http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2013-05-21T23:54:22Z http://hdl.handle.net/2067/1533 Title: Organic matter transformation and detoxification in dry olive mill residue by the saprophytic fungus Paecilomyces farinosus Authors: Sampedro, Inmaculada; Cajthaml, Tomáš; Marinari, Sara; Petruccioli, Maurizio; Grego, Stefano; D'Annibale, Alessandro Abstract: Dry olive mill residue (DOR), the by-product of the two-phase extraction process, is very rich in organic matter and nutritionally relevant cations. For this reason, the agronomic use of this waste has been suggested although DOR exhibits significant phytotoxicity. The objective of this study was to investigate the impact of Paecilomyces farinosus on both organic matter modification and detoxification of this waste.Humification ratio in DOR colonized by the fungus for 20 weeks was increased by about 65% with respect to the abiotic control and humification index reached 0.38, a value that characterizes well-humified materials. High performance size-exclusion chromatography of humic acids from fungal cultures showed a marked increase in both weight-averaged and number-averaged molecular weights with respect to abiotic controls. Water-soluble phenols were reduced by 45% in 20-week-old P. farinosus cultures on DOR and mass-balance ultra-filtration showed that the relative abundance of the molecular weight fraction of phenols above 30 kDa increased from 31 to 72% suggesting the occurrence of polymerization.Experiments performed with alfalfa grown on soils containing 2.5% (w/w) of abiotic controls and fungaltreated DOR showed that phytotoxicity was totally suppressed in the waste that underwent fungal treatment. Description: L'articolo è disponibile sul sito dell'editore: http://www.sciencedirect.com 2010-12-31T23:00:00Z http://hdl.handle.net/2067/1412 Title: Immobilized inocula of white-rot fungi accelerate both detoxification and organic matter transformation in two-phase dry olive-mill residue Authors: Sampedro, Inmaculada; Cajthaml, Tomáš; Marinari, Sara; Stazi, Silvia Rita; Grego, Stefano; Petruccioli, Maurizio; Federici, Federico; D'Annibale, Alessandro Abstract: The potential use for agronomic purposes of dry olive-mill residue (DOR), solid waste from the olive oil two-phase extraction process, might be impaired by its phytotoxicity. Although fungal treatments can detoxify DOR, long times are required for these processes. The objective of this study was to assess whether the addition of immobilized fungal inocula to DOR might improve colonization rates, thus reducing the time necessary for its detoxification and bioconversion. Inocula of Panus tigrinus CBS 577.79 and Phlebia sp. DABAC 9 immobilized on either chopped maize stalks or polyurethane sponge (PS) led to higher removals of both phenols and phytotoxicity from DOR than free inocula after 4 weeks of incubation. Best dephenolization (85%) was with PS-immobilized Phlebia sp., the use of which reduced germinability inhibition of Lepidium sativum and Lactuca sativa by 80 and 71.4%, respectively. Regardless of the type of inoculant, a low degree of humification was obtained. 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1775 Title: Soil organic matter in the sustainable agriculture: Source or sink of carbon? Authors: Grego, Stefano; Lagomarsino, Alessandra Abstract: Stocks of Soil Organic Matter (SOM) are controlled by the balance between carbon inputs derived from plant production and outputs through decomposition processes mediated by heterotrophs. The importance and function of SOM is largely due to its dynamic nature, being continuously synthesised, mineralised and rearranged. Besides CO2 production, SOM decomposition provides metabolic energy for microorganisms and mineral nutrients available for plant uptake. Intensive agriculture stimulates the rate of decomposition, because the physical disturbance exposes oxygen diffusion and enhancing C mineralisation. Moreover, a large amount of crop products are removed, thus subtracting C to the ecosystems. Raising the soil C content means increasing the C input, decreasing the output or a combination of the two through improved land management. In particular, in agricultural soils, increasing C inputs is the major pathway for increasing soil C storage, without depleting nutrients released through SOM mineralization. This could be achieved by the use of animal manure, crop residues, sewage sludge and compost, improving rotations with higher C inputs to the soil and reducing soil disturbance with zero tillage practices. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/1776 Title: Soil organic carbon balance using Century model Authors: Di Tizio, Alessandra; Grego, Stefano Abstract: Mathematical modelling has widely been used during the last 20 years to estimate and predict soil organic carbon (SOC) balance and nutrients dynamic on the landscape scale. The model simulations are applied and developed to assess the long-term effects of climate and management practices on SOC in the different land use. However, there are characteristics of the models, such as simplifications, complex nonlinear interactions etc., which limit their use and imply wide evolution to improve the models performance. The present work illustrates the differences among the main SOC models developed for forest, agricultural and grassland land-use, and their limits and prospects. Particularly the CENTURY model and an application of this model in a Mediterranean agroecosystems, characterized by organic and conventional managements, are described. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/1777 Title: Tetacycline Determination from honey using HPLC Method Authors: Moise, Adela; Marghitas, Liviu; Corradini, Danilo; Grego, Stefano Abstract: The antibiotics are chemical substances, used in treatment of some disease in animals. Their use in inadequate quantities creates the residues accumulation in food. The tetracycline, which is a broad spectrum antibiotic used for the treatment of some disease at honeybees, was put in evidence and quantify by HPLC method. We used a HPLC with Gold System computer’s software, Beckman pumps and injector, and determination at 355 nm. After establishment of analyze parameters, 10 honey samples from different areas of Romania were analyzed. A number of 3 samples were determined as positive, containing different quantities of antibiotic. 2003-12-31T23:00:00Z http://hdl.handle.net/2067/1657 Title: Copper distribution among physical and chemical fractions in a former vineyard soil Authors: Lagomarsino, Alessandra; Marabottini, Rosita; Grego, Stefano; Stazi, Silvia Rita Description: L'articolo è disponibile sul sito dell'editore: www.edizioniplus.it 2009-12-31T23:00:00Z http://hdl.handle.net/2067/1942 Title: The effect of organic and conventional cropping systems on CO2 emission from agricultural soils: preliminary results Authors: Mancinelli, Roberto; Campiglia, Enio; Di Tizio, Alessandra; Lagomarsino, Alessandra; Grego, Stefano Abstract: The effects of different agricultural systems on soil organic carbon content and CO2 emission are investigated in this work. In a long-term experiment a conventional system, characterized by traditional agricultural practices (as deep tillage and chemical input) was compared with an organic one, including minimum tillage, green manure and organic fertilizers. Both systems have a three-year crop rotation including pea – durum wheat – tomato; the organic system is implemented with the introduction of common vetch (Vicia sativa L.) and sorghum (Sorghum vulgare bicolor) as cover crops. In the year 2006 (5 years after the experimentation beginning) was determined the soil C content and was measured the CO2 emissions from soil. The first results showed a trend of CO2 production higher in organic soils in comparison with conventional one. Among the two compared cropping systems the higher differences of CO2 emission were observed in tomato soil respect to the durum wheat and pea soils, probably due to the vetch green manuring before the tomato transplanting. These results are in agreement with the total organic carbon content and water soluble carbon (WSC), which showed the highest values in organic soil. The first observations suggest a higher biological activity and CO2 emission in organic soil than conventional one, likely due to a higher total carbon soil content. 2006-12-31T23:00:00Z