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Dottorato di Ricerca in Scienze ed Ingegneria dell'Ambiente, delle Costruzioni e dell'Energia. Ciclo XXIX The treatment of wastewater and its reuse is a very important topic in industrial processes. This because not only avoids drawing on natural resources, but also enables a significant reduction in the amount of wastewater discharged into the natural environment. Wastewater can also be used for various purposes where drinking water quality is not mandatory, including agricultural irrigation, the cleaning of industrial equipment, the watering of green spaces, and street maintenance, etc. In fact, the water reuse has become essential in all areas in the world that suffer from water shortages [1]. Different methods are used for wastewater treatment. These processes can be to divide in: primary, secondary and tertiary treatment. Primary treatment (screening, filtration, centrifugation, sedimentation, coagulation, gravity and flotation method) includes preliminary purification processes of a physical and chemical nature while secondary treatment deals with the biological treatment of wastewater. In tertiary treatment process wastewater is converted into good quality water that can be used for different types of purpose, i.e. drinking, industrial, medicinal etc. supplies [2]. The complexity of industrial processes, the variety of pollutants and the limitation of a single operation, has led to the need for more complex processes and especially to a combination of processes. Membranes technologies falls on the tertiary water treatment technologies and are actually the most effective separation processes and they are still in rapid development creating new prospects of their applications in clean technologies [3]. The utilization of membrane operations as hybrid systems, i.e. in combination with other conventional techniques or integrated with different membrane operations is considered the way forward for more rationale applications [4]. The possibilities of redesigning various industrial cycles by combining various membrane operations have been studies and in some case realized with a low environmental impact and a low energy consumption [5]. Different processes can be used in various steps of a hybrid system, depending from the size of the pollutants to be removed. Microfiltration (MF) and ultrafiltration (UF) membrane processes, can be used as pre-treatment, while nanofiltration (NF) and reverse osmosis (RO) can used in the final step of the integrated system to remove particles with smaller dimensions (Chapter 1) The membranes have different morphological characteristics that affect their performance. The study of all the conditions which modulate these characteristics is a crucial point in the choice of membranes to be used in the various separation processes. Therefore, it is important to investigate about new materials and new types of membranes, like as mixed matrix membrane (MMM). MMM is a heterogeneous membrane consisting of inorganic fillers embedded in a polymeric matrix and can be made into flat sheets and hollow-fiber. Nevertheless, the selection of membrane configuration is greatly dependent on the application and therefore the production of MMMs in useful configuration is undoubtedly a crucial point in membrane development [6]. Also, the selection of inorganic fillers depends of desired membrane performance and their use. More attention was focus on the interesting characteristic of carbonanotubes (CNTs) (chapter 2). CNTs themselves have remarkable electrical, thermal, and mechanical properties. These nanotubes have the structure of a rolled-up graphene sheet with smaller diameter. Multiwalled carbonanotube (MWCNTs) were used to prepare MMMs for wastewater treatment. Different compounds, as additives in the polymeric membranes were used in high percentage; in the case of MWCNTs was observed as a low amount can change the membrane morphologies, mechanical and transport properties. A crucial point was the choice of membrane materials. Two type, hydrophilic poly(imide) (PI) and hydrophobic poly(vinylidenfluoride) (PVDF) were choose for membrane materials to produce MMMs. Another important point in this study was the use of functionalized MWCNTs that provide a good dispersion in the casting solution first, and in the polymeric matrix after phase separation. The main limitation in the use of CNTs is their poor dispersion in the main solvents used for the preparation of membranes. The functionalization has been proven an efficient method to overcome this limitation improving the compatibility with the polymer matrix. The presence of polar groups on the carbon nanotubes can reduces their tendency to aggregate by van der Waals interactions, while forming hydrogen bonds and electron donor/acceptor interactions with the polymer. Low percentages of CNTs were used for the preparation of membranes. These percentages were sufficient to improve better performance to modified membranes. PI was select as polymeric materials because combine easy processability in the form of membranes, with a high chemical and thermal stability, over a wide range of operative conditions. Three different PI polymers were used to prepared porous asymmetric membrane by non-solvent induced phase separation (NIPS): a homopolymer (Matrimid) and two co-polymers (Lenzing P84 and Torlon). The effect of membrane preparation conditions on the membrane morphology and transport properties, were investigate. Moreover, mixed matrix based on co-polyimide P84 and functionalized multiwalled carbon nanotubes (oxidized and aminated MWCNTs) were prepared. The different polymeric membranes were compared in the rejection of organic dyes, as model of organic pollutant present in wastewater (chapter 3). To investigate about the influence of functional groups on the MWCNTs for their interaction with polymeric matrix, three different type of functionalized MWCNTs (oxidized, amined and aminated) were dispersed also in polymeric hydrophobic PVDF membranes. PVDF was selected as polymeric materials of its outstanding properties: excellent chemical resistance and hydrolytic stability; high mechanical strength and stability over a broad pH range; polymorphism (main crystalline phases are: α, β, γ, δ and ε) [7]. The aim was to tailor the interactions with the polymeric matrix in order to realize high performing composite film with improved performance. Bovine serum albumin (BSA) protein was select as compound to evaluate the membrane performance. In particular, the antifouling properties and the permeation flux of mixed matrix membranes, were evaluate as well as thermal and structural and mechanical properties (chapter 4). Università della Calabria.

Le Orchidaceae è una delle famiglie di monocotiledoni più sviluppate; la loro produzione di fiori recisi e di piante da vaso hanno un elevato valore economico nel mercato florovivaistico internazionale. Ad oggi è usuale la coltura in vitro di orchidee attraverso la propagazione di Protocormi (Protocorm like bodies; PLBs), per germogli ascellari e callo. Uno degli obiettivi del miglioramento genetico nelle orchidee è quello di ottenere nuove varietà e combinazioni ibride commercialmente interessanti. I programmi d’incrocio tradizionali hanno finora portato a buoni risultati, ma i consumatori sono sempre desiderosi di avere nuove varietà e da qui la necessità di produrre sempre nuovo materiale con caratteristiche di interesse. Nel presente lavoro abbiamo focalizzato la nostra attenzione sull’introduzione di nuova variabilità genetica in Dendrobium e Phalaenopsis spp per mezzo di un approccio biotecnologico che combini le manipolazioni cellulari e molecolari per indurre nuova variabilità genetica riducendo tempi e costi del processo. Abbiamo perciò sviluppato in Dendrobium e Phalaenopsis spp i protocolli per l’isolamento protoplasti, da foglia e PLBs, e per la loro fusione per via chimica e per elettrofusione. Abbiamo utilizzato agenti antimitotici per indurre mutanti poliploidi. Per rendere questa tecnologia più efficace ed efficiente, la citometria a flusso è stata ampliamente utilizzata per separare singolarmente i prodotti di fusione e per un rapido screening dei mutanti poliploidi. Sono stati ottenuti un buon numero di mutanti poliploidi e alcuni di questi hanno mostrato fenomeni di poliploidizzazione parziale. La citometria a flusso ci ha permesso, immediatamente dopo il trattamento, di individuare la migliore condizione per l’induzione di poliploidi, permettendo di ridurre tempi e materiale per l’ottenimento dei mutanti. La citometria a flusso in combinazione con i marcatori molecolari e le analisi citogenetiche ci hanno permesso di caratterizzare ed individuare i mutanti tetraploidi e quelli parzialmente duplicati. Orchidaceae family is one of the most developed monocotyledonous group; their pot plant and cut flower production have a high economical value in the international flower market. At first, in vitro culture protocols have been developed in this family and it is now usual to propagate orchids via protocorm-like body (PLB) formation, shoot multiplication or callus culture. One of the aims of the genetic improvement in orchids is to obtain new varieties and commercially attractive hybrid combinations. So far, the traditional breeding programs have led to very good results, but consumers desires are changeable and the need exists to generate always new stocks and to include some desirable combinations not allowed due to genetic incompatibility problems. In our research work we have focused our efforts on the introduction of new genetic variability in Dendrobium and Phalaenopsis spp by means of a biotechnological approach which combines cellular and molecular manipulations to increase genetic variability. This achievement in turn should provide a clue to address these incompatibilities and to rise new genetic variability. With this in mind, we have developed in Dendrobium and Phalaenopsisspp a protocol for leaf and PLBs protoplasts isolation and somatic hybridization via PEG (Polyethylene glycol) or electrofusion. In order to obtain polyploid mutants we used cell cycle blocking agents in vitro. To make this technological approach more effective and efficient, flow cytometry has been largely applied to recognize and sort single hybridized cells from normal ones immediately after the fusion process and for a rapid screening and identification of the new polyploid mutants. We were successful in obtaining polyploidy mutants from in vitro explants; interestingly, some of them showed a downsizing genome situation exhibiting a partial polyploidy. The flow cytometry screening proved to be an usefull tool to select polyploids and to reduce cost and time consumption for the entire process. Molecular marker (RAPD and SSR) and cytogenetic approachs were also applied to differentiate orchid mutants allowing a genetic identification of controls from tetraploids and near-tetraploids,thus reducing the general efforts to grow up very large plant population of unknown ploidy. Dottorato di ricerca in Ortoflorofrutticoltura