41 research outputs found
Innovative green catalysts to produce second generation sugars from non-food crops as a versatile biorefinery platform
No full textNowadays, the transformation of lignocellulosic biomass into added-value products such as reducing sugars is attracting great attention. Pentose and hexose sugars are very important industrial intermediates because they represent a versatile platform for the synthesis of several valuable compounds through chemical or biotechnological approaches. The present study was focused on the valorization of two promising non-food crops, such as giant reeds (Arundo donax L.) and cardoon (Cynara cardunculus L.) through the employment of homogeneous and heterogeneous catalysts for the production of C5 and C6 rich hydrolyzates. All reactions were performed in a microwave reactor and in aqueous medium
Electroanatomic mapping and ablation of atypical atrial flutter: comparison between successfully and unsuccessfully treated cases
No full textEthanol ablation of incessant postinfarction ventricular tachycardia: a usually neglected but effective alternative in refractory cases
No full textEfficacy and safety of electroanatomic mapping and ablation of left macroreentrant atrial tachycardia in patients with prior mitral valve surgery
No full textDevelopment and evaluation of a prototype for computer-based simulation of trans-septal catheterization
No full textCryoablation of typical atrial flutter using a 10-mm tip electrode is effecitve even with reduced application duration
No full textAN INTEGRATED AND VERSATILE BIOREFINERY MODEL TO PRODUCE LIPIDS FROM SECOND GENERATION BIOMASS
No full textIn order to replace fossil fuels and products with biofuels and bioproducts, and, at the same time, to avoid the competition food versus fuel related to renewable resources, innovative processes aimed to valorize lignocellulosic biomass and agro-food waste as raw material are highly attractive. Arundo donax L. or giant reed was defined as a promising lignocellulosic crop in the biorefinery field. The present study focused on investigating innovative, tailored and integrated strategies to firstly produce glucose and xylose from A. donax, by using green catalysts and microwaves as heating system, and then on fermenting them into fatty acid methyl esters (FAMEs) by oleaginous yeasts Lypomyces starkeyi and Cryptococcus curvatus. Moreover, glycerol deriving from FAMEs production was recycle as a fermentative substrate according to a zero waste biorefinery scheme. The quantitative conversion of hemicellulose into xylose was performed by optimizing both homogeneous and heterogeneous catalysis. The cellulose remained in the solid residue recovered at the end of the first step was then hydrolyzed by testing dilute H2SO4 or the enzymatic mixture Ctec2, obtaining an overall yield of about 40-50% g glucose/ g glucan for both approaches
Synergy between chemical and biological catalysis for new generation oil production according to the biorefinery perspective
No full textSingle cell oil (SCO) represents an innovative and versatile industrial platform to produce a wide range of added-value bioproducts such as biodiesel, bioplastics and biosurfactants. SCO is produced by oleaginous yeasts able to accumulate up to 70% of their dry cell weight as triacylglycerols (TAG). In order to make economically sustainable this process, second generation (2G) sugars, obtained from residual or dedicated lignocellulosic biomasses, must be used as fermentative substrate. Among lignocellulosic crops, Arundo donax L. was defined as a promising grass in the biorefinery field. The present study was focused on two main goals: the first one is the investigation of sustainable homogeneous and heterogeneous catalysts for the biomass hydrolysis in order to produce glucose and xylose, by using microwaves as heating system; the second one is the optimization of lignocellulosic hydrolysate fermentation into SCO by oleaginous yeast Lypomyces starkeyi and the transesterification of TGA into fatty acid methyl esters (FAMEs). The quantitative conversion of hemicellulose into xylose was performed by optimizing both homogeneous and heterogeneous catalysis. The cellulosic fraction remained in the solid residue recovered at the end of the first step was then hydrolyzed by testing dilute H2SO4 or the enzymatic mixture Ctec2, obtaining an overall yield for both approaches of about 40-50%, expressed as g glucose/g glucan in the starting biomass. The biological conversion of 2G sugars into oil reached the yield of 18 wt%, very close to the theoretical one (20 wt%)
Valorizzazione di biomassa da coltura dedicata (Arundo donax L.) e scarti cellulosici di cartiera con un processo combinato di catalisi e biocatalisi per l'ottenimento di bio-oli
No full textIl lavoro di tesi svolto è stato finalizzato all’ottenimento di bio-oli da biomasse tramite la sinergia tra catalisi chimica e biologica. Le biomasse utilizzate come materia prima sono state di due tipologie: una coltura energetica dedicata (Arundo donax L.) e scarti cellulosici derivati dall’industria cartaria. Per la produzione di zuccheri semplici fermentabili sono stati studiati quattro tipi di catalisi assistite da sistema di riscaldamento a microonde: autoidrolisi, catalisi con acidi di Brønsted (acido solforico e resina eterogenea Amberlyst-70) e acidi di Lewis (cloruro ferrico). Gli idrolizzati ottenuti ricchi in xilosio e glucosio sono stati utilizzati come substrato nel successivo step di bioconversione in olio di nuova generazione mediante l’ impiego del lievito oleaginoso Lipomyces starkeyi. Infine, i lipidi accumulati dentro le cellule sono stati estratti e quantificati per via gravimetrica
Sviluppo e valutazione di un simulatore di procedura di cateterismo transettale in elettrofisiologia
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