1,720,964 research outputs found
Performance of new and traditional fiber hemp (Cannabis sativa L.) cultivars for novel applications: stem, bark and core yield and chemical composition
No full textFinding a use for all components of hemp is key to improving the overall economics of fiber production from this crop. In this context, the core, a by-product of fiber production, has become increasingly important for new innovative applications. The aim of the present study was to compare traditional and new dioecious and monoecious fiber hemp cultivars in a 2-year field experiment in Central Italy, evaluating the variations on their fiber yield, bark and core production, and their chemical composition. The obtained results underlined the interesting potentiality of the new dioecious genotypes characterised by interesting fiber an non-fiber components which make appealing their utilization in several woven and non-woven applications. Thanks to the interesting chemical properties recorded for the core fraction, the full use of hemp biomass in a cascade approach can contribute to the total valorization of this versatile fiber crop for a modern biorefinery facility
Selezione, caratterizzazione ed impiego di ceppi batterici nella macerazione controllata della canapa
No full textLe colture ligno-cellulosiche per la produzione di biomassa da energia
No full textViene analizzato l’interesse crescente nell’uso delle biomasse a scopi energetici, come risposta alla vulnerabilità del sistema energetico italiano ed europeo. Le biomasse possono contribuire alla soluzione del problema attraverso la produzione di: i) energia termica su piccola scala; ii) calore per teleriscaldamento; iii) cogenerazione di energia elettrica e calore; iv) biogas, attraverso la digestione anaerobica; v) bioetanolo. Viene successivamente delineato l’ideotipo di pianta ottimale per la produzione di biomassa ligno-cellulosica, in grado di esprimere un’elevata efficienza dei fattori di produzione, in particolare acqua e azoto, ed una pari efficienza di trasformazione dell’energia sussidiaria. La trattazione prosegue con la descrizione botanica e con l’agrotecnica delle principali specie da biomassa per ambienti temperati, suddivise in erbacee ed arboree. Tra le prime, si considerano Sorgo da biomassa, Mais, Arundo, Miscanto, Panìco e Cardo; tra le seconde, Pioppo, Salice, Eucalipto e Robinia. Infine, viene descritta la Life Cycle Analysis come metodica per la valutazione dell’impatto ambientale delle filiere bio-energetiche che da queste piante si possono sviluppare, con esempi tratti dalla recente sperimentazione degli autori
Effects of selected pectinolytic bacterial strains on water-retting of hemp and fibre properties
No full textAims: To study the effect of selected bacterial strains on hemp water-retting and properties of retted fibre. Methods and Results: The trials were performed in laboratory tanks. The traditional water-retting process, without inoculum addition, was compared to a process modified by inoculating water tanks with two selected pectinolytic bacteria: the anaerobic strain Clostridium sp. L1/6 and the aerobic strain Bacillus sp. ROO40B. Six different incubation times were compared. Half the fibre obtained from each tank was combed. Micromorphological analyses were performed by scanning electron microscopy on uncombed and combed fibres. Moreover, organoleptic and chemical analyses of uncombed fibres were performed. Conclusions: The inoculum, besides speeding up the process, significantly improved the fibre quality. The fibre was not damaged by mechanical hackling, thanks to the good retting level obtained by the addition of selected strains, differently to what happened with the traditionally retted fibre. The best fibre quality was obtained after 3-4 days of retting with the addition of the bacterial inoculum. Significance and Impact of the Study: Retting is the major limitation to an efficient production of high-quality hemp fibres. The water-retting process and fibre quality were substantially improved by simultaneously inoculating water tanks with two selected pectinolytic strains
Exploitation of bacterial pectinolytic strains for improvement of hemp water retting
No full textRetting is the major limitation to an efficient production of textile hemp fibres. Traditional retting has been carried out by autochthonous bacterial community. Aerobic and anaerobic pectinolytic strains were isolated from hemp or flax sources and characterised. Anaerobic pectinolytic strains had a wide range of acid polygalacturonase (PG) activity, whereas aerobic isolates did not produce any acid PG activity, but only an alkalophylic one, suggesting they could play a minor role in the retting process, except in the early stages. Analysis of 16S rDNA sequences assigned anaerobic strains to the Clostridium genus and aerobic isolates to the Bacillus and Paenibacillus genus. C. felsineum and C. acetobutylicum were confirmed as the main anaerobic agents. Nevertheless, a high proportion of anaerobic and aerobic pectinolytic strains was assigned to C. saccharobutylicum and B. pumilus, respectively, both species never being described as involved in water retting. Anaerobic and aerobic strains with high PG activity were selected and characterized. PG activity is well correlated with the strain retting efficiency and improvement of the process was obtained by inoculating the retting water with spores of selected aerobic and anaerobic bacteria. An advisable feature of retting strains is the absence of cellulosolytic activity. An aerobic strain with no cellulosolytic activity was identified. In contrast, all the anaerobic isolates showed cellulosolytic activity. Mutagenesis was ineffective for selection of Cel-Pec+ mutants. Localization of the C. felsineum L1/6 PG activity was investigated
Coltivazione di Cardo con differenti apporti idrici per la produzione di biomassa da energia
No full text
- …
