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International commercial arbitration is the most preferred dispute resolution method in cross-border commercial disputes. It has been, however, claimed that arbitration has lost its flexibility by becoming increasingly formal and by incorporating litigation practices. In academic literature, this trend has been termed the 'judicialization' of international commercial arbitration. This article argues that while arbitration is becoming progressively judicialized, international commercial courts evidence an opposite, less studied trend; namely, the 'arbitralization' of courts. Through a comparative analysis of different international commercial courts, the article explores how the competition with arbitration has prompted the establishment of these courts, and how arbitration has served as the inspiration for some of their most innovative features. The article concludes that while the incorporation of arbitration features could improve court proceedings, some of international commercial courts' arbitration features undermine procedural justice and the role of courts as public institutions and therefore hit the limits of arbitralization. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) refers to a spectrum of diseases defined by renal fibrosis, permanent alterations in kidney structure, and low glomerular-filtration rate. Prolonged epithelial-tubular damage involves a series of changes that eventually lead to CKD, highlighting the importance of tubular epithelial cells in this process. Lysophosphatidic acid (LPA) is a bioactive lipid that signals mainly through its six cognate LPA receptors and is implicated in several chronic inflammatory pathological conditions. In this report, we have stimulated human proximal tubular epithelial cells (HKC-8) with LPA and 175 other possibly pathological stimuli, and simultaneously detected the levels of 27 intracellular phosphoproteins and 32 extracellular secreted molecules with multiplex ELISA. This quantification revealed a large amount of information concerning the signaling and the physiology of HKC-8 cells that can be extrapolated to other proximal tubular epithelial cells. LPA responses clustered with pro-inflammatory stimuli such as TNF and IL-1, promoting the phosphorylation of important inflammatory signaling hubs, including CREB1, ERK1, JUN, IκΒα, and MEK1, as well as the secretion of inflammatory factors of clinical relevance, including CCL2, CCL3, CXCL10, ICAM1, IL-6, and IL-8, most of them shown for the first time in proximal tubular epithelial cells. The identified LPA-induced signal-transduction pathways, which were pharmacologically validated, and the secretion of the inflammatory factors offer novel insights into the possible role of LPA in CKD pathogenesis. [ABSTRACT FROM AUTHOR]

The scope of the current study was to investigate the efficiency of a two-stage anaerobic-aerobic process for the simultaneous treatment and valorization of selective wastewater streams from a confectionary industry. The specific wastewater (confectionary industry wastewater, CIW) was a mixture of the rinsing eluting during washing of the cauldrons in which jellies and syrups were produced, and contained mainly readily fermentable sugars, being thus of high organic load. The first stage of the process was the dark fermentation (DF) of the CIW in continuous, attached-biomass systems, in which the effect on hydrogen yields and distribution of metabolites were studied for different packing materials (ceramic or plastic), hydraulic retention times, HRTs (12 h–30 h) and feed substrate concentration (20 g COD/L- 50 g COD/L). In the second stage, the effectiveness of the aerobic treatment of the DF effluents was evaluated in terms of the reduction of the organic load and the production of polyhydroxyalkanoates (PHAs) through an enriched mixed microbial culture (MMC). The MMC was developed in a continuous draw and fill system, in which the accumulation potential of PHAs was studied. It was shown that the hydrogen production rates decreased for increasing substrate concentration and HRTs, with a maximum of 12.70 ± 0.35 m3 H 2 /m3 initial CIW achieved for the lowest HRT and feed concentration and using ceramic beads as packing material. Butyrate, acetate and lactate were the main metabolites generated in all cases, in different ratios. The distribution of metabolites during DF was shown to highly affect the efficiency of the second process in terms of both the reduction of organic load and the PHAs yields. The highest removal of organic load achieved after 48 h of aerobic treatment was 84.0 ± 0.9 %, whereas the maximum PHAs yield was 21.46 ± 0.13 kg PHAs/m3 initial CIW. • The simultaneous treatment and valorization of confectionary wastewater was assessed via an anaerobic-aerobic process. • The operational optimization of the anaerobic stage and the biocatalysts of the aerobic stage are equally important. • The hydrogen yields and distribution of the metabolites are mainly affected by the feeding strategy. • Up to 12.70 ± 0.35 m3 H 2 /m3 initial wastewater and 21.46 ± 0.13 kg PHAs/m3 initial wastewater were produced. • Efficient reduction up to ∼90% of its organic load was achieved by the two stage process. [ABSTRACT FROM AUTHOR]

A combined Lewis-Brønsted acid ethanolysis of sugars was thoroughly investigated with the aim of producing ethyl levulinate (EL) in a single step. Ethanolysis carried out at 453 K for 4 h using H 2 SO 4 (1 wt%) and AlCl 3 ·6H 2 O (30 mol % with respect to sugars) produced a yield of 60 mol % of EL respect to glucose and starch. Such optimised conditions were positively applied directly on different food waste, preliminarily characterised and found to be mainly composed by simple (10–15%) and relatively complex sugars (20–60%), besides proteins (6–10%) and lipids (4–10%), even in their wet form. The catalytic system resulted robust enough to the point that the copresence of proteins, lignin, lipids and mineral salts not only did not negatively affect the overall reactivity, but resulted efficiently converted into soluble species, and specifically, into other liquid biofuels of different nature. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the influence of the hydraulic retention time (HRT) and the pH on the fermentative hydrogen production from a food industry waste (FIW), in a continuous stirred tank bioreactor. Thus, hydrogen production was investigated for HRTs of 12, 8, 6 and 4 h and the results showed a long and stable reactor operation with high hydrogen content in the gas phase and high hydrogen production rates. The optimal HRT was found to be in the range between 6 and 12 h, corresponding to hydrogen yields of 96.27 ± 3.36 and 101.75 ± 3.71 L H 2 /kg FIW for 12 and 6 h, respectively. In the sequel, the effect of the pH (in the range 5–5.9) was investigated, by changing the buffer solution (BS) components, while the HRT value was maintained at 12 h. As anticipated, the results showed that the operating pH had a significant influence on hydrogen production rates and yields. Characterization of the microbial community was performed at various pH values, giving thus a deeper insight to the well-established hydrogen production process from FIW, since the possible biochemical pathways followed by the microbial consortium, under different operational conditions were elucidated. [ABSTRACT FROM AUTHOR]

In this study a novel modeling approach for describing fermentative hydrogen production in a continuous stirred tank reactor (CSTR) was developed, using the Aquasim modeling platform. This model accounts for the key metabolic reactions taking place in a fermentative hydrogen producing reactor, using fixed stoichiometry but different reaction rates. Biomass yields are determined based on bioenergetics. The model is capable of describing very well the variation in the distribution of metabolic products for a wide range of hydraulic retention times (HRT). The modeling approach is demonstrated using the experimental data obtained from a CSTR, fed with food industry waste (FIW), operating at different HRTs. The kinetic parameters were estimated through fitting to the experimental results. Hydrogen and total biogas production rates were predicted very well by the model, validating the basic assumptions regarding the implicated stoichiometric biochemical reactions and their kinetic rates. [ABSTRACT FROM AUTHOR]

In this study fungal pretreatment of willow sawdust (WSD) via the white rot fungi Leiotrametes menziesii and Abortiporus biennis was studied and the effect on fractionation of lignocellulosic biomass and biochemical methane potential (BMP), was evaluated. Scanning electron microscopy (SEM) and IR spectroscopy were used to investigate the changes in the structural characteristics of the pretreated WSD. Fungal pretreatment results revealed that A. biennis is more attractive, since it resulted in higher lignin degradation and lower holocellulose uptake. Samples of the 14th and 30th d of cultivation (i.e. the middle and the end of the pretreatment experiment) with both fungi were used for BMP tests and the effect of pretreatment duration was also evaluated. BMP increase by 31 and 43% was obtained due to the cultivation of WSD with A. biennis , for 14 and 30 d, respectively. In addition, combination of biological (after 30 d of cultivation) with alkaline (NaOH 20 g/100 gTS) pretreatment was performed, in order to assess the effect of the chemical agent on biologically pretreated WSD, in terms of lignocellulosic content and BMP. Combination of alkaline with fungal pretreatment led to high lignin degradation for both fungi, while the cellulose and hemicellulose removal efficiencies were higher for combined alkaline and L. menziesii pretreatment. The maximum BMP was observed for the combined alkaline and A. biennis pretreatment and was 12.5 and 50.1% higher than the respective alkaline and fungal pretreatment alone and 115% higher than the respective BMP of raw WSD. [ABSTRACT FROM AUTHOR]

Platinum complexes with a methoxy-amino phosphine or an ethylene-linked nitrogen-containing bis(phosphine) ligand have been synthesized and fully characterized by spectroscopic as well as crystallographic studies. The first ligand is bound to the metal in a P , N -bidentate coordination mode and with cis geometry, independently of the reaction temperature. Synthesis of a platinum complex with the second ligand at room temperature, afforded a mixture comprising 86% of a neutral cis complex, in which the ligand is bound to the metal only via the two P-donors, and 14% of a P , N , P -terdentate ionic complex where the two P atoms are trans to each other. On the other hand, synthesis of the complex at 100 °C, led almost exclusively to the formation of the cis -Pt complex in a P , P -bidentate coordination mode. The complexes were tested as catalysts without any promoting additive for the hydrogenation of trans -cinnamaldehyde under mild reaction conditions and displayed selectivity for the formation of cinnamyl alcohol of up to 67%. [ABSTRACT FROM AUTHOR]

In the present study the whole slurry obtained after different pretreatment methods applied on sunflower straw (SS) biomass, was used for biological production of hydrogen (BHP) and ethanol (BEP). BHP from pretreated SS was studied in batch experiments using mixed anaerobic sludge, via simultaneous saccharification and fermentation (SSF), while for BEP, SSF was carried out using the xylose – fermenting yeast P ichia stipitis . The experimental results obtained showed that for BHP, alkaline pretreatment with 20 g NaOH/100 gTS was optimal, leading to the highest hydrogen yield of 155.3 ± 6.5 L/kg TS. This yield was 52.5 times higher than the respective of raw SS (2.9 ± 0.0 LH 2 /kgTS) without enzyme addition. Pretreatment with the same chemical loadings of HCl or H 2 SO 4 resulted in the lowest BHP yields, due to the generation of inhibitory compounds. Although pretreatment with 20 g H 2 SO 4 /100 gTS also caused inhibition of P. stipitis giving the lowest BEP yield, pretreatment with 20 g HCl/100 gTS led to the highest BEP yield of 104.78 ± 0.08 mg ethanol/gTS, indicating the varying sensitivity of different microbial species to the inhibitory compounds that are generated during pretreatment. [ABSTRACT FROM AUTHOR]

Cytosolic GIVA phospholipase A 2 (GIVA cPLA 2 ) initiates the eicosanoid pathway of inflammation and thus inhibitors of this enzyme constitute novel potential agents for the treatment of inflammatory diseases. Traditionally, GIVA cPLA 2 inhibitors have suffered systemically from high lipophilicity. We have developed a variety of long chain 2-oxoamides as inhibitors of GIVA PLA 2 . Among them, AX048 was found to produce a potent analgesic effect. We have now reduced the lipophilicity of AX048 by replacing the long aliphatic chain with a chain containing an ether linked aromatic ring with in vitro inhibitory activities similar to AX048. [ABSTRACT FROM AUTHOR]

When properly designed, pretreatments may enhance the methane potential and/or anaerobic digestion rate, improving digester performance. This paper aims at providing some guidelines on the most appropriate pretreatments for the main feedstocks of biogas plants. Waste activated sludge was firstly investigated and implemented at full-scale, its thermal pretreatment with steam explosion being most recommended as it increases the methane potential and digestion rate, ensures sludge sanitation and the heat needed is produced on-site. Regarding fatty residues, saponification is preferred for enhancing their solubilisation and bioavailability. In the case of animal by-products, this pretreatment can be optimised to ensure sterilisation, solubilisation and to reduce inhibition linked to long chain fatty acids. With regards to lignocellulosic biomass, the first goal should be delignification, followed by hemicellulose and cellulose hydrolysis, alkali or biological (fungi) pretreatments being most promising. As far as microalgae are concerned, thermal pretreatment seems the most promising technique so far. [ABSTRACT FROM AUTHOR]

Dark fermentation (DF) of several types of wastes is a promising process to alleviate environmental pollution as it leads to the production of valuable hydrogen (H 2) gas and high added value products, such as volatile fatty acids (VFAs). In this study a kinetic model for fermentative H 2 production in an Up-flow column reactor (UFCR) is presented. Τhe model structure includes seven biochemical reactions taking place in a two-phase biofilm-liquid system. The observed difference in the overall stoichiometry of the bioconversion process for different hydraulic retention times (HRTs) is predicted by this model as it is attributed to the difference in the extent of individual bioconversion steps, each of which has a constant stoichiometry but a different rate depending on the HRT. The respective kinetic parameters were estimated through model fitting to the experimental results of the UFCR, which operated at different HRTs (12–2 h) and fed with the soluble fraction of a food industry waste (FIW). A good agreement of the experimental and predicted values of soluble metabolic products and H 2 production was obtained, rendering this model as a useful tool for further investigation and prediction of the characteristics of the DF process in attached-biomass growth systems. The reactions which are considered in the model. [Display omitted] • The model describes H 2 production in attached-biomass growth systems. • 7 reactions take place using fixed stoichiometry and different reaction kinetics. • H 2 production is correlated with butyrate production. • H 2 production may be increased if homoacetogenesis is suppressed. [ABSTRACT FROM AUTHOR]

The effect of different pretreatment approaches based on alkali (NaOH)/hydrogen peroxide (H2O2) on willow sawdust (WS) biomass, in terms of delignification efficiency, structural changes of lignocellulose and subsequent fermentation toward ethanol, was investigated. Bioethanol production was carried out using the conventional yeast Saccharomyces cerevisiae, as well as three non-conventional yeasts strains, i.e., Pichia stipitis, Pachysolen tannophilus, Wickerhamomyces anomalus X19, separately and in co-cultures. The experimental results showed that a two-stage pretreatment approach (NaOH (0.5% w/v) for 24 h and H2O2 (0.5% v/v) for 24 h) led to higher delignification (38.3 ± 0.1%) and saccharification efficiency (31.7 ± 0.3%) and higher ethanol concentration and yield. Monocultures of S. cerevisiae or W. anomalus X19 and co-cultures with P. stipitis exhibited ethanol yields in the range of 11.67 ± 0.21 to 13.81 ± 0.20 g/100 g total solids (TS). When WS was subjected to H2O2 (0.5% v/v) alone for 24 h, the lowest ethanol yields were observed for all yeast strains, due to the minor impact of this treatment on the main chemical and structural WS characteristics. In order to decide which is the best pretreatment approach, a detailed techno-economical assessment is needed, which will take into account the ethanol yields and the minimum processing cost. [ABSTRACT FROM AUTHOR]

Data for the quantity of greywater produced in Greek households was collected from two different cities, while samples from different residences were taken for greywater's quality characterization. Laboratory experiments were also performed to investigate the use of coagulation on COD and TSS removal from two different types of greywater, while a combined treatment consisting of coagulation, sand filtration and adsorption on granular activated carbon (GAC) was applied to achieve adequate quality for greywater reuse. According to the results, average greywater production in Greek residences was 82.6±49.3L per inhabitant and day, while the major sources were shower/bathtub and laundry, contributing to 41% and 26%, respectively. On the other hand, blackwater production was estimated at 59.4±29.6L per inhabitant and day. Greywater produced in shower/bathtub and hand basin had similar quality characteristics, while kitchen sink's greywater were more contaminated, presenting lower pH values and higher concentrations of TSS and total COD. Coagulation experiments with FeCl3 and Al2(SO4)3 showed that process efficiency was differentiated significantly according to the type of greywater and the coagulant used. The highest removal efficiency (COD: 81%; TSS: 79%) was achieved for greywater that did not contain wastewater from the laundry and for Al2(SO4)3 ×14 H2O dosage of 800mgL−1. The application of coagulation, sand filtration and GAC adsorption resulted to average concentrations of COD and TSS equal to 28±11 and 11±3mgL−1, respectively, in treated greywater. [ABSTRACT FROM AUTHOR]

Abstract: Electricity production from filter sterilized cheese whey at different organic loads (0.35, 0.7, 1.5, 2.7 and 6.7gCOD/L respectively) was investigated in a two-chamber microbial fuel cell (MFC). The best performance of the cell was observed at the highest concentration of the pretreated (filter sterilized) cheese whey (6.7gCOD/L) corresponding to a maximum power density of approximately 46mW/m2. Experiments using glucose (0.35gCOD/L) were also performed for comparison reasons. The study of the open-circuit impedance characteristics of the MFC and of the individual electrodes revealed that the open-circuit impedance of the MFC depended to practically the same extent on both the ohmic resistance between the anode and cathode and the overall polarization resistance. The polarization resistance of the MFC decreased significantly under closed-circuit conditions, which in turn implies that the ohmic overpotential is the main contribution to the energy losses in two-chamber MFCs. [Copyright &y& Elsevier]

Phospholipases A2 (PLA2s) are enzymes that are capable of catalyzing the hydrolysis of the sn-2 ester bond of glycerophospholipids, releasing free fatty acids, including arachidonic acid (AA), and lysophospholipids. Both products are precursor signaling molecules involved in inflammation. Among the various PLA2s, cytosolic GIVA cPLA2 is considered a major target for inflammatory diseases, while secreted GIIA sPLA2 is involved in cardiovascular diseases. We have developed lipophilic 2-oxoamides based on (S)-γ- or δ-amino acids as potent and selective inhibitors of GIVA cPLA2, which present interesting in vivo anti-inflammatory activity. 2-Oxoamides based on natural α-amino acids are selective inhibitors of GIIA sPLA2. The mode of binding of 2-oxoamides with either GIVA cPLA2 or GIIA sPLA2 has been studied by various techniques. [ABSTRACT FROM AUTHOR]

Abstract: The present study focused on the application of the Anaerobic Digestion Model 1 on the methane production from acidified sorghum extract generated from a hydrogen producing bioreactor in a two-stage anaerobic process. The kinetic parameters for hydrogen and volatile fatty acids consumption were estimated through fitting of the model equations to the data obtained from batch experiments. The simulation of the continuous reactor performance at all HRTs tested (20, 15, and 10d) was very satisfactory. Specifically, the largest deviation of the theoretical predictions against the experimental data was 12% for the methane production rate at the HRT of 20d while the deviation values for the 15 and 10d HRT were 1.9% and 1.1%, respectively. The model predictions regarding pH, methane percentage in the gas phase and COD removal were in very good agreement with the experimental data with a deviation less than 5% for all steady states. Therefore, the ADM1 is a valuable tool for process design in the case of a two-stage anaerobic process as well. [Copyright &y& Elsevier]

Abstract: The Anaerobic digestion model 1 (ADM1) framework can be used to predict fermentative hydrogen production, since the latter is directly related to the acidogenic stage of the anaerobic digestion process. In this study, the ADM1 model framework was used to simulate and predict the process of fermentative hydrogen production from the extractable sugars of sweet sorghum biomass. Kinetic parameters for sugars’ consumption and yield coefficients of acetic, propionic and butyric acid production were estimated using the experimental data obtained from the steady states of a CSTR. Batch experiments were used for kinetic parameter validation. Since the ADM1 does not account for metabolic products such as lactic acid and ethanol that are crucial during the fermentative hydrogen production process, the structure of the model was modified to include lactate and ethanol among the metabolites and to improve the predictions. The modified ADM1 simulated satisfactorily batch experiments although further modifications could be made in order to further improve the predictions for the hydrogenogenic process. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to assess the influence of substrate concentration on the fermentative hydrogen production from sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time (HRT) of 12 h and carbohydrate concentrations ranging from 9.89 to 20.99 g/L, in glucose equivalents. The maximum hydrogen production rate and yield were obtained at the concentration of 17.50 g carbohydrates/L and were 2.93 ± 0.09 L H2/L reactor/d and 0.74 ± 0.02 mol H2/mol glucose consumed, corresponding to 8.81 ± 0.02 L H2/kg sweet sorghum, respectively. The main metabolic product at all steady states was butyric acid, while ethanol production was high at high substrate concentrations. The experiments showed that hydrogen productivity depends significantly on the initial carbohydrate concentration, which also influences the distribution of the metabolic products. [Copyright &y& Elsevier]

Abstract: In this study, the possibility of electricity generation from diluted cheese whey in a two-chamber mediator-less microbial fuel cell (MFC) was investigated. Synthetic substrates such as glucose and lactose were also used for characterization of the MFC and for microbial acclimation at the anode compartment. The maximum power density obtained using diluted cheese whey was 18.4mW/m2 (normalized to the geometric area of the anodic electrode, which was 13.8cm2), corresponding to a current density of 80mA/m2 and a MFC voltage of 0.23V. The coulombic efficiency ɛ cb was very low (only 1.9%), implying that a pretreatment step of raw cheese whey is essential prior to use. For comparison, in the case of sugars (glucose and lactose) the obtained maximum power density was 15.2mW/m2 with ɛ cb equal to 28% for glucose and 17.2mW/m2 with ɛ cb equal to 22% for lactose. Impedance spectroscopy measurements showed that the dominant contribution to the cell overpotential was due to the ohmic resistance of the MFC. The contribution of the electrode overpotentials was also significant, mainly that of the cathode overpotential. [Copyright &y& Elsevier]

Abstract: The present study focused on the influence of pH on the fermentative hydrogen production from the sugars of sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time of 12 h and a pH range of 3.5–6.5. The maximum hydrogen production rate and yield were obtained at pH 5.3 and were 1752 ± 54 mL H2/d or 3.50 ± 0.07 L H2/L reactor/d and 0.93 ± 0.03 mol H2/mol glucose consumed or 10.51 L H2/kg sweet sorghum, respectively. The main metabolic product at this pH value was butyric acid. The hydrogen productivity and yield were still at high levels for the pH range of 5.3–4.7, suggesting a pH value of 4.7 as optimum for hydrogen production from an economical point of view, since the energy demand for chemicals is lower at this pH. At this pH range, the dominant fermentation product was butyric acid but when the pH culture sharply decreased to 3.5, hydrogen evolution ceased and the dominant metabolic products were lactic acid and ethanol. [Copyright &y& Elsevier]

This study focuses on the exploitation of cheese whey as a source for hydrogen and methane, in a two-stage continuous process. Mesophilic fermentative hydrogen production from undiluted cheese whey was investigated at a hydraulic retention time (HRT) of 24h. Alkalinity addition (NaHCO3) or an automatic pH controller were used, to maintain the pH culture at a constant value of 5.2. The hydrogen production rate was 2.9±0.2L/Lreactor/d, while the yield of hydrogen produced was approximately 0.78±0.05mol H2/mol glucose consumed, with alkalinity addition, while the respective values when using pH control were 1.9±0.1L/Lreactor/d and 0.61±0.04mol H2/mol glucose consumed. The corresponding yields of hydrogen produced were 2.9L of H2/L cheese whey and 1.9L of H2/L cheese whey, respectively. The effluent from the hydrogenogenic reactor was further digested to biogas in a continuous mesophilic anaerobic bioreactor. The anaerobic digester was operated at an HRT of 20d and produced approximately 1L CH4/d, corresponding to a yield of 6.7L CH4/L of influent. The chemical oxygen demand (COD) elimination reached 95.3% demonstrating that cheese whey could be efficiently used for hydrogen and methane production, in a two-stage process. [Copyright &y& Elsevier]

Abstract: A variety of 2-oxoamides and related amides based on natural and non-natural amino acids were synthesized. Their activity on two human intracellular phospholipases (GIVA cPLA2 and GVIA iPLA2) and one human secretory phospholipase (GV sPLA2) was evaluated. We show that an amide based on (R)-γ-norleucine is a highly selective inhibitor of GV sPLA2. [Copyright &y& Elsevier]

Abstract: The present study focuses on the exploitation of sweet sorghum biomass as a source for hydrogen and methane. Fermentative hydrogen production from the sugars of sweet sorghum extract was investigated at different hydraulic retention times (HRT). The subsequent methane production from the effluent of the hydrogenogenic process and the methane potential of the remaining solids after the extraction process were assessed as well. The highest hydrogen production rate (2550ml H2/d) was obtained at the HRT of 6h while the highest yield of hydrogen produced per kg of sorghum biomass was achieved at the HRT of 12h (10.4l H2/kg sweet sorghum). It has been proved that the effluent from the hydrogenogenic reactor is an ideal substrate for methane production with approximately 29l CH4/kg of sweet sorghum. Anaerobic digestion of the solid residues after the extraction process yielded 78l CH4/kg of sweet sorghum. This work demonstrated that biohydrogen production can be very efficiently coupled with a subsequent step of methane production and that sweet sorghum could be an ideal substrate for a combined gaseous biofuels production. [Copyright &y& Elsevier]

In the present study the bioconversion of dried household food waste (FORBI) to energy carriers was investigated aiming to its sustainable management and valorization. FORBI was either directly fermented towards ethanol and hydrogen or was previously subjected to extraction with water resulting to a liquid fraction (extract) rich in sugars and a solid residue, which were then fermented separately. Subsequently, the effluents were assessed as substrates for methane production via anaerobic digestion (AD). Mono-cultures and co-cultures of C5 and C6 yeasts were used for the alcoholic fermentation whereas for the production of hydrogen, mixed acidogenic consortia were used. Taking into account the optimum yields of biofuels, the amount of recoverable energy was estimated based for each different approach. The maximum ethanol yield was 0.16 g ethanol per kg of FORBI and it was achieved for separate fermentation of liquid and solid fractions of the waste. The highest hydrogen yield that was observed was 210.44 L ± 4.02 H 2 /kg TS FORBI for 1% solids loading and supplementation with cellulolytic enzymes. Direct AD of either the whole FORBI or its individual fractions led to lower overall energy recovery, compared to that obtained when fermentation and subsequent AD were applied. The recoverable energy was estimated for the different exploitation approaches of the waste. The maximum achieved recoverable energy was 21.49 ± 0.57 MJ/kg. Unlabelled Image • FORBI (food waste) was bio converted to H 2 , ethanol and methane in 2 stage systems. • Water extraction for separate fermentation of sugars/solids enhanced ethanol yield. • Extraction process did not affect final hydrogen yields. • Energy gain was higher from 2 stage approach than direct AD of FORBI or fractions. [ABSTRACT FROM AUTHOR]

The effect of thermal, acid and alkali pretreatment methods on biological hydrogen (BHP) and bioethanol production (BP) from grass lawn (GL) waste was investigated, under different process schemes. BHP from the whole pretreatment slurry of GL was performed through mixed microbial cultures in simultaneous saccharification and fermentation (SSF) mode, while BP was carried out through the C5yeast Pichia stipitis, in SSF mode. From these experiments, the best pretreatment conditions were determined and the efficiencies for each process were assessed and compared, when using either the whole pretreatment slurry or the separated fractions (solid and liquid), the separate hydrolysis and fermentation (SHF) or SSF mode, and especially for BP, the use of other yeasts such as Pachysolen tannophilus or Saccharomyces cerevisiae. The experimental results showed that pretreatment with 10 gH2SO4/100 g total solids (TS) was the optimum for both BHP and BP. Separation of solid and liquid pretreated fractions led to the highest BHP (270.1 mL H2/g TS, corresponding to 3.4 MJ/kg TS) and also BP (108.8 mg ethanol/g TS, corresponding to 2.9 MJ/kg TS) yields. The latter was achieved by using P. stipitis for the fermentation of the hydrolysate and S. serevisiae for the solid fraction fermentation, at SSF. [ABSTRACT FROM AUTHOR]

Various pretreatment methods, such as thermal, alkaline and acid, were applied on grass lawn (GL) waste and the effect of each pretreatment method on the Biochemical Methane Potential was evaluated for two options, namely using the whole slurry resulting from pretreatment or the separate solid and liquid fractions obtained. In addition, the effect of each pretreatment on carbohydrate solubilization and lignocellulossic content fractionation (to cellulose, hemicellulose, lignin) was also evaluated. The experimental results showed that the methane yield was enhanced with alkaline pretreatment and, the higher the NaOH concentration (20 g/100 gTotal Solids (TS)), the higher was the methane yield observed (427.07 L CH4/kg Volatile Solids (VS), which was almost 25.7% higher than the BMP of the untreated GL). Comparing the BMP obtained under the two options, i.e., that of the whole pretreatment slurry with the sum of the BMPs of both fractions, it was found that direct anaerobic digestion without separation of the pretreated biomass was favored, in almost all cases. A preliminary energy balance and economic assessment indicated that the process could be sustainable, leading to a positive net heat energy only when using a more concentrated pretreated slurry (i.e., 20% organic loading), or when applying NaOH pretreatment at a lower chemical loading. [ABSTRACT FROM AUTHOR]

• The potential use of potato peels waste for bioethanol production was tested. • A newly isolated strain of W. anomalus was used for ethanol production. • Different methods were tested for saccharification. • The possibility of using lab-scale produced enzymes was also explored. • Different process schemes were evaluated for fermentation. The present study focuses on the exploration of the potential use of potato peels waste (PPW) as feedstock for bioethanol production, using a newly isolated yeast strain, Wickerhamomyces anomalus, via different saccharification and fermentation schemes. The saccharification of PPW was performed via thermal and chemical (acid, alkali) pretreatment, as well as via enzymatic hydrolysis through the use of commercial enzymes (cellulase and amylase) or enzymes produced at lab scale (alpha-amylase from Bacillus sp. Gb67), either separately or in mixtures. The results indicated that the enzymatic treatment by commercial enzymes led to a higher saccharification efficiency (72.38%) and ethanol yield (0.49 g/g consumed sugars) corresponding to 96% of the maximum theoretical. In addition, acid pretreatment was found to be beneficial for the process, leading also to high hydrolysis and ethanol yields, indicating that PPW is a very promising feedstock for bio-ethanol production by W. anomalus under different process schemes. [ABSTRACT FROM AUTHOR]

In the present study the non-conventional yeast Wickerhamomyces anomalus X19, was evaluated as biocatalyst for direct, low cost bioethanol production, using natural date palm sap (DPS) as substrate. Initial experiments were conducted with synthetic media in order to characterize the strain in terms of its nitrogen requirements, the effect of initial substrate concentration on the ethanol yields and the main kinetic constants during alcoholic fermentation. Subsequently, the effect of aerobic or anaerobic conditions was assessed with DPS as substrate, in batch mode and the possible improvement of ethanol yields was further investigated via fed batch experiments. It was shown that W. anomalus X19 was not inhibited by low pH (<3) and high initial sugar concentrations (up to 160 g/L), leading in all cases to ethanol yields that exceeded 80% of the theoretically estimated values. The highest ethanol concentration from DPS fermentation was achieved in fed batch experiments, reaching 73.11 g/L and the ethanol yield was 0.46 g/g sugars, which corresponded to more than 90% of the theoretical maximum. • Date palm sap was assessed as renewable EtOH production feedstock via W. anomalus. • Batch and fed batch fermentations reached to high yields without pH adjustment. • EtOH max at fed-batch mode exceeded 73 g/L leading to 91% fermentation efficiency. [ABSTRACT FROM AUTHOR]

The treatment and biotechnological exploitation of expired fruit juices (EFJ) towards biohydrogen, polyhydroxyalkanoates (PHAs) and lipids production was investigated. The EFJ were initially fermented via an acidogenic consortium, during which the effect of the organic loading rate (OLR, 20–40 g sugars/L.d) on the sugars uptake and the yields of metabolites i.e. hydrogen, volatile fatty acids (VFAs) and lactate, was studied. The increase of the OLR resulted to lower bioconversion of sugars and metabolic shift to lactate production, whereas the highest hydrogen yield, 10.83 ± 0.41 L H 2 /m3 EFJ, was obtained for the OLR 30 g sugars/L.d. The acidogenic effluents were then utilized for the production of PHAs and microbial lipids, via bacterial heterotrophic and cyanobacterial consortia, respectively. The PHAs produced were in all cases copolymers, and the highest yield, 20.69 ± 1.01 kg PHAs/m3 EFJ was achieved from the effluent with the highest VFAs content. Microbial lipids were also successfully produced from all effluents. The results revealed that low VFAs and high sugars concentration, allowed cyanobacterial growth of up to 373.5 mg /L.d and maximum lipid content of up to 11.7 % d.w. (5.47 ± 0.49 kg biolipids/m3 EFJ), as well as significant substrate degradation (dissolved oxygen demand - d-COD, total nitrogen-ΤΝ, orthophosphates-PO 4 3-, total sugars up to about 93 %, 95 %, 67 % and 96 %, respectively). • The simultaneous treatment and valorization of expired fruit juices (EFJ) was investigated. • The organic loading during continuous dark fermentation of EFJ affected products' yields. • Effluents with high amount of volatile fatty acids yielded to high PHAs. • Effluents with high amount of residual sugars yielded to high microbial lipids. • The utilization strategy of the effluents may vary based on their composition. [ABSTRACT FROM AUTHOR]

Review: 147 refs. [ABSTRACT FROM AUTHOR]

As an easily obtained organic waste, by-product acetic acid could be an appropriate co-substrate with blue algae wastes (increase C/N ratio of substrates) for co-fermentation of PHA production. However, there are still acrylic acid and other chemicals in by-product acetic acid, which could cause severe inhibition for fermenting microorganisms during PHA production process. The current study represented that alkali pretreatment (pH level of 12) is a more favorable method compared with thermal pretreatment (80 ℃ for 30 min) for breaking cell walls of blue algae. It seemed that there was no synergistic effect of the combination of thermal and alkali pretreatment methods (temperature of 80 ℃ and pH level of 12). Optimal parameters during electro-fenton process for removal of inhibitors in by-product acetic acid were under current of 0.5 A, pH level of 3 and reaction time of 120 min. Both the highest dry weight of PHA and PHA concentration were achieved by applying blue algae and by-product acetic acid (after pretreatment) as co-substrates (mixed ratio of 3:1, stirring speed of 200 r/min, 24 h), indicating that using by-product acetic acid (after pretreatment) as co-substrate could increase C/N ratio and promote PHA production successfully. The current study could offer new insights for improving PHA production by co-fermentation. [Display omitted] • Alkali pretreatment is a more favorable method compared with thermal pretreatment. • There was no synergistic effect of the combination of thermal and alkali pretreatment. • Optimal parameters for removal of inhibitors in by-product acetic acid were determined. • By-product acetic acid (after pretreatment) as co-substrate could promote PHA production. [ABSTRACT FROM AUTHOR]

Abstract: An aniline- and two pyridine-derived (R)-BINOL-based P,N-containing phosphite ligands have been synthesized via a one-pot procedure. Treatment of the aniline-derived ligand with 1equiv of [Rh(COD)2]BF4 yielded a mixture of a P,N-chelate complex and a biligated P-monodentate complex (exclusively obtained by treatment of the ligand with rhodium in a ratio of 2:1), while the pyridine analogues led to the corresponding P,N-bidentate complexes as unique species. For the first time, such phosphites were studied for rhodium-catalyzed enantioselective olefin hydrogenation. At room temperature, the aniline-derived ligand was found to be more active and selective compared to the pyridine analogues, which can probably be attributed to its different coordination mode and the formation of a biligated P-monodentate complex. [Copyright &y& Elsevier]

The biotransformation of the pre-dried and shredded organic fraction of kitchen waste to ethanol was investigated, via co-cultures of the yeasts Saccharomyces cerevisiae and Pichia stipitis (Scheffersomyces stipitis ). Preliminary experiments with synthetic media were performed, in order to investigate the effect of different operational parameters on the ethanol production efficiency of the co-culture. The control of the pH and the supplementation with organic nitrogen were shown to be key factors for the optimization of the process. Subsequently, the ethanol production efficiency from the waste was assessed via simultaneous saccharification and fermentation experiments. Different loadings of cellulolytic enzymes and mixtures of cellulolytic with amylolytic enzymatic blends were tested in order to enhance the substrate conversion efficiency. It was further shown that for solids loading up to 40% waste on dry mass basis, corresponding to 170 g.L −1 initial concentration of carbohydrates, no substrate inhibition occurred, and ethanol concentration up to 45 g.L −1 was achieved. [ABSTRACT FROM AUTHOR]

PHAs are a form of cellular storage polymers with diverse structural and material properties, and their biodegradable and renewable nature makes them a potential green alternative to fossil fuel-based plastics. PHAs are obtained through extraction via various mechanical, physical and chemical processes after their intracellular synthesis. Most studies have until now focused on pure cultures, while information on mixed microbial cultures (MMC) remains limited. In this study, ultrasonic (US) disruption and alkaline digestion by NaOH were applied individually and in combination to obtain PHAs products from an acclimated MMC using phenol as the carbon source. Various parameters were tested, including ultrasonic sound energy density, NaOH concentration, treatment time and temperature, and biomass density. US alone caused limited cell lysis and resulted in high energy consumption and low efficiency. NaOH of 0.05–0.2 M was more efficient in cell disruption, but led to PHAs degradation under elevated temperature and prolonged treatment. Combining US and NaOH significantly improved the overall process efficiency, which could reduce energy consumption by 2/3rds with only minimal PHAs degradation. The most significant factor was identified to be NaOH dosage and treatment time, with US sound energy density playing a minor role. Under the semi-optimized condition (0.2 M NaOH, 1300 W L-1, 10 min), over 70% recovery and 80% purity were achieved from a 3 g L−1 MMC slurry of approximately 50% PHAs fraction. The material and thermal properties of the products were analyzed, and the polymers obtained from US + NaOH treatments showed comparable or higher molecular weight to previously reported results. The products also exhibited good thermal stability and rheological properties, compared to the commercial standard. In conclusion, the combined US and NaOH method has the potential in real application as an efficient process to obtain high quality PHAs from MMC, and cost-effectiveness can be further optimized. [Display omitted] • Ultrasonic (US) and alkaline digestion used to recover PHB from a mixed culture. • US disruption had limited effect of cell lysis and high energy consumption. • NaOH digestion was more efficient but led to PHA degradation under high temperature. • US + NaOH showed synergetic effect, reduced treatment time and energy consumption. • US + NaOH can be cost-effective after optimization, showing potential of scaling-up. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the effect of anode materials, namely a carbon nanotube (CNT)-buckypaper and a commercial carbon paper (CP) on the performance of a two-chamber microbial electrolysis cell (MEC), in terms of hydrogen production and main electrochemical characteristics. The experiments were performed using both acetate-based synthetic wastewater and real wastewater, specifically the effluent of a dark fermentative hydrogenogenic reactor (fermentation effluent), using cheese whey (CW) as substrate. The results showed that CP led to higher hydrogen production efficiency and current density compared to the CNT-buckypaper anode, which was attributed to the better colonization of the CP electrode with electroactive microorganisms, due to the negative effects of CNT-based materials on the bacteria metabolism. By using the fermentation effluent as substrate, a two-stage process is developed, where dark fermentation (DF) of CW for hydrogen production occurs in the first step, while the DF effluent is used as substrate in the MEC, in the second step, to further increase hydrogen production. By coupling DF-MEC, a dual environmental benefit is provided, combining sustainable bioenergy generation together with wastewater treatment, a fact that is also reinforced by the toxicity data of the current study. [ABSTRACT FROM AUTHOR]

[Display omitted] • Simultaneous ammonia mitigation and biogas upgrading using an integrated BES was accomplished. • Ammonia utilization and hydrogen production reached 73.67% and 202.87 mL under an applied voltage 0.4 V. • The highest methane production and content were attained with in situ H 2 injection at the beginning. • Both microbial communities and enzymatic abundances related to methanogenesis were amplified. Biohydrogen using migrated ammonia as nitrogen source, and biogas upgrading with hydrogen collected at biocathode in an integrated bioelectrochemical system (BES) were investigated, during the anaerobic digestion of Taihu blue algae. Under an applied voltage of 0.4 V, biohydrogen (202.87 mL) reached 2.34 and 2.90 times than groups with applied voltage of 0 V and 0.8 V, respectively. Moreover, biohydrogen of the group with 1000 mg/L initial ammonia addition (524.16 mL) reached 1.53 times than that the of the control. With 0.25 bar of H 2 injected at the beginning (R1), highest methane production (286.62) mL and content (75.73%) were obtained. Comparing to other groups, not only microbial genus responsible for both aceticlastic and hydrogenotrophic methanogens of the group R1 were apparently enriched, but key enzymes related to methane production also acquired better abundances. Therefore, it's promising to conduct the ammonia alleviating, hydrogen producing and biogas upgrading simultaneously using BES. [ABSTRACT FROM AUTHOR]

(R)-BINOL-derived bidentate P,N-phosphite ligands are prepared and tested in the hydrogenation of several prochiral olefins. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) results in permanent loss of motor functions. A significant aspect of the tissue damage and functional loss may be preventable as it occurs, secondary to the trauma. We show that the phospholipase A2 (PLA2) superfamily plays important roles in SCI. PLA2 enzymes hydrolyze membrane glycerophospholipids to yield a free fatty acid and lysophospholipid. Some free fatty acids (arachidonic acid) give rise to eicosanoids that promote inflammation, while some lysophospholipids (lysophosphatidylcholine) cause demyelination. We show in a mouse model of SCI that two cytosolic forms [calcium-dependent PLA2 group IVA (cPLA2 GIVA) and calcium-independent PLA2 group VIA (iPLA2s GVIA)], and a secreted form [secreted PLA2 group IIA (sPLA2 GIIA)] are up-regulated. Using selective inhibitors and null mice, we show that these PLA2s play differing roles, cPLA2 GIVA mediates protection, whereas sPLA2 GIIA and, to a lesser extent, iPLA22 GVIA are detrimental. Furthermore, completely blocking all three PLA2s worsens outcome, while the most beneficial effects are seen by partial inhibition of all three. The partial inhibitor enhances expression of cPLA9 and mediates its beneficial effects via the prostaglandin EP1 receptor. These findings indicate that drugs that inhibit detrimental forms of PLA2 (sPLA2 and iPLA2) and upregulate the protective form (cPLA2) may be useful for the treatment of SCI. [ABSTRACT FROM AUTHOR]

Wet explosion pretreatment of hybrid poplar sawdust (PSD) for the production of fermentable sugar was carried out in the pilot-scale. The effects of pretreatment conditions, such as temperature (170–190 °C), oxygen dosage (0.5–7.5% of dry matter (DM), w/w), residence time (10–30 min), on cellulose and hemicellulose digestibility after enzymatic hydrolysis were ascertained with a central composite design of the experiment. Further, enzymatic hydrolysis was optimized in terms of temperature, pH, and a mixture of CTec2 and HTec2 enzymes (Novozymes). Predictive modeling showed that cellulose and hemicellulose digestibility of 75.1% and 83.1%, respectively, could be achieved with a pretreatment at 177 °C with 7.5% O2 and a retention time of 30 min. An increased cellulose digestibility of 87.1% ± 0.1 could be achieved by pretreating at 190 °C; however, the hemicellulose yield would be significantly reduced. It was evident that more severe conditions were required for maximal cellulose digestibility than that of hemicellulose digestibility and that an optimal sugar yield demanded a set of conditions, which overall resulted in the maximum sugar yield. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD), being the most effective treatment method of waste activated sludge (WAS), allows for safe disposal. The present study deals with the electro-Fenton (EF) pretreatment for enhancing the WAS biogas potential with low-cost iron electrodes. The effect of pretreatment on the physicochemical characteristics of sludge was assessed. Following EF pretreatment, the pH, conductivity, soluble chemical oxygen demand (SCOD), and volatile fatty acids (VFA) increased to 7.5, 13.72 mS/cm, 4.1 g/L, and 925 mg/L, respectively. Capillary suction time (CST) analysis highlighted the dewaterability effect of EF on WAS, as demonstrated by the decrease in CST from 429 to 180 s following 30 min of pretreatment. Batch digestion assays presented an increase in the biogas yield to 0.135 L/g volatile solids (VS) after 60 min of EF pretreatment in comparison to raw sludge (0.08 L/g VS). Production of biogas was also found to improve during semi-continuous fermentation of EF-pretreated sludge conducted in a lab-scale reactor. In comparison to raw sludge, EF-pretreated sludge produced the highest biogas yield (0.81 L biogas/g VS) with a high COD removal rate, reaching 96.6% at an organic loading rate (OLR) of 2.5 g VS/L. d. Results revealed that the EF process could be an effective WAS disintegration method with maximum recovery of bioenergy during AD. [ABSTRACT FROM AUTHOR]

Sunflower residues are considered a prominent renewable source for biogas production during anaerobic digestion (AD). However; the recalcitrant structure of this lignocellulosic substrate requires a pretreatment step for efficient biomass transformation and increased bioenergy output. The aim of the present study was to assess the effect of alkaline pretreatment of various parts of the sunflower residues (e.g., heads and stalks) on their methane yield. Experimental data showed that pretreatment at mild conditions (55 °C; 24 h; 4 g NaOH 100 g−1 total solids) caused an increase in the biochemical methane potential (BMP) of both heads and stalks of the sunflower residues as determined in batch tests. The highest methane production (268.35 ± 0.11 mL CH4 g−1 volatile solids) was achieved from the pretreated sunflower head residues. Thereafter; the effect of alkaline pretreatment of sunflower head residues was assessed in continuous mode; using continuous stirred-tank reactors (CSTRs) under two operational phases. During the first phase; the CSTRs were fed with the liquid fraction produced from the pretreatment of sunflower heads. During the second phase; the CSTRs were fed with the whole slurry resulting from the pretreatment of sunflower heads (i.e., both liquid and solid fractions). In both operating phases; it was observed that the alkaline pretreatment of the sunflower head residues had a negligible (phase I) or even a negative effect on biogas production; which was contradictory to the results of the BMP tests. It seems that; during alkaline pretreatment; this part of the sunflower residues (heads) may release inhibitory compounds; which induce a negative effect on biogas production in the long term (e.g., during continuously run digesters such as CSTR) but not in the short-term (e.g., batch tests) where the effect of the inoculum may not permit the inhibition to be established. [ABSTRACT FROM AUTHOR]

Straws are agricultural residues that can be used to produce biomethane by anaerobic digestion. The methane yield of rice straw is lower than other straws. Steam explosion was investigated as a pretreatment to increase methane production. Pretreatment conditions with varying reaction times (12–30 min) and maximum temperatures (162–240 °C) were applied. The pretreated material was characterized for its composition and thermal and morphological properties. When the steam explosion was performed with a moderate severity parameter of S0 = 4.1 min, the methane yield was increased by 32% compared to untreated rice straw. This study shows that a harsher pretreatment at S0 > 4.3 min causes a drastic reduction of methane yield because inert condensation products are formed from hemicelluloses. [ABSTRACT FROM AUTHOR]

Ionic liquids have been recognised as interesting solvents applicable in efficient lignocellulosic biomass valorisation, especially in biomass fractionation into individual polymeric components or direct hydrolysis of some biomass fractions. Considering the chemical character of ionic liquids, two different approaches paved the way for the fractionation of biomass. The first strategy integrated a pre-treatment, hydrolysis and conversion of biomass through the employment of hydrogen-bond acidic 1-ethyl-3-methyimidazolim hydrogen sulphate ionic liquid. The second strategy relied on the use of a three-step fractionation process with hydrogen-bond basic 1-ethyl-3-methylimidazolium acetate to produce high purity cellulose, hemicellulose and lignin fractions. The proposed approaches were scrutinised for wheat straw and eucalyptus residues. These different biomasses enabled an understanding that enzymatic hydrolysis yields are dependent on the crystallinity of the pre-treated biomass. The use of acetate based ionic liquid allowed crystalline cellulose I to change to cellulose II and consequently enhanced the glucan to glucose yield to 93.1 ± 4.1 mol% and 82.9 ± 1.2 mol% for wheat straw and eucalyptus, respectively. However, for hydrogen sulphate ionic liquid, the same enzymatic hydrolysis yields were 61.6 ± 0.2 mol% for wheat straw and only 7.9 ± 0.3 mol% for eucalyptus residues. These results demonstrate the importance of both ionic liquid character and biomass type for efficient biomass processing. [ABSTRACT FROM AUTHOR]