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This paper presents major gaps and challenges for implementing the UN Decade of Ocean Science for Sustainable Development (2021-2030) in the Mediterranean region. The authors make recommendations on the scientific knowledge needs and co-design actions identified during two consultations, part of the Decade preparatory-phase, framing them in the Mediterranean Sea’s unique environmental and socio-economic perspectives. According to the ‘Mediterranean State of the Environment and Development Report 2020’ by the United Nations Environment Programme Mediterranean Action Plan and despite notable progress, the Mediterranean region is not on track to achieve and fully implement the Sustainable Development Goals of Agenda 2030. Key factors are the cumulative effect of multiple human-induced pressures that threaten the ecosystem resources and services in the global change scenario. The basin, identified as a climate change vulnerability hotspot, is exposed to pollution and rising impacts of climate change. This affects mainly the coastal zones, at increasing risk of extreme events and their negative effects of unsustainable management of key economic assets. Transitioning to a sustainable blue economy is the key for the marine environment’s health and the nourishment of future generations. This challenging context, offering the opportunity of enhancing the knowledge to define science-based measures as well as narrowing the gaps between the Northen and Southern shores, calls for a joint (re)action. The paper reviews the state of the art of Mediterranean Sea science knowledge, sets of trends, capacity development needs, specific challenges, and recommendations for each Decade’s societal outcome. In the conclusions, the proposal for a Mediterranean regional programme in the framework of the Ocean Decade is addressed. The core objective relies on integrating and improving the existing ocean-knowledge, Ocean Literacy, and ocean observing capacities building on international cooper

This paper presents major gaps and challenges for implementing the UN Decade of Ocean Science for Sustainable Development (2021-2030) in the Mediterranean region. The authors make recommendations on the scientific knowledge needs and co-design actions identified during two consultations, part of the Decade preparatory-phase, framing them in the Mediterranean Sea’s unique environmental and socio-economic perspectives. According to the ‘Mediterranean State of the Environment and Development Report 2020’ by the United Nations Environment Programme Mediterranean Action Plan and despite notable progress, the Mediterranean region is not on track to achieve and fully implement the Sustainable Development Goals of Agenda 2030. Key factors are the cumulative effect of multiple human-induced pressures that threaten the ecosystem resources and services in the global change scenario. The basin, identified as a climate change vulnerability hotspot, is exposed to pollution and rising impacts of climate change. This affects mainly the coastal zones, at increasing risk of extreme events and their negative effects of unsustainable management of key economic assets. Transitioning to a sustainable blue economy is the key for the marine environment’s health and the nourishment of future generations. This challenging context, offering the opportunity of enhancing the knowledge to define science-based measures as well as narrowing the gaps between the Northen and Southern shores, calls for a joint (re)action. The paper reviews the state of the art of Mediterranean Sea science knowledge, sets of trends, capacity development needs, specific challenges, and recommendations for each Decade’s societal outcome. In the conclusions, the proposal for a Mediterranean regional programme in the framework of the Ocean Decade is addressed. The core objective relies on integrating and improving the existing ocean-knowledge, Ocean Literacy, and ocean observing capacities building on international cooper

Ultra-processed foods (UPFs) are negatively perceived by part of the scientific community, the public, and policymakers alike, to the extent they are sometimes referred to as not “real food”. Many observational surveys have linked consumption of UPFs to adverse health outcomes. This narrative synthesis and scientific reappraisal of available evidence aims to: (i) critically evaluate UPF-related scientific literature on diet and disease and identify possible research gaps or biases in the interpretation of data; (ii) emphasize the innovative potential of various processing technologies that can lead to modifications of the food matrix with beneficial health effects; (iii) highlight the possible links between processing, sustainability and circular economy through the valorisation of by-products; and (iv) delineate the conceptual parameters of new paradigms in food evaluation and classification systems. Although greater consumption of UPFs has been associated with obesity, unfavorable cardiometabolic risk factor profiles, and increased risk for non-communicable diseases, whether specific food processing techniques leading to ultra-processed formulations are responsible for the observed links between UPFs and various health outcomes remains elusive and far from being understood. Evolving technologies can be used in the context of sustainable valorisation of food processing by-products to create novel, low-cost UPFs with improved nutritional value and health potential. New paradigms of food evaluation and assessment should be funded and developed on several novel pillars - enginomics, signalling, and precision nutrition - taking advantage of available digital technologies and artificial intelligence. Research is needed to generate required scientific knowledge to either expand the current or create new food evaluation and classification systems, incorporating processing aspects that may have a significant impact on health and wellness, together with factors related t

Ultra-processed foods (UPFs) are negatively perceived by part of the scientific community, the public, and policymakers alike, to the extent they are sometimes referred to as not “real food”. Many observational surveys have linked consumption of UPFs to adverse health outcomes. This narrative synthesis and scientific reappraisal of available evidence aims to: (i) critically evaluate UPF-related scientific literature on diet and disease and identify possible research gaps or biases in the interpretation of data; (ii) emphasize the innovative potential of various processing technologies that can lead to modifications of the food matrix with beneficial health effects; (iii) highlight the possible links between processing, sustainability and circular economy through the valorisation of by-products; and (iv) delineate the conceptual parameters of new paradigms in food evaluation and classification systems. Although greater consumption of UPFs has been associated with obesity, unfavorable cardiometabolic risk factor profiles, and increased risk for non-communicable diseases, whether specific food processing techniques leading to ultra-processed formulations are responsible for the observed links between UPFs and various health outcomes remains elusive and far from being understood. Evolving technologies can be used in the context of sustainable valorisation of food processing by-products to create novel, low-cost UPFs with improved nutritional value and health potential. New paradigms of food evaluation and assessment should be funded and developed on several novel pillars - enginomics, signalling, and precision nutrition - taking advantage of available digital technologies and artificial intelligence. Research is needed to generate required scientific knowledge to either expand the current or create new food evaluation and classification systems, incorporating processing aspects that may have a significant impact on health and wellness, together with factors related t

This paper presents major gaps and challenges for implementing the UN Decade of Ocean Science for Sustainable Development (2021-2030) in the Mediterranean region. The authors make recommendations on the scientific knowledge needs and co-design actions identified during two consultations, part of the Decade preparatory-phase, framing them in the Mediterranean Sea’s unique environmental and socio-economic perspectives. According to the ‘Mediterranean State of the Environment and Development Report 2020’ by the United Nations Environment Programme Mediterranean Action Plan and despite notable progress, the Mediterranean region is not on track to achieve and fully implement the Sustainable Development Goals of Agenda 2030. Key factors are the cumulative effect of multiple human-induced pressures that threaten the ecosystem resources and services in the global change scenario. The basin, identified as a climate change vulnerability hotspot, is exposed to pollution and rising impacts of climate change. This affects mainly the coastal zones, at increasing risk of extreme events and their negative effects of unsustainable management of key economic assets. Transitioning to a sustainable blue economy is the key for the marine environment’s health and the nourishment of future generations. This challenging context, offering the opportunity of enhancing the knowledge to define science-based measures as well as narrowing the gaps between the Northen and Southern shores, calls for a joint (re)action. The paper reviews the state of the art of Mediterranean Sea science knowledge, sets of trends, capacity development needs, specific challenges, and recommendations for each Decade’s societal outcome. In the conclusions, the proposal for a Mediterranean regional programme in the framework of the Ocean Decade is addressed. The core objective relies on integrating and improving the existing ocean-knowledge, Ocean Literacy, and ocean observing capacities building on international cooper

The city of Riga, being at the forefront of fighting climate change, is in the process of updating their energy planning document, the Riga Smart City Sustainable Energy Action Plan, for the planning period 2020–2030. As Riga surpassed the emission reduction target of the EU for 2030, there is an opportunity for a new ambitious goal and innovative actions to accomplishit. Considering the Intergovernmental Panel on Climate Change’s (IPCC) recommendation of not exceeding a world average temperature increase of 2° C, suitable targets for Riga are a reduction by 61% (2030) and 70% (2050), respectively, compared to 1990 levels. This paper presents pathways that contain measures that are complementary to the planned actions of Riga and focus on three thematic areas: green hydrogen, solar engagement, and modern transportation. The measures consist of successful European actions modified and applied to the characteristics of Riga. The production of green hydrogen is economically feasible for the city of Riga, achieving a Levelized Cost of Electricity (LCOE) of 0.0395 EUR/kWh and a Levelized Cost of Hydrogen (LCOH) of 3.62 EUR/kgH2. While rooftop solar PV systems are an attractive option for the citizens of Riga if a feed-in tariff of 0.1 EUR/kWh is granted, the employment of solar thermal collectors is not advisable due to the high breakeven duration. Including citizens in renewable projects in the form of voucher return packages is a welcomed alternative loan scheme benefiting both the municipality and the citizens. Furthermore, the development of a microalgae carbon capture pilot project could leverage Riga’s role as an innovation hub. The creation of a fossil-free last-mile delivery zone in the city centre would tackle the challenge of reducing road emissions as electric cargo bicycles have the potential of decreasing emissions by around 99% per trip, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energia

La ricerca, nell’ambito del progetto europeo Kill Spill, riguarda l’applicazione del soil washing in scala di laboratorio al risanamento ex-situ di sabbie contaminate da carburante marino IFO180, mediante agenti mobilizzanti biogeni e surfattanti microbici, non-tossici e biodegradabili. Gli agenti testati differiscono per origine (vegetale, animale, microbica) e per proprietà chimiche (carattere idrofilo/lipofilo). Essi sono: acidi biliari, due tipi di ciclodestrine – idrossipropil-beta-ciclodestrine (HPB-CD) e beta-ciclodestrine metilate (RAMEB) – due lecitine di soia – disoleata (SL) e grezza (Textrol F10) – 4 detergenti commerciali (ditta BioBased Europe) tre surfattanti microbici – ramnolipidi (RL), soforolipidi (SR) e surfattine (SF) - e Triton X-100 (TX), surfattante sintetico di confronto. Iniziali washing di screening (24 ore) hanno permesso di selezionare i 3 agenti migliori (SL, HPB-CD e SR), utilizzati nella successiva ottimizzazione dei parametri operativi (concentrazione del surfattante, concentrazione di IFO180, rapporto acqua/sabbia, velocità di miscelazione), tramite il disegno statistico sperimentale CCD e la Response Surface Methodology (RSM). Per ciascun agente (oltre TX e blank) sono stati identificati i parametri operativi e gli effetti di interazione che influenzano significativamente le performance del processo. I modelli predittivi, sperimentalmente validati, sono stati interrogati per identificare le condizioni operative ottimali (massima rimozione di idrocarburi possibile, minimo consumo di acqua) per diverse livelli di contaminazione delle sabbie. SL consente, in condizioni ottimali, di rimuovere meglio gli idrocarburi di quanto faccia il TX. Analoghi risultati si ottengono per HPB-CD e SR, per basse contaminazioni. Sono state valutate le frazioni IPA (idrocarburi policiclici aromatici) e n-alcani in IFO180, unitamente alle rese di rimozione delle due distinte frazioni dalle sabbie contaminate, nei casi considerati ottimali per il processo, The present work, related to European project Kill Spill, concerns the application of soil washing on a laboratory scale for the ex-situ remediation of contaminated sands by marine fuel IFO180 using mobilizing biogenic agents and surfactants microbial, non-toxic and biodegradable. The tested agents differ in origin (plant, animal, microbial) and chemical properties (hydrophilic/lipophilic character). They are: bile acids; two types of - hydroxypropyl-beta-cyclodextrins (HPB-CD) e methylatedbeta-cyclodextrins (RAMEB) - two soy lecithin - oil free (SL) and coarse (Textrol F10) - 4 commercial detergents (Bio-based company Europe), three microbial surfactants - ramnolipidi (RL), soforolipidi (SR) and surfattine (SF) and Triton X-100 (TX) as synthetic comparison surfactant. After the screening phase (washing applied to contaminated sands for 24 hours) were selected the 3 best performing agents (SL, HPB-CD and SR), used in the subsequent optimization of operating parameters (concentration of surfactants, concentration of IFO180, ratio water/sand and mixing rate), through statistical experimental design CCD and the Response Surface Methodology (RSM). For each agent (over TX and blank) were identified operational parameters and the interaction effects that significantly influence the performance of washing process. The predictive models, experimentally validated, were used to identify the optimum operating conditions (maximum possible removal of hydrocarbons, minimum water consumption) for different levels of sands contamination. SL allows, under optimal conditions, better hydrocarbons removal(%) than TX does. Similar results are obtained for HPB-CD and SR, for low sands contamination. the IPA fractions (polycyclic aromatic hydrocarbons) and n-alkanes in IFO180 were evaluated, together with the removal(%) of two distinct fractions from contaminated sands, in the cases considered as optimal for the washing process. For the best agent (SL) was studied the effect of the washi

Aiming to reduce the cost of production of polyhydroxyalkanoates (PHAs), it was verified the use of two agro-industrial wastes as alternatives carbon sources for the production of: A- poly(hydroxybutyrate-co-hydroxyvalerate), from olive mill wastewater (2012 campaign; 60% dephenolised). It was possible to used up to 25% v/v in the culture media due to the presence of polyphenolic inhibitors in the matrix. B- polyhydroxybutyrate (PHB) with OMW belonging to 2013 (>70% dephenolised): the culture medium could contain 100% v/v without causing inhibition. An integrated biorefinery scheme was defined and tested sequentially: polyphenols recovery, organic acids PHAs and biogas production. C- PHB from dephenolised and fermented grape pomace. An integrated biorefinery scheme was proposed for the first time for the valorisation of grape pomace. D- medium chain length polyhydroxyalkanoates by performing the anaerobic acidogenic digestion of GP before dephenolisation. From the research work on OMW, a study about total polyphenols determination by colorimetric method was carried out. Indeed, solid phase extraction break-through curves obtained during polyphenols recovery experiment were employed as a tool for the analysis. To increase the volatile fatty acids (VFAs) concentration, for obtaining a feeding solution which allow fed-batch fermentation, it was proposed to concentrate VFAs produced in acidogenic digestion using nanofiltration (NF). A preliminary feasibility study has been carried out, getting rejections in the range 30-90%, using a plant-counter and prepared in the laboratory of VFAS solution (C2 to C6) salts and buffers in distilled water. The optimization of the PHAs downstream process was also studied. It is been developed a procedure for the extraction of PHAs by cell pretreatment with, heat, acids, digestion with NaOH and ethanol-water washing. In this study it was verified that the implementation of a pre-treatment with H2SO4 allows to recover 85% of PHAs product

La ricerca, nell’ambito del progetto europeo Kill Spill, riguarda l’applicazione del soil washing in scala di laboratorio al risanamento ex-situ di sabbie contaminate da carburante marino IFO180, mediante agenti mobilizzanti biogeni e surfattanti microbici, non-tossici e biodegradabili. Gli agenti testati differiscono per origine (vegetale, animale, microbica) e per proprietà chimiche (carattere idrofilo/lipofilo). Essi sono: acidi biliari, due tipi di ciclodestrine – idrossipropil-beta-ciclodestrine (HPB-CD) e beta-ciclodestrine metilate (RAMEB) – due lecitine di soia – disoleata (SL) e grezza (Textrol F10) – 4 detergenti commerciali (ditta BioBased Europe) tre surfattanti microbici – ramnolipidi (RL), soforolipidi (SR) e surfattine (SF) - e Triton X-100 (TX), surfattante sintetico di confronto. Iniziali washing di screening (24 ore) hanno permesso di selezionare i 3 agenti migliori (SL, HPB-CD e SR), utilizzati nella successiva ottimizzazione dei parametri operativi (concentrazione del surfattante, concentrazione di IFO180, rapporto acqua/sabbia, velocità di miscelazione), tramite il disegno statistico sperimentale CCD e la Response Surface Methodology (RSM). Per ciascun agente (oltre TX e blank) sono stati identificati i parametri operativi e gli effetti di interazione che influenzano significativamente le performance del processo. I modelli predittivi, sperimentalmente validati, sono stati interrogati per identificare le condizioni operative ottimali (massima rimozione di idrocarburi possibile, minimo consumo di acqua) per diverse livelli di contaminazione delle sabbie. SL consente, in condizioni ottimali, di rimuovere meglio gli idrocarburi di quanto faccia il TX. Analoghi risultati si ottengono per HPB-CD e SR, per basse contaminazioni. Sono state valutate le frazioni IPA (idrocarburi policiclici aromatici) e n-alcani in IFO180, unitamente alle rese di rimozione delle due distinte frazioni dalle sabbie contaminate, nei casi considerati ottimali per il processo, The present work, related to European project Kill Spill, concerns the application of soil washing on a laboratory scale for the ex-situ remediation of contaminated sands by marine fuel IFO180 using mobilizing biogenic agents and surfactants microbial, non-toxic and biodegradable. The tested agents differ in origin (plant, animal, microbial) and chemical properties (hydrophilic/lipophilic character). They are: bile acids; two types of - hydroxypropyl-beta-cyclodextrins (HPB-CD) e methylatedbeta-cyclodextrins (RAMEB) - two soy lecithin - oil free (SL) and coarse (Textrol F10) - 4 commercial detergents (Bio-based company Europe), three microbial surfactants - ramnolipidi (RL), soforolipidi (SR) and surfattine (SF) and Triton X-100 (TX) as synthetic comparison surfactant. After the screening phase (washing applied to contaminated sands for 24 hours) were selected the 3 best performing agents (SL, HPB-CD and SR), used in the subsequent optimization of operating parameters (concentration of surfactants, concentration of IFO180, ratio water/sand and mixing rate), through statistical experimental design CCD and the Response Surface Methodology (RSM). For each agent (over TX and blank) were identified operational parameters and the interaction effects that significantly influence the performance of washing process. The predictive models, experimentally validated, were used to identify the optimum operating conditions (maximum possible removal of hydrocarbons, minimum water consumption) for different levels of sands contamination. SL allows, under optimal conditions, better hydrocarbons removal(%) than TX does. Similar results are obtained for HPB-CD and SR, for low sands contamination. the IPA fractions (polycyclic aromatic hydrocarbons) and n-alkanes in IFO180 were evaluated, together with the removal(%) of two distinct fractions from contaminated sands, in the cases considered as optimal for the washing process. For the best agent (SL) was studied the effect of the washi

Aiming to reduce the cost of production of polyhydroxyalkanoates (PHAs), it was verified the use of two agro-industrial wastes as alternatives carbon sources for the production of: A- poly(hydroxybutyrate-co-hydroxyvalerate), from olive mill wastewater (2012 campaign; 60% dephenolised). It was possible to used up to 25% v/v in the culture media due to the presence of polyphenolic inhibitors in the matrix. B- polyhydroxybutyrate (PHB) with OMW belonging to 2013 (>70% dephenolised): the culture medium could contain 100% v/v without causing inhibition. An integrated biorefinery scheme was defined and tested sequentially: polyphenols recovery, organic acids PHAs and biogas production. C- PHB from dephenolised and fermented grape pomace. An integrated biorefinery scheme was proposed for the first time for the valorisation of grape pomace. D- medium chain length polyhydroxyalkanoates by performing the anaerobic acidogenic digestion of GP before dephenolisation. From the research work on OMW, a study about total polyphenols determination by colorimetric method was carried out. Indeed, solid phase extraction break-through curves obtained during polyphenols recovery experiment were employed as a tool for the analysis. To increase the volatile fatty acids (VFAs) concentration, for obtaining a feeding solution which allow fed-batch fermentation, it was proposed to concentrate VFAs produced in acidogenic digestion using nanofiltration (NF). A preliminary feasibility study has been carried out, getting rejections in the range 30-90%, using a plant-counter and prepared in the laboratory of VFAS solution (C2 to C6) salts and buffers in distilled water. The optimization of the PHAs downstream process was also studied. It is been developed a procedure for the extraction of PHAs by cell pretreatment with, heat, acids, digestion with NaOH and ethanol-water washing. In this study it was verified that the implementation of a pre-treatment with H2SO4 allows to recover 85% of PHAs product

Emerging pollutants reach the environment from various anthropogenic sources and are distributed throughout environmental matrices. Although great advances have been made in the detection and analysis of trace pollutants during recent decades, due to the continued development and refinement of specific techniques, a wide array of undetected contaminants of emerging environmental concern need to be identified and quantified in various environmental components and biological tissues. These pollutants may be mobile and persistent in air, water, soil, sediments and ecological receptors even at low concentrations. Robust data on their fate and behaviour in the environment, as well as on threats to ecological and human health, are still lacking. Moreover, the ecotoxicological significance of some emerging micropollutants remains largely unknown, because satisfactory data to determine their risk often do not exist. This paper discusses the fate, behaviour, (bio)monitoring, environmental and health risks associated with emerging chemical (pharmaceuticals, endocrine disruptors, hormones, toxins, among others) and biological (bacteria, viruses) micropollutants in soils, sediments, groundwater, industrial and municipal wastewaters, aquaculture effluents, and freshwater and marine ecosystems, and highlights new horizons for their (bio)removal. Our study aims to demonstrate the imperative need to boost research and innovation for new and cost-effective treatment technologies, in line with the uptake, mode of action and consequences of each emerging contaminant. We also address the topic of innovative tools for the evaluation of the effects of toxicity on human health and for the prediction of microbial availability and degradation in the environment. Additionally, we consider the development of (bio)sensors to perform environmental monitoring in real-time mode. This needs to address multiple species, along with a more effective exploitation of specialised microbes or enzymes cap

The investigation of phylogenetic diversity and functionality of complex microbial communities in relation to changes in the environmental conditions represents a major challenge of microbial ecology research. Nowadays, particular attention is paid to microbial communities occurring at environmental sites contaminated by recalcitrant and toxic organic compounds. Extended research has evidenced that such communities evolve some metabolic abilities leading to the partial degradation or complete mineralization of the contaminants. Determination of such biodegradation potential can be the starting point for the development of cost effective biotechnological processes for the bioremediation of contaminated matrices. This work showed how metagenomics-based microbial ecology investigations supported the choice or the development of three different bioremediation strategies. First, PCR-DGGE and PCR-cloning approaches served the molecular characterization of microbial communities enriched through sequential development stages of an aerobic cometabolic process for the treatment of groundwater contaminated by chlorinated aliphatic hydrocarbons inside an immobilized-biomass packed bed bioreactor (PBR). In this case the analyses revealed homogeneous growth and structure of immobilized communities throughout the PBR and the occurrence of dominant microbial phylotypes of the genera Rhodococcus, Comamonas and Acidovorax, which probably drive the biodegradation process. The same molecular approaches were employed to characterize sludge microbial communities selected and enriched during the treatment of municipal wastewater coupled with the production of polyhydroxyalkanoates (PHA). Known PHA-accumulating microorganisms identified were affiliated with the genera Zooglea, Acidovorax and Hydrogenophaga. Finally, the molecular investigation concerned communities of polycyclic aromatic hydrocarbon (PAH) contaminated soil subjected to rhizoremediation with willow roots or fertilization-ba

Marine sediments are the main accumulation reservoir of organic recalcitrant pollutants such as polychlorinated biphenyls (PCBs). In the anoxic conditions typical of these sediments, anaerobic bacteria of the phylum Chloroflexi are able to attack these compounds in a process called microbial reductive dechlorination. Such activity and members of this phylum were detected in PCB-impacted sediments of the Venice Lagoon. The aim of this work was to investigate microbial reductive dechlorination and design bioremediation approaches for marine sediments of the area. Three out of six sediment cultures from different sampling areas exhibited dechlorination activities in the same conditions of the site and two phylotypes (VLD-1 and VLD-2) were detected and correlated to this metabolism. Biostimulation was tested on enriched dechlorinating sediment cultures from the same site using five different electron donors, of which lactate was the best biostimulating agent; complementation of microbial and chemical dechlorination catalyzed by biogenic zerovalent Pd nanoparticles was not effective due to sulfide poisoning of the catalyst. A new biosurfactant-producing strain of Shewanella frigidimarina was concomitantly obtained from hydrocarbon-degrading marine cultures and selected because of the low toxicity of its product. All these findings were then exploited to develop bioremediation lab-scale tests in shaken reactors and static microcosms on real sediments and water of the Venice lagoon, testing i) a bioaugmentation approach, with a selected enriched sediment culture from the same area, ii) a biostimulation approach with lactate as electron donor, iii) a bioavailability enhancement with the supplementation of the newly-discovered biosurfactant, and iv) all possible combinations of the afore-mentioned approaches. The best bioremediation approach resulted to be a combination of bioaugmentation and bioremediation and it could be a starting point to design bioremediation process fo

The investigation of phylogenetic diversity and functionality of complex microbial communities in relation to changes in the environmental conditions represents a major challenge of microbial ecology research. Nowadays, particular attention is paid to microbial communities occurring at environmental sites contaminated by recalcitrant and toxic organic compounds. Extended research has evidenced that such communities evolve some metabolic abilities leading to the partial degradation or complete mineralization of the contaminants. Determination of such biodegradation potential can be the starting point for the development of cost effective biotechnological processes for the bioremediation of contaminated matrices. This work showed how metagenomics-based microbial ecology investigations supported the choice or the development of three different bioremediation strategies. First, PCR-DGGE and PCR-cloning approaches served the molecular characterization of microbial communities enriched through sequential development stages of an aerobic cometabolic process for the treatment of groundwater contaminated by chlorinated aliphatic hydrocarbons inside an immobilized-biomass packed bed bioreactor (PBR). In this case the analyses revealed homogeneous growth and structure of immobilized communities throughout the PBR and the occurrence of dominant microbial phylotypes of the genera Rhodococcus, Comamonas and Acidovorax, which probably drive the biodegradation process. The same molecular approaches were employed to characterize sludge microbial communities selected and enriched during the treatment of municipal wastewater coupled with the production of polyhydroxyalkanoates (PHA). Known PHA-accumulating microorganisms identified were affiliated with the genera Zooglea, Acidovorax and Hydrogenophaga. Finally, the molecular investigation concerned communities of polycyclic aromatic hydrocarbon (PAH) contaminated soil subjected to rhizoremediation with willow roots or fertilization-ba

Marine sediments are the main accumulation reservoir of organic recalcitrant pollutants such as polychlorinated biphenyls (PCBs). In the anoxic conditions typical of these sediments, anaerobic bacteria of the phylum Chloroflexi are able to attack these compounds in a process called microbial reductive dechlorination. Such activity and members of this phylum were detected in PCB-impacted sediments of the Venice Lagoon. The aim of this work was to investigate microbial reductive dechlorination and design bioremediation approaches for marine sediments of the area. Three out of six sediment cultures from different sampling areas exhibited dechlorination activities in the same conditions of the site and two phylotypes (VLD-1 and VLD-2) were detected and correlated to this metabolism. Biostimulation was tested on enriched dechlorinating sediment cultures from the same site using five different electron donors, of which lactate was the best biostimulating agent; complementation of microbial and chemical dechlorination catalyzed by biogenic zerovalent Pd nanoparticles was not effective due to sulfide poisoning of the catalyst. A new biosurfactant-producing strain of Shewanella frigidimarina was concomitantly obtained from hydrocarbon-degrading marine cultures and selected because of the low toxicity of its product. All these findings were then exploited to develop bioremediation lab-scale tests in shaken reactors and static microcosms on real sediments and water of the Venice lagoon, testing i) a bioaugmentation approach, with a selected enriched sediment culture from the same area, ii) a biostimulation approach with lactate as electron donor, iii) a bioavailability enhancement with the supplementation of the newly-discovered biosurfactant, and iv) all possible combinations of the afore-mentioned approaches. The best bioremediation approach resulted to be a combination of bioaugmentation and bioremediation and it could be a starting point to design bioremediation process fo

Copolymers of poly(butylene succinate) (PBS) containing thiodiethylene succinate sequences with different molecular architectures (PBSPTDGS) were prepared via reactive blending in the presence of a Ti-based catalyst. In particular, a block copolymer with long sequences and a random one have been investigated for their biodegradability. The parent homopolymer PBS has been also synthesized via the usual two-stage melt polycondensation and used as reference polymer in the study. The hydrolitic treatment carried out using lipase from Candida cylindracea ([E] = 50 U/ml, T = 30 °C and pH = 7.0), showed that copolymers biodegraded more rapidly and extensively than PBS. ATRIR analysis and DSC measurements also performed on the resulting samples showed that the enzyme simultaneously attacks the amorphous phase and the PTDGS crystalline phase, which is characterized by lower packing density and degree of perfection with respect to the PBS one. This result suggested that the higher degradability of the copolymers under study can be correlated both to the crystallinity degree and to the nature of the crystalline phase. NMR analysis, performed to detect changes in composition of the copolymers during the degradation, demonstrated that enzyme hydrolysis preferentially targeted ester groups of TDGS sequences because of their higher hydrophilicity. © 2013 Elsevier Ltd. All rights reserved.

Biological invasion is widely studied, however, conclusions on the outcome of this process mainly originate from observations in systems that leave a large number of experimental variables uncontrolled. Here using a fully controlled system consisting of assembled bacterial communities, we evaluate the degree of invasion and the effect on the community functionality in relation to the initial community evenness under specific environmental stressors. We show that evenness influences the level of invasion and that the introduced species can promote functionality under stress. The evenness-invasibility relationship is negative in the absence and neutral in the presence of stress. Under these conditions, the introduced species is able to maintain the functionality of uneven communities. These results indicate that communities, initially having the same genetic background, in the presence of the same invader, react in a different way with respect to invasibility and functionality depending on specific environmental conditions and community evenness.

[No abstract available]

[No abstract available]

Bioconversion of ferulic acid to vanillin represents an attractive opportunity for replacing synthetic vanillin with a bio-based product, that can be label “natural”, according to current food regulations. Ferulic acid is an abundant phenolic compound in cereals processing by-products, such as wheat bran, where it is linked to the cell wall constituents. In this work, the possibility of producing vanillin from ferulic acid released enzymatically from wheat bran was investigated by using resting cells of Pseudomonas fluorescens strain BF13-1p4 carrying an insertional inactivation of vdh gene and ech and fcs BF13 genes on a low copy number plasmid. Process parameters were optimized both for the biomass production phase and the bioconversion phase using food-grade ferulic acid as substrate and the approach of changing one variable while fixing the others at a certain level followed by the response surface methodology (RSM). Under optimized conditions, vanillin up to 8.46 mM (1.4 g/L) was achieved, whereas highest productivity was 0.53 mmoles vanillin L-1 h-1). Cocktails of a number of commercial enzyme (amylases, xylanases, proteases, feruloyl esterases) combined with bran pre-treatment with steam explosion and instant controlled pressure drop technology were then tested for the release of ferulic acid from wheat bran. The highest ferulic acid release was limited to 15-20 % of the ferulic acid occurring in bran, depending on the treatment conditions. Ferulic acid 1 mM in enzymatic hydrolyzates could be bioconverted into vanillin with molar yield (55.1%) and selectivity (68%) comparable to those obtained with food-grade ferulic acid after purification from reducing sugars with a non polar adsorption resin. Further improvement of ferulic acid recovery from wheat bran is however required to make more attractive the production of natural vanillin from this by-product.

The growing interest in environmental protection has led to the development of emerging biotechnologies for environmental remediation also introducing the biorefinery concept. This work mainly aimed to evaluate the applicability of innovative biotechnologies for environmental remediation and bioenergy production, throught fermentative processes. The investigated biotechnologies for waste and wastewater treatment and for the valorisation of specific feedstocks and energy recovery, were mainly focused on four research lines. 1. Biotechnology for textile wastewater treatment and water reuse that involving anaerobic and aerobic processes in combination with membrane technologies. Combinations of different treatments were also implemented for water reuse in a textile company. 2. Biotechnology for the treatment of solid waste and leachate in landfill and for biogas production. Landfill operated as Bioreactor with recirculation of the generated leachate was proposed for organic matter biostabilisation and for ammonia removal from leachate by favouring the Anammox process. 3. An innovative two-stage anaerobic process for effective codigestion of waste from the dairy industry, as cheese whey and dairy manure, was studied by combining conventional fermentative processes with a simplified system design for enhancing biomethanisation. 4) The valorisation of the glycerol waste as surplus by-product of the biodiesel industry was investigated via microbial conversion to value-added chemicals, as 1,3-propanediol. The investigated fermentative processes have been successfully implemented and reached high yields of the produced bio-chemical. The studied biotechnological systems proved to be feasible for environmental remediation and bioenergy and chemicals production.

Il siero di latte e la scotta sono effluenti provenienti rispettivamente dal processo di trasformazione del latte in formaggio e ricotta. Il siero di latte contiene minerali, lipidi, lattosio e proteine; la scotta contiene principalmente lattosio. Il siero può essere riutilizzato in diversi modi, come l'estrazione di proteine o per l’alimentazione animale, mentre la scotta è considerata solamente un rifiuto. Inoltre, a causa degli ingenti volumi di siero prodotti nel mondo, vengono a crearsi seri problemi ambientali e di smaltimento. Destinazioni alternative di questi effluenti, come le trasformazioni biotecnologiche, possono essere un modo per raggiungere il duplice obiettivo di migliorare il valore aggiunto dei processi agroindustriali e di ridurre il loro impatto ambientale. In questo lavoro sono state studiate le condizioni migliori per produrre bioetanolo dal lattosio del siero e della scotta. Kluyveromyces marxianus è stato scelto come lievito lattosio-fermentante. Sono state effettuate fermentazioni su scala di laboratorio aerobiche e anaerobiche in batch, fermentazioni semicontinue in fase dispersa e con cellule immobilizzate in alginato di calcio,. Diverse temperature sono state testate per migliorare la produzione di etanolo. Le migliori prestazioni, per entrambe le matrici, sono state raggiunte a basse temperature (28°C). Anche le alte temperature sono compatibili con buone rese di etanolo nelle fermentazioni con siero. Ottimi risultati si sono ottenuti anche con la scotta a 37°C e a 28°C. Le fermentazioni semicontinue in fase dispersa danno le migliori produzioni di etanolo, in particolare con la scotta. Invece, l'uso di cellule di lievito intrappolate in alginato di calcio non ha migliorato i risultati di processo. In conclusione, entrambi gli effluenti possono essere considerati adatti per la produzione di etanolo. Le buone rese ottenute dalla scotta permettono di trasformare questo rifiuto in una risorsa., Whey and scotta are effluents coming from cheese and ricotta processing respectively. Whey contains minerals, lipids, lactose and proteins; scotta contains mainly lactose. Whey can be reused by several ways, such as protein extraction or animal feeding, while nowadays scotta is just considered a waste; moreover, due to very high volumes of whey produced in the world, it poses serious environmental problems for disposal. Alternative destinations of these effluents, such as biotechnological transformations, can be a way to reach both goals of improving the added value of agroindustrial processes and reducing their environmental impact. In this work we investigated the way to produce bioethanol from lactose of whey and scotta and to optimize the fermentation yields. Kluyveromyces marxianus var. marxianus was chosen as lactose-fermenting yeast. Batch aerobic and anaerobic fermentations and semicontinuous fermentations in dispersed phase and in immobilized phase were carried out of whey, scotta at a laboratory scale. Different temperatures were also tested in order to try to improve the ethanol production. The best performances for both matrices were reached at low temperatures (28°C). High temperatures are also compatible with good ethanol yields in whey fermentations. Very good results are also obtained with scotta at 37°C and at 28°C. Semicontinuous fermentations in dispersed phase gave the best fermentation performances, in particular with scotta. Instead, the use of yeast cells entrapped in calcium alginate did not improve the process results. Then both effluents can be considered suitable for ethanol production. The good yields obtained from scotta allow to transform this waste in a source.

The growing interest in environmental protection has led to the development of emerging biotechnologies for environmental remediation also introducing the biorefinery concept. This work mainly aimed to evaluate the applicability of innovative biotechnologies for environmental remediation and bioenergy production, throught fermentative processes. The investigated biotechnologies for waste and wastewater treatment and for the valorisation of specific feedstocks and energy recovery, were mainly focused on four research lines. 1. Biotechnology for textile wastewater treatment and water reuse that involving anaerobic and aerobic processes in combination with membrane technologies. Combinations of different treatments were also implemented for water reuse in a textile company. 2. Biotechnology for the treatment of solid waste and leachate in landfill and for biogas production. Landfill operated as Bioreactor with recirculation of the generated leachate was proposed for organic matter biostabilisation and for ammonia removal from leachate by favouring the Anammox process. 3. An innovative two-stage anaerobic process for effective codigestion of waste from the dairy industry, as cheese whey and dairy manure, was studied by combining conventional fermentative processes with a simplified system design for enhancing biomethanisation. 4) The valorisation of the glycerol waste as surplus by-product of the biodiesel industry was investigated via microbial conversion to value-added chemicals, as 1,3-propanediol. The investigated fermentative processes have been successfully implemented and reached high yields of the produced bio-chemical. The studied biotechnological systems proved to be feasible for environmental remediation and bioenergy and chemicals production.

Il siero di latte e la scotta sono effluenti provenienti rispettivamente dal processo di trasformazione del latte in formaggio e ricotta. Il siero di latte contiene minerali, lipidi, lattosio e proteine; la scotta contiene principalmente lattosio. Il siero può essere riutilizzato in diversi modi, come l'estrazione di proteine o per l’alimentazione animale, mentre la scotta è considerata solamente un rifiuto. Inoltre, a causa degli ingenti volumi di siero prodotti nel mondo, vengono a crearsi seri problemi ambientali e di smaltimento. Destinazioni alternative di questi effluenti, come le trasformazioni biotecnologiche, possono essere un modo per raggiungere il duplice obiettivo di migliorare il valore aggiunto dei processi agroindustriali e di ridurre il loro impatto ambientale. In questo lavoro sono state studiate le condizioni migliori per produrre bioetanolo dal lattosio del siero e della scotta. Kluyveromyces marxianus è stato scelto come lievito lattosio-fermentante. Sono state effettuate fermentazioni su scala di laboratorio aerobiche e anaerobiche in batch, fermentazioni semicontinue in fase dispersa e con cellule immobilizzate in alginato di calcio,. Diverse temperature sono state testate per migliorare la produzione di etanolo. Le migliori prestazioni, per entrambe le matrici, sono state raggiunte a basse temperature (28°C). Anche le alte temperature sono compatibili con buone rese di etanolo nelle fermentazioni con siero. Ottimi risultati si sono ottenuti anche con la scotta a 37°C e a 28°C. Le fermentazioni semicontinue in fase dispersa danno le migliori produzioni di etanolo, in particolare con la scotta. Invece, l'uso di cellule di lievito intrappolate in alginato di calcio non ha migliorato i risultati di processo. In conclusione, entrambi gli effluenti possono essere considerati adatti per la produzione di etanolo. Le buone rese ottenute dalla scotta permettono di trasformare questo rifiuto in una risorsa., Whey and scotta are effluents coming from cheese and ricotta processing respectively. Whey contains minerals, lipids, lactose and proteins; scotta contains mainly lactose. Whey can be reused by several ways, such as protein extraction or animal feeding, while nowadays scotta is just considered a waste; moreover, due to very high volumes of whey produced in the world, it poses serious environmental problems for disposal. Alternative destinations of these effluents, such as biotechnological transformations, can be a way to reach both goals of improving the added value of agroindustrial processes and reducing their environmental impact. In this work we investigated the way to produce bioethanol from lactose of whey and scotta and to optimize the fermentation yields. Kluyveromyces marxianus var. marxianus was chosen as lactose-fermenting yeast. Batch aerobic and anaerobic fermentations and semicontinuous fermentations in dispersed phase and in immobilized phase were carried out of whey, scotta at a laboratory scale. Different temperatures were also tested in order to try to improve the ethanol production. The best performances for both matrices were reached at low temperatures (28°C). High temperatures are also compatible with good ethanol yields in whey fermentations. Very good results are also obtained with scotta at 37°C and at 28°C. Semicontinuous fermentations in dispersed phase gave the best fermentation performances, in particular with scotta. Instead, the use of yeast cells entrapped in calcium alginate did not improve the process results. Then both effluents can be considered suitable for ethanol production. The good yields obtained from scotta allow to transform this waste in a source.

Bioconversion of ferulic acid to vanillin represents an attractive opportunity for replacing synthetic vanillin with a bio-based product, that can be label “natural”, according to current food regulations. Ferulic acid is an abundant phenolic compound in cereals processing by-products, such as wheat bran, where it is linked to the cell wall constituents. In this work, the possibility of producing vanillin from ferulic acid released enzymatically from wheat bran was investigated by using resting cells of Pseudomonas fluorescens strain BF13-1p4 carrying an insertional inactivation of vdh gene and ech and fcs BF13 genes on a low copy number plasmid. Process parameters were optimized both for the biomass production phase and the bioconversion phase using food-grade ferulic acid as substrate and the approach of changing one variable while fixing the others at a certain level followed by the response surface methodology (RSM). Under optimized conditions, vanillin up to 8.46 mM (1.4 g/L) was achieved, whereas highest productivity was 0.53 mmoles vanillin L-1 h-1). Cocktails of a number of commercial enzyme (amylases, xylanases, proteases, feruloyl esterases) combined with bran pre-treatment with steam explosion and instant controlled pressure drop technology were then tested for the release of ferulic acid from wheat bran. The highest ferulic acid release was limited to 15-20 % of the ferulic acid occurring in bran, depending on the treatment conditions. Ferulic acid 1 mM in enzymatic hydrolyzates could be bioconverted into vanillin with molar yield (55.1%) and selectivity (68%) comparable to those obtained with food-grade ferulic acid after purification from reducing sugars with a non polar adsorption resin. Further improvement of ferulic acid recovery from wheat bran is however required to make more attractive the production of natural vanillin from this by-product.

Copolymers of poly(butylene succinate) (PBS) containing thiodiethylene succinate sequences with different molecular architectures (PBSPTDGS) were prepared via reactive blending in the presence of a Ti-based catalyst. In particular, a block copolymer with long sequences and a random one have been investigated for their biodegradability. The parent homopolymer PBS has been also synthesized via the usual two-stage melt polycondensation and used as reference polymer in the study. The hydrolitic treatment carried out using lipase from Candida cylindracea ([E] = 50 U/ml, T = 30 °C and pH = 7.0), showed that copolymers biodegraded more rapidly and extensively than PBS. ATRIR analysis and DSC measurements also performed on the resulting samples showed that the enzyme simultaneously attacks the amorphous phase and the PTDGS crystalline phase, which is characterized by lower packing density and degree of perfection with respect to the PBS one. This result suggested that the higher degradability of the copolymers under study can be correlated both to the crystallinity degree and to the nature of the crystalline phase. NMR analysis, performed to detect changes in composition of the copolymers during the degradation, demonstrated that enzyme hydrolysis preferentially targeted ester groups of TDGS sequences because of their higher hydrophilicity. © 2013 Elsevier Ltd. All rights reserved.

Mediterranean Sea is facing a very high risk of oil pollution due to the high number of oil extractive and refining sites along the basin coasts, and the intense maritime traffic of oil tankers. All the Mediterranean countries have adopted severe regulations for minimizing pollution events and bioremediation feasibility studies for the most urgent polluted sites are undergoing. However, the analysis of the scientific studies applying modern 'meta-omics' technologies that have been performed on marine oil pollution worldwide showed that the Southern Mediterranean side has been neglected by the international research. Most of the studies in the Mediterranean Sea have been done in polluted sites of the Northern side of the basin. Those of the Southern side are poorly studied, despite many of the Southern countries being major oil producers and exporters. The recently EU-funded research project ULIXES has as a major objective to increase the knowledge of the bioremediation potential of sites from the Southern Mediterranean countries. ULIXES is targeting four major polluted sites on the coastlines of Egypt, Jordan, Morocco and Tunisia, including seashore sands, lagoons, and oil refinery polluted sediments. The research is designed to unravel, categorize, catalogue, exploit and manage the diversity and ecology of microorganisms thriving in these polluted sites. Isolation of novel hydrocarbon degrading microbes and a series of state of the art 'meta-omics' technologies are the baseline tools for improving our knowledge on biodegradation capacities mediated by microbes under different environmental settings and for designing novel site-tailored bioremediation approaches. A network of twelve European and Southern Mediterranean partners is cooperating for plugging the existing gap of knowledge for the development of novel bioremediation processes targeting such poorly investigated polluted sites.

Biological invasion is widely studied, however, conclusions on the outcome of this process mainly originate from observations in systems that leave a large number of experimental variables uncontrolled. Here using a fully controlled system consisting of assembled bacterial communities, we evaluate the degree of invasion and the effect on the community functionality in relation to the initial community evenness under specific environmental stressors. We show that evenness influences the level of invasion and that the introduced species can promote functionality under stress. The evenness-invasibility relationship is negative in the absence and neutral in the presence of stress. Under these conditions, the introduced species is able to maintain the functionality of uneven communities. These results indicate that communities, initially having the same genetic background, in the presence of the same invader, react in a different way with respect to invasibility and functionality depending on specific environmental conditions and community evenness.

Enzyveba, a partially characterized complex consortium of not-adapted microorganisms developed through prolonged stabilization of organic wastes, was found to markedly intensify the aerobic remediation of aged PAH- and PCB-contaminated soil by acting as a source of exogenous specialized microorganisms and nutrients. Thus, Enzyveba was tested in the bioremediation of Diesel (G1) and HiQ Diesel (G2) contaminated soils under aerobic slurry-phase conditions by means of a chemical, microbiological, ecotoxicological integrated analytical procedure. The addition of Enzyveba resulted in a higher availability of cultivable specialized bacteria and fungi but this resulted in a slight intensification of soil remediation, probably because of the high content of nutrients and specialized microorganisms of the soil. In many cases, the biotreatability of soils impacted by diesel fuel is limited by their poor content of autochthonous pollutant-degrading microorganisms. Thus, bioaugmentation with stable and reproducible cultures with the required broad substrate specificity might be the solution for a successful remediation. Two microbial consortia, ENZ-G1 and ENZ-G2, were enriched from Enzyveba on G1 and G2. Both consortia consist of a similar composition of bacterial and fungal species. They exhibited a comparable and significant biodegradation capability by removing about 90% of 1 g/l of diesel fuel under liquid culture conditions. Given their remarkable biodegradation potential, richness of quite diverse microbes, stability and resistance after cryopreservation at -20 °C for several months, both consortia appear very interesting candidates for bioaugmentation on site. The mycoflora of a soil historically contaminated by high concentration of PCBs was characterised before, at the beginning and at the end of the biotreatment mentioned above. Several mitosporic fungi isolated from soil grew in presence of a mixture of three PCBs congeners when also glucose was provided. This is the

An anaerobic consortium, capable of efficiently converting into methane the organic fraction of mechanically sorted municipal solid waste (MS-OFMSW), was obtained through a dedicated enrichment procedure in a 0.36 L up-flow anaerobic recirculated reactor. This result was obtained after several micro-reactor fed-batch procedures that allowed to obtain only a few methanization of the MS-OFMSW.

Enzyveba, a partially characterized complex consortium of not-adapted microorganisms developed through prolonged stabilization of organic wastes, was found to markedly intensify the aerobic remediation of aged PAH- and PCB-contaminated soil by acting as a source of exogenous specialized microorganisms and nutrients. Thus, Enzyveba was tested in the bioremediation of Diesel (G1) and HiQ Diesel (G2) contaminated soils under aerobic slurry-phase conditions by means of a chemical, microbiological, ecotoxicological integrated analytical procedure. The addition of Enzyveba resulted in a higher availability of cultivable specialized bacteria and fungi but this resulted in a slight intensification of soil remediation, probably because of the high content of nutrients and specialized microorganisms of the soil. In many cases, the biotreatability of soils impacted by diesel fuel is limited by their poor content of autochthonous pollutant-degrading microorganisms. Thus, bioaugmentation with stable and reproducible cultures with the required broad substrate specificity might be the solution for a successful remediation. Two microbial consortia, ENZ-G1 and ENZ-G2, were enriched from Enzyveba on G1 and G2. Both consortia consist of a similar composition of bacterial and fungal species. They exhibited a comparable and significant biodegradation capability by removing about 90% of 1 g/l of diesel fuel under liquid culture conditions. Given their remarkable biodegradation potential, richness of quite diverse microbes, stability and resistance after cryopreservation at -20 °C for several months, both consortia appear very interesting candidates for bioaugmentation on site. The mycoflora of a soil historically contaminated by high concentration of PCBs was characterised before, at the beginning and at the end of the biotreatment mentioned above. Several mitosporic fungi isolated from soil grew in presence of a mixture of three PCBs congeners when also glucose was provided. This is the

The hydrogen production in the green microalga Chlamydomonas reinhardtii was evaluated by means of a detailed physiological and biotechnological study. First, a wide screening of the hydrogen productivity was done on 22 strains of C. reinhardtii, most of which mutated at the level of the D1 protein. The screening revealed for the first time that mutations upon the D1 protein may result on an increased hydrogen production. Indeed, productions ranged between 0 and more than 500 mL hydrogen per liter of culture (Torzillo, Scoma et al., 2007a), the highest producer (L159I-N230Y) being up to 5 times more performant than the strain cc124 widely adopted in literature (Torzillo, Scoma, et al., 2007b). Improved productivities by D1 protein mutants were generally a result of high photosynthetic capabilities counteracted by high respiration rates. Optimization of culture conditions were addressed according to the results of the physiological study of selected strains. In a first step, the photobioreactor (PBR) was provided with a multiple-impeller stirring system designed, developed and tested by us, using the strain cc124. It was found that the impeller system was effectively able to induce regular and turbulent mixing, which led to improved photosynthetic yields by means of light/dark cycles. Moreover, improved mixing regime sustained higher respiration rates, compared to what obtained with the commonly used stir bar mixing system. As far as the results of the initial screening phase are considered, both these factors are relevant to the hydrogen production. Indeed, very high energy conversion efficiencies (light to hydrogen) were obtained with the impeller device, prooving that our PBR was a good tool to both improve and study photosynthetic processes (Giannelli, Scoma et al., 2009). In the second part of the optimization, an accurate analysis of all the positive features of the high performance strain L159I-N230Y pointed out, respect to the WT, it has: (1) a larger chlorop

The hydrogen production in the green microalga Chlamydomonas reinhardtii was evaluated by means of a detailed physiological and biotechnological study. First, a wide screening of the hydrogen productivity was done on 22 strains of C. reinhardtii, most of which mutated at the level of the D1 protein. The screening revealed for the first time that mutations upon the D1 protein may result on an increased hydrogen production. Indeed, productions ranged between 0 and more than 500 mL hydrogen per liter of culture (Torzillo, Scoma et al., 2007a), the highest producer (L159I-N230Y) being up to 5 times more performant than the strain cc124 widely adopted in literature (Torzillo, Scoma, et al., 2007b). Improved productivities by D1 protein mutants were generally a result of high photosynthetic capabilities counteracted by high respiration rates. Optimization of culture conditions were addressed according to the results of the physiological study of selected strains. In a first step, the photobioreactor (PBR) was provided with a multiple-impeller stirring system designed, developed and tested by us, using the strain cc124. It was found that the impeller system was effectively able to induce regular and turbulent mixing, which led to improved photosynthetic yields by means of light/dark cycles. Moreover, improved mixing regime sustained higher respiration rates, compared to what obtained with the commonly used stir bar mixing system. As far as the results of the initial screening phase are considered, both these factors are relevant to the hydrogen production. Indeed, very high energy conversion efficiencies (light to hydrogen) were obtained with the impeller device, prooving that our PBR was a good tool to both improve and study photosynthetic processes (Giannelli, Scoma et al., 2009). In the second part of the optimization, an accurate analysis of all the positive features of the high performance strain L159I-N230Y pointed out, respect to the WT, it has: (1) a larger chlorop

Some bacterial strains were isolated after soil enrichments in the presence of chrysene as the sole carbon and energy source. The soil was collected from a petrochemical company site in Halong Bay, Vietnam. One of the chrysene enriched microbes was found to be a Paracoccus sp. In liquid cultures containing chrysene or pyrene as the sole energy and carbon source at the initial concentration of 200 mg l-1, this bacterium was able to degrade 80% and 77% respectively of the target compounds in 15 days. In order to test the efficiency of the Paracoccus strain in the bioremediation of soil polluted with polycyclic aromatic hydrocarbons (PAHs), experiments with soil slurry reactors were carried out on a well-characterized Italian pristine soil spiked with equal parts of phenanthrene, fluoranthene and pyrene to a final concentration of 2000 mg of total PAHs per kg of dry soil. The monitoring of the residual concentration of the PAHs demonstrated total removal of these contaminants over a period of 70 days.

A large array of microbial processes are taking place in aerobic or subsurface anaerobic sediments, where they are responsible for the turnover of naturally occurring organic matter and the N, P, S geochemical cycles (Kafkewitz and Togna, 1998). Oxidizing conditions generally exist only at the top few centimeters of surface sediments, providing a limited zone where oxygen is available as electron acceptor for aerobic biotransformation of organic and inorganic chemical compounds. Beneath the aerobic zone, sediments are typically dominated by a single electron acceptor process such as sulfate-reduction in marine sediments or methanogenesis in freshwater sediments. Bacteria and eukaryotic organisms are coexisting in such matrices, by strictly interacting and cooperating through complex and often not fully elucidated mechanisms. The microbial population might be responsible for the biodegradation/biotransformation of several chlorinated priority pollutants, such polychlorinated-biphenyls, - dibenzodioxins, -dibenzofurans, -phenols and -benzenes, as well as some hydrocarbons, in particular under anaerobic conditions. Under sulfidogenic conditions, it might be also responsible for the precipitation/immobilization of some toxic heavy metals (Lloyd and Lovley, 2001). These microbial processes might be in turn responsible for a significant and cost effective decontamination/detoxification of polluted sediments (Bedard and Quensen, 1995; Lloyd and Lovley, 2001; Haggblom et al., 2003). This potential becomes of special relevance when they are actively taking place in situ, where they might contribute to a significant mitigation of contamination (Natural Attenuation, NA) (Apitz et al., 2004). NA often results in a significant reduction of the area (volume of contaminated sediment) to be dredged or managed through suitable in situ physicalchemical treatments.

Various approaches to clean contaminated aquatic environments have been proposed. In recent years, natural attenuation has received increasing attention and it is generally accepted that microorganisms are the principal mediators of the natural attenuation of many pollutants. However, the complexity of environmental systems such as sediments requires a multifaceted approach to understand microbial processes and their potential. This is even more so under in situ conditions, where the activity of pollutant degrading microorganisms is generally slow, partial and constrained spatially and/or temporally. Recent developments in molecular biology and genomics are offering tools to explore microbial processes at a level that encompasses the genetic characteristics of the local microbial players, culturable or not, as well as their organization into complex communities and their interactions both with each other and with the target chemicals. It is now possible to study microbes directly in their environments at the population level as well as at the single cell level and to link biology to geochemistry. Integrative knowledge from culture-independent studies based on functional characters and assessment of the diversity and quantity of catabolic genes in response to pollution, will allow a deeper understanding of and a rational intervention in environmental processes. Moreover, the use of genomic libraries to retrieve genes from natural bacterial communities without cultivation will allow a breakthrough in accessing new microbial capabilities. In this chapter, the main features, advantages and limitations of these innovative approaches to the biomonitoring and analysis of intrinsic bioremediation potential of polluted environments and sediments are critically reviewed. Then, the potential of the same strategies in the integrated chemical, physical and biological monitoring and characterization of polluted sediments subjected to natural decontamination is shown through the d

Increasing urbanization, industrialization and over population cause fast and considerable degradation of soil and vegetation cover, which necessitate pursuing the methods of managing derelict industrial lands. On such chemically devastated lands vegetation plays increasingly important ecological and sanitary role. Proper management of plants from such areas may significantly contribute to restoring the natural environment. Numerous efforts have been undertaken recently to find methods of cleaning up soils contaminated by xenobiotic compounds, such as phytoremediation. The aim of this thesis work is to analyse the influence of heavy metals and organic contaminants of soil on the growth yield and content of pollutants in Cannabis sativa L. This plant was selected because a) it grows rapidly, reaching full harvest in just 100-120 days (depending on local conditions) and produces a sphere of roots that extends from 1.5 to 2.5 meters into the soil, without requiring nutrients, herbicides and pesticides; b) it is a non-food crop, suitable for the production of a wide variety of renewable products more efficiently than what can be done with other non-food crops; and c) it produces components with relevant market opportunities through a stepwise breakdown. Hemp biomass can be used for the preparation of several commercial items, including paper, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food, and animal feed. However, hemp presents a key disadvantage: it is also used as an illegal narcotics and often that costs discriminates between fiber types and drug type use of hemp crop. Consequently, only cultivars which set seed in a given member state are permitted to be grown in the EU.

Microalgae cultures are attracting great attentions in many industrial applications. However, one of the technical challenges is to cut down the capital and operational costs of microalgae production systems, with special difficulty in reactor design and scale-up. The thesis work open with an overview on the microalgae cultures as a possible answer to solve some of the upcoming planet issues and their applications in several fields. After the work offers a general outline on the state of the art of microalgae culture systems, taking a special look to the enclosed photobioreactors (PBRs). The overall objective of this study is to advance the knowledge of PBRs design and lead to innovative large scale processes of microalgae cultivation. An airlift flat panel photobioreactor was designed, modeled and experimentally characterized. The gas holdup, liquid flow velocity and oxygen mass transfer of the reactor were experimentally determined and mathematically modeled, and the performance of the reactor was tested by cultivation of microalgae. The model predicted data correlated well with experimental data, and the high concentration of suspension cell culture could be achieved with controlled conditions. The reactor was inoculated with the algal strain Scenedesmus obliquus sp. first and with Chlorella sp. later and sparged with air. The reactor was operated in batch mode and daily monitored for pH, temperature, and biomass concentration and activity. The productivity of the novel device was determined, suggesting the proposed design can be effectively and economically used in carbon dioxide mitigation technologies and in the production of algal biomass for biofuel and other bioproducts. Those research results favored the possibility of scaling the reactor up into industrial scales based on the models employed, and the potential advantages and disadvantages were discussed for this novel industrial design.

Introduction 1.1 Occurrence of polycyclic aromatic hydrocarbons (PAH) in the environment Worldwide industrial and agricultural developments have released a large number of natural and synthetic hazardous compounds into the environment due to careless waste disposal, illegal waste dumping and accidental spills. As a result, there are numerous sites in the world that require cleanup of soils and groundwater. Polycyclic aromatic hydrocarbons (PAHs) are one of the major groups of these contaminants (Da Silva et al., 2003). PAHs constitute a diverse class of organic compounds consisting of two or more aromatic rings with various structural configurations (Prabhu and Phale, 2003). Being a derivative of benzene, PAHs are thermodynamically stable. In addition, these chemicals tend to adhere to particle surfaces, such as soils, because of their low water solubility and strong hydrophobicity, and this results in greater persistence under natural conditions. This persistence coupled with their potential carcinogenicity makes PAHs problematic environmental contaminants (Cerniglia, 1992; Sutherland, 1992). PAHs are widely found in high concentrations at many industrial sites, particularly those associated with petroleum, gas production and wood preserving industries (Wilson and Jones, 1993). 1.2 Remediation technologies Conventional techniques used for the remediation of soil polluted with organic contaminants include excavation of the contaminated soil and disposal to a landfill or capping - containment - of the contaminated areas of a site. These methods have some drawbacks. The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. The cap and containment method is only an interim solution since the contamination remains on site, requiring monitoring and

Polycyclic aromatic hydrocarbons are chemicals produced by both human activities and natural sources and they have been present in the biosphere since millions of years. For this reason microorganisms should have developed, during the world history, the capacity of metabolized them under different electron acceptors and redox conditions. The deep understanding of these natural attenuation processes and of microbial degradation pathways has a main importance in the cleanup of contaminated areas. Anaerobic degradation of aromatic hydrocarbons is often presumed to be slow and of a minor ecological significance compared with the aerobic processes; however anaerobic bioremediation may play a key role in the transformation of organic pollutants when oxygen demand exceeds supply in natural environments. Under such conditions, anoxic and anaerobic degradation mediated by denitrifying or sulphate-reducing bacteria can become a key pathway for the contaminated lands clean up. Actually not much is known about anaerobic bioremediation processes. Anaerobic biodegrading techniques may be really interesting for the future, because they give the possibility of treating contaminated soil directly in their natural status, decreasing the costs concerning the oxygen supply, which usually are the highest ones, and about soil excavations and transports in appropriate sites for a further disposal. The aim of this dissertation work is to characterize the conditions favouring the anaerobic degradation of polycyclic aromatic hydrocarbons. Special focus will be given to the assessment of the various AEA efficiency, the characterization of degradation performance and rates under different redox conditions as well as toxicity monitoring. A comparison with aerobic and anaerobic degradation concerning the same contaminated material is also made to estimate the different biodegradation times.

I policlorobifenili (PCB) sono un gruppo di 209 congeneri di bifenili policlorurati altamente tossici e persistenti che, a causa della loro elevata lipofilia, tendono ad accumularsi in sedimenti anaerobici marini, tramite i quali possono entrare nella catena alimentare. I PCB possono essere degradati mediante processi di declorurazione riduttiva mediati da popolazioni microbiche anaerobiche in grado di utilizzarli fortuitamente come accettori finali della catena respiratoria. Il processo consiste quindi nella bioconversione di congeneri ad alto grado di clorurazione in PCB basso clorurati, meno tossici, meno bioaccumulabili e più facilmente biodegradabili in condizioni aerobiche. Nel presente elaborato è stata investigata la capacità di una popolazione microbica arricchita su congeneri coplanari di PCB da un sedimento contaminato del Canale Brentella (Prima Zona Industriale di Porto Marghera, laguna di Venezia), di declorurare miscele commerciali di PCB (Aroclor 1254) in condizioni geobiochimiche di laboratorio che riproducono quelle presenti in sito. Il processo è quindi stato studiato in microcosmi anaerobici slurry di sedimento sospeso nella stessa acqua del sito e monitorato con un approccio chimico e microbiologico integrato. Ai fini di caratterizzare e stimolare i microganismi responsabili del processo degradativo sono state utilizzate tecniche convenzionali basate sull’inibizione selettiva di diversi gruppi microbici. Dopo una fase di latenza di 7 settimane, la coltura microbica ha declorurato velocemente ed estesamente la miscela commerciale di PCB saggiata, bioconvertendo il 70% dei congeneri ad alto grado di clorurazione (da penta- a octa- clorurati) in PCB di- e tri-clorurati. Il processo ha esibito selettività nei confronti delle posizioni meta dei gruppi 2,3- e 2,3,4-clorofenile e para dei gruppi 3,4- e 3,4,5-clorofenile, secondo il modello di declorurazione H’. Il monitoraggio delle attività microbiche in presenza dei diversi inibitori saggiati ha perm

Le acque di vegetazione (AV) costituiscono un serio problema di carattere ambientale, sia a causa della loro elevata produzione sia per l’ elevato contenuto di COD che oscilla fra 50 e 150 g/l. Le AV sono considerate un refluo a tasso inquinante fra i più elevati nell’ambito dell’industria agroalimentare e la loro tossicità è determinata in massima parte dalla componente fenolica. Il presente lavoro si propone di studiare e ottimizzare un processo non solo di smaltimento di tale refluo ma anche di una sua valorizzazione, utlizzandolo come materia prima per la produzione di acidi grassi e quindi di PHA, polimeri biodegradabili utilizzabili in varie applicazioni. A tale scopo sono stati utilizzati due bioreattori anaerobici a biomassa adesa, di identica configurazione, con cui si sono condotti due esperimenti in continuo a diverse temperature e carichi organici al fine di studiare l’influenza di tali parametri sul processo. Il primo esperimento è stato condotto a 35°C e carico organico pari a 12,39 g/Ld, il secondo a 25°C e carico organico pari a 8,40 g/Ld. Si è scelto di allestire e mettere in opera un processo a cellule immobilizzate in quanto questa tecnologia si è rivelata vantaggiosa nel trattamento continuo di reflui ad alto contenuto di COD e carichi variabili. Inoltre si è scelto di lavorare in continuo poiché tale condizione, per debiti tempi di ritenzione idraulica, consente di minimizzare la metanogenesi, mediata da microrganismi con basse velocità specifiche di crescita. Per costituire il letto fisso dei due reattori si sono utilizzati due diversi tipi di supporto, in modo da poter studiare anche l’influenza di tale parametro, in particolare si è fatto uso di carbone attivo granulare (GAC) e filtri ceramici Vukopor S10 (VS). Confrontando i risultati si è visto che la massima quantità di VFA prodotta nell’ambito del presente studio si ha nel VS mantenuto a 25°C: in tale condizione si arriva infatti ad un valore di VFA prodotti pari a 524,668 mgCOD/L. Inol