http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Tue, 21 May 2013 10:56:07 GMT 2013-05-21T10:56:07Z http://hdl.handle.net/2067/1388 Title: Lentinus (Panus) tigrinus augmentation of a historically contaminated soil: matrix decontamination and structure and function of the resident bacterial community Authors: Federici, Ermanno; Giubilei, Maria Angela; Cajthaml, Tomáš; Petruccioli, Maurizio; D'Annibale, Alessandro Abstract: The ability of Lentinus tigrinus to grow and to degrade persistent aromatic hydrocarbons in aged contaminated soil was assessed in this study. L. tigrinus extensively colonized the soil; its degradation activity after 60 d incubation at 28 ◦C, however, was mostly limited to dichloroaniline isomers, polychlorinated benzenes and diphenyl ether while the fungus was unable to deplete 9,10-anthracenedione and 7-H-benz[DE]anthracene-7-one which were the major soil contaminants. Although clean-up levels were limited, both density of cultivable heterotrophic bacteria and richness of the resident bacterial community in L. tigrinus microcosms (LtM) increased over time to a significantly larger extent than the respective amended incubation controls (1.9×109 CFU g−1 vs. 1.0×109 CFU g−1 and 37 vs. 16, respectively). Naphthalene- and catechol 2,3-dioxygenase gene copy numbers, however, decreased over time at a higher rate in LtMthan in incubation controls likely due to a higher stimulation on heterotrophs than xenobiotics-degrading community members. Description: L'articolo è disponibile sul sito dell'editore: http://www.sciencedirect.com Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2067/1388 2010-12-31T23:00:00Z 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 Fri, 31 Dec 2010 23:00:00 GMT http://hdl.handle.net/2067/1533 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. Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1412 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1408 Title: Effect of mobilizing agents on mycoremediation and impact on the indigenous microbiota Authors: Giubilei, Maria Angela; Leonardi, Vanessa; Federici, Ermanno; Covino, Stefano; Sasek, Vaclav; Novotny, Cenek; Federici, Federico; D'Annibale, Alessandro; Petruccioli, Maurizio Abstract: BACKGROUND: Mobilizing agents (MAs) have been suggested to improve the fungal degradation of polycyclic aromatic hydrocarbons (PAHs) in soil. Three different MAs (Tween 20, Tween 80 and soybean oil) were investigated for their ability to stimulate contaminant degradation by either Phlebia sp. DABAC 9 or Allescheriella sp. DABAC1 in a soil spiked with amixture of PAHs. RESULTS: Phlebia sp. and Allescheriella sp. markedly differed in their growth capabilities under non-sterile conditions and withoutMAs (3.0 versus 0.1 μg ergosterol g−1 soil, respectively). However, soybean oil led to a 35-fold increase of Allescheriella sp. growth. Contaminant degradations by Phlebia sp. DABAC 9 and Allescheriella sp. DABAC 1 were best supported by soybean oil and Tween 20, respectively. Enumeration of cultivable bacteria and denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA showed that microbial density and biodiversity were positively affected by the mycoremediation especially with Allescheriella sp., the use of which led to an evident detoxification. CONCLUSIONS: Allescheriella sp. DABAC 1 appears to be a promising strain in the remediation of PAH-contaminated soils. The different response of the two fungi to MAs addition confirms the stringent need for a preliminary lab-scale assessment of fungus/MA combinations prior to application. Description: L'articolo è disponibile sul sito dell'editore: http://www.onlinelibrary.wiley.com Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1408 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1409 Title: Stoned olive pomace fermentation with Pleurotus species and its evaluation as a possible animal feed Authors: Brozzoli, Viviane; Bartocci, Settimio; Terramoccia, Stefano; Contò, Giacomo; Federici, Federico; D'Annibale, Alessandro; Petruccioli, Maurizio Abstract: The use of stoned olive pomace (SOP) as an unconventional feedstuff for livestock is limited by its inherently low crude protein (CP) content and by the presence of anti-nutritional compounds such as phenols. Aim of this study was to assess whether solid-state fermentation of SOP with selective lignin-degrading fungi might ameliorate nutritional properties of the waste. Incubation of SOP, mixed (25%, w/w) with various conventional feedstuffs (i.e., wheat bran, wheat middlings, barley grains, crimson clover, wheat flour shorts and field beans), with Pleurotus ostreatus and Pleurotus pulmonarius led to significant CP increases, ranging from 7 to 29%, and marked removal (from ca. 50–90%) of phenols after 6 weeks. Both species, however, led to moderate delignification associated with significant consumption of hemicelluloses. Consequently, no improvements of both organic matter digestibility (OMD) and net energy of SOP–feedstuff mixtures occurred after the fungal colonization. Description: L'articolo è disponibile sul sito dell'editore: http://www.sciencedirect.com Thu, 31 Dec 2009 23:00:00 GMT http://hdl.handle.net/2067/1409 2009-12-31T23:00:00Z http://hdl.handle.net/2067/1410 Title: Short-term impact of dry olive mill residue addition to soil on the resident microbiota Authors: Sampedro, Inmaculada; Giubilei, Maria Angela; Cajthaml, Tomáš; Federici, Ermanno; Federici, Federico; Petruccioli, Maurizio; D'Annibale, Alessandro Abstract: The short-term response of the resident soil bacterial and fungal communities to the addition of 5% (w/w) of either dry olive mill residue (DOR), DOR treated with Phlebia sp. (PTDOR) or DOR previously extracted with water (WEDOR) was investigated. As opposed to bacteria, the diversity of fungi increased upon the amendments as assessed by denaturing gradient gel electrophoresis of 18S rDNA. Over the first 30 days, phospholipid fatty acids analyses indicated a gradual decrease in the relative abundances of Gram+ bacteria (from 44.8% to 37.9%) and a concomitant increase of Gram- bacteria (from 37.3% to 51.2%) in DOR-amended soil. A considerable increase in the fungal/bacterial ratio was observed after 7 days in DOR, WEDOR and PTDOR-amended soils with respect to the control (0.316, 0.165 and 0.265, respectively, vs. 0.011). The overall microbial activity was stimulated by the amendments as indicated by the higher activity levels of both dehydrogenase and fluorescein diacetate hydrolase. These results indicate that DOR at the application level examined is not toxic on soil microorganisms. Description: L'articolo é disponibile sul sito dell'editore: http://www.sciencedirect.com Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1410 2008-12-31T23:00:00Z http://hdl.handle.net/2067/1411 Title: Kinetic and redox properties of MnP II, a major manganese peroxidase isoenzyme from Panus tigrinus CBS 577.79. Authors: Petruccioli, Maurizio; Frascono, Marco; Quaratino, Daniele; Covino, Stefano; Favero, Gabriele; Mazzei, Franco; Federici, Federico; D'Annibale, Alessandro Abstract: A manganese peroxidase (MnP) isoenzyme from Panus tigrinus CBS 577.79 was produced in a benchtop stirred-tank reactor and purified to apparent homogeneity. The purification scheme involving ultrafiltration, affinity chromatography on concanavalin–A Sepharose, and gel filtration led to a purified MnP, termed ‘‘MnP II,’’ with a specific activity of 288 IU mg-1 protein and a final yield of 22%. The enzyme turned out to be a monomeric protein with molecular mass of 50.5 kDa, pI of 4.07, and an extent of N-glycosylation of about 5.3% of the high-mannose type. The temperature and pH optima for the formation of malonate manganic chelates were 45°C and 5.5, respectively. MnP II proved to be poorly thermostable at 50 and 60°C, with half-lives of 11 min and 105 s, respectively. Km values for H2O2 and Mn2+ were 16 and 124 lM, respectively. Although MnP II was able to oxidize veratryl alcohol and to catalyze the Mn2+ -independent oxidation of several phenols, it cannot be assigned to the versatile peroxidase family. As opposed to versatile peroxidase oxidation, veratryl alcohol oxidation required the simultaneous presence of H2O2 and Mn2+; in addition, low turnover numbers and Km values higher than 300 lM characterized the Mn2+ -independent oxidation of substituted phenols. Kinetic properties and the substrate specificity of the enzyme markedly differed from those reported for MnP isoenzymes produced by the reference strain P. tigrinus 8/18. To our knowledge, this study reports for the first time a thorough electrochemical characterization of a MnP from this fungus. Description: L'articolo è disponibile sul sito dell'editore: http://www.springerlink.com Wed, 31 Dec 2008 23:00:00 GMT http://hdl.handle.net/2067/1411 2008-12-31T23:00:00Z