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Sami Sayadi - One of the best experts on this subject based on the ideXlab platform.
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Valorisation of Olive Mill Wastewater by enhancement of natural hydroxytyrosol recovery
International Journal of Food Science & Technology, 2014Co-Authors: Manel Hamza, Sami SayadiAbstract:Summary Recovery of natural and simple phenolic compounds with high added value was performed successfully from Olive Mill Wastewater. Three types of Olive Mill Wastewater were assayed in bioconversion at 15 and 40 L in mechanically stirred systems for 2 h at 50 °C. Maximum hydroxytyrosol concentrations of about 1.53, 0.83 and 0.46 g L−1 were obtained in the presence of 5 IU Aspergillus niger β-glucosidase per Milliliter of OMW in North OMW, MSP and MCC, which were 2.70-, 1.38- and 1.77-fold higher than the controls, respectively. Enzymatic pretreatment was followed by two tangential flow membrane separation steps, microfiltration (MF) and ultrafiltration (UF), and concentration procedures for the ultrafiltration permeate. The latter exhibited a COD level of 48.44 g L−1. The UF permeate concentration increased the hydroxytyrosol concentration to 7.2 g L−1. Hence, this innovative work described an environmently friendly process; pilot-scale has allowed producing a new and natural product which obeyed the dietary requirements; it contains some minerals beneficial to health and does not contain heavy metals or chemicals. Overall, this chemical-free large-scale process proved efficient for recovery of natural hydroxytyrosol.
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Review: Effects of Olive Mill Wastewater application on soil properties and plants growth
International Journal Of Recycling of Organic Waste in Agriculture, 2013Co-Authors: Ali Mekki, Abdelhafidh Dhouib, Sami SayadiAbstract:Comparative effects of untreated Olive Mill Wastewater (UOMW), treated Olive Mill Wastewater (TOMW) and bioaugmented Olive Mill Wastewater (BOMW) on soil properties, on seeds germination and on plants growth were investigated.
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Changes in the Content of Bioactive Polyphenolic Compounds of Olive Mill Wastewater by the Action of Exogenous Enzymes
Journal of agricultural and food chemistry, 2011Co-Authors: Manel Hamza, Sonia Khoufi, Sami SayadiAbstract:The aim behind the present research is to develop an enzymatic treatment for Olive Mill Wastewater (OMW) to release high amounts of simple phenolics having high antioxidant value. OMW was hydrolyze...
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pilot scale hybrid process for Olive Mill Wastewater treatment and reuse
Chemical Engineering and Processing, 2009Co-Authors: Sonia Khoufi, Fathi Aloui, Sami SayadiAbstract:Abstract A novel process has been developed at pilot scale for the treatment of Olive Mill Wastewater (OMW), which combines electro-Fenton, anaerobic digestion and ultrafiltration. Application of electro-Fenton procedure in semi-continuous mode permitted high removal efficiencies of chemical oxygen demand (COD) (50%) and monophenolic compounds (95%). This pre-treatment was found to enhance the anaerobic activity of an up-flow anaerobic filter (300 l) significantly. In the bioreactor, COD removal efficiency of 75% was reached at a hydraulic retention time of 4.5 d and an organic loading rate of 10 g COD l −1 d −1 . The use of ultrafiltration technology as a post-treatment completely detoxified the anaerobic effluent and removed its high molecular mass polyphenols. An economic calculation of this treatment process revealed that a surplus of energy of 73.5 kWh could be recovered after the treatment of 1 m 3 .
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detoxification of Olive Mill Wastewater by electrocoagulation and sedimentation processes
Journal of Hazardous Materials, 2007Co-Authors: Sonia Khoufi, Firas Feki, Sami SayadiAbstract:Abstract Olive Mill Wastewater (OMW) is characterised by its high suspended solids content (SS), high turbidity (NTU), chemical oxygen demand (COD) concentration up to 100 g l −1 and toxic phenolic compounds concentration up to 10 g l −1 . This study examined the effect of a physico-electrochemical method to detoxify Olive Mill Wastewater prior an anaerobic biotreatment process. The proposed pre-treatment process consisted in a preliminary electrocoagulation step in which most phenolic compounds were polymerised, followed by a sedimentation step. The BOD 5 /COD ratio of the electrocoagulated OMW increased from 0.33, initial value, to 0.58. Furthermore, the sedimentation step yielded the removal of 76.2%, 75% and 71% of phenolic compounds, turbidity and suspended solid, respectively, after 3 days of plain settling. The combination of electrocoagulation and sedimentation allowed a COD reduction and decoloration of about 43% and 90%, respectively. This pre-treatment decreases the inhibition of Vibrio fisheri luminescence by 66.4%. Continuous anaerobic biomethanization experiments conducted in parallel with raw OMW and electrocoagulated OMW before and after sedimentation at a loading rate of 6 g COD l −1 day −1 , proved that the final pre-treated OMW was bioconverted into methane at high yield while raw OMW was very toxic to anaerobic microorganisms.
Charis M Galanakis - One of the best experts on this subject based on the ideXlab platform.
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control of microbial growth in bakery products fortified with polyphenols recovered from Olive Mill Wastewater
Environmental Technology and Innovation, 2018Co-Authors: Charis M Galanakis, Philippos Tsatalas, Zina Charalambous, Ioannis M. GalanakisAbstract:Abstract Polyphenols recovered from Olive Mill Wastewater and other natural antioxidants [ascorbic acid, tocopherols mixture ( α -, β -, γ - and δ -) and α -tocopherol] were mixed in different concentrations with bread and rusks, stored over a period of 20 days and 12 weeks, respectively, and assayed periodically to different microbiological assays (i.e. Total coliforms, Yeasts-Moulds and Bacillus spp.). Antioxidants were able to induce antimicrobial properties in bakery products and subsequently prolong their shelf life. The optimal concentration of Olive polyphenols was this of 200 mg /Kg flour, whereas their emulsification enhanced antimicrobial effect. The formulation of 500 mg α -tocopherol /Kg was also able to extend the shelf life of the bread up to 15 days. Ascorbic acid and tocopherols mixture had did not affect importantly to the overall bread preservation in both assayed concentrations (500 and 1000 mg/Kg). Concerning rusk preservation, α -tocopherol, tocopherols mixture and ascorbic acid were effective at 600 mg/Kg. The results of the study reveal the possibility of polyphenols derived from Olive Mill Wastewater and other natural antioxidants (e.g. α -tocopherol, tocopherols mixture and ascorbic acid) as an antimicrobial agent in foods that undergo oxidative deterioration during cooking (i.e. bakery products).
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Polyphenols recovered from Olive Mill Wastewater as natural preservatives in extra virgin Olive oils and refined Olive kernel oils
Environmental Technology and Innovation, 2018Co-Authors: Charis M Galanakis, Zenovia Charalambous, Philippos Tsatalas, Ioannis M. GalanakisAbstract:This study tests the efficacy of polyphenols (recovered from Olive Mill Wastewater) against ascorbic acid, tocopherols mixture and α-tocopherol for the prevention in oil oxidation. All antioxidants were mixed or emulsified at different concentrations (500–3000 mg/L) with an extra virgin and a refined kernel Olive oil, prior heated in the oven at 100 °C (30 min) and 160 °C (120 min). The activity of antioxidants was monitored using the DPPH* radical scavenging assay and the oxidation of treated oils was monitored by determining peroxide value, p-anisidine values, total polar components, “totox” index and extinction coefficient (K270). Olive polyphenols at 500 and 3000 mg/L reduced the oxidation of both heated oils. Ascorbic acid at 2000 and 3000 mg/L was more efficient than the Olive polyphenols, especially in the case of Olive kernel oil. Tocopherols formulation showed low effectiveness against most oxidation indexes, probably due to their instability at high cooking temperatures. The outcomes of the current study contribute to the further valorization of Olive Mill Wastewater as a source to produce high added-value polyphenols. The latest could be used as preservatives in Olive and vegetable oils as well as in other foods rich in fats, e.g. meat products.
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Implementation of phenols recovered from Olive Mill Wastewater as UV booster in cosmetics
Industrial Crops and Products, 2017Co-Authors: Charis M Galanakis, Philippos Tsatalas, Ioannis M. GalanakisAbstract:Abstract The current study investigates the application of different concentrations of phenols (recovered from Olive Mill Wastewater) as UV booster in cosmetics. The spectrums (220–400 nm) of 0–15 mg Olive phenols/L combined with physical (30 mg TiO2/L) and chemical (5 mg Benzophenone-3, 5 mg Uvinol A, 2 mg Octocrylene, 1 mg OMC and 0.5 mg OC-PABA/L) sunscreen agents were obtained and the in vitro SPF of respective solutions were calculated. In both UVB and UVA regions, absorption of synthetic UV filters increased as a function of Olive phenols concentration, whereas the relationship between SPF increase and Olive phenols concentration was linear. The corresponding equations could be used to estimate the amount of added Olive phenols in order to reach a desirable SPF value and partially replace the amount of synthetic filters in the final product. The entrapment of Olive phenols in silica particles and/or liposomes prior their emulsification in cosmetics was also investigated and resulted in an increase of phenols' water resistance. The results of the current study reveal the potentiality of using Olive Mill Wastewater as a source for the recovery of phenols and their application as UV booster in cosmetics.
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Recovery and Removal of Phenolic Compounds from Olive Mill Wastewater
Journal of the American Oil Chemists' Society, 2014Co-Authors: Neda Rahmanian, Seid Mahdi Jafari, Charis M GalanakisAbstract:Food wastes are today considered as a cheap source of valuable components since the existent technologies allow the recovery of target compounds and their recycling inside the food chain as functional additives in different products. Olive Mill Wastewater (OMW) is generated from Olive oil extraction systems. It has high added-value compounds namely phenolics, recalcitrants, pectin, and some important enzymes. It causes a certain amount of toxicity/phytotoxicity because of its phenolic compounds. OMW also has significant impacts when discharged directly into surface waters. Therefore, the treatment of Olive Mill Wastewater is very much needed. Several types of techniques have been investigated for OMW treatment along with recovery and removal of its phenolic compounds. Among these techniques, physical ones are utilized for extraction purposes, while chemical and biological methods are applied in order to diminish organic load. In this review, current status and recent developments in the recovery and removal of phenolic compounds from OMW have been critically examined.
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Clarification of high-added value products from Olive Mill Wastewater
Journal of Food Engineering, 2010Co-Authors: Charis M Galanakis, Eva Tornberg, Vassilis GekasAbstract:The objective of the current study is to investigate the clarification of two high-added value products (pectin containing solution and phenol containing beverage) recovered from Olive Mill Wastewater. For this purpose, both liquids were processed with four types of ultrafiltration (100, 25, 10 and 2 kDa) and one nanofiltration membranes under optimum transmembrane pressure. Retention coefficients and performance parameters were monitored for each experiment. The membranes of 25 and 100 kDa showed very satisfying results with regard to the concentration of pectin solutions as they were able to separate it from cations and phenols. The membrane of 25 kDa was also able to partially remove the heavier fragments of hydroxycinnamic acid derivatives and flavonols, and simultaneously to sustain the antioxidant properties of the phenol containing beverage in the permeate stream. Finally, nanofiltration clarified the beverage from cations that passed in the permeate stream, but this process resulted in loss of antioxidant compounds, too.
Evan Diamadopoulos - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical treatment of Olive Mill Wastewater
Journal of Chemical Technology & Biotechnology, 2007Co-Authors: Apostolos Giannis, Michael Kalaitzakis, Evan DiamadopoulosAbstract:Background Olive Mill Wastewater (OMW) constitutes a very strong agro-industrial Wastewater posing severe environmental threats in Olive oil producing countries. The main objective of this study was to treat Olive Mill Wastewater by electrochemical oxidation. The variables studied included the type and concentration of electrolyte solutions, voltage and time applied. Results: The electrolyte type and concentration significantly affected the degradation efficiency of the electrochemical oxidation. Optimal conditions for NaCl concentration were 3% (w/v) and 16 V. At these conditions chemical oxygen demand (COD) removal reached 70.8% after 8 h of electrochemical treatment, while color and turbidity were completely removed after short periods of treatment. However, bio-assays indicated that the ecotoxicity of the treated Wastewater remained unchanged, possibly due to the formation of chlorinated by-products. Na2SO4 did not demonstrate sufficient efficiency. The simultaneous use of FeCl3 and NaCl contributed to electro-coagulation of OMW. After settlement, two separate phases were formed: the supernatant phase and the settled solids. Under optimal conditions (2% Na2SO4 + 1% FeCl3; 24 V), the removal efficiency of COD reached 85.5% at the supernatant phase. Conclusion: NaCl was an effective electrolyte for OMW treatment. The electro-coagulation process was also a successful process, but as in the case of NaCl the remaining acute toxicity of treated OMW was high. Copyright © 2007 Society of Chemical Industry
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technologies for Olive Mill Wastewater omw treatment a review
Journal of Chemical Technology & Biotechnology, 2006Co-Authors: Panagiota Paraskeva, Evan DiamadopoulosAbstract:Olive Mill Wastewater (OMW) arises from the production of Olive oil in Olive Mills. It is produced seasonally by a large number of small Olive Mills scattered throughout the Olive oil-producing countries. OMW has a very high organic load, recalcitrant in nature and with a high amount of toxicity/phytotoxicity-associated compounds. Several physicochemical, biological and combined processes have been examined for the treatment of OMW, resulting in considerable organic load and toxicity abatement. Biological processes, aerobic and anaerobic, including anaerobic co-digestion with other effluents and composting, are predominant in the treatment of OMW. Advanced oxidation processes have attracted much attention owing to the strong oxidation potential of the agents used, which can result in a high degree of treatment. Recent research studies employing physical, chemical, biological and combined technologies are reviewed in the current work.
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Sequential anaerobic/aerobic biological treatment of Olive Mill Wastewater and municipal Wastewater
Journal of Chemical Technology & Biotechnology, 2006Co-Authors: Nikolaos Gizgis, Maria Georgiou, Evan DiamadopoulosAbstract:This work investigated the efficiency of the combined anaerobic/aerobic biological co-treatment of Olive Mill Wastewater and primary municipal Wastewater. A laboratory-scale (6.5 L) upflow anaerobic sludge bed reactor received a mixture of Olive Mill Wastewater and primary municipal Wastewater at a loading rate ranging between 3 and 7 kg chemical oxygen demand (COD) m -3 day -1 . The input COD concentration ranged between 1800 and 4400 mg L -1 . The anaerobic reactor was operated at mesophilic conditions (35 °C). The effluent organic load was between 400 and 600 mg COD L -1 , while the suspended solids removal efficiency varied between 75 and 95%. Average biogas production ranged between 3 and 4 L g -1 COD removed. The anaerobic reactor effluent was further treated in a laboratory-scale activated sludge treatment plant. Aerobic treatment reduced the organic load even further to 85-175 mg COD L -1 . However, the final effluent still retained a significant level of colour. Removal of colour was possible by ozonation or coagulation. Finally, the treated effluent was non-ecotoxic, as indicated by the Daphnia magna toxicity test. This treatment method showed that it is feasible to treat Olive Mill Wastewater in a municipal Wastewater treatment plant by means of a high-rate anaerobic reactor located between the primary clarifier and the aeration tank.
Ioannis M. Galanakis - One of the best experts on this subject based on the ideXlab platform.
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control of microbial growth in bakery products fortified with polyphenols recovered from Olive Mill Wastewater
Environmental Technology and Innovation, 2018Co-Authors: Charis M Galanakis, Philippos Tsatalas, Zina Charalambous, Ioannis M. GalanakisAbstract:Abstract Polyphenols recovered from Olive Mill Wastewater and other natural antioxidants [ascorbic acid, tocopherols mixture ( α -, β -, γ - and δ -) and α -tocopherol] were mixed in different concentrations with bread and rusks, stored over a period of 20 days and 12 weeks, respectively, and assayed periodically to different microbiological assays (i.e. Total coliforms, Yeasts-Moulds and Bacillus spp.). Antioxidants were able to induce antimicrobial properties in bakery products and subsequently prolong their shelf life. The optimal concentration of Olive polyphenols was this of 200 mg /Kg flour, whereas their emulsification enhanced antimicrobial effect. The formulation of 500 mg α -tocopherol /Kg was also able to extend the shelf life of the bread up to 15 days. Ascorbic acid and tocopherols mixture had did not affect importantly to the overall bread preservation in both assayed concentrations (500 and 1000 mg/Kg). Concerning rusk preservation, α -tocopherol, tocopherols mixture and ascorbic acid were effective at 600 mg/Kg. The results of the study reveal the possibility of polyphenols derived from Olive Mill Wastewater and other natural antioxidants (e.g. α -tocopherol, tocopherols mixture and ascorbic acid) as an antimicrobial agent in foods that undergo oxidative deterioration during cooking (i.e. bakery products).
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Polyphenols recovered from Olive Mill Wastewater as natural preservatives in extra virgin Olive oils and refined Olive kernel oils
Environmental Technology and Innovation, 2018Co-Authors: Charis M Galanakis, Zenovia Charalambous, Philippos Tsatalas, Ioannis M. GalanakisAbstract:This study tests the efficacy of polyphenols (recovered from Olive Mill Wastewater) against ascorbic acid, tocopherols mixture and α-tocopherol for the prevention in oil oxidation. All antioxidants were mixed or emulsified at different concentrations (500–3000 mg/L) with an extra virgin and a refined kernel Olive oil, prior heated in the oven at 100 °C (30 min) and 160 °C (120 min). The activity of antioxidants was monitored using the DPPH* radical scavenging assay and the oxidation of treated oils was monitored by determining peroxide value, p-anisidine values, total polar components, “totox” index and extinction coefficient (K270). Olive polyphenols at 500 and 3000 mg/L reduced the oxidation of both heated oils. Ascorbic acid at 2000 and 3000 mg/L was more efficient than the Olive polyphenols, especially in the case of Olive kernel oil. Tocopherols formulation showed low effectiveness against most oxidation indexes, probably due to their instability at high cooking temperatures. The outcomes of the current study contribute to the further valorization of Olive Mill Wastewater as a source to produce high added-value polyphenols. The latest could be used as preservatives in Olive and vegetable oils as well as in other foods rich in fats, e.g. meat products.
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Implementation of phenols recovered from Olive Mill Wastewater as UV booster in cosmetics
Industrial Crops and Products, 2017Co-Authors: Charis M Galanakis, Philippos Tsatalas, Ioannis M. GalanakisAbstract:Abstract The current study investigates the application of different concentrations of phenols (recovered from Olive Mill Wastewater) as UV booster in cosmetics. The spectrums (220–400 nm) of 0–15 mg Olive phenols/L combined with physical (30 mg TiO2/L) and chemical (5 mg Benzophenone-3, 5 mg Uvinol A, 2 mg Octocrylene, 1 mg OMC and 0.5 mg OC-PABA/L) sunscreen agents were obtained and the in vitro SPF of respective solutions were calculated. In both UVB and UVA regions, absorption of synthetic UV filters increased as a function of Olive phenols concentration, whereas the relationship between SPF increase and Olive phenols concentration was linear. The corresponding equations could be used to estimate the amount of added Olive phenols in order to reach a desirable SPF value and partially replace the amount of synthetic filters in the final product. The entrapment of Olive phenols in silica particles and/or liposomes prior their emulsification in cosmetics was also investigated and resulted in an increase of phenols' water resistance. The results of the current study reveal the potentiality of using Olive Mill Wastewater as a source for the recovery of phenols and their application as UV booster in cosmetics.
Monem Kallel - One of the best experts on this subject based on the ideXlab platform.
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Treated Olive Mill Wastewater Effects on Soil Properties and Olive Plants
Recent Advances in Environmental Science from the Euro-Mediterranean and Surrounding Regions, 2018Co-Authors: Salma Mseddi, Monem Kallel, Mohamed Zouari, Yosr Smaoui, Leila Chaari, Nada ElloumiAbstract:Olive Mill Wastewater (OMW) production is one of the most serious environmental problems, mainly in countries where Olive oil production is an important economic activity. Its contamination potential is related to its high organic load (COD between 40 and 210 g/L) and the significant concentrations of phenolic compounds (between 0.5 and 24 g/L) which are toxic and ecologically noxious.
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Effects of Olive Mill Wastewater on Soil Nutrients Availability.
2014Co-Authors: Leï La Chaari, Nada Elloumi, Salma Mseddi, Kamel Gargouri, Béchir Bourouina, Taher Mechichi, Monem KallelAbstract:Olive Mill Wastewater (OMW) is one of complex Wastewater generated by the Olive oil extraction process. It is characterized by high values of COD, BOD and phytotoxic levels of polyphenols, but also by a high amount of organic compounds and plant mineral nutrients. Therefore, OMW field spreading may represent a low cost contribution to soil amendment. Olive Mill Wastewater (O MW) spraying effects onto soil physico-chemicals characteristics were investigated. Three OMW doses 50, 100 and 200 m 3 ha -1 year -1 were applied for ten successive years on sandy soil. The findings showed that t he pH of the soil, electrical conductivity and organic matter, total nitrogen, phosphorus, sodium, and potassium s oil contents increased with increased OMW supply. While, no variations were recorded in calcium and magnesium on soil contents.
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Olive Mill Wastewater degradation by Fenton oxidation with zero-valent iron and hydrogen peroxide.
Journal of hazardous materials, 2008Co-Authors: Monem Kallel, Chokri Belaid, Rachdi Boussahel, Mohamed Ksibi, Antoine Montiel, Boubaker ElleuchAbstract:The degradation of Olive Mill Wastewater (OMW) with hydroxyl radicals generated from zero-valent iron and hydrogen peroxide has been investigated by means of chemical oxygen demand (COD) and phenolic compounds analyses. The effects of the H2O2 dose, the pH and the organic matter concentration have been studied. The optimal experimental conditions were found to have continuous presence of iron metal, acid pH (2.0-4.0), and relatively concentrated hydrogen peroxide (9.5M). Coloration of OMW disappeared and phenolic compound decreased to 50% of initial concentration after 3h reaction time. The application of zero-valent Fe/H2O2 procedure permitted high removal efficiencies of pollutants from Olive Mill Wastewater. The results show that zero-valent Fe/H2O2 could be considered as an effective alternative solution for the treatment of OMW or may be combined with a classical biological process to achieve high quality of effluent water.
