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Pomegranate pomace (PP) is the solid waste produced in bulk by the pomegranate juice industry which is rich in polyphenols and flavonoids that can replace the hazardous chemical antioxidants/antimicrobials currently used in the agro-food and cosmetics sectors. In the present work, the vacuum microwave assisted extraction (VMAE) of natural antioxidants from raw pomegranate pomace was investigated and successfully optimized at an industrial scale. For the optimization of PP VMAE a novel, highly accurate response surface methodology (RSM) based on a comprehensive multi-point historical design was employed. The optimization showed that the maximum recovery of PP total polyphenols as well as total PP flavonoids were obtained at microwave power = 4961.07 W, water to pomace ratio = 29.9, extraction time = 119.53 min and microwave power = 4147.76 W, water to pomace ratio = 19.32, extraction time = 63.32 min respectively. Moreover, the optimal VMAE conditions on economic grounds were determined to be: microwave power = 2048.62 W, water to pomace ratio = 23.11, extraction time = 15.04 min and microwave power = 4008.62 W, water to pomace ratio = 18.08, extraction time = 15.29 min for PP total polyphenols and PP total flavonoids respectively. The main conclusion of this study is that the VMAE extraction can be successfully used at industrial scale to produce, in economic manner, high added value natural extracts from PP pomace.

Orange pomace (OP) is a solid waste produced in bulk as a byproduct of the orange juice industry and accounts for approximately 50% of the quantity of the fruits processed into juice. In numerous literature references there is information about diverse uses of orange pomace for the production of high-added-value products including production of natural antioxidant and antimicrobial extracts rich in polyphenols and flavonoids which can substitute the hazardous chemical antioxidants/antimicrobials used in agro-food and cosmetics sectors. In this work and for the first time, according to our knowledge, the eco-friendly aqueous vacuum microwave assisted extraction of orange pomace was investigated and optimized at real industrial scale in order to produce aqueous antioxidant/antimicrobial extracts. A Response Surface Optimization methodology with a multipoint historical data experimental design was employed to obtain the optimal values of the process parameters in order to achieve the maximum rates of extraction of OP total polyphenols and/or total flavonoids for economically optimum production at industrial scale. The three factors used for the optimization were: (a) microwave power (b) water to raw pomace ratio and (c) extraction time. Moreover, the effectiveness and statistical soundness of the derived cubic polynomial predictive models were verified by ANOVA.

The aim of the study was to examine the effects of a polyphenolic powder from olive mill wastewater (OMWW) administered through drinking water, on chickens' redox status. Thus, 75 chickens were divided into three groups. Group A was given just drinking water, while groups B and C were given drinking water containing 20 and 50  μ g/ml of polyphenols, respectively, for 45 days. The antioxidant effects of the polyphenolic powder were assessed by measuring oxidative stress biomarkers in blood after 25 and 45 days of treatment. These markers were total antioxidant capacity (TAC), protein carbonyls (CARB), thiobarbituric acid reactive species (TBARS) and superoxide dismutase activity (SOD) in plasma, and glutathione (GSH) and catalase activity in erythrocytes. The results showed that CARB and TBARS were decreased significantly in groups B and C, and SOD decreased in group B compared to that in group A. TAC was increased significantly in group C and GSH was increased in group B, while catalase activity was increased in groups B and C compared to that in group A. In conclusion, this is the first study showing that supplementation of chickens with polyphenols from OMWW through drinking water enhanced their antioxidant mechanisms and reduced oxidative stress-induced damage.

In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition-EC) or 400 g of plain yogurt (control condition-CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05) following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p < 0.05) following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB.

Background/aim: A previous study revealed the improvement of redox status in blood and tissues of young piglets (ablactation period), that consumed feed containing polyphenolic additives from byproducts of processed olive mill wastewater (OMWW). The polyphenolic additives strengthened the antioxidant defense of the piglets. Herein we analyzed the fatty acid (FA) composition of these animals in various tissues., Materials and Methods: The steps followed during the analysis were: Preparation and isolation of byproducts containing polyphenolic compounds from OMWW processing, silage and piglet feed preparation, blood and tissue collection, fatty acid methyl esters synthesis and GC/MS analysis., Results: The young piglets, that consumed feed containing polyphenolic additives from byproducts of processed OMWW, were found to have a decreased ω6/ω3 ratio, compared to samples of the control group. For example, in the quadriceps tissue the control group has a ω6/ω3 ratio of 10.1, while in the polyphenolic group this ratio was decreased to 2.93. Regarding the ratio of UFA/SFA, no significant differences were observed. Finally, the polyphenolic group exhibited almost in all tissues lower values of the ratio of PUFA/MUFA than the control group., (Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

In the present study, a polyphenolic byproduct from olive mill wastewater (OMWW) was used for making piglet feed with antioxidant activity. For examining the antioxidant capacity of the feed, 30 piglets of 20 d old were divided into two groups receiving basal or experimental feed for 30 d. Blood and tissue samples were drawn at days 2, 20, 35 and 50 post-birth. The tissues collected were brain, heart, kidney, liver, lung, quadriceps muscle, pancreas, spleen and stomach. The antioxidant effects of the experimental feed were assessed by measuring oxidative stress biomarkers in blood and tissues. The oxidative stress markers were total antioxidant capacity (TAC), glutathione (GSH), catalase activity (CAT), protein carbonyls (CARB) and thiobarbituric acid reactive species (TBARS). The results showed that piglets fed with diet supplemented with OMWW polyphenols had significantly increased antioxidant mechanisms in blood and the majority of the tested tissues as shown by increases in TAC, CAT and GSH compared to control group. Moreover, piglets fed with the experimental feed exhibited decreased oxidative stress-induced damage to lipids and proteins as shown by decreases in TBARS and CARB respectively. This is the first study in which OMWW polyphenols were used for making pig feed with antioxidant activity., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Potential synergistic action of aqueous extracts of pomegranate peel (PP), avocado peel (AP), and avocado seed (AS) wastes isolated by microwave-assisted extraction were assessed in in vitro and in vivo assays as biocontrol agents against several plant pathogenic fungi. The study findings contribute to the utilization of a value-added industrial byproduct and provide significant value in advancing the development of new plant protecting compositions that benefit from the synergistic effects between two important plant species that contain several natural bioactive compounds. More specifically, the in vitro results proved that the use of 100%-pure (PP) extracted waste affected the mycelium growth of Penicillium expansum. Furthermore, mycelium growth of Aspergillus niger was decreased by 10.21% compared to control after 7 days of growth in medium agar containing 100% AP and extracted waste. Moreover, mycelium growth of Botrytis cinerea was affected by equal volume of avocado extraction wastes (50% peel and 50% seed) only at the first 3 days of the inoculation, while at the seventh day of the inoculation there was no effect on the mycelium growth. Equal volumes of the examined wastes showed decreased mycelium growth of Fusarium oxysporum f.sp. lycopersici by 6%, while Rhizoctonia solani mycelium growth was found to be the most sensitive in PP application. In addition, the in vivo assay shown that PP extract suppresses damage of tomato plants caused by R. solani followed by extracted wastes from AP. Based on the research findings, it can be argued that PP and AP extracts can be used as natural antifungals instead of dangerous synthetic antifungals to effectively treat phytopathogens that cause fruit and vegetable losses during cultivation. [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMWW) is the result of the production of olive oil causing severe water pollution. In recent years, distinguished growing interest in isolation, testing, and utilization of agricultural waste or other sources of plant tissues rich in polyphenols has been arised. In this study, the evaluation of liquid polyphenols obtained from OMWW as natural bio-chemicals against several fungal pathogens on tomato plants was examined. Different concentrations of liquid formed polyphenol (LFP) at 5, 10, 20, and 30% were tested against 10 fungal pathogens causing plant diseases on tomato plants. After 40 d of application, tomato plants were harvested and plant height, number of flowers, plant fresh weight, root fresh weight, dry plant weight and dry root weight were calculated and LFP has presented encouraging results in protecting plants. Furthermore, the encapsulation of a polyphenol in encapsulating agent may help to slow down the degradation and protection from the frequent watering and runoff due to this action. Therefore, in order of major protection resulting from the use of polyphenol against major diseases classified the following phytopathogenic fungi:Botrytis cinerea,Sclerotinia sclerotiorum,andAscochyta lentis. [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMWW) is a byproduct of the olive oil extraction process, characterized by high polluting load and polyphenols content. The treatment of OMWW, using microfiltration and XAD4 resin, results in recovery of polyphenols, and also in an effluent (treated OMWW) with decreased organic load and phytotoxic properties, compared to the initial OMWW. The effects of the treated OMWW (T-OMWW) application on maize kernel yield and quality, and soil quality were investigated through a two-year field experiment. T-OMWW was applied by drip irrigation to maize cultivation using two rates of 25–50 t ha−1 year−1, with the addition of mineral fertilization. Furthermore, a treatment of only T-OMWW applied at the rate of 50 t ha−1 year−1and an only mineral fertilization treatment were used. Maize kernel yield and quality were not significantly different between mineral fertilization and T-OMWW application, hence indicating that T-OMWW could fully substitute mineral fertilization under the conditions of our study. Based on the experimental results, an economic analysis was undertaken in order to evaluate the economic implications of T-OMWW application by drip irrigation to maize production. Three scenarios were investigated: (a) mineral fertilization only, (b) T-OMWW application at the rate of 50 t ha−1 year−1only, and (c) T-OMWW application at the rate of 25 t ha−1 year−1combined with reduced mineral fertilization. The cost analysis showed that T-OMWW application at the rate of 50 t ha−1 year−1was the least expensive of the three scenarios investigated, irrespective of the distance between the olive mill and the farm. The use of the farm tractor and tanker for the T-OMWW transportation was more cost effective than hiring a liquid transport company, for distance up to approximately 20 km. For greater distance, hiring a liquid transport company was more economical. [ABSTRACT FROM AUTHOR]

The commercially available macroporous resin Amberlite FPX66 was evaluated for its capacity to adsorb the polyphenols contained in olive mill wastewater (OMWW). The adsorption was performed in the mode of fixed packed-bed contactor. The effects of OMWW flow rate, temperature, dilution and pH on the resin adsorption capacity were investigated. Polyphenols concentration decreased with time. The pattern of the total polyphenols concentration dependence on time was found to be similar in all cases. The pattern included a very steep section for roughly the first hour of the operation, followed by a second section of decreasing gradient down to a final asymptotic equilibrium limit. Regarding the time required for approaching the equilibrium, this was found to be unaffected by the temperature. On the contrary, the magnitude of the equilibrium concentration was substantially affected by the OMWW temperature presenting an optimum at 40°C. The increase in the OMWW flow rate affected markedly the speed of approaching the equilibrium but not its position. The variation of the total polyphenols concentration with time showed that higher concentrations yielded more rapid kinetics at the initial section, but there was no apparent differentiation of the time required to approach the equilibrium. Acidic pH appeared to be favourable for the adsorption. Finally, a novel modelling approach was developed to simulate the adsorption process kinetics. [ABSTRACT FROM AUTHOR]

The commercially available macroporous resin XAD4 was evaluated for its capacity to adsorb the polyphenols contained in olive mill wastewater (OMWW). The adsorption was performed in the mode of fixed packed bed contactor. The effects of OMWW flow rate, temperature, dilution and pH on the resin adsorption capacity were investigated. Polyphenols concentration decreased with time. The pattern of the total polyphenols concentration dependence on time was found similar in all cases. The pattern included a very steep section for roughly the first 2 h of the operation, followed by a second section of decreasing gradient down to a final asymptotic equilibrium limit. Neither the time required for approaching the equilibrium nor the magnitude of the equilibrium concentration was substantially affected by the OMWW temperature. The increase of OMWW flow rate affected markedly the speed of approaching the equilibrium but not its position. The variation of the total polyphenols concentration showed that higher concentrations yielded more rapid kinetics at the initial section, but no apparent differentiation of the time was required to approach equilibrium. Acidic pH appeared to be favourable for the adsorption. Finally, a novel modelling approach was developed to simulate the adsorption process kinetics. [ABSTRACT FROM AUTHOR]

The present work studied the feasibility of diafiltration for processing olive mill waste water (OMWW). An experimental apparatus, consisted of a tubular membrane accommodation module, a controlled temperature raw material stock tank and a positive displacement pump, was developed to investigate the effects of transmembrane pressure, temperature, membrane type and OMWW dilution on diafiltration flux. Three tubular Ultrafiltration membranes were used, with Molecular Weight Cut Off (MWCO) 8,000, 25,000 and 100,000 Da, respectively. The performance of each one of the three membranes, in terms of UF permeation flux, was studied by using four OMWW:water dilutions (1:2, 1:3, 1:5 and 1:10), at three temperature settings (30, 40 and 60 °C). For each one of the 12 respective combination of temperature and dilution setting, six flux measurements at transmembrane pressure values adjusted within the range of 1-6 bars were taken. The experimental results showed that the overall OMWW diafiltration flux, especially in the case of the membranes with MWCO (Daltons) 25,000 and 100,000, was of high magnitude. This fact creates optimism for the commercial follow-up of the process itself by its use as the main component of a promising hybridic scheme for total handling the OMWW pollution problem in an environmentally friendly and sustainable way, according to the EU adopted environmental principle of zero discharge. [ABSTRACT FROM AUTHOR]

The global interest in the use of plant by-product extracts as functional ingredients is continuously rising due to environmental, financial and health benefits. The latest advances in extraction technology have led to the production of aqueous extracts with high bioactive properties, which do not require the use of organic solvents. The purpose of this study was to optimize the conditions applied for the extraction of pomegranate peels (PP) via a "green" industrial type of vacuum microwave-assisted aqueous extraction (VMAAE), by assessing the potential bioactivity of the extracts (in terms of phenolic content and antioxidant activity), using a response surface methodology. The extraction conditions of temperature, microwave power, time and water/PP ratio were determined by the response surface methodology, in order to yield extracts with optimal total phenolics concentrations (TPC) and high antioxidant activity, based on the IC50 value of the scavenging of the 2,2-diphenyl-1-picrylhydrazyl (DPPH●) radical. The values of the optimum extraction parameters, such as extraction temperature (61.48 and 79.158 °C), time (10 and 12.17 min), microwave power (3797.24 and 3576.47 W) and ratio of water to raw material (39.92% and 38.2%), were estimated statistically for the two responses (TPC and IC50 values), respectively. Under these optimal extraction conditions, PP extracts with high TPC ((5.542 mg Gallic Acid Equivalent (GAE)/g fresh PP))/min and radical scavenging activity (100 mg/L (1.6 L/min)) could be obtained. Our results highlighted that the optimized industrial type of VMAAE could be a promising solution for the valorization of the PP by-products. [ABSTRACT FROM AUTHOR]

The aim of the present work was to investigate the potential prebiotic action of Goji berry powder on selected probiotic bacteria grown in a nutritive synthetic substrate and in simulated gastric and intestinal juices. Different probiotic strains of Bifidobacterium and Lactobacillus were grown in these substrates with or without the addition of encapsulated goji berry extracts of different polysaccharide and polyphenol contents. The results proved that the addition of the extracts promoted the proliferation of probiotic strains and, in particular, increased the number of bacterial colonies of Bifidobacterium animalis subsp. lactis (Bb12), Bifidobacterium longum (Bb46), and Lactobacillus casei by 2, 0.26, and 1.34 (log cfu/mL), respectively. Furthermore, the prebiotic effect seems to be correlated to Goji berry polysaccharides and/or polyphenols, higher contents of which (under the tested concentrations) could increase the stress tolerance of B. lactis and B. longum in a simulated gastrointestinal environment. According to the findings of the present research, it can be suggested that the Goji berry encapsulated extracts could be used as prebiotic additives in food or nutraceuticals, in order to stimulate growth or protect the viability of probiotic strains of Bifidobacterium and Lactobacillus. [ABSTRACT FROM AUTHOR]

Currently, there is a great interest in the production of animal feed with antioxidant activity. The aim of this study was to examine the potential antioxidant effects of a feed supplemented with grape pomace (GP), a winery by-product with high environmental load, in chickens. Broilers of 15 days post birth were separated into two groups fed either with standard diet or with diet supplemented with GP for 35 days. Blood and tissues collections were performed after feeding for 15 and 35 days with the experimental diet (i.e. at 30 and 50 days post birth). Free radical toxicity markers, namely thiobarbituric acid reactive substances, protein carbonyls, total antioxidant capacity, reduced glutathione, catalase activity and rate of H 2 O 2 decomposition were determined in blood and tissues of vital organs. The results indicated that feed supplemented with GP decreased oxidative stress-induced toxic effects and improved chickens’ redox status, and so it may also improve their wellness and productivity. On the other hand, this exploitation of GP may solve problems of environmental pollution in areas with wineries. [ABSTRACT FROM AUTHOR]