Anna Ricci

Molecular Characterization of Jatropha curcas Resources and Identification of Population-Specific Markers

Jatropha curcas L. is cited as one of the best candidates for future oil and biodiesel production. It is widespread in many tropical and subtropical countries but has not yet received much genetic improvement. The objective of this study was to collect Jatropha germplasm and characterize it with molecular markers. A total of 64 genotypes, collected from seven geographic locations on two continents, were analyzed with 32 simple sequence repeat and two candidate gene-specific primers (ISPJ-1 gene and Curcin-P2 gene promoter). In general, markers were found to be highly conserved, and many (40%) were monomorphic in the studied populations. Polymorphic primers, which amplified population-specific fragments, were identified. The polymorphic information content of the polymorphic markers ranged from 0.03 to 0.47. Genetic similarity analysis identified two distinct groups at 0.73 DICE similarity coefficient. Group I included germplasm collected from the islands of Cuba and Cape Verde, and group II consisted of Brazil, Mozambique, and Senegal populations. Island genotypes were found to be very distinct compared to their mainland counterparts. Sequencing of monomorphic fragments identified single nucleotide polymorphism (SNP) between these two groups. High-resolution melting analysis of the SNP in the Jcps9 locus further confirmed the two gene pools. Sequencing of polymorphic fragments of the Jc03 locus identified a deletion in a (GT)4 repeat motif in the genotypes in group II. Several population-specific microsatellites and SNP markers have been recognized. The distinct Jatropha genotypes and the population-specific molecular markers identified in this study will be valuable resources in breeding programs.

Evaluation of benefits and risks associated with the agricultural use of organic wastes of pharmaceutical origin

Industrial fermentations for the production of pharmaceuticals generate large volumes of wastewater that can be biologically treated to recover plant nutrients through the application of pharmaceutical-derived wastes to the soil. Nevertheless, benefits and risks associated with their recovery are still unexplored. Thus, the aim of the present work was to characterize three potential organic residues (sludge, anaerobic digestate and compost) derived from the wastewater generated by the daptomycin production process. The main parameters evaluated were the physico-chemical properties, potential contaminants (heavy metals, pathogens and daptomycin residues), organic matter stabilization and the potential toxicity towards soil microorganisms and plants. The results showed that all the studied materials were characterized by high concentrations of plant macronutrients (N, P and K), making them suitable for agricultural reuse. Heavy metal contents and pathogens were under the limits established by European and Italian legislations, avoiding the risk of soil contamination. The compost showed the highest organic matter stabilization within the studied materials, whereas the sludge and the anaerobic digestate were characterized by large amounts of labile organic compounds. Although the pharmaceutical-derived fertilizers did not negatively affect the soil microorganisms, as demonstrated by the enzymatic activities, the sludge and the anaerobic digestate caused a moderate and strong phytotoxicity, respectively. The compost showed no toxic effect towards plant development and, moreover, it positively affected the germination and growth in lettuce and barley. The results obtained in the present study demonstrate that the valorization of pharmaceutical-derived materials through composting permits their agricultural reuse and also represents a suitable strategy to move towards a zero-waste production process for daptomycin.

Multi-approach characterization of organic sediment produced by an anaerobic digestion plant fed with pig slurry and stored for a long term in a lagoon

This study combined different approaches to characterize organic sediments produced by an anaerobic digestion plant feed with pig slurry, and accumulated for many years in a lagoon. The results of all analyses identified a certain homogeneity of the sediments. As a consequence of the pig diet, the sediment contained an high concentration of Zn (about 4gkg-1) and Cu (about 1.2gkg-1), which were mostly associated to the particles with a size ranging from 2 to 53μm. The sediment was made of large amount of organic matter, mostly cellulose and recalcitrant molecules, and 30-40% mineral fraction. XANES and XES spectroscopies indicated the presence of zinc phosphate (38%), zinc sulfide (32%), zinc carbonate (19%), and zinc oxide (11%). The presence in the sediment of forms characterized by a very scarce solubility, as also confirmed by the Zn and Cu chemical speciation, indicated a low bioavailability of these metals. However, although their low mobility, the high concentrations of Zn and Cu allowed to consider the sediment not suitable to use as a fertiliser due to the potential risk of metal interaction with the food chain.

Use of agricultural by-products in the development of an agro-energy chain: A case study from the Umbria region

Use of agricultural and livestock by-products for anaerobic digestion (AD), in total or partial substitution of the maize silage was evaluated from an environmental and economical point of view. The evaluation process included three methodological interdependent and consequential steps: the chemical stage at laboratory and plant level, the environmental and economic steps developing the Life Cycle Assessment and Life Cycle Costing jointly. The laboratory test showed that the two mixtures prepared with by-products, in partial (MIX A) and total (MIX B) substitution of maize silage, did not show differences in bio-methane production compared to a reference mixture with the 33% of maize silage. All mixtures tested at full-scale plant, showed the same performances, resulting in a similar energy production. Environmentally, MIX B increased greenhouse gas credits derived from the avoided production of mineral fertiliser for the energetic crops, resulting also in better economic performances. The break-even transport distances follow the positive environmental pattern result, in contrast to what was found for the break-even transport distances from the economic point of view.

Bioactive compounds and antioxidant characterization of three edible wild plants traditionally consumed in the Umbria Region (Central Italy): Bunias erucago L. (corn rocket), Lactuca perennis L. (mountain lettuce) and Papaver rhoeas L. (poppy)

The leaves of three edible wild plants, Bunias erucago L. (Corn rocket), Lactuca perennis L. (Mountain lettuce) and Papaver rhoaes L. (Poppy) were analysed for their proximate composition, some nutraceutical components and total antioxidant capacity. The protein levels ranged from 2.7 to 4.1 g/100 g of the edible portion. The range of dietary fibre content was 3.8 to 6.4 g/100 g of the edible portion. The amount of ash, carbohydrate and lipid ranged from 1.7 to 1.9, 3.3 to 4.4 and 0.22to 0.45 g/100 g of the edible portion, respectively. Lipids consisted mainly of polyunsaturated fatty acids with the highest value for the Bunias erucago L. (71.8 % of total fatty acids) and Lactuca perennis L. (70.0 %). Potassium (374.0-521.0 mg/100 g) and calcium (204.8-331.8 mg/100 g) were the most representative macro-elements in the species studied. The values of vitamin E, b-carotene and total vitamin C are included in the range from 0.91 to 2.61 mg/100 g, from 1,957 to 2,631 mg/100 g and from 19.2 to 31.0 mg/100 g, respectively. Our results showed that the total antioxidant capacity performed by the Oxygen Radical Absorbance Capacity (ORAC) method, which ranges from 27.2 to 63.7 μmol TE/g, is highly justifiable by the high content of phenolic compounds (159-246 mg GAE/100 g).