Determination of sdLDL particles in patients with Familial Hyercholesterolaemia and Familial Combined Hyperlipidaemia

Several studies demonstrated that sdLDL are an emerging cardiovascular (CV) risk factor. The objective of this study was sdLDL measurement in patients with genetic diagnosis of Familial Hypercholesterolaemia (FH) and clinical diagnosis of Familial Combined Hyperlipidaemia (FCHL) to establish a relation between sdLDL, CV risk and the efficacy of therapeutics. Lipid profile was determined using a polyacrylamide gel electrophoresis system that separates the particles in serum that contain cholesterol. The lipidogram obtained classifies the patients as being profile A (low CV risk) or B (high CV risk) depending on the sdLDL concentration. The lipid profile was obtained from 43 FH adults and 46 FCHL adults, index and relatives. FH and FCHL patients without medication and with high sdLDL (>6mg/dl) have significant higher levels of total cholesterol, LDL and ApoB and FCHL patients also have significant higher triglycerides, compared to FH and FCHL patients with sdLDL levels under recommended values. Under medication FH patients have significant higher ApoB levels and lower HDL, and FCHL patients have significant higher total cholesterol, LDL and ApoB levels. Interestingly, 71,4% of FCHL patients under medication presented high CV risk profile, showing that statins seem not to decrease sdLDL levels and neither CV risk. Also FCHL patients are not well medicated or do not respond to usual medication to decrease cholesterol. These preliminary results indicate that sdLDL could be a good biomarker for treatment control but further studies are needed to evaluate the effect of medication in sdLDL levels in FH and FCHL patients.Alexandra Gomes was funded by FCT PIC/IC/83020/2007, Tânia Santos was funded by FCT PIC/IC/83333/2007 and project grant FCT PIC/IC/83333/200

Encapsulation of omega-3 fatty acids in bio-based nanoemulsions: physical and chemical characterization

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] The use of nanotechnology can offer several advantages, not only improving water solubility but also in the increase of bioavailability of lipophilic bioactive compounds. Omega-3 polyunsaturated fatty acids (ω-3 fatty acids) are known for their functional properties such as: improving cardiovascular health, decrease inflammation, increase cognitive function, and positively influence neurological and visual development. However, ω-3 fatty acids are highly susceptible to oxidation, have an intense odour and present low water solubility, which makes their direct application in foods extremely difficult. Nanoencapsulation (through nanoemulsions) may be used to reduce these problems. In this work, lactoferrin (Lf), a protein derived from milk with a wide range of reported biological activities (e.g. antioxidant, antimicrobial and cancer prevention), was used as natural emulsifier for the development of oil-in-water nanoemulsions. Nanoemulsions were produced with a high-pressure homogenizer applied for 5 cycles at 20000 psi. Different Lf concentrations (0.2; 0.6; 1; 2; 3; 4 and 5% (w/w)) were tested. The nanoemulsions’ physical properties were evaluated in terms of size and ζpotential using dynamic light scattering (DLS) and by surface tension using the Ring method. The morphology of nanoemulsions was analysed by transmission electron microscopy (TEM). The physical and chemical stability of these nanoemulsions was assessed during 50 days, at storage temperatures of 4 ºC and 25 ºC, being the chemical stability of nanoemulsions evaluated by antioxidant activity measurements using the DPPH radical scavenging assay. [...]info:eu-repo/semantics/publishedVersio

Encapsulation and controlled release of bioactive compounds in lactoferrin-glycomacropeptide nanohydrogels : curcumin and caffeine as model compounds

Curcumin and caffeine (used as lipophilic and hydrophilic model compounds, respectively) were successfully encapsulated in lactoferrin-glycomacropeptide (Lf-GMP) nanohydrogels by thermal gelation showing high encapsulation efficiencies (>90 %). FTIR spectroscopy confirmed the encapsulation of bioactive compounds in Lf-GMP nanohydrogels and revealed that according to the encapsulated compound different interactions occur with the nanohydrogel matrix. The successful encapsulation of bioactive compounds in Lf-GMP nanohydrogels was also confirmed by fluorescence measurements and confocal laser scanning microscopy. TEM images showed that loaded nanohydrogels maintain their spherical shape with sizes of 112 and 126 nm for curcumin and caffeine encapsulated in Lf-GMP nanohydrogels, respectively; in both cases a polydispersity of 0.2 was obtained. The release mechanisms of bioactive compounds through Lf-GMP nanohydrogels were evaluated at pH 2 and pH 7, by fitting the Linear Superimposition Model to the experimental data. The bioactive compounds release was found to be pH-dependent: at pH 2, relaxation is the governing phenomenon for curcumin and caffeine compounds and at pH 7 Ficks diffusion is the main mechanism of caffeine release while curcumin was not released through Lf-GMP nanohydrogels

Influence of chitosan coating on protein-based nanohydrogels properties and in vitro gastric digestibility

Chitosan coating was applied in Lactoferrin (Lf)-Glycomacropeptide (GMP) nanohydrogels by layer-by-layer coating process. A volume ratio of 0.1 of Lf-GMP nanohydrogels (0.2 mg.mL-1, at pH 5.0) to chitosan (1 mg.mL-1, at pH 3) demonstrated to be the optimal condition to obtain stable nanohydrogels with size of 230 ± 12 nm, a PdI of 0.22 ± 0.02 and a -potential of 30.0 ± 0.15 mV. Transmission electron microscopy (TEM) images showed that the application of chitosan coating in Lf-GMP did not affect the spherical shape of nanohydrogels and confirmed the low aggregation of nanohydrogels in solution. The analysis of chemical interactions between chitosan and Lf-GMP nanohydrogels were performed by Fourier transform infrared spectroscopy (FTIR) and by circular dichroism (CD) that revealed that a specific chemical interaction occurring between functional groups of protein-based nanohydrogels and active groups of the chitosan was established. The effect of chitosan coating on release mechanisms of Lf-GMP nanohydrogels at acid conditions (pH 2, 37 ºC) was evaluated by the encapsulation of a model compound (caffeine) in these systems. Linear Superposition Model was used to fit the experimental data and revealed that Fick and relaxation mechanisms are involved in caffeine release. It was also observed that the Fick contribution increase with the application of chitosan coating. In vitro gastric digestion was performed with Lf-GMP nanohydrogels and Lf-GMP nanohydrogels with chitosan coating and it was observed that the presence of chitosan improve the stability of Lf and GMP (proteins were hydrolysed at a slower rate and were present in solution by longer time). Native electrophoreses revealed that the nanohydrogels without coating remained intact in solution until 15 min and with chitosan coating remained intact until 60 min, during gastric digestion.Ana I. Bourbon, Ana C. Pinheiro and Miguel A. Cerqueira acknowledge the Fundação para a Ciência e Tecnologia (FCT, Portugal) for their fellowships SFRH/BD/73178/2010, SFRH/BPD/101181/2014 and SFRH/BPD/72753/2010, respectively). The authors would like to acknowledge Jorge Padrão from CEB, University of Minho for helping in antimicrobial measurements and to Rui Fernandes from IBMC, University of Porto for assistance in taking the TEM pictures. Also, the authors would like to thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project “BioInd – Biotechnology and Bioengineering for improved Industrial and Agro-Food processes”, REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER

Transport mechanism of macromolecules on hydrophilic bio-polymeric matrices : diffusion of protein-based compounds from chitosan films

The transport mechanism of protein-based bioactive compounds (a peptide fraction from whey protein concentrate, glycomacropeptide and lactoferrin), from chitosan films to liquid medium, was studied. Mathematical models were used to discuss the transport mechanism. Data from release experiments was successfully described by a model which accounts for both Fick and Case II transport – the linear superimposition model. Results show that the mechanism of transport and the effect of temperature and peptide type could be related with physical properties of chitosan films where the tested bioactive compounds were incorporated. The approach presented here allows interpretation of the phenomena involved in mass transport in the systems studied and, once extended to other systems, may contribute to an understanding of transport in hydrophilic bio-polymeric matrices.This work was supported by Fundacao para a Ciencia e a Tecnologia through project PTDC/AGR/ALI/67194/2006. Authors Ana C. Pinheiro, Ana I. Bourbon and Mafalda A.C. Quintas gratefully acknowledge their Grants SFRH/BD/48120/2008, SFRH/BD/73178/2010 and SFRH/BPD/41715/2007, respectively

Bio-based coatings for food processing applications

Innovations constantly appear in food packaging, always aiming at creating a more efficient quality preservation system while improving foods attractiveness and marketability. The utilization of renewable sources for packaging materials, such as hydrocolloids from biological origin, is one of the main trends of the food packaging industry. Edible coatings have been considered as one of the potential technologies that can be used to increase the storability of foods and to improve the existent packaging technology, helping to ensure microbial safety and preservation of food from the influence of external factors. In view of these advantages concerning the application of edible coating solutions, recent developments have been achieved regarding the utilization of new materials. Work has been developed on the application of galactomannans, chitosan, Policaju, and collagen-based coatings on fruits (1, 2), cheese (3, 4) and fish (5), with the incorporation in some cases of antimicrobials and antifungals (5,7). Recently, the layerby- layer technique was used to apply these bio-based coatings as a nanolayer in fruits such as pears and mangoes (8, 9) using materials such as chitosan, lysozyme, pectin and k-carrageenan. Globally, results showed that the application of bio-based coatings on food products lead to the improvement of the quality and to the increase of shelf-life of food products. It is viewed that in a near future tailored edible packaging solutions based on natural biopolymers can be applied to selected foods, partially replacing nonbiodegradable/ non-edible plastics.info:eu-repo/semantics/publishedVersio

Partículas de gel biopoliméricas para aplicações alimentares e farmacêuticas

National Patent (INPI)info:eu-repo/semantics/publishedVersio