15 documents found, page 1 of 2

Unravelling the distinct crystallinity and thermal properties of suberin compou...

The main purpose of this study was to investigate the potential of suberin (a naturally occurring aromatic-aliphatic polyester ubiquitous to the vegetable realm) as a renewable source of chemicals and, in particular, to assess their physical properties. A comparison between cork and birch suberin fragments obtained by conventional depolymerisation processes (hydrolysis or methanolysis) is provided, focusing ess...

Spent coffee grounds as a renewable source for ecopolyols production

BACKGROUNDBased on the biorefinery concept, the main focus of this work was the increase in value of spent coffee grounds via an acid liquefaction process using polyhydric solvents in the presence of sulfuric acid, at moderate temperature. For that purpose the effect of temperature, sulfuric acid concentration and time on biomass conversion was studied using design of experiments combined with statistical analy...

Bacterial cellulose membranes as transdermal delivery systems for diclofenac: I...

Bacterial cellulose (BC) membranes were explored as novel nanostructured transdermal delivery systems for diclofenac sodium salt (a typical non-steroidal anti-inflammatory drug). Diclofenac sodium salt loaded BC membranes were prepared through a simple methodology, using glycerol as plasticizer, and characterized in terms of structure, morphology and swelling behavior. The membranes were very homogeneous, quite...

Nanostructured Bacterial Cellulose-Poly(4-styrene sulfonic acid) Composite Memb...

The present study reports the development of a new generation of bio-based nanocomposite proton exchange membranes based on bacterial cellulose (BC) and poly(4-styrene sulfonic acid) (PSSA), produced by in situ free radical polymerization of sodium 4-styrenesulfonate using poly(ethylene glycol) diacrylate (PEGDA) as cross-linker, followed by conversion of the ensuing polymer into the acidic form. The BC nanofib...

Ecopolyol Production from Industrial Cork Powder via Acid Liquefaction Using Po...

Ecopolyol production from acid liquefaction of cork powder was studied for the first time using PEG 400 and glycerol as liquefaction solvents in the presence of sulfuric acid at moderate temperature and atmospheric pressure. The effect of the temperature, concentration of catalyst, and time on the liquefaction yield has been investigated using a fixed set of reaction conditions namely, a liquefaction solvent mi...

Antifungal activity of transparent nanocomposite thin films of pullulan and sil...

Silver has been mainly investigated as an antibacterial agent and less as a fungicide in which concerns antimicrobial properties. In this research, the antifungal activity of composite films of pullulan and Ag nanoparticles (NP) against Aspergillus niger was evaluated using standard protocols. These new materials were prepared as transparent cast films (66-74 mu m thickness) from Ag hydrosols containing the pol...

Eucalyptus globulus Bark as Source of Tannin Extracts for Application in Leathe...

This paper reports the extraction of Eucalyptus globulus bark and a concentration strategy to obtain a phenolic-rich extract for application in the leather tanning industry. The profiles of total phenolic compounds (TPC) and tannins contents in water and dilute alkali as a function of extraction temperature and time led to the selection of the best conditions concerning extraction yield and selectivity. The sel...

The role of nanocellulose fibers, starch and chitosan on multipolysaccharide ba...

Thin nanocomposite films of thermoplastic starch, chitosan and cellulose nanofibers (bacterial cellulose or nanofibrillated cellulose) were prepared for the first time by solvent casting of water based suspensions of the three polysaccharides. The role of the different bioploymers on the final properties (thermal stability, transparency, mechanical performance and antimicrobial activity) of the films was relate...

New nanomaterials from bacterial cellulose: A perspective on the research at th...

Valorization of olive mill residues: Antioxidant and breast cancer antiprolifer...

Phenolic composition, antioxidant and breast cancer antiproliferative activities of water and methanol/water derived extracts from olive pomace (OP) and dry olive mill residue (DOR), from Portuguese industries, were studied. DOR water (DORW) extracts showed the highest extraction yield; as well as the highest total phenolic content (TPC) and hydroxytyrosol (HT) (similar to 25 mg/g extract). HPLC-ESI-MS analysis...