Interfacial adsorption and activity of pancreatic lipase-related protein 2 onto heterogeneous plant lipid model membranes.

Pancreatic lipase related-protein 2 (PLRP2) exhibits remarkable galactolipase and phospholipase A1 activities, which depend greatly on the supramolecular organization of the substrates and the presence of surfactant molecules such as bile salts. The objective of the study was to understand the modulation of the adsorption mechanisms and enzymatic activity of Guinea pig PLRP2 (gPLRP2), by the physical environment of the enzyme and the physical state of its substrate. Langmuir monolayers were used to reproduce homogeneous and heterogeneous photosynthetic model membranes containing galactolipids (GL), and/or phospholipids (PL), and/or phytosterols (pS), presenting uncharged or charged interfaces.

Interfacial organization and phase behavior of mixed galactolipid-DPPC-phytosterol assemblies at the air-water interface and in hydrated mesophases.

The structural behavior of model assemblies composed of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), the two main galactolipids found in plants, was investigated at the air/water interface and in aqueous dispersion. To approach the composition of the natural photosynthetic membranes, tunable Langmuir model membrane of galactolipids (GL) were used, and were complexified to form either heterogenous binary or ternary assemblies of GL, phospholipids (PL), and phytosterols (pS). The impact of pS, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or both on the structural properties of GL membrane was studied.

Digestibility and oxidative stability of plant lipid assemblies: An underexplored source of potentially bioactive surfactants?

Most lipids in our diet come under the form of triacylglycerols that are often redispersed and stabilized by surfactants in processed foods. In plant however, lipid assemblies constitute interesting sources of natural bioactive and functional ingredients. In most photosynthetic sources, polar lipids rich in ω3 fatty acids are concentrated.

Stability to oxidation and interfacial behavior at the air/water interface of minimally-processed versus processed walnut oil-bodies.

Oil bodies (OB), the form of triacylglycerol storage in seeds, are interesting natural assemblies for nutritional applications. In walnuts, OB contain an important amount of polyunsaturated fatty acids that could be interesting food ingredients but may be prone to oxidation. The oxidative and interfacial behavior of walnut OB, either minimally-processed or after processing, were compared with processed complex walnut juice.

In Vivo Digestion of Egg Products Enriched with DHA: Effect of the Food Matrix on DHA Bioavailability.

The aim of the present study was to determine to what extent the food matrix could affect the release of docosahexaenoic acid (DHA) during digestion and its incorporation into systemic circulation. In this aim, three DHA-enriched egg products having the same composition but different structure were developed: omelet, hard-boiled egg, and mousse. Then, nine pigs fitted with T-shape cannulas at duodenal level and a jugular venous catheter were fed with the DHA-enriched egg products, and duodenal effluents and plasma were collected throughout the postprandial period.

Dietary lipids and cardiometabolic health: a new vision of structure-activity relationship.

Purpose Of Review: The impact of dietary lipids on cardiometabolic health was mainly studied considering their fatty acid composition. This review aims to present the recent change in paradigm whereby the food matrix, the molecular and supramolecular structures of dietary lipids modulate their digestive fate and cardiometabolic impact.

Recent Findings: Epidemiological studies have reported that the metabolic impact of full-fat dairy products is better than predictable upon saturated fatty acid richness.

Enzymes to unravel bioproducts architecture.

Enzymes are essential and ubiquitous biocatalysts involved in various metabolic pathways and used in many industrial processes. Here, we reframe enzymes not just as biocatalysts transforming bioproducts but also as sensitive probes for exploring the structure and composition of complex bioproducts, like meat tissue, dairy products and plant materials, in both food and non-food bioprocesses. This review details the global strategy and presents the most recent investigations to prepare and use enzymes as relevant probes, with a focus on glycoside-hydrolases involved in plant deconstruction and proteases and lipases involved in food digestion.

Physico-chemical behaviors of human and bovine milk membrane extracts and their influence on gastric lipase adsorption.

Milk fat globule membrane conditions the reactivity and enzymatic susceptibility of milk lipids. The use of bovine membrane extracts to make infant formulas more biomimetic of human milk has been suggested recently. A comparison of the physico-chemical behavior of human and bovine milk membrane extracts and their interaction with gastric lipase is here undertaken using biophysical tools.

Variations in gastrointestinal lipases, pH and bile acid levels with food intake, age and diseases: Possible impact on oral lipid-based drug delivery systems.

The lipids and some surfactants present in oral lipid-based drug delivery systems are potential substrates for the various lipases involved in gastrointestinal (GI) lipolysis. The levels of these enzymes, together with pH and biliairy secretion, are important parameters that condition the fate of lipid-based formulations (LBF) and the dispersion, solubilization and absorption of lipophilic drugs in the GI tract. Since in vitro methods of digestion are now combined with dissolution assays for a better assessment of LBF performance, it is essential to have a basic knowledge on lipase, pH and bile acid (BA) levels in vivo to develop relevant in vitro models.

Impact of human milk pasteurization on the kinetics of peptide release during in vitro dynamic digestion at the preterm newborn stage.

Holder pasteurization (62.5 °C, 30 min) of human milk denatures beneficial proteins. The present paper aimed to assess whether this can affect the kinetics of peptide release during digestion at the preterm stage.

Impact of homogenization of pasteurized human milk on gastric digestion in the preterm infant: A randomized controlled trial.

Background & Aims: It has been suggested that homogenization of Holder-pasteurized human milk (PHM) could improve fat absorption and weight gain in preterm infants, but the impact on the PHM digestive kinetics has never been studied. Our objective was to determine the impact of PHM homogenization on gastric digestion in preterm infants.

Methods: In a randomized controlled trial, eight hospitalized tube-fed preterm infants were their own control to compare the gastric digestion of PHM and of homogenized PHM (PHHM).

Eleostearic phospholipids as probes to evaluate antioxidants efficiency against liposomes oxidation.

Regardless of the applications: therapeutic vehicle or membrane model to mimic complex biological systems; it is of a great importance to develop simplified, reproducible and rapid model assays allowing for a relevant assessment of the liposomal membrane oxidation and therefore antioxidant activity of selected molecules. Here, we describe a new and high-throughput assay that we called "Vesicle Conjugated Autoxidizable Triene (VesiCAT)". It is based on specific UV absorbance spectral properties of a new phospholipid probe, synthesized with natural conjugated eleostearic acid extracted from Tung oil.

Polar lipid composition of bioactive dairy co-products buttermilk and butterserum: Emphasis on sphingolipid and ceramide isoforms.

Bioactive lipids of the milk fat globule membrane become concentrated in two co-products of the butter industry, buttermilk and butterserum. Their lipid composition is detailed here with special emphasis on sphingolipid composition of nutritional interest, determined using GC, HPLC and tandem mass spectrometry. Butterserum was 2.

Impact of human milk pasteurization on gastric digestion in preterm infants: a randomized controlled trial.

Background: Holder pasteurization has been reported to modify human milk composition and structure by inactivating bile salt-stimulated lipase (BSSL) and partially denaturing some of its proteins, potentially affecting its subsequent digestion.

Objective: We sought to determine the impact of human milk pasteurization on gastric digestion (particularly for proteins and lipids) in preterm infants who were fed their mothers' own milk either raw or pasteurized.

Design: In a randomized controlled trial, 12 hospitalized tube-fed preterm infants were their own control group in comparing the gastric digestion of raw human milk (RHM) with pasteurized human milk (PHM).

A mixture of milk and vegetable lipids in infant formula changes gut digestion, mucosal immunity and microbiota composition in neonatal piglets.

Purpose: Although composition of infant formula has been significantly improved during the last decade, major differences with the composition and structure of breast milk still remain and might affect nutrient digestion and gut biology. We hypothesized that the incorporation of dairy fat in infant formulas could modify their physiological impacts by making their composition closer to that of human milk. The effect of milk fat and milk fat globule membrane (MFGM) fragments in infant formulas on gut digestion, mucosal immunity and microbiota composition was evaluated.

Impact of pasteurization of human milk on preterm newborn in vitro digestion: Gastrointestinal disintegration, lipolysis and proteolysis.

Human milk feeding is an important recommendation for preterm newborns considering their vulnerability and digestive immaturity. Holder pasteurization (62.5°C, 30min) applied in milk banks modifies its biological quality and its microstructure.

Adsorption of gastric lipase onto multicomponent model lipid monolayers with phase separation.

The enzymatic lipolysis of complex natural lipoproteic assemblies such as milk fat globules is central in neonatal digestion. This process first requires the rapid adsorption of a lipolytic enzyme, gastric lipase, onto the membrane enveloping the triglyceride substrate before the onset of catalytic activity. The interactions governing lipase adsorption onto this complex lipid/water interface are not fully elucidated.

Impact of human milk pasteurization on the kinetics of peptide release during in vitro dynamic term newborn digestion.

Holder pasteurization (62.5°C, 30 min) ensures sanitary quality of donor's human milk but also denatures beneficial proteins. Understanding whether this further impacts the kinetics of peptide release during gastrointestinal digestion of human milk was the aim of the present paper.

Milk Polar Lipids Affect In Vitro Digestive Lipolysis and Postprandial Lipid Metabolism in Mice.

Background: Polar lipid (PL) emulsifiers such as milk PLs (MPLs) may affect digestion and subsequent lipid metabolism, but focused studies on postprandial lipemia are lacking.

Objective: We evaluated the impact of MPLs on postprandial lipemia in mice and on lipid digestion in vitro.

Methods: Female Swiss mice were gavaged with 150 μL of an oil-in-water emulsion stabilized with 5.

The structure of infant formulas impacts their lipolysis, proteolysis and disintegration during in vitro gastric digestion.

Milk lipids supply most of the calories necessary for newborn growth in maternal milk or infant formulas. The chemical composition of infant formulas has been optimized but not the structure of the emulsion. There is still a major difference between the native emulsions of milk fat globules and processed submicronic emulsions in infant formulas.

Structure-function relationship of the milk fat globule.

Purpose Of Review: The complex biochemical composition and physical structure of the milk fat globule (MFG) are presented as a basis for its paradoxical metabolic fate: MFG is a rapid conveyor of energy through its triacylglycerol (TAG) core but contains some low-digestible bioactive complex lipids and proteins, which influence lipid metabolism and contribute to intestinal and systemic health.

Recent Findings: MFG structure modulates gastrointestinal lipolysis, postprandial lipemia and even the postprandial fate of ingested fatty acids. Proof-of-concept of the nutritional programming induced by early consumption of an emulsion biomimetic of MFG compared with a typical infant formula was published in an animal model (mice).

Specificity of infant digestive conditions: some clues for developing relevant in vitro models.

Digestion of nutrients is an essential function of the newborn infant gut to allow growth and development and understanding infant digestive function is essential to optimize nutrition and oral drug delivery. Ethical considerations prohibit invasive in vivo trials and as a consequence in vitro assays are often conducted. However, the choice of in vitro model parameters are not supported by an exhaustive analysis of the literature and do not mimic precisely the digestive conditions of the infant.

Time course and specificity of lipolysis in Swiss cheese.

Controlling lipolysis in cheese is necessary to ensure the formation of desirable flavor. To get a better understanding of the mechanism of lipolysis in Swiss cheese, cheeses were manufactured with and without (control) the addition of Propionibacterium freudenreichii. Products of lipolysis were quantified throughout ripening.