Olive Mill Wastewater Extract Research Articles

Assessment of the germination power and α-amylase activity in the soil rhizospheric compartment amended with olive mill waste waters.

Olive mill wastewater (OMWW) was used in ferti-irrigation due to its high water content, as well as its organic and mineral richness. However, this by-product also contains elevated levels of polyphenols, which may pose phytotoxic risks to soil microbiota and plants over time. To address this concern, we conducted a thorough examination of the phenolic composition of OMWW and the phenolic content of amended soils using HPLC analysis. Additionally, we assessed the residual phytotoxicity of OMWW across various soil rhizospheric layers (0-30 cm, 30-60 cm, and 60-90 cm). Standard germination tests were performed using soil extracts with sorghum (Sorghum bicolor) and tomato (Solanum lycopersicum) seeds. We also measured α-amylase activities in the germinated seeds for both species, comparing them to raw OMWW and control soil extracts. HPLC analysis revealed that tyrosol, ferulic acid, and hydroxytyrosol were the predominant phenolic compounds in crude OMWW, while no detectable compounds were found in the soil extracts. Germination tests indicated minimal toxicity in the topsoil amended with OMWW, with a noticeable reduction in residual phytotoxicity at greater depths. These results aligned with the α-amylase activity assessments, which demonstrated significantly higher enzyme activity in the deeper soil layers (30-60 cm and 60-90 cm), with no substantial differences compared to control extracts.

Comparative Analysis on Polyphenolic Composition of Different Olive Mill Wastewater and Related Extra Virgin Olive Oil Extracts and Evaluation of Nutraceutical Properties by Cell-Based Studies.

This study reports a comparative analysis of the polyphenolic composition and nutraceutical properties of different olive mill wastewater (OMWW) and corresponding extra virgin olive oil (EVOO) extracts. Specifically, four OMWWs and corresponding EVOOs from cultivars Frantoio (A) and Leccino (B) obtained from different crushing seasons (early-stage (A1 and B1) and later-stage (A2 and B2)) were analyzed. Employing HPLC-DAD and LC-MS methods, the primary polyphenol content was identified and quantified. Overall, OMWW extracts showed a greater polyphenolic content compared to corresponding EVOO extracts, with OMWW B1 displaying the highest levels of polyphenols. The antiradical properties of extracts towards radical species (DPPH, ABTS, O2-, and HOCl-) were demonstrated in vitro, revealing a correlation with polyphenolic content. In fact, OMWW B1 and B2 demonstrated the strongest antiradical activity. Exploring nutraceutical properties of OMWWs, the intestinal permeation of the main polyphenols in a co-culture model (Caco-2 and HT29-MTX cell lines) was assessed, with tyrosol achieving a permeation of almost 60%. Furthermore, the involvement in the inflammation process has been evaluated in cell studies on THP1-derived macrophages by immunocytochemistry, demonstrating that OMWW B1 may exert an anti-inflammatory effect by modulating specific phenotype expression on macrophages. In conclusion, this study provides evidence supporting the reuse of OMWWs as a source of polyphenols with nutraceutical properties.

Effect of a Phytochemical-Rich Olive-Derived Extract on Anthropometric, Hematological, and Metabolic Parameters.

Extra virgin olive oil is a fundamental component of the Mediterranean diet. It contains several molecules that sustain human well-being by modulating cellular metabolism and exerting antioxidant, anti-inflammatory, and anti-ageing effects to protect normal tissues, and it can exert anti-angiogenic and pro-apoptotic effects on cancer cells. Metabolites found in different parts of the olive tree, including leaves, also possess properties that might help in cancer prevention and promote wellness in aging. Olive mill wastewater (OMWW), a liquid residue produced during olive oil extraction, represents an environmental issue. However, it is rich in phytochemicals with potential beneficial properties. Dietary supplements based on OMWW can be produced for nutritional supplementation with advantages to the ecology. This work aims to measure hematochemical, anthropometric, and metabolomic parameters in volunteers taking an OMWW dietary supplement, Oliphenolia® (OMWW-OL). The supplementation of OMWW-OL 25 mL twice daily for 30 days was tested on a pilot cohort of volunteers with characteristics close to metabolic syndrome. Hematochemical, anthropometric, serum biomarkers and serum metabolomic parameters were analyzed before the intervention, at 30 days, and 30 days after stopping consumption. A total of 29 volunteers were enrolled, and 23 completed the study. The participants' parameters at baseline were measured, and then twice daily at 30 days of treatment and 30 days after assumption discontinuation. Although treatment was with an olive derivative, their weight did not increase. Their body mass index, instead of augmenting, slightly decreased, particularly in the women. Also, hydration increased, especially in the women, while blood pressure, glycemia, and insulin decreased. Cholesterol, high-density lipoproteins, and triglycerides were stable, and LDL levels decreased, while vitamin D levels, alongside calcium, perceptibly increased. Albumin also increased. All the values were in support of an equilibrium, with no damaging effects. By mass spectrometry analysis, we also found favorable changes in the vitamin D/histamine and homocysteine/methionine ratios, an increase in a new metabolite of unknown formula, and the vitamin D/unknown metabolite ratio. Supplementation of OMWW-OL has no detrimental effects and might imply the beneficial modulation of several biological parameters. Although this is a small pilot study, with limited potency, it preliminarily suggests that the OMWW extract use could be potentially valuable for people at risk of metabolic syndrome. Some of these parameters could also be relevant in supporting healthy ageing and in cancer prevention.

Olive Mill Wastewater Extract: In Vitro Genotoxicity/Antigenotoxicity Assessment on HepaRG Cells.

Olive mill wastewater (OMWW), with its high level of phenolic compounds, simultaneously represents a serious environmental challenge and a great resource with potential nutraceutical activities. To increase the knowledge of OMWW's biological effects, with an aim to developing a food supplement, we performed a chemical characterisation of the extract using the Liquid Chromatography-Quadrupole Time-of-flight spectrometry (LC-QTOF) and an in vitro genotoxicity/antigenotoxicity assessment on HepaRG ™ cells. Chemical analysis revealed that the most abundant phenolic compound was hydroxytyrosol. Biological tests showed that the extract was not cytotoxic at the lowest tested concentrations (from 0.25 to 2.5 mg/mL), unlike the highest concentrations (from 5 to 20 mg/mL). Regarding genotoxic activity, when tested at non-cytotoxic concentrations, the extract did not display any effect. Additionally, the lowest tested OMWW concentrations showed antigenotoxic activity (J-shaped dose-response effect) against a known mutagenic substance, reducing the extent of DNA damage in the co-exposure treatment. The antigenotoxic effect was also obtained in the post-exposure procedure, although only at the extract concentrations of 0.015625 and 0.03125 mg/mL. This behaviour was not confirmed in the pre-exposure protocol. In conclusion, the present study established a maximum non-toxic OMWW extract dose for the HepaRG cell model, smoothing the path for future research.

Abstract 7298: A nutraceutical supplement derived from olive oil byproducts exhibits potential cancer preventive properties in preclinical studies and increases vitamin D levels

Abstract Introduction: Extra virgin olive oil is a basic component of the Mediterranean diet; it contains several molecules with antioxidant, anti-inflammatory, anti-angiogenic and pro-apoptotic properties against a variety of cancers and influencing cellular metabolism too. Olive mill waste water (OMWW), a liquid residue produced in vast amounts during olive oil extraction, represents an environmental issue but on the other side it is a rich source of phytochemicals with potential health benefits. Particularly, OMWWs are rich in different phenolic compounds, that show promise in preventing the development of several disease disorders, including cancer. We have assessed the anti-angiogenic and anti-tumor properties exerted by a nutraceutical from purified OMWW extract, in in vitro and in vivo models, and evaluated its effect in a human pilot study upon informed consent. Experimental procedures: OMWWs ability to affect cell proliferation and survival on different cancer cell lines was assessed by MTT. OMWWs interference with human umbilical endothelial vein cells (HUVECs) tube formation, migration and invasive capacities was studied by endothelial cell morphogenesis and migration assays. The inhibition of angiogenesis and tumor cell growth was investigated by the matrigel assay and tumour xenograft. To evaluate contribution of potential metabolomic biomarkers, SANIST (surface-activated chemical ionization-electrospray-NIST technology) mass spectrometric data-based platform has been employed on sera from a pilot study (Aiello et al, in preparation). Results: OMWW extract shown a potent inhibitory effect inhibiting cells proliferation of both cancer cell lines and HUVECs.OMWW inhibited several molecular targets expression, including IL8, Angiogenin, mTOR, VEGF, CXCR4, CXCL12 and CXCL8, in tumor cells and in TNF-α-stimulated HUVEC. We nalyzed sera from volunteers, after nutraceutical intervention with Oliphenoliaand we assessed several biological parameters. Endogenous vitamin D was significantly increased, as well as albumin, direct bilirubin, and calcium. We also observed glycemia and potassium decrease after Oliphenolia assumption. A previously unknow form of Vitamin D was also detected by mass spectrometry. Conclusions: OMWW extract has shown a stronger anti-angiogenic and anti-tumor properties, with potential chemo-preventive potentials. Results of human pilot study shows Oliphenolia as a promising and interesting natural dietary supplement, rich in polyphenol compounds, that can exert anti-inflammatory and antioxidant activities. Acknowledgements: This study was supported by a donation from the Fattoria La Vialla di Gianni, Antonio e Bandino Lo Franco - SAS (Arezzo, Italy). We are grateful to Professor Anna Aiello, and Professor Calogero Caruso, Palermo University for the pilot study. Citation Format: Adriana Albini, Luana Calabrone, Francesca Albini, Paola Corradino, Simone Cristoni, Douglas M. Noonan. A nutraceutical supplement derived from olive oil byproducts exhibits potential cancer preventive properties in preclinical studies and increases vitamin D levels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7298.

Olive Mill Waste-Water Extract Enriched in Hydroxytyrosol and Tyrosol Modulates Host-Pathogen Interaction in IPEC-J2 Cells.

The dietary supplementation of olive oil by-products, including olive mill waste-water (OMWW) in animal diets, is a novel application that allows for their re-utilization and recycling and could potentially decrease the use of antibiotics, antimicrobial resistance risk in livestock species, and the occurrence of intestinal diseases. Salmonella serovar typhimurium is one of the most widespread intestinal pathogens in the world, causing enterocolitis in pigs. The aim of this study was to investigate the effect of an OMWW extract enriched in polyphenols (hydroxytyrosol and tyrosol) in the immune response of an intestinal porcine epithelial cell line (IPEC-J2) following S. typhimurium infection. Cells were pre-treated with OMWW-extract polyphenols (OMWW-EP, 0.35 and 1.4 µg) for 24 h and then infected with S. typhimurium for 1 h. We evaluated bacterial invasiveness and assayed IPEC-J2 gene expression with RT-qPCR and cytokine release with an ELISA test. The obtained results showed that OMWW-EP (1.4 µg) significantly reduced S. typhimurium invasiveness; 0.35 µg decreased the IPEC-J2 gene expression of IL1B, MYD88, DEFB1 and DEFB4A, while 1.4 µg down-regulated IL1B and DEFB4A and increased TGFB1. The cytokine content was unchanged in infected cells. This is the first study demonstrating the in vitro immunomodulatory and antimicrobial activity of OMWW extracts enriched in polyphenols, suggesting a protective role of OMWW polyphenols on the pig intestine and their potential application as feed supplements in farm animals such as pigs.

Olive Mill Wastewater Extract as a Potential Mosquito Larvicide.

Olive Mill Wastewater Extract as a Potential Mosquito Larvicide.

Natural Antioxidant-Loaded Nanoemulsions for Sun Protection Enhancement

The aim of this study was to formulate nanodispersions to encapsulate antioxidants extracted from olive mill wastewater (OMW) and phycocyanin extracted from Spirulina maxima to act as enhancers for the skin’s protection against UV radiation. For this purpose, two water-in-oil nanoemulsions were prepared using a low-energy homogenization method. Both systems were based on isopropyl myristate as the continuous phase, while water or a mixture of glycerol and water was used as the dispersed phase. Then, antioxidants extracted from OMW and phycocyanin from Spirulina maxima were encapsulated in the water core of the nanoemulsions. The empty and antioxidant-loaded systems were then structurally studied using dynamic light scattering for the detection of their droplet size and stability over time. Electron paramagnetic resonance (EPR) spectroscopy using adequate probes was applied for the characterization of the surfactants’ monolayer in the presence and absence of antioxidants. It was found that the mean droplet diameter of the emulsions was 200 nm. The nanoemulsions remained stable for over 2 months. The encapsulated antioxidants were assessed for their scavenging activity of a model stable radical by applying EPR spectroscopy. It was found that the loaded systems exhibited an increased antioxidant capacity compared with the empty ones. Finally, the most stable system was added to commercial sunscreen lotions and the overall sun protection factor (SPF) was assessed. The sunscreen lotions that contained the nanoemulsions loaded with OMW extracts or phycocyanin showed an increase in their SPF value.

Up-Cycling of Olea europaea L. Ancient Cultivars Side Products: Study of a Combined Cosmetic-Food Supplement Treatment Based on Leaves and Olive Mill Wastewater Extracts.

In recent years, a reversal of the global economic framework has been taking place: from the linear model, there has been a gradual transition to a circular model where by-products from the agri-food industry are taken and transformed into value products (upcycling) rather than being disposed of. Olive tree pruning represents an important biomass currently used for combustion; however, the leaf part of the olive tree is rich in phenolic substances, including hydroxytyrosol. Mill wastewater is also discarded, but it still contains high amounts of hydroxytyrosol. In this study, cosmetic and food supplement formulations were prepared using biophenols extracted from leaves and wastewater and were tested in a placebo-controlled study on healthy volunteers using a combined cosmetic and food supplement treatment. A significant improvement in skin health indicators (collagen density, elasticity, etc.) and a 17% improvement against Photo-induced Irritative Stimulus was observed.

Comparison of Physicochemical Characteristics and Bioactivity of Olive Oil Mill Wastewaters from Traditional and Water-Saving ARA-Controlled Three-Phase Decanter

Olive mill wastewater (OMW) is one of the most environmentally concerning food processing effluents due to its phytotoxicity. Recently, several bioactive compounds with potential applications in food, pharmaceutical, and agricultural industries have been identified in OMW. This study aimed to compare, for the first time, the physico-chemical characteristics and biological activity of OMW obtained by two different types of three-phase decanters: a traditional one and a water-saving ARA decanter. DPPH, ABTS, FRAP, and β-carotene bleaching tests were used to investigate the antioxidant effects. The inhibition of key enzymes involved in hyperglycemia and hypolipidemia were also assessed. A high concentration of phenolic compounds was found in OMW obtained by the ARA-controlled system. Hydroxytyrosol resulted as the dominant compound, with a content of 502.3 mg/kg. OMW extract obtained by ARA decanter resulted as the most active in the FRAP test, with value of 67.23 µMFe (II)/g. A moderate inhibitory activity was found against α-amylase, α-glucosidase, and lipase enzymes. Data obtained by this study evidenced that the use of the ARA decanter allows for obtaining OMW extract characterized by a higher content of phytochemicals in comparison to those obtained by the traditional phase decanter, and a consequent higher biological activity. At the same time, the use of this equipment allows for the reduction of environment impact.

Valorization of Lyophilized Olive Mill Wastewater: Chemical and Biochemical Approaches

Lipid composition and antioxidant activity have been carried out in order to valorize the composition of olive mill wastewater extracts with different solvents (supercritical carbon dioxide, n-hexane, dichloromethane and ethanol). The antioxidant activity was evaluated using ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picrylhydrazyl) tests. The total phenolics and flavonoid contents were, also, determined. The chemical composition of the extracted oil was established, respectively, by gas chromatography–flame ionization detector and high-performance liquid chromatography methods. The results showed that the oleic acid and equivalent carbon number of forty-eight were the major compounds of the analyzed oils. Residual olive mill wastewater from the Sousse region displayed the highest DPPH radical-scavenging activity (31.10 ± 0.10 μg/mL). The chemical analysis of extracts of OMWs showed that the n-hexane fraction contained an abundance of oleic acid (61.62%) and an equivalent carbon number of forty-eight (53.14%). The best antioxidant activity was determined for the ethanol fraction (14.5 μg/mL). The final results showed a significant difference and variations in polar and apolar components. Moreover, n-hexane extracts showed high percentages of Monounsaturated fatty acids (MUFA) with 64% of OMWs oil composition and the dichloromethane extracts contained the largest amount of flavonoids (160.30 ± 1.70 mg EQ/g DM).

Potential use of the bioactive compounds of the olive mill wastewater: Monitoring the aldehydes, phenolic compounds, and polymerized triacylglycerols in sunflower and olive oil during frying

The current study aims to investigate the application of the olive mill wastewater (OMW) extract (100 ppm) as additive to the refined sunflower oil and olive oil to reduce the formation of the oxidation products during deep frying of chicken and potato. The production of polymerized triacylglycerols (pTAG) and aldehydes was lower during frying in olive oil than in enriched refined oil. The highest percentage of polyunsaturated fatty acids in refined oil exhibits a great tendency to form polymeric compounds. The enrichment of sunflower oil with OMW extract reduces the formation of pTAG and aldehydes, whereas the enrichment of olive oil with OMW extract showed an increase in the formation of pTAG and promoted the biosynthesis of aldehydes whose rate remains significantly lower than that observed in enriched sunflower oil. The production of polymerized and aldehydic compounds was more pronounced when chicken was fried compared with potatoes. For the phenolic alcohols, their degradation was reached at the end of the experimentation. Novelty impact statement Olive mill wastewater (OMW) is a source of bioactive molecules that can be extracted and valorized in several industrial sectors. OMW extract reduces the production of p-TAG and aldehydic products during frying foods in refined sunflower oils Frying of foods in olive oil without any additive is healthier than frying in enriched refined oils.

An Olive Oil Mill Wastewater Extract Improves Chemotherapeutic Activity Against Breast Cancer Cells While Protecting From Cardiotoxicity.

Cardiovascular toxicity in cancer patients receiving chemotherapy remains one of the most undesirable side effects, limiting the choice of the most efficient therapeutic regimen, including combinations of different anticancer agents. Anthracyclines (doxorubicin) and antimetabolites (5-fluorouracil (5-FU), capecitabine) are among the most known agents used in breast cancer and other neoplasms and are associated with cardiotoxic effects. Extra-virgin olive oil (EVOO) is rich in polyphenols endowed with antioxidant cardioprotective activities. Olive mill wastewater (OMWW), a waste product generated by EVOO processing, has been reported to be enriched in polyphenols. In this study, we investigated the activities of polyphenol-rich extract from OMWW, A009, in cooperation with chemotherapy on two breast cancer cell lines, namely, BT459 and MDA-MB-231, in a cardio-oncology perspective. The effects of A009 on cardiac cells were also investigated with and without chemotherapeutic agents. Cell viability was determined on BT459 and MDA-MB-231 (i.e., breast cancer cells) and H9C2 (i.e., rat cardiomyocytes) cells, using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. A spheroids assay was used as a 3D in vitro model on BT459 and MDA-MB-231 cells. For in vivo studies, the murine sponge assay of angiogenesis was used as a model of breast cancer-associated vascularization. The embryo of Danio rerio (zebrafish) was used to detect the cardioprotective activities of the OMWW. We found that the A009 extract exhibited antiangiogenic activities induced by breast cancer cell supernatants and increased T-cell recruitment in vivo. The combination of the OMWW extracts with doxorubicin or 5-FU limited BT459 and MDA-MB-231 cell viability and the diameter of 3D spheroids, while mitigating their toxic effects on the rat H9C2 cardiomyocytes. Cardioprotective effects were observed by the combination of OMWW extracts with doxorubicin in zebrafish embryos. Finally, in human cardio myocytes, we observed 5-FU-induced upregulation of the inflammatory, senescence-associated cytokine IL6 and p16 genes, which expression was reduced by OMWW treatment. Our study demonstrates that the polyphenol-rich purified OMWW extract A009 combined with cancer chemotherapy could represent a potential candidate for cardiovascular protection in breast cancer patients, while increasing the effects of breast cancer chemotherapy.

Evaluation Of The Anticoagulant Effect Of Phenolic Extracts Of Two Olive Mill By-products: Olive Mill Wastewater And Olive Mill Pomace

In the Mediterranean basin, olive oil production represents an important economic sector for some countries. Currently, production is constantly growing and is done at the expense of the environment. In addition to its main product, which is virgin olive oil, it generates two by-products, olive mill pomace (OMP) and olive mill wastewater (OMW). These by-products have heretofore little economic value despite their large constitutions of polyphenols that are of great importance in the pharmaceutical industry. This study aimed to assess the anticoagulant effect of the phenolic extract of OMP and OMW from cold extraction in the region of Khenchela, northeastern Algeria. This activity was chosen for its essential role in the prevention and treatment of cardiovascular diseases and their serious complications, which threaten public health and constitute the leading cause of death worldwide. The extraction of the polyphenols was done by the maceration method. The content of total polyphenols was estimated by the Folin-Ciocalteu method. The amount of flavonoids was determined by the aluminum chloride method. The anticoagulant activity of the polyphenols was evaluated in vitro using the Kaolin-cephalin coagulation time (KCT) and prothrombin time (PT) tests. The coagulation times obtained in normal plasma in the presence of these polyphenols indicated that they exert a great anticoagulant activity. It was very highly significant on both endogenous and exogenous coagulation pathways for OMW extracts and significant for OMP extracts. This activity was observed more for the endogenous pathway of coagulation than the exogenous pathway. In conclusion, the polyphenols of olive oil pomace and olive mill wastewater can be used in the pharmaceutical field as an anticoagulant against the complications of thrombotic diseases.

A Polyphenol-Rich Extract of Olive Mill Wastewater Enhances Cancer Chemotherapy Effects, While Mitigating Cardiac Toxicity.

Cardiovascular toxicity remains one of the most adverse side effects in cancer patients receiving chemotherapy. Extra-virgin olive oil (EVOO) is rich in cancer preventive polyphenols endowed with anti-inflammatory, anti-oxidant activities which could exert protective effects on heart cells. One very interesting derivative of EVOO preparation is represented by purified extracts from olive mill waste waters (OMWW) rich in polyphenols. Here, we have investigated the anti-cancer activity of a OMWW preparation, named A009, when combined with chemotherapeutics, as well as its potential cardioprotective activities. Mice bearing prostate cancer (PCa) xenografts were treated with cisplatin, alone or in combination with A009. In an in vivo model, we found synergisms of A009 and cisplatin in reduction of prostate cancer tumor weight. Hearts of mice were analyzed, and the mitochondria were studied by transmission electron microscopy. The hearts of mice co-treated with A009 extracts along with cisplatin had reduced mitochondria damage compared to the those treated with chemotherapy alone, indicating a cardioprotective role. To confirm the in vivo results, tumor cell lines and rat cardiomyocytes were treated with cisplatin in vitro, with and without A009. Another frequently used chemotherapeutic agent 5-fluorouracil (5-FU), was also tested in this assay, observing a similar effect. In vitro, the combination of A009 with cisplatin or 5-FU was effective in decreasing prostate and colon cancer cell growth, while it did not further reduce growth of rat cardiomyocytes also treated with cisplatin or 5-FU. A009 cardioprotective effects towards side effects caused by 5-FU chemotherapy were further investigated, using cardiomyocytes freshly isolated from mice pups. A009 mitigated toxicity of 5-FU on primary cultures of mouse cardiomyocytes. Our study demonstrates that the polyphenol rich purified A009 extracts enhance the effect of chemotherapy in vitro and in vivo, but mitigates chemotherpy adverse effects on heart and on isolated cardiomyocytes. Olive mill waste water extracts could therefore represent a potential candidate for cardiovascular prevention in patients undergoing cancer chemotherapy.

Antioxidant Properties of Olive Mill Wastewater Polyphenolic Extracts on Human Endothelial and Vascular Smooth Muscle Cells.

This work aims to analyze the chemical and biological evaluation of two extracts obtained by olive mill wastewater (OMW), an olive oil processing byproduct. The exploitation of OMW is becoming an important aspect of development of the sustainable olive oil industry. Here we chemically and biologically evaluated one liquid (L) and one solid (S) extract obtained by liquid–liquid extraction followed by acidic hydrolysis (LLAC). Chemical characterization of the two extracts indicated that S has higher phenol content than L. Hydroxytyrosol and tyrosol were the more abundant phenols in both OMW extracts, with hydroxytyrosol significantly higher in S as compared to L. Both extracts failed to induce cell death when challenged with endothelial cells and vascular smooth muscle cells in cell viability experiments. On the contrary, the higher extract dosages employed significantly affected cell metabolic activity, as indicated by the MTT tests. Their ability to counteract H2O2-induced oxidative stress and cell death was assessed to investigate potential antioxidant activities of the extracts. Fluorescence measurements obtained with the reactive oxygen species (ROS) probe H2DCF-DA indicated strong antioxidant activity of the two OMW extracts in both cell models, as indicated by the inhibition of H2O2-induced ROS generation and the counteraction of the oxidative-induced cell death. Our results indicate LLAC-obtained OMW extracts as a safe and useful source of valuable compounds harboring antioxidant activity.

Microbial Application to Improve Olive Mill Wastewater Phenolic Extracts.

Olive mill wastewater (OMW) contains valuable and interesting bioactive compounds, among which is hydroxytyrosol, which is characterized by a remarkable antioxidant activity. Due to the health claims related to olive polyphenols, the aim of this study was to obtain an extract from OMW with an increased level of hydroxytyrosol by means of microbial enzymatic activity. For this purpose, four commercial adsorbent resins were selected and tested. The beta-glucosidase and esterase activity of strains of Wickerhamomyces anomalus, Lactiplantibacillus plantarum, and Saccharomyces cerevisiae were also investigated and compared to those of a commercial enzyme and an Aspergillus niger strain. The W. anomalus strain showed the best enzymatic performances. The SP207 resin showed the best efficiency in selective recovery of hydroxytyrosol, tyrosol, oleuropein, and total phenols. The bioconversion test of the OMW extract was assessed by using both culture broths and pellets of the tested strains. The results demonstrated that the pellets of W. anomalus and L. plantarum were the most effective in hydroxytyrosol increasing in phenolic extract. The interesting results suggest the possibility to study new formulations of OMW phenolic extracts with multifunctional microorganisms.

Polyphenol-Rich Olive Mill Wastewater Extract and Its Potential Use in Hair Care Products

In this work, the influence of phenol-enriched olive mill wastewater (OMWW) extract on hair growth was investigated in vitro on human follicle dermal papilla cells. OMWW has already shown great potential for use in skincare products, and its high polyphenol content is predestined to have a positive effect on hair growth. The studies included caffeine, a positive modulator of hair growth, and dihydrotestosterone, which causes hair loss in vivo, as controls. The impact of the investigated compounds on hair growth was evaluated by studies on cell viability and proliferation, the release of growth factors (insulin-like growth factor-1 and vascular endothelial growth factor), and the reduction of reactive oxygen species formation. OMWW showed a positive influence on the proliferation of the human follicle dermal papilla cells. Moreover, the extract leads to a significantly increased secretion of insulin-like growth factor-1, and a considerable reduction in reactive oxygen species formation was observed. Overall, our results show that the investigated phenol-enriched OMWW extract is a promising ingredient for hair care to improve hair growth, prevent hair loss due to oxidative stress and maintain a healthy scalp.

Olive mill wastewater polyphenol‐based extract as a vegetable oil shelf life extending additive

Olive mill wastewater (OMW) was used as a source to extract radical scavenging compounds, in order to study their possible valorization as natural antioxidants. Their antioxidant activity (IC50 0.32 µg/ml) was found to be more potent than that of a commercial antioxidant: Ascorbic acid (AA) (IC50 1.91 µg/ml). The olive mill wastewater extract (OMWE) and AA were separately added to two vegetable oils, sunflower oil and rapeseed oil. These oils were then put under simulated storage conditions (accelerated test at 60°C) for 4 weeks. The physicochemical parameters, analysis of fatty acids, phytosterols, and tocopherols were the key parameters used to monitor the evolution of the oxidation state. The results obtained showed that the oils treated with the OMWE underwent oxidative deterioration slower than that of the control (without additives), and that phytosterols and tocopherols content decreased as a function of storage time following first-order kinetics. The use of the OMWE helped reduce the loss of both phytosterols and tocopherols in 4 weeks by half compared to the control samples, with the exception of total phytosterols in rapeseed oil where the loss reduction was not as important (about 2% loss reduction). Practical application Antioxidants are widely used in the food industry, as they prevent the development of rancid aromas that lead to harmful consequences during storage and cooking. The practical implication of the study is that natural radical scavenging compounds extracted from OMW can be efficiently used to enhance the quality and safety of refined oils stored at high temperature conditions.

A Polyphenolic Extract from Olive Mill Wastewaters Encapsulated in Whey Protein and Maltodextrin Exerts Antioxidant Activity in Endothelial Cells.

The aim of the present study was to compare maltodextrin and whey protein as encapsulation carriers for olive mill wastewater (OMWW) phenolic extract for producing antioxidant powder, by using spray drying under 17 different conditions. In some samples, gelatin was also added in the encapsulation mixture. The antioxidant activity was assessed in vitro by using the DPPH•, ABTS•+, reducing power and DNA plasmid strand breakage assays. The results showed that both materials were equally effective for producing antioxidant powder, although by using different conditions. For example, inlet/outlet temperature of the spray drying did not seem to affect the maltodextrin samples’ antioxidant activity, but whey protein samples showed better antioxidant activity at lower temperatures. Gelatin use decreased antioxidant activity, especially in whey protein samples. The two most potent samples, one encapsulated in maltodextrin and the other in whey protein, were examined for their antioxidant effects in human endothelial cells by assessing glutathione (GSH) and reactive oxygen species (ROS) levels. Both samples significantly enhanced the antioxidant molecule of GSH, while maltodextrin sample also decreased ROS. The present findings suggested both materials for encapsulation of OMWW extract for producing antioxidant powder which may be used in food products, especially for the protection from ROS-induced endothelium pathologies.