Ioanna Ntaikou
University of Patras, Civil Engineering, Faculty Member
- University of Patras, Biology, Graduate StudentUniversity of Patras, Chemical Engineering, Post-Docadd
The aim of the present study was to develop efficient MMCs via their acclimation to a mixture of volatile fatty acids, sugars, and lactate i.e. the acidogenic effluents of a hydrogen-generating bioreactor processing food wastes.... more
The aim of the present study was to develop efficient MMCs via their acclimation to a mixture of volatile fatty acids, sugars, and lactate i.e. the acidogenic effluents of a hydrogen-generating bioreactor processing food wastes. Acclimation was conducted under sequential carbon (C) and nitrogen (N) limitation in draw fill reactors with organic loading 3 g/L (in terms of the chemical oxygen demand (COD)) in the C phase and ammonium chloride as N source in the N phase. Two DFRs were operated simultaneously with different carbon-to-nitrogen ratios (C/N) i.e. 10 g COD/g N-NH4+ and 50 g COD/g N-NH4+ and differences in the operational efficiency and microbial structure were assessed. Subsequently, batch experiments were conducted with both of the acclimated MMCs and with different initial substrate concentrations (6 -24 g COD/L) and different C/N ratios (50-200 g COD/g N-NH4+). It was shown that the feeding strategy during acclimation resulted in the domination of different microbial gene...
An enriched culture of Polyhydroxyalkanoates (PHAs)-forming bacteria was developed using the liquid fraction (condensate) which is generated during drying and shredding of food waste. A mixed enriched culture was used for the production... more
An enriched culture of Polyhydroxyalkanoates (PHAs)-forming bacteria was developed using the liquid fraction (condensate) which is generated during drying and shredding of food waste. A mixed enriched culture was used for the production of PHAs, in two Draw-Fill Reactors (DFRs). The culture was developed using cyclic limitation by carbon and nitrogen. Urea was used as nitrogen source and a mixture of volatile fatty acids (VFAs), lactic acid, ethanol and glucose, simulating the composition of the condensate as carbon source. Two cycles of experiments were performed aiming to investigate the effect of the organic loading on the yields and composition of the produced PHAs. The results showed that the organic loading did not significantly affect the accumulation capacity of PHAs, with the average yield for DFR-1 being 16±5% g PHAs/g DCW (dry cell weight) and for DFR-2 19±3% g PHAs/g DCW. The HV:HB ratio in DFR-1 was estimated to be (19±4):(81±4), whereas in DFR-2 (26±2):(74±2) indicatin...
The accumulation potential of poly-hydroxyalkanoates (PHAs) produced from an acclimated mixed microbial culture (MMC) under different dissolve oxygen (DO) levels and pH was investigated, using volatile fatty acids (VFAs) as carbon source.... more
The accumulation potential of poly-hydroxyalkanoates (PHAs) produced from an acclimated mixed microbial culture (MMC) under different dissolve oxygen (DO) levels and pH was investigated, using volatile fatty acids (VFAs) as carbon source. Specifically, the PHAs production potential of the MMC was evaluated in batch mode in a 5L bioreactor under controlled high aeration (DO level set at 25% saturation, DO25) and low aeration (DO level set at 5% saturation, DO5). The effect of the controlled DO level on the PHAs yield expressed in % PHAs/DCW (w/w) and also the monomeric composition was evaluated in comparison to the results obtained during constant aeration at 2L/min/L rector i.e. with highly varying DO (DOv). The optimal yield of 79.5±0.14% PHAs/DCW was achieved for DO25, while in the cases of DO5 results were similar to those from DOv, i.e. 60 % PHAs/DCW and 65 % PHAs/DCW, respectively . In all cases, P(3HB-co-3HV) was produced whereas the assimilation of propionate to HV in the pol...
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BACKGROUNDFruit juices are an exceptional source of nutrients; however, due to their short shelf‐life and vulnerability to microbial degradation, large volumes of juice are regularly discarded worldwide. As a wastewater, discarded fruit... more
BACKGROUNDFruit juices are an exceptional source of nutrients; however, due to their short shelf‐life and vulnerability to microbial degradation, large volumes of juice are regularly discarded worldwide. As a wastewater, discarded fruit juices (DFJ) possess high organic loads with significant amounts of nitrogen and phosphorus, making them a suitable substrate for microbial growth and to produce natural bioactive compounds.RESULTSDiscarded fruit juices (DFJ) were treated and simultaneously valorized (producing microbial lipids) using a microbial consortium dominated by the photosynthetic cyanobacterium Leptolyngbya sp. The effects of N:P and C:N ratios on growth and lipid production were examined, along with the ability of the consortium to biotreat DFJ in laboratory‐scale (LS) reactors. Using the optimum nutrient ratios (N:P 5:1, C:N 50.2:1), scaled‐up reactors (aquariums) were then tested under suspended and attached growth conditions. The biomass produced was further exploited fo...
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A mixed microbial culture (MMC) of poly-hydroxy-alkanoates (PHAs) producers was developed in a draw- fill reactor (DFR) subjected to sequential nitrogen/carbon limitation stress using short chain fatty acids (SCFAs) as carbon source. The... more
A mixed microbial culture (MMC) of poly-hydroxy-alkanoates (PHAs) producers was developed in a draw- fill reactor (DFR) subjected to sequential nitrogen/carbon limitation stress using short chain fatty acids (SCFAs) as carbon source. The distribution of microorganisms was analyzed in the beginning of the process and after six weeks of limitation, in order to verify the domination of PHA producers in the consortium. The potential of the enhanced MMC for production of co-polymers was then evaluated in batch mode using synthetic media. The parameters tested were the C to N ratio (C/N), the propionate to butyric ratio (prop/but) and the initial pH (pHin). It was shown that the type, yields and productivity of PHAs was highly affected and the optimal yield, 40 % PHAs/dry cell weigh (DCW) (w/w), was achieved for a C/N of 200 (w/w), prop/but 10/90 (mol/mol) and pHin, 7.5. The MMC was further assessed for the production of PHAs from acidified sugary wastewater (ASW) containing SCFAs, sugars...
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The experimental design of the study was based on two different microbial processes, i.e. anaerobic fermentation of a sugar-based wastewater via mixed acidogenic cultures and aerobic polymerization of the produced acids and alcohols for... more
The experimental design of the study was based on two different microbial processes, i.e. anaerobic fermentation of a sugar-based wastewater via mixed acidogenic cultures and aerobic polymerization of the produced acids and alcohols for poly-hydroxy-alkanoates (PHAs) production, via enriched cultures. For the first stage of the combined process, a continuous up-flow column reactor (UFCR) and a continuous stirred tank reactor (CSTR) were developed. For the optimization of the performance of both reactors, the effect of main parameters influencing the distribution of the produced acids were investigated. The liquid effluent of the reactors, containing fatty acids and ethanol were forwarded to the second stage of the combined process. A sequential batch reactor (SBR) was used for the second, aerobic stage of PHAs production. The inoculum used for the start up of SBR was an enriched culture that was developed by thermally pretreated soil, subjected to nutrient limitation.
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In the present study, the valorization of cheese whey (CW) as an electron donor in an air-cathode single-chamber microbial fuel cell (MFC) was studied. Filter-sterilized raw and pretreated-acidified diluted CW (after 48 h of fermentation... more
In the present study, the valorization of cheese whey (CW) as an electron donor in an air-cathode single-chamber microbial fuel cell (MFC) was studied. Filter-sterilized raw and pretreated-acidified diluted CW (after 48 h of fermentation at mesophilic temperature) were used as substrates, in order to investigate the effect of the two different handlings on the MFC performance. The pretreatment-acidification experiments were performed under different operational conditions (initial dilutions giving chemical oxygen demand (COD) concentrations of 2 and 4 g/L as well as initial pH adjusted to 6.7 and without pH adjustment) in order to obtain maximum acidification efficiency and energy recovery, in the form of hydrogen. The effect of organic load on the efficiency of the MFC was studied, aiming at exploring the possibility of achieving a successful operation at the highest possible initial concentration of CW (smallest dilution). The experimental results showed that CW is a suitable and promising substrate for electricity production using MFC, with a maximum power density of 3.26 W/m 3 (0.33 MJ/kg COD) for filter-sterilized CW diluted to an initial concentration of 0.8 g COD/L. Combining MFC technology with the pretreatment/acidification process, during which hydrogen is also produced, a total energy of 2.37 MJ/kg COD could be recovered. Graphical abstract
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The present study evaluated the operational efficiency of a constructed wetland (CW) located at Andritsaina/Krestena municipality (Western Greece, Peloponnese, Greece), using a battery of tests and bioassays. Specifically, raw WWs... more
The present study evaluated the operational efficiency of a constructed wetland (CW) located at Andritsaina/Krestena municipality (Western Greece, Peloponnese, Greece), using a battery of tests and bioassays. Specifically, raw WWs entering the CW basins with broadleaf cattail Typha latifolia (raw-WWs) and biologically treated WWs effluents ending up in the adjustment tank were randomly collected in October, December 2018, and January 2019. Thereafter, freshwater algae (i.e., Chlorococcum sp., Scenedesmus sp.), invertebrates (i.e., Thamnocephalus platyurus, Brachionus calyciflorus), higher plant species (i.e., Sorghum saccharatum, Lepidium sativum and Sinapis alba) as well as human lymphocytes were treated with WWs for determining critical toxic endpoints in any case. The obtained data were further interpreted with physicochemical parameters, like total and dissolved COD (tCOD and dCOD respectively), total suspended solids (TSS) and volatile suspended solids (VSS), commonly measured ...
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The DOMUS_CW project proposes the adoption of a simple, cost efficient and highly effective practice for the treatment of domestic/household wastewaters in rural areas of Balkan and Mediterranean (BalkanMed) countries, i.e. treatment via... more
The DOMUS_CW project proposes the adoption of a simple, cost efficient and highly effective practice for the treatment of domestic/household wastewaters in rural areas of Balkan and Mediterranean (BalkanMed) countries, i.e. treatment via constructed wetlands (CWs). Two free surface flow CWs constructed in one Greek and one Cypriot community, were upgraded in order to serve as case studies to be further optimized via modeling. Through the systematic and detailed monitoring of the two CWs their operational efficiency was evaluated, and the response to operational factors that have not been extensively studied yet, such as supply variations and recirculation, were recorded and incorporated into the model. In addition, the effect and fate of xenobiotics, the interactions among plants and microorganisms, the toxic potency of effluents an the cropping frequency were evaluated aiming to the better understanding and thus further improvement of the operation of the systems. An exploitation p...
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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... more
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...
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The present study focuses on the exploitation of sweet sorghum biomass as a source for hydrogen in continuous and batch systems. Sweet sorghum is an annual C4 plant of tropical origin, well-adapted to sub-tropical and temperate regions... more
The present study focuses on the exploitation of sweet sorghum biomass as a source for hydrogen in continuous and batch systems. Sweet sorghum is an annual C4 plant of tropical origin, well-adapted to sub-tropical and temperate regions and highly productive in biomass. Sweet sorghum biomass is rich in readily fermentable sugars and thus it can be considered as an excellent raw material for fermentative hydrogen production. Extraction of free sugars from the sorghum stalks was achieved using water at 30°C. After the extraction process, a liquid fraction (sorghum extract), rich in sucrose, and a solid fraction (sorghum cellulosichemicellulosic residues), containing the cellulose and hemicelluloses, were obtained. Hydrogen production from sorghum extract was investigated using mixed acidogenic microbial cultures, coming from the indigenous sorghum microflora and Ruminococcus albus, an important, fibrolytic bacterium of the rumen. Hydrogen productivity of sorghum residues was assessed a...
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ABSTRACT This chapter discusses all the biological hydrogen production processes such as indirect and direct water biophotolysis, biological water gas shift, photo and dark fermentation and hydrogen production through microbial... more
ABSTRACT This chapter discusses all the biological hydrogen production processes such as indirect and direct water biophotolysis, biological water gas shift, photo and dark fermentation and hydrogen production through microbial electrolysis cells. Dark fermentation or fermentative hydrogen production is focused on this chapter, since it is considered as the most promising compared to all biological hydrogen production methods. However, there are significant remaining barriers to practical application. The chapter includes the limitations of each process and suggests several methods that are aimed at overcoming these barriers.
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The aim of the present study was to evaluate the effectiveness of a developed, ADM1-based kinetic model for the hydrogen production process in batch and continuous cultures of the bacterium Ruminococcus albus grown on sweet sorghum... more
The aim of the present study was to evaluate the effectiveness of a developed, ADM1-based kinetic model for the hydrogen production process in batch and continuous cultures of the bacterium Ruminococcus albus grown on sweet sorghum extract as the sole carbon source. Although sorghum extract is known to contain at least two different sugars, i.e. sucrose and glucose, no biphasic
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Research Interests: Bioinformatics, Biochemical Engineering, Bioenergy, Activated Sludge, Biodegradation, and 15 moreBiofuels, Biocompatibility, Bioreactor, Bioplastics, Biohydrogen, Biopolymers, Biodegradable Polymer, Bioprocessing, Biofuel cells, Bioreactors, Bioreactor Analysis and Design, Biodegradability, Bio Oil, Bioproducts, and Biomass Processing
Research Interests: Aquatic Toxicology, Biology, DNA damage, Medicine, Biological Sciences, and 15 moreGreece, Environmental Sciences, Animals, Acetylcholinesterase, Lipid peroxidation, CHEMICAL SCIENCES, Hemocytes, Marine Environment, Gills, Industrial Waste, Hemolymph, Biological markers, Gill, Mussel, and Micronucleus tests
The aim of the present study was to investigate the feasibly of using traditional milk kefir grains for the production of water kefir-like beverages and assess the changes in the physicochemical characteristics and the microbial... more
The aim of the present study was to investigate the feasibly of using traditional milk kefir grains for the production of water kefir-like beverages and assess the changes in the physicochemical characteristics and the microbial populations of the fermented beverages. To this end, experiments of milk fermentation were primarily conducted at different temperatures and upon selection of the optimal, a gradual substitution of the substrate was performed by replacing milk from a sucrose-based solution. After the successful fermentation of the sucrose substrate, fruit juices were used as fermentation substrates. Sensory evaluation of the sugar-based beverages was also performed in order to access their acceptability for consumption. According to the results, the transition from milk to water kefir is indeed feasible, leading to the production of beverages with relatively higher ethanol concentrations (up to 2.14 ± 0.12% w/v) than milk kefir and much lower lactic acid concentrations (up t...
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This chapter provides a guide on microbial biohydrogen technology via photosynthetic microorganisms, dark fermentation, and microbial electrolysis cells. The fundamentals of each technology are discussed, focusing on the principles of the... more
This chapter provides a guide on microbial biohydrogen technology via photosynthetic microorganisms, dark fermentation, and microbial electrolysis cells. The fundamentals of each technology are discussed, focusing on the principles of the implicated processes and the microbiology in each case, by analyzing the type, the metabolism, the role, and the possible interactions among microorganisms. Emphasis is also given on the different configurations and bioreactors that have been proposed in the literature so far, thus pointing the advantages, disadvantages, potentials, and limitations of each type towards scaling up. A brief mention is also made on the types of feedstock examined during application of each technology and on the storage and purification technologies of microbiologically produced biohydrogen.
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Considering that electronic wastes (e-wastes) have been recently recognized as a potent environmental and human threat, the present study aimed to assess the potential risk of personal computer motherboards (PCMBs) leaching into aquatic... more
Considering that electronic wastes (e-wastes) have been recently recognized as a potent environmental and human threat, the present study aimed to assess the potential risk of personal computer motherboards (PCMBs) leaching into aquatic media, following a real-life scenario. Specifically, PCMBs were submerged for 30 days in both distilled water (DW) and artificial seawater (ASW). Afterwards, PCMBs leachates were chemically characterized (i.e., total organic carbon, ions, and trace elements) and finally used (a) for culturing freshwater (Chlorococcum sp. and Scenedesmus rubescens) and saltwater (Dunaliella tertiolecta and Tisochrysis lutea) microalgae for 10 days (240 h), (b) as the exposure medium for mussel Mytilus galloprovincialis (96 h exposure), and (c) for performing the Cytokinesis Block Micronucleus (CBMN) assay in human lymphocytes cultures. According to the results, PCMBs could mediate both fresh- and marine algae growth rates over time, thus enhancing the cytotoxic, oxida...
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In this study biological pretreatment of willow sawdust (WSD) via the white rot fungi Leiotrametes menziesii and Abortiporus biennis was studied and the effect on biochemical methane potential (BMP), was evaluated. Two sets of solid state... more
In this study biological pretreatment of willow sawdust (WSD) via the white rot fungi Leiotrametes menziesii and Abortiporus biennis was studied and the effect on biochemical methane potential (BMP), was evaluated. Two sets of solid state fermentation (SSF) batch experiments were performed, during which the fractionation of lignocellulosic biomass, was assessed. Scanning electron microscopy (SEM) and IR spectra were used to investigate the changes in the structural characteristics of the pretreated WSD. Samples of 15d and 30d of cultivation period (i.e. the middle and the end of the pretreatment experiment) were used for BMP tests, in batch mesophilic reactors and the duration of the pretreatment effect, was also evaluated. In addition, combination of biological (30 d cultivation period) 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. For rea...
In the present study the exploitation of a starchy food waste containing mainly wasted rice (WR) was investigated for bioethanol production via novel yeast strains. The saccharification efficiency of different pretreatment schemes was... more
In the present study the exploitation of a starchy food waste containing mainly wasted rice (WR) was investigated for bioethanol production via novel yeast strains. The saccharification efficiency of different pretreatment schemes was initially evaluated aiming to the maximum liberation of free sugars, and their subsequent fermentation towards enhanced ethanol yields. Three approaches of pretreatment were investigated i.e. enzymatic pretreatment via commercial amylolytic enzymes, thermochemical pretreatment via HCl and combined chemical-enzymatic pretreatment with initial solids loading of WR 10 30% TS WR. Fermentation tests of the pretreated WR were performed via different newly isolated yeast and the fermentation efficiency was comparatively assessed. It was shown that the combined pretreatment led to the maximum saccharification of the waste, whereas ethanol yields were in in all cases quite high, exceeding 85% of the theoretical maximum. Introduction Due to the steadily increasi...
The aim of the present study is to investigate the feasibility of exploiting olive oil mill wastewater (OOMW) for PHAs production by pure culture of Pseudomonas sp. Four different strains belonging to the Pseudomonas genus were isolated... more
The aim of the present study is to investigate the feasibility of exploiting olive oil mill wastewater (OOMW) for PHAs production by pure culture of Pseudomonas sp. Four different strains belonging to the Pseudomonas genus were isolated from an ‘enriched’ mixed culture that was developed using activated sludge from the municipal wastewater treatment plant of the city of Patras (Greece) as inoculum. The enrichment was performed by subjecting the culture to sequential cycles of carbon and nitrogen limitation to ensure that the predominant strains would be PHAs forming bacteria. To estimate the maximum capacity of PHAs production under favorable conditions, batch experiments were carried out under nitrogen limitation and continuous aeration using synthetic substrate with volatile fatty acids (VFAs) that is acetate, propionate, butyrate as carbon source with both mixed culture as well as all isolates. It was shown that the mixed culture had the best performance as far as PHAs yield is c...
Research Interests: Bioinformatics, Biochemical Engineering, Catalysis, Biotechnology, Bioenergy, and 15 moreChemical and Biological Engineering, Biological Sciences, Biodegradation, Biofuels, Biocompatibility, Biosystems engineering, Bioplastics, Bioprocessing, Biofuel cells, Biotransformation, Biodegradability, Bio Oil, Biopolyesters, Bioproducts, and Biomass Processing
The aim of this chapter is to provide a description of the main methods used to assess biological transformation of biomass. It will address saccharification tests which account for the ability of biomass to release sugars during... more
The aim of this chapter is to provide a description of the main methods used to assess biological transformation of biomass. It will address saccharification tests which account for the ability of biomass to release sugars during enzymatic hydrolysis. Biochemical methane potential (BMP) tests, which are widely used to assess anaerobic digestibility of biomass for the production of methane and BMP prediction by near infra-red spectroscopy will be presented. Biohydrogen potential (BHP), used to assess the ability to produce biohydrogen from biomass by dark fermentation will be described. Respirometry tests accounting for assessing aerobic degradability of biomass will be described. Incubation tests used to assess carbon and nitrogen degradation in soils will also be presented.
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 H2SO4 (1 wt%) and AlCl3·6H2O (30 mol % with... more
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 H2SO4 (1 wt%) and AlCl3·6H2O (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.
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The scope of the present study was to identify the most effective and less toxic combination of various organic solvents and extractants for the extraction of Cr(VI) from synthetic wastewaters with extremely high chromium concentration... more
The scope of the present study was to identify the most effective and less toxic combination of various organic solvents and extractants for the extraction of Cr(VI) from synthetic wastewaters with extremely high chromium concentration (up to 1,000 ppm) in order to be further used in a novel two-liquid-phase bioreactor for microbial reduction of Cr(VI). In terms of organic solvents, hexane, heptane, chloroform, ethyl-acetate, and kerosene were tested, whereas Aliquat 336, TOPO, and TPB were used as extractants. The effect of the pH of the aqueous phase and of the ratio of organic to aqueous phase were studied in terms of Cr(VI) extraction. The extraction capacities of different combinations of solvents/extractants and the addition of 1-hexanol as a stabilizer for the most effective separation of phases were also assessed. Moreover, the toxicity of each solvent was assessed using acclimated mixed consortia. The acclimated, enriched culture was further used as inoculums for the start ...
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The present study aims to assess the impact of the type of yeast consortium used during bioethanol production from starchy biowastes and to determine the optimal fermentation conditions for enhanced bioethanol production. Three different... more
The present study aims to assess the impact of the type of yeast consortium used during bioethanol production from starchy biowastes and to determine the optimal fermentation conditions for enhanced bioethanol production. Three different yeast strains, Saccharomyces cerevisiae, Pichia barkeri, and Candida intermedia were used in mono- and co-cultures with pretreated waste-rice as substrate. The optimization of fermentation conditions i.e., fermentation time, temperature, pH, and inoculum size, was investigated in small-scale batch cultures and subsequently, the optimal conditions were applied for scaling-up and validation of the process in a 7-L fermenter. It was shown that co-culturing of yeasts either in couples or triples significantly enhanced the fermentation efficiency of the process, with ethanol yield reaching 167.80 ± 0.49 g/kg of biowaste during experiments in the fermenter.
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In the current study, a domestic food waste containing more than 50% of carbohydrates was assessed as feedstock to produce second-generation bioethanol. Aiming to the maximum exploitation of the carbohydrate fraction of the waste, its... more
In the current study, a domestic food waste containing more than 50% of carbohydrates was assessed as feedstock to produce second-generation bioethanol. Aiming to the maximum exploitation of the carbohydrate fraction of the waste, its hydrolysis via cellulolytic and amylolytic enzymatic blends was investigated and the saccharification efficiency was assessed in each case. Fermentation experiments were performed using the non-conventional yeast Pichia anomala (Wickerhamomyces anomalus) under both separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) modes to evaluate the conversion efficiencies and ethanol yields for different enzymatic loadings. It was shown that the fermentation efficiency of the yeast was not affected by the fermentation mode and was high for all handlings, reaching 83%, whereas the enzymatic blend containing the highest amount of both cellulolytic and amylolytic enzymes led to almost complete liquefaction of the waste...