxidant potential of these brines.

Hydroxytyrosol's effect on the expression of apoptosis and oxidative stress related genes in BE (2)-C neuroblastoma cell line

Neuroblastoma (NB) is defined as a type of tumor that involves the autonomic nervous system. Oxidative stress (OxS) resulted from dopamine (DA) oxidation and the reduction of antioxidant enzyme activity is the main reason for the initiation and progression of NB. The aim of this study was the evaluation of the protective effects of Hydroxytyrosol (HT) against OxS induced by H2O2. In the present in vitro study, the OxS condition was induced by H2O2 treatment of BE (2)-C cells; then, the cells were treated by several concentrations of HT and Vitamin C (VC). Next, the expression levels of genes related to OxS and apoptosis were measured through the RT-qPCR method. Subsequently, the activity of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) was determined via enzyme colorimetric assay. Finally, the level of malondialdehyde (MDA) was measured by the Thiobarbituric acid reactive substances (TBARS) assay. HT treatment leads to a significantly decreased the expression level of Bax, caspase-3, and p53 (p < 0.05); as well, the expression levels of Nrf-2, SOD, Bcl-2, PPAR-γ, CAT, and GPx were increased at a significant manner (p < 0.05). Moreover, HT treatment led to a remarkable increase in the enzyme activity of CAT, SOD, and GPx (p < 0.001). Finally, the MDA levels were significantly reduced (p < 0.001) in BE (2)-C cells after HT treatment. The findings suggest that HT could have neuroprotective effects by enhancing various enzymatic and molecular pathways to increase the cellular antioxidant defense. Additionally, HT reduced the expression of the P53 gene and blocked the apoptotic signaling pathways by suppressing Bax and caspase-3. However, further animal models studies are needed to approve the beneficial effects of HT.

Characterization and Comparison of Extra Virgin Olive Oils of Turkish Olive Cultivars.

Extra virgin olive oils (EVOOs) obtained from five Turkish olive cultivars widely produced in the Aegean and Marmara regions were investigated based on their total antioxidant capacity (TAC), total phenolic content (TPC), pigment contents, fatty acid (FA) profiles, phenolic compounds (PC), volatile compounds (VC), and sensory properties. The results showed that all properties of EVOO samples were significantly affected by the olive cultivar used. The pigment contents in Ayvalık (9.90 mg·kg-1) and Uslu (9.00 mg·kg-1) oils were higher than the others (p < 0.05). The greatest values for oleic acid (74.13%) and TPC (350.6 mg·kg-1) were observed in Gemlik and Domat oils, respectively (p < 0.05). Edincik oil showed the maximum hydroxytyrosol content (48.022 mg·kg-1) and TAC value (515.36 mg TE·kg-1) (p < 0.05). The Edincik, Domat, and Uslu oils were significantly not different for the total content of C6 compounds derived by lipoxygenase, which are the main volatiles responsible for the typical aroma of EVOOs (p > 0.05). Domat oil also exhibited the highest scores for bitterness and pungency perceptions (p < 0.05). The fruitiness scores of the oil samples (except for Ayvalık oil) were close to each other, even if they were statistically different (p < 0.05). Principal component analysis (PCA) indicated that the Ayvalık oil was separated from the others due to its poor-quality characteristics. As a result, it can be stated that Domat olive oil has better quality than the others.

Protective Effect of Treated Olive Mill Wastewater on Target Bacteria and Mitochondrial Voltage-Dependent Anion-Selective Channel 1.

Olive mill wastewater, a by-product of the olive oil industry, represents an important resource, rich in bioactive compounds with antioxidant activity. In this study, two strategies to concentrate the bioactive components were used: the tangential membrane filtration (ultrafiltration and reverse osmosis) and the selective resin extraction. The concentrates were evaluated for physico-chemical characteristics and antioxidant activity. Furthermore, the antimicrobial activity and the effect on the mitochondrial voltage-dependent anion selective channel 1 were evaluated. The chemical results highlighted that the highest concentration of hydroxytyrosol (as 7204 mg/L) was revealed in the sample obtained by inverse osmosis while the highest concentration of oleuropein (10005 mg/L) was detected in the sample obtained by resin extraction. The latter sample exhibited the highest antimicrobial effects against Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Both samples exhibited a high impact on the electrophysiological parameters of VDAC1 activity. These results showed that both valorization techniques, which can be reproduced at industrial scale, provided phenolic concentrates with antioxidant and antimicrobial activity useful for different future perspectives.

Investigation and quantification of the potential antioxidant, inflammatory, and antibacterial bioactive molecules of the extracts of Algerian black and green table olive brine

The table olive industry produces a large amount of wastewater that can be expensive to be treated and harmful to the environment. This study aimed to find a way to reuse brine water from the production of black and green table olive brines from Bejaia and Mascara of the Sigoise cultivar in order to create a valuable byproduct and con-tribute to sustainable development. In this context, the high-performance liquid chromatography–diode-array detection (HPLC-DAD) analysis revealed the highest concentration of hydroxytyrosol (4-(2-dihydroxy phenyl ethanol); 69.67 mg/100 mg) for green table olive brines of Mascara (EOGM) and tyrosol (Ty) (28.8 mg/100 mg) for black table olive brines of Bejaia (EOBB). Presence of polyphenols and ortho-diphenols could be responsible for their antioxidant, anti-inflammatory, and antibacterial properties. To assess antioxidant activity, the scavenging effects of DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,20-Azinobis[3-ethylbenzothiazoline-6-sulfonate]) radicals as well as hydrogen peroxide (H2O2) radicals were used. The antimicrobial activity showed that the black olive extract exhibited the best inhibitory effect, with a minimum inhibitory concentration (MIC) ranging from 0.625 mg/mL to 0.31 mg/mL. The anti-inflammatory activity of tested extracts of black olives of Bejaia (EOBB) and green of olives Mascara (EOGM) was 20.06 µg/mL and 20.21 µg/mL, respectively, which demonstrated the anti-inflammatory effect of these extracts on human beings.