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Questo libro contiene una raccolta di ricette della tradizione bolognese elaborato da studenti delle scuole della città.

La valutazione del rischio ambientale e alimentare hanno rappresentato un ruolo centrale nel raggiungimento degli obiettivi stabiliti dalla strategia della Commissione Europea nel programma Europa 2020 e costituiscono uno dei capisaldi dell���attuale strategia Horizon Europe. La collaborazione fra enti pubblici, societ�� scientifiche e privati rappresenta il core delle nuove strategie per raggiungere l���obiettivo della sicurezza ambientale e alimentare con un focus sulla salute, come anche indicato dalla FAO e dall���OMS. Accanto ai numerosi e stringenti controlli sulla qualit�� dei prodotti ortofrutticoli alla vendita, oltre 10000 campioni anno in Italia, esistono i controlli dei produttori e delle catene della grande distribuzione organizzata (GDO) che non sono mai pubblici. Questo report, edito dal Dipartimento di Scienze Tecnologie Agro-alimentari dell���Universit�� di Bologna, presenta proprio questi dati, in gergo chiamati ���grigi���. Questa trattazione rappresenta un primo passo, un unicum, grazie alla collaborazione tra una societ�� scientifica, il GRIFA, e una societ�� privata, Conserve Italia, che mette a disposizione milioni di dati residuali di prodotti fitosanitari in derrate alimentari in pre-raccolta per fare una valutazione statistica dell���andamento nazionale del loro utilizzo in un arco temporale molto ampio, che permetta di comprendere come l���agricoltura si sia adattata ai cambiamenti normativi, di costume e climatici. Un lavoro complesso che gli autori hanno affrontato con tenacia e dedizione, trovando la chiave scientifica per una corretta e oggettiva interpretazione.

Soil is a complex heterogeneous system whose physical, chemical and biological properties regulate interactions with the chemical species which reach its surface. Soil chemistry is an essential tool for understanding and predicting these interactions. Soil is able to immobilize and transform organic and inorganic molecules by different mechanisms, such as complexing and redox reactions. This behaviour gives soil detoxifying capacities towards pollutants which accumulate in the environment. Pollution by heavy metals is regulated by their solubility in soil solution which in turn depends on soil pH and redox properties and metal speciation. Organic and inorganic colloidal soil fractions can promote the immobilisation, degradation, and diffusion of organic molecules such as agrochemicals, solvents, hydrocarbons and other chemicals which reach the soil by anthropic activities. Predicting the fate of xenobiotics in soil, water, air, and plant ecosystems, the recycling of biomass and the decontamination of polluted soils are of major concern to soil chemistry.

A commercial electronic nose (e-nose) was used to discriminate healthy grapevine tissue from crown galled ones. Samples were collected from outdoor trials and from a nursery. Experimental samples were obtained by grapevine inoculation with Agrobacterium vitis suspensions: samples were collected after 9 months (young rootstocks) and 4 years (aged rootstocks). Field samples (1-year old shoots) were provided by Emilia Romagna Phytosanitary Service (Italy). E-nose analysis was carried out on rootstock and shoot segments. Samples were distributed in the principal component analysis score plot in two areas: on the left, healthy samples and those with small tumors were grouped, whereas high disease severity samples were localized on the right. Linear discriminant analysis correctly classified the samples with a total recognition percentage of 79%. The data obtained allowed building a database in which different sizes, organs, and disease severity of samples are taken into consideration.

Owing to their environmental diffusion and persistence, sulfonamide antibiotics (sulfa drugs) are responsible to induce high level of resistance in bacteria. The sulfonamide anionic nature makes them highly mobile along soil profile and is responsible for their accumulation into water bodies. In order to limit the diffusion of resistance determinants, it is of utmost importance to identify adsorbents for this antibiotic family to be adopted for water cleanup purpose. Three high silica zeolites (Y, MOR, ZSM-5) have been tested for their capability to extract sulfonamides from water. Kinetics, capacity and reversibility of the adsorption have been studied along with sulfonamide arrangement into the porosities of each zeolite [1-3]. The sulfa drugs irreversibly adsorbed onto zeolite Y at ca. 26% on average and with the process equilibrium reached in less than 1 min [1,3]. The favorable adsorption kinetics was confirmed when zeolite Y was applied to both fresh and sea waters although the dissolved organic matter occurring in natural water compartments can be retained as well but with a kinetics less favorable than that shown by sulfa drugs. The main host-guest & guest-guest interactions between zeolites and sulfa drugs were defined by IR and SS-NMR analysis, and augmented by computational studies. H-bonds and van der Waals type interactions between single molecules and zeolite Y or ZSM-5 were responsible for the irreversible extraction of sulfa drugs from water [1,3]. The occurrence of intramolecular medium strength H-bond in small sized sulfa drugs upon adsorption inside zeolite Y cage revealed the formation of dimeric species whose amidic or imidic tautomeric form were identified [1,3]. Rietveld refinement and IR analysis revealed that sulfa drugs incorporation into MOR caused a close vicinity of the heterocycle ring to the side pocket oxygens [2,3]. At 65°C, MOR gave rise to a sulfachloropyridazine reaction product with a 100% selectivity and SNAr mechanism [2]. Among the regeneration strategies approached, the thermal treatment and solvent extraction gave the best results. References [1] I. Braschi, G. Paul, G. Gatti, M. Cossi, L. Marchese. RSC Advances, 3, 7427 (2013). [2] A. Martucci, M.A. Cremonini, S. Blasioli, L. Gigli, G. Gatti, L. Marchese, I. Braschi. Micropor. Mesopor. Mat. 170, 274 (2013). [3] S. Blasioli, A. Martucci, G. Paul, L. Gigli, M. Cossi, C.T Johnston, L. Marchese. J. Coll. Interface. Sci., 419, 148 (2014).

The anionic nature of veterinary sulfonamide antibiotics (sulfa drugs) makes them highly mobile along soil profile and is responsible for their accumulation into water bodies. Owing to their environmental diffusion and persistence, sulfonamides are responsible to induce high level of resistance in bacteria through by-pass mechanism. To limit the diffusion of resistance determinants, it is of utmost importance to identify sustainable strategies against this antibiotic class to be adopted for water cleanup purpose. Recently, a high silica zeolite Y (SiO2/Al2O3 = 200) revealed an excellent ability to extract sulfonamides from pure water in terms of kinetics, capacity and irreversibility of the adsorption. In this study, the favorable adsorption kinetics and properties of the zeolite was confirmed in the presence of both acidic and neutral models of humic monomers (namely, caffeic acid and vanillin) in the 5-8 pH range. Sulfa drugs were quickly removed also when the sorbent was applied to fresh and sea waters. A displacement of adsorbed sulfa drugs from zeolite pores was observed for longer contact time and the mechanism was identified. Finally, among several regeneration techniques applied to exhausted zeolite samples, thermal treatment and solvent extraction showed the best performance.

DNA-based protocols are the golden standard for the diagnosis of infected plant material. Nevertheless, these methods are time-consuming and require trained personnel, with an efficacy depending on the sampling procedure. Given that plant responses induced by pathogens also include changes in emission of volatiles, the electronic-nose may represent a sensitive, accurate and operator-friendly alternative for rapid and reliable screening of asymptomatic plant material. In comparison with DNA-based diagnosis, which is hampered by the sampling procedure of the plant material, volatiles-based diagnosis can be performed on the whole plant. In the present study, the analysis of volatile compounds is used for the discrimination of two apple diseases: fire blight (Erwinia amylovora) and blossom blight (Pseudomonas syringae pv. syringae) on propagation material. The profile of volatiles emission was initially performed by gas chromatography-mass spectroscopy (GC-MS), proton-transfer time of flight mass spectroscopy (PTR-TOF-MS) to identify possible marker compounds. In addition, two different electronic noses, EOS507 (Sacmi Scrl, Imola, Italy) and PEN3 (Airsense Analytics GmbH, Schwering, Germany), both based on metal oxide semiconductors, were used for diagnosis. After the method validation on in vitro micropropagated plants, a sampling protocol was developed to scale up the diagnosis to real nursery conditions on cold-stored, asymptomatic dormant scions. Electronic-nose can be successfully used in practical conditions, such as nurseries or customs, to screen large quantity of asymptomatic plant material in order precisely steer molecular diagnosis

Il marciume bruno ed il marciume anulare, causati rispettivamente da Ralstonia solanacearum (Rs) e Clavibacter michiganensis subsp. sepedonicus (Cms) sono malattie delle patate largamente diffuse e di forte impatto economico. In questo studio, i composti volatili (VOCs) emessi da colture batteriche di Rs e Cms allevati su differenti substrati (TZ-, LPG-, and PDagar) sono stati analizzati mediante GC-MS, campionando lo spazio di testa con SPME. I risultati ottenuti sono stati confrontati con misure preliminari effettuate su patate sperimentalmente inoculate con Rs e Cms. La presenza dei patogeni favorisce la produzione di VOCs specifici per il tipo di substrato. In accordo con quanto osservato dall’analisi dello spazio di testa di Rs e Cms allevati su PDA, i tuberi infetti da Rs, confrontati con tuberi sani, producono significative variazioni dell’abbondanza relativa del picco GC-MS corrispondente all’acido 3-metilbutanoico. Per i tuberi infetti da Cms sono stati identificati 2 marcatori della malattia: il 2-propanolo, già osservato per Cms allevato su PDA, e il 3-metil-3-buten-2-one. Sembra ragionevole supporre che il metabolismo coinvolto nella crescita dei patogeni su PDAsia simile a quello coinvolto con il loro sviluppo in patata.

ELECTRONIC NOSE AS A RAPID AND INNOVATIVE TOOL FOR THE DIAGNOSIS OF GRAPEVINE CROWN GALL The electronic nose (E-nose) is an innovative device developed for microbiological, food/drink and environmental safety, and medical applications. E-nose comprises appropriate sensor arrays, able to detect and discriminate several flavours and odours from different sources. In the last decade, E-nose is being applied to recognize plant diseases caused from different quarantine bacterial pathogens such as Erwinia amylovora, Ralstonia solanacearum and Clavibacter michiganensis subsp. sepedonicus. In grapevines, tumourigenic strains of Agrobacterium vitis cause crown gall disease which may give serious problems in nurseries and vineyards. For the first time, a portable E-nose (PEN3) was used to discriminate between galled and healthy vines (controls), experimentally inoculated with two different strains of A. vitis and water, respectively. E-nose data were related to the increase of inoculation site diameters measured 9 months after inoculation with the pathogen. Preliminary gas chromatography-mass spectrometry (GC-MS) analysis were performed to identify volatile species from grapevine samples and to optimize experimental conditions for sensorial analysis. Solid phase microextraction (SPME) CAR/PDMS fibers were used to concentrate trace level vapour emissions. Spectra from tumoured vines and controls had almost identical volatile compositions, except the key compound styrene detected in infected samples. In plants, styrene formation is compatible with decarboxylation of cinnamic acid involved in secondary metabolism of plants. All data (E-nose sensors responses and diameter increases) from samples were processed with Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA). PCA application allowed a discrete separation of the samples into two groups, according to the presence or absence of disease symptoms. Moreover, the LDA model allowed the correct sample classification between healthy and galled vines (83.3%, cross validation). Tumours caused by the two strains of the pathogen were not discriminated according to the volatile compound composition identified by GC-MS. Although a larger number of grapevine samples should be analysed to create a more robust model, our results give interesting clues to go further with research on the diagnostic potential of this innovative system associated with multi-dimensional chemometric techniques. Keywords: E-nose; Agrobacterium vitis; GC-MS.

An actual and underestimated problem is the environmental pollution due to drug release by humans and feedstocks. Generally, after administration, drugs, (i.e. antibiotics, hormones, antiepileptics, pain-killers) are excreted from the organism, for the most part, unchanged. Drug residues are detected in the outlets of waste water treatment plants or in the agricultural wastes, as a consequence of manure spreading. Whether drugs are not adsorbed by soils, they move along the soil profile towards the groundwaters. Antibiotics, used in the treatment of diseases or as growth-promoting additives in animal feeds (banned from European Community on 2006 but still permitted in USA), are the most diffuse classes of veterinary drugs. Among these, sulfonamides are the fifth most widely used group of veterinary antibiotics within the EU and are considered ubiquitarious pollutants [1,2,3]. Because of their unique adsorption and ion-exchange properties, zeolites are versatile materials, commonly applied as adsorbent, molecular sieves or catalysts [4,5]. Sulfadiazine [4-amino-N-(4-methyl-2-pyrimidinyl)benzenesulfonamide], sulfamethazine [4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide], and sulfachloropyridazine [4-amino-N-(6-Cl-3-pyridazinyl)benzenesulfonamide] were purchased as certified standards. The organophylic faujasite (Y) zeolite with channel size comparable to sulfadrugs dimension was supplied by Tosoh Corporation (Japan) in H+-form (H-Y). With the aim to perform a cheap and environmentally friend clean-up system of waters contaminated by antibiotics, in this study we have investigated the adsorption of sulfonamides into H-Y zeolite. Sulfonamides were completely and quickly (t < 1 min) removed from water on H-Y zeolite. After 10 adsorption cycles, the maximal amounts of antibiotics adsorbed on zeolite ranged beetween 18-26% of zeolite dry weight as evidenced by thermogravimetric analyses. The adsorbed amount accounts for about one antibiotic molecule per zeolitic cage. Despite of the large amount of antibiotics adsorbed, the adsorption was not reversible in water. X-ray structure analyses were carried out by Rietveld method on zeolite before and after adsorption. Unit cell parameter variations and structural deformations after adsorption revealed the presence of sulfonamide molecules inside zeolitic cage. The most evident deformation effect was the lowering of Fd-3m real symmetry of the parent H-Y to Fd-3 after the adsorption of sulfadiazine or sulfachloropyridazine. As a consequence, remarkable deformations occur in the 12-membered ring channel system as reported in the table below. The deformation of H-Y after sulfamethazine adsorption caused a lowering of symmetry up to the monoclinic P2/m space group, as shown by the diffraction pattern here reported, preventing the Rietveld structure refinement. The arrows reported in the patter indicate the reflections forbidden in the cubic system.

I principali processi che condizionano il destino di uno xenobiotico nel comparto suolo-acqua sono l’adsorbimento al suolo e la degradazione nella soluzione circolante e sulle superfici solide del suolo. Mentre l’adsorbimento limita la mobilità dello xenobiotico lungo il profilo del suolo, la degradazione, biotica e abiotica, ne riduce la persistenza. Il cyhalofop-butile (CB), un inibitore dell’enzima acetil-CoA carbossilasi utilizzato in post-emergenza in risaia per il controllo del giavone (Echinocloa spp.) è un pro-erbicida presente nella formulazione commerciale Clincher. Una volta assorbito dalla pianta, il CB viene rapidamente idrolizzato a cyhalofop-acido (CA), la molecola biologicamente attiva. In questo lavoro sono stati studiati l’adsorbimento su due suoli (sedimento di risaia: pH 6,0, TOC 14 g kg-1, argilla:limo:sabbia 10:42:48% e suolo forestale: pH 7,1, TOC 73 g kg-1, argilla:limo:sabbia 20:54:26%) e la degradazione in condizioni sterili e non-sterili nel suolo e in acqua sia del CB che del CA. L’adsorbimento del CB risulta più elevato (KF 3,00; 1/n 0,80) ed irreversibile sul suolo forestale ricco in sostanza organica rispetto al sedimento di risaia (KF 0,52; 1/n 0,85) prevalentemente sabbioso dove invece è reversibile. Mentre nel sedimento di risaia la degradazione del CB porta esclusivamente a CA (t1/2 24 h), nel suolo forestale il CB si trasforma in CA (t1/2 32 h) che a sua volta è idrolizzato a CD e CAm (t1/2 15 h). In entrambi i suoli la degradazione è di tipo microbico, infatti, il CB ha una maggiore persistenza nei suoli sterili. In acqua non sterile, il CB degrada a CA, CAm e CD e la velocità di reazione cresce all’aumentare del pH: t1/2 4,8 d (pH 4); 1,0 d (pH 7); 0,8 d (pH 9). In soluzione sterile, la degradazione è più lenta e si osserva un unico metabolita (CA) e anche in questo caso la velocità è massima a pH alcalini: t1/2 347 d (pH 4); 85 d (pH 7); 2 d (pH 9).

I fenomeni di resistenza indotti da farmaci antibiotici costituiscono uno dei problemi emergenti degli ultimi anni. La porzione di antibiotici ad uso umano, veterinario e zootecnico che non viene abbattuta dai comuni impianti di depurazione entra nell’ambiente distribuendosi tra suolo ed acque secondo dinamiche dettate dalle caratteristiche chimico-fisiche e di persistenza tipiche della classe farmacologia di appartenenza. Gli antibiotici sulfamidici, noti per la loro persistenza nell’ambiente e quindi per la capacità di indurre resistenza, sono tra gli inquinanti più comunemente ritrovati nelle acque. In questo studio si è voluto mettere a punto un metodo di trattamento delle acque contaminate da antibiotici sulfamidici (sulfadiazina, sulfametazina e sulfacloropiridazina) tramite l’utilizzo di minerali zeolitici (tettosilicati) di facile reperimento, ecocompatibili e a basso costo. La zeolite che ha mostrato la capacità adsorbente migliore nei confronti di sulfamidici è una Faujasite di tipo Y in forma protonata (H-Y) con caratteristiche idrofobiche (alto rapporto Si:Al) e caratterizzata da una geometria tridimensionale dei canali, le cui dimensioni sono compatibili con quelle dei sulfamidici. Cinetiche di adsorbimento dei sulfamidici sulla zeolite hanno messo in evidenza che l’equilibrio di adsorbimento viene raggiunto in un tempo < 1 min. La quantità massima di farmaco adsorbibile dalla zeolite, misurata dopo adsorbimenti ciclici di soluzioni antibiotiche alla massima solubilità tramite tecniche cromatografiche e termogravimetriche, si attesta attorno al 25-40 mg antibiotico/100 mg zeolite. L’irreversibilità del processo è stata testata tramite prove di desorbimento in acqua. Analisi difrattometriche ai raggi X su polveri della zeolite prima e dopo l’adsorbimento dei sulfamidici mostrano variazioni dei parametri di cella dovute alla deformazione subita dalla struttura minerale in seguito all’ingresso degli antibiotici all’interno dei canali. Le analisi FT-IR mettono in evidenza una forte interazione tra le molecole di sulfamidico e la superficie interna della zeolite Y. La rimozione e il recupero degli antibiotici è immediato e completo quando condotto con acetonitrile. L’elevata velocità di adsorbimento dei sulfamidici sulla zeolite H-Y, l’elevata capacità di carico e l’irreversibilità in acqua del processo fanno di questo minerale un ottimo candidato all’abbattimento dei sulfamidici da acque con applicazioni interessanti in pescicoltura.

The study of cyhalofop-buthyl (CB) persistence on two different soils shows a t1/2 lower than 90 min. After few hours, CB hydrolized to cyhalofop acid (CA) which gives rise to degradation products different on the two soils. The t1/2 of CA is 42 d in the paddy-field soil and 3 h in the forest soil. The experiments repeated on sterile soils show the main role of microorganisms in the degradation. The adsorption of CA on sterile soils is low and characterized by a certain reversibility.

In the present work, the nature of the vanadium species formed on titanium catalysts at different vanadium loading was related to the catalyst behaviour for the deep oxidation of o-dichorobenzene. Chemical physical characterization results indicated that at vanadium loading up to 3% the titanium surface was covered with dispersed V5+ species in tetrahedral and octahedral coordination, while increasing the vanadium content the presence of highly dispersed V5+ species decreased, and additional formation of bulk V2O5 was observed. Catalytic tests indicated that the optimal loading of vanadium was 3%, suggesting that active phases are highly dispersed vanadium species on titania. Moreover, it was observed that incompletely oxidized products, such as dichloro maleic anhydride (2,5 furandione 3,4 dichloro) were formed in all catalysts and the concentration of these by-products increased with vanadium loading. Since the introduction of basic sites on the catalyst surface promoted DCMA formation, this effect was ascribed to the change of acid-basic properties of catalysts due to the increasing of vanadium in the system.