Institute for Bioengineering and Biosciences

Funder

Organizational Unit

Publications

LipNanoCar Technology – A Versatile and Scalable Technology for the Production of Lipid Nanoparticles

Publication . Esgueira, Vera L.R.; Lopes, Clara P.A.; dos Santos, Ana Catarina A.; Pinto, Fátima; Sousa, Silvia A.; de Barros, Dragana P.C.; Leitão, Jorge H.; Fonseca, Luis P.

The extensive knowledge in the miniemulsion technique used in biocatalysis applications by the authors allowed the development of drug delivery systems that constitutes the LipNanoCar technology core for the production of lipid nanoemulsions and solid lipid nanoparticles. The LipNanoCar technology, together with adequate formulations of different oils, fatty acids, surfactants, and temperature, allows the entrapment of several bioactive and therapeutic compounds in lipid nanoparticles for cosmetic, nutrition, and pharmaceutical applications. The LIpNanoCar technology allowed lipid nanoparticles production with average sizes ranging from 100 to 300 nm and Zeta potentials between −55 and −20 mV. Concomitantly, high entrapment or encapsulation efficiencies (%EE) were achieved, as illustrated in this work for β-carotene and vitamins derivatives (>85%) for cosmetic application, and for antibiotics currently used in chemotherapy, like rifampicin (69–85%) and pyrazinamide (14–29%) against Mycobacterium tuberculosis (TB), and ciprofloxacin (>65%) and tobramycin (~100%) in Cystic Fibrosis (CF) respiratory infections therapy. Ciprofloxacin presented, for example, a quick-release from the lipid nanoparticles using a dialysis tubing (96% in the first 7 h), but slower than the free antibiotic (95% in the first 3 h). This result suggests that ciprofloxacin is loaded near the external surface of the lipid nanoparticles. The toxicity and validation of entrapment of antibiotics in lipid nanoparticles for Cystic Fibrosis therapy were assessed using Caenorhabditis elegans as an animal model of bacterial infection. Fluorescence microscopy of an entrapped fluorescent dye (DiOC) confirmed the uptake of the lipid nanoparticles by ingestion, and their efficacy was successfully tested in C. elegans. Burkholderia contaminans IST408 and Burkholderia enocepacia K56–2 infections were tested as model bacterial pathogens difficult to eradicate in Cystic Fibrosis respiratory diseases.

2022-05-19Book part

Restricted access

Production and characterization of protein-rich extracts from the red macroalga Gelidium corneum and its industrial agar extraction residues

Publication . Mateus, Marília; Mão de Ferro, Rita; Pinheiro, Helena M.; Machado, Remígio; R. da Fonseca, M. Manuela; Sapatinha, Maria; Pires, Carla; Marmelo, Isa; Marques, António; Nunes, Maria Leonor; Motta, Carla; Cesário, M. Teresa

The red macroalga Gelidium corneum is a species commercially exploited for agar extraction, though with enormous potential for other industrial applications. This work aimed to produce protein-rich extracts from the crude alga and from residues of the industrial agar extraction process by applying different extraction and recovery procedures, and to characterize the obtained protein extracts. The sequential implementation of two water extractions followed by two alkaline extractions resulted in the recovery of 12.0 ± 1.2 % and 15.4 ± 0.9 % of the total protein contents of the crude alga and industrial residues, respectively. Two sequential water extractions assisted by Celluclast® and Alcalase® enzymes followed by two alkaline extractions recovered 52.1 ± 1.7 % and 36.5 ± 1.3 % of the protein contents of the crude alga and industrial residues, respectively. Extracts produced by these processes were characterized focusing on proximal composition, protein accessibility, nutrition and antioxidant potential, showing value as aquaculture feed ingredients. As all protein products revealed high carbohydrate contents and, aiming at enriching protein content, different protein precipitation methods were assessed, namely through ammonium sulfate precipitation and pH-shift protocols. The pH-shift method in sequential mode proved to be simple and fast with low reagent consumption. The purification of extracts by this precipitation mode allowed precipitating up to 72 % of the extracted protein. The results obtained suggest that protein concentrates extracted from Gelidium corneum appear to be promising sustainable sources for fish feed production, owing to their essential amino acid content, protein bioaccessibility and antioxidant properties.

2024-02-09Journal article

Open access