29 documents found, page 1 of 3
Poly(butylene succinate)-based composites with technical and extracted lignins ...
Melro, Elodie; Duarte, Hugo; Eivazi, Alireza; Costa, Carolina; Faleiro, Maria Leonor; Rosa Da Costa, Ana; Antunes, Filipe E.; Valente, Artur J. M.Poly(butylene succinate) (PBS) has been drawing attention as a reliable biodegradable and sustainable alternative to synthetic petroleum-based polymers. In this study, PBS-lignin composites were developed using a recently extracted lignin (LA-lignin) from pine wood residues employing an innovative sustainable approach. These composites were systematically compared with PBS-based composites formed with commonly ...
Nanofibrillated cationic cellulose derivatives as flocculants for domestic wast...
Ribau Teixeira, Margarida; Ismail, Abdullah; Medronho, Bruno; Alves, Luís; Pedrosa, Jorge F.S.; Ferreira, Paulo J.T.; Serrão Sousa, VâniaNatural-based coagulants have emerged as a reliable option to implement more sustainable operations and management of wastewater treatment plants. This work aims at evaluating the use of cationic nanofibrillated celluloses (cNFC) as novel bio-based flocculants to treat domestic wastewaters by the most widely employed treatment process – coagulation/flocculation. Two cNFC samples were prepared with different cha...
Pontastacus leptodactylus (Eschscholtz, 1823) and Faxonius limosus (Rafinesque,...
Nuc, Zofia; Brusotti, Gloria; Catenacci, Laura; Grenha, Ana; Pontes, Jorge Filipe; Pinto-da-Silva, Joana; Rosa Da Costa, Ana; Moro, PaolaThe growing demand for chitin and chitosan makes it necessary to look for new sources of these polymers and to develop more environmentally friendly methods for their isolation. The subjects of the current study were chitin and chitosan extracted from shells of two crayfish species: <i>P. leptodactylus</i> and <i>F. limosus</i>. The obtained polymers were characterized by physicochemical properties (molecular w...
Respirable konjac glucomannan microparticles as antitubercular drug carriers: E...
Guerreiro, Filipa; Pontes, Jorge Filipe; Gaspar, Maria Manuela; Rosa Da Costa, Ana; Faleiro, Maria Leonor; Grenha, AnaPulmonary delivery of drugs is potentially beneficial in the context of lung disease, maximising drug concentrations in the site of action. A recent work proposed spray-dried konjac glucomannan (KGM) microparticles as antitubercular drug (isoniazid and rifabutin) carriers to treat pulmonary tuberculosis. The present work explores in vitro and in vivo effects of these microparticles, focusing on the ability for ...
Levulinic acid-based “green” solvents for lignocellulose fractionation: on the ...
Melro, Elodie; Riddell, Alexander; Bernin, Diana; Rosa Da Costa, Ana; Valente, Artur J. M.; Antunes, Filipe E.; Romano, Anabela; Norgren, MagnusThe high potential use of lignin in novel biomaterialsand chemicalsrepresents an important opportunity for the valorization of the mostabundant natural resource of aromatic molecules. From an environmentalperspective, it is highly desirable replacing the hazardous methodscurrently used to extract lignin from lignocellulosic biomass anddevelop more sustainable and environmentally friendly approaches.Therefore, i...
Comparative study of the production of cellulose nanofibers from agro-industria...
Ribeiro Lima, Alexandre; Cristofoli, Nathana L.; Rosa Da Costa, Ana; Saraiva, Jorge A.; Vieira, MargaridaThe study of the suitability of two isolation processes to produce cellulose nanofibers (CNFs) from Salicornia ramosissima waste, with potential applicability as a reinforcing agent of polymeric composites was carried out. To separate the cellulose fibrils from the cell wall and obtain CNFs an alkaline treatment was applied followed by a bleaching treat-ment and, the insoluble residue was next hydrolyzed by eit...
Structural characterization of exopolysaccharides obtained from Porphyridium cr...
Cristofoli, Nathana L.; Ribeiro Lima, Alexandre; Rosa Da Costa, Ana; Evtyugin, Dmitry; Silva, Carlos; Varela, João; Vieira, MargaridaMicroalgae produce and secrete large quantities of polysaccharides into the culture medium that is discarded when biomass is separated. The main objective of this study was to add value to the exhausted culture medium (ECM) of Porphyridium cruentum through the recovery of extracellular polysaccharides (EPS) by different extracting and purifying methods for the future biotechnological applications. The ECM was s...
Tunning processes for organic matter removal from slaughterhouse wastewater tre...
Simão Madeira, Luís Miguel; Almeida, Adelaide; Rosa Da Costa, Ana; Mestre, Ana S.; Carvalho, Fátima; Ribau Teixeira, MargaridaAdsorption using unmodified/modified commercial activated carbons and constructed wetlands (CW) planted with Vetiveria zizanioides were evaluated as tuning processes for lowering chemical oxygen demand (COD) from slaughterhouse wastewater pretreated by the integrated process of immediate one-step lime precipitation and atmospheric carbonation. Powdered and granular activated carbons (PAC and GAC), and PAC and G...
Probing cellulose–solvent interactions with self-diffusion NMR: Onium hydroxide...
Medronho, Bruno; Pereira, Ana; Duarte, Hugo; Gentile, L.; Rosa Da Costa, Ana; Romano, A; Olsson, U.The molecular self-diffusion coefficients were accessed, for the first time, in solutions of microcrystalline cel-lulose, dissolved in 30 wt% and 55 wt% aqueous tetrabutylammonium hydroxide, TBAH (aq), and in mixtures of 40 wt% TBAH (aq) with an organic co-solvent, dimethylsulfoxide (DMSO), through pulsed field gradient stim-ulated echo NMR measurements. A two-state model was applied to estimate alpha (i.e., av...
β-Cyclodextrin inclusion complexes of combined Moroccan Rosmarinus officinalis,...
El Kharraf, Sara; Farah, Abdellah; EL-GUENDOUZ, Soukaina; Lourenço, João P.; Rosa Da Costa, Ana; El Hadrami, El Mestafa; Machado, Alexandra M.A combined volatile oil (VO) was extracted from Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium by simultaneous hydro- and steam-distillation, and encapsulated in beta-cyclodextrin by co-precipitation. Response surface methodology (RSM) was used to optimize microencapsulation conditions. The variable recovered powder, VO retention degree, and inclusion efficiency were investigated based on t...