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The intestinal mucus layer prevents cellulose nanocrystals from reaching the epithelium and can modulate lipid and bile absorption., It is well recognised that the average UK diet does not contain sufficient fibre. However, the introduction of fibre is often at the detriment of the organoleptic properties of a food. In this study on the gastrointestinal fate of nanoparticles, we have used cellulose nano-crystals (CNCs) as Pickering stabilising agents in oil in water emulsions. These emulsions were found to be highly stable against coalescence. The CNC and control emulsions were then exposed to simulated upper gastrointestinal tract digestion and the results compared to those obtained from a conventional protein stabilised emulsion. Finally the digested emulsions were exposed to murine intestinal mucosa and lipid and bile absorption was monitored. Importantly, the results show that the CNCs were entrapped in the intestinal mucus layer and failed to reach the underlying epithelium. This entrapment may also have led to the reduced absorption of saturated lipids from the CNC stabilised emulsion versus the control emulsion. The results show the potential of CNCs as a safe and effective emulsifier.

Scope Allergies to lipid transfer proteins involve severe adverse reactions; thus, effective and sustainable therapies are desired. Previous attempts disrupting disulfide bonds failed to maintain immunogenicity; thus, the aim is to design novel hypoallergenic Pru p 3 variants and evaluate the applicability for treatment of peach allergy. Methods and results Pru p 3 proline variant (PV) designed using in silico mutagenesis, cysteine variant (CV), and wildtype Pru p 3 (WT) are purified from Escherichia coli. Variants display homogenous and stable protein conformations with an altered secondary structure in circular dichroism. PV shows enhanced longterm storage capacities compared to CV similar to the highly stable WT. Using sera of 33 peach allergic patients, IgEbinding activity is reduced by 97% (PV) and 71% (CV) compared to WT. Both molecules show strong hypoallergenicity in Pru p 3 ImmunoCAP crossinhibition and histamine release assays. Immunogenicity of PV is demonstrated with a phosphatebased adjuvant formulation in a mouse model. Conclusions An in silico approach is used to generate a PV without targeting disulfide bonds, T cell epitopes, or previously reported IgE epitopes of Pru p 3. PV is strongly hypoallergenic while structurally stable and immunogenic, thus representing a promising candidate for peach allergen immunotherapy. FAST Food Allergy Specific Immunotherapy (201871) (VLID)3845545

Background: Fish currently supplies only 40% of the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) required to allow all individuals globally to meet the minimum intake recommendation of 500 mg/d. Therefore, alternative sustainable sources are needed. Objective: The main objective was to investigate the ability of genetically engineered Camelina sativa (20% EPA) oil (CO) to enrich tissue EPA and DHA relative to an EPA-rich fish oil (FO) in mammals. Methods: Six-week-old male C57BL/6J mice were fed for 10 wk either a palm oil–containing control (C) diet or diets supplemented with EPA-CO or FO, with the C, low-EPA CO (COL), high-EPA CO (COH), low-EPA FO (FOL), and high-EPA FO (FOH) diets providing 0, 0.4, 3.4, 0.3, and 2.9 g EPA/kg diet, respectively. Liver, muscle, and brain were collected for fatty acid analysis, and blood glucose and serum lipids were quantified. The expression of selected hepatic genes involved in EPA and DHA biosynthesis and in modulating their cellular impact was determined. Results: The oils were well tolerated, with significantly greater weight gain in the COH and FOH groups relative to the C group (P < 0.001). Significantly lower (36–38%) blood glucose concentrations were evident in the FOH and COH mice relative to C mice (P < 0.01). Hepatic EPA concentrations were higher in all EPA groups relative to the C group (P < 0.001), with concentrations of 0.0, 0.4, 2.9, 0.2, and 3.6 g/100 g liver total lipids in the C, COL, COH, FOL, and FOH groups, respectively. Comparable dose-independent enrichments of liver DHA were observed in mice fed CO and FO diets (P < 0.001). Relative to the C group, lower fatty acid desaturase 1 (Fads1) expression (P < 0.005) was observed in the COH and FOH groups. Higher fatty acid desaturase 2 (Fads2), peroxisome proliferator–activated receptor α (Ppara), and peroxisome proliferator–activated receptor γ (Pparg) (P < 0.005) expressions were induced by CO. No impact of treatment on liver X receptor α (Lxra) or sterol regulatory element-binding protein 1c (Srebp1c) was evident. Conclusions: Oil from transgenic Camelina is a bioavailable source of EPA in mice. These data provide support for the future assessment of this oil in a human feeding trial.

Trabajo presentado a las III Jornadas Científicas CIAL Fórum, celebradas del 22 al 23 de noviembre de 2018 en el Instituto de Investigación en Ciencias de la Alimentación (CIAL)., Pectin is an anionic polysaccharide used in food applications which, due to its physical and chemical properties can modify the absorption of nutrients. The fact that there is a protection by polysaccharides to protein digestion can be very important when considering the absorption of nutrients and allergens in the small intestine such is the case of casein. One possible mechanism is through electrostatic binding to proteins, depending on the pH. Thus, the adsorption of pectin to casein can take place at pH 3.5-5.0 by the electrostatic attraction between the carboxylate group of pectin and cationic residue of casein. Hardly any investigation has been done on the interaction casein/pectin during digestion of the protein. In this work, we studied the effect of citrus pectin on the gastric digestion of sodium caseinate in a semi-dynamic gastric model. Different mixtures of caseinate and pectin (1/0.08-1/3.4) were assayed and the changes in the protein fraction due to the gastric digestion were followed by SDS-PAGE. After digestion, diffuse bands corresponding to the formation of peptides, whose intensity was greater when the ratio caseinate/pectin was lower, were observed. In addition, a slight displacement to areas of lower molecular mass was also detected. This was probably due to a protective effect of pectin, mainly after 1 h of gastric digestion. The best ratio caseinate/pectin was 1/0.08, since the other values (1/0.85 and 1/3.4) gave rise to lower initial pH values (4.83 and 4.38, respectively) near to the optimum pH of pepsin (1.5-4.5) that could have favored the digestion. With the aim to investigate if other parameters such as the molecular mass could affect, citrus pectin treated with pectinolytic enzymes such as Viscozyme® and Glucanex®200 G were used. SDS-PAGE analyses indicated that, besides pH that affect the electrostatic bindings between the polysaccharide and protein, the degree of polymerization of pectin plays also an important role in the casein digestion by steric hindrance. Although more investigation should be carried out to go more insight in the involved mechanism, the obtained results underline the protection of pectin on the digestion of sodium caseinate, particularly evident at times lower than two hours., This work has been funded by MINECO of Spain: Project AGL2014-53445-R. MV thanks Salvador de Madariaga Program for the economic support of this project.